426 results on '"Cutaneous receptor"'
Search Results
2. Tactile sensitivity in the rat: a correlation between receptor structure and function
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Lucia Guzun, Pascal Fortier-Poisson, Allan M. Smith, and Jean-Sébastien Langlais
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Biology ,Cutaneous receptor ,Forelimb ,medicine ,Animals ,Receptor ,Skin ,Cutaneous receptors ,integumentary system ,Rapidly adapting ,General Neuroscience ,Slowly adapting ,Anatomy ,Hand ,Median nerve ,Median Nerve ,Rats ,Structure and function ,Merkel complexes ,Meissner corpuscles ,Dermal papillae ,medicine.anatomical_structure ,Merkel cell ,Mechanoreceptors ,Research Article ,Pacinian Corpuscle - Abstract
Single cutaneous fibers were recorded in the median nerve of the deeply anesthetized rat and the receptor morphology in the forelimb glabrous skin was analyzed to establish a probable correlation between receptor anatomy and physiology. Receptor complexes in the glabrous skin of the rat forelimb were stained immunologically with antibodies NF-200 and PGP-9.5, confirming the presence of Meissner corpuscles and Merkel complexes within the dermal papilla similar to other mammals including primates. Both the Meissner corpuscles and Merkel cell complexes were sparse and located in the pyramidal-shaped palmer pads and the apex of the digit extremities. They were almost totally absent elsewhere in the glabrous skin. No Ruffini receptors or Pacinian corpuscles were found in our samples. A total of 92 cutaneous fibers were retained long enough for analysis. Thirty-five (38%) were characterized as rapidly adapting fibers (RA) and 57 (62%) were slowly adapting afferents (SA). Despite the very limited number of receptors at the tip of the digit, RA receptors outnumbered SA fibers 3.2/1.0. In contrast, SA fibers on the thenar pad outnumbered RA receptors by a ratio of 3–1. Despite the very limited number of low threshold mechanoreceptors in the glabrous skin of the rat forelimb, the prevalence of SA afferents in the palm and more frequent occurrence of RA afferents in the digit extremity suggest differences in functionality both for locomotion and object manipulation.
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- 2021
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3. An artificial neural tactile sensing system
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Wanjun Park, Kum Seok Nam, Jong-Seok Kim, Jaehun Kim, Byong-Deok Choi, Dong Hee Son, Sungwoo Chun, Seongjun Park, Dong Pyo Jang, Sung-Phil Kim, Inchan Youn, Yong Jeong, Young-Jin Kim, Hachul Jung, Changhyun Pang, Sung Jun Jung, Youngin Choi, Gwangyeob Lee, Kang Il Song, and Yongsang Yoo
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business.industry ,Computer science ,Deep learning ,Motor nerve ,Robotics ,Sensory system ,Tactile perception ,Signal ,Electronic, Optical and Magnetic Materials ,Transmission (telecommunications) ,Cutaneous receptor ,Computer vision ,Artificial intelligence ,Electrical and Electronic Engineering ,business ,Instrumentation - Abstract
Humans detect tactile stimuli through a combination of pressure and vibration signals using different types of cutaneous receptor. The development of artificial tactile perception systems is of interest in the development of robotics and prosthetics, and artificial receptors, nerves and skin have been created. However, constructing systems with human-like capabilities remains challenging. Here, we report an artificial neural tactile skin system that mimics the human tactile recognition process using particle-based polymer composite sensors and a signal-converting system. The sensors respond to pressure and vibration selectively, similarly to slow adaptive and fast adaptive mechanoreceptors in human skin, and can generate sensory neuron-like output signal patterns. We show in an ex vivo test that undistorted transmission of the output signals through an afferent tactile mouse nerve fibre is possible, and in an in vivo test that the signals can stimulate a rat motor nerve to induce the contraction of a hindlimb muscle. We use our tactile sensing system to develop an artificial finger that can learn to classify fine and complex textures by integrating the sensor signals with a deep learning technique. The approach can also be used to predict unknown textures on the basis of the trained model. A tactile sensing system that can learn to identify different types of surface can be created using sensors that mimic the fast and slow responses of mechanoreceptors found in human skin.
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- 2021
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4. Withdrawal reflex: philosophy and physiology
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Tiengo, M., Gullo, Antonino, editor, Tiengo, M., editor, Paladini, V. A., editor, and Rawal, N., editor
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- 1999
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5. Comparative and Functional Aspects of the Histological Organization of Cutaneous Receptors in Vertebrates
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Andres, K. H., v Düring, M., Zenker, Wolfgang, editor, and Neuhuber, Winfried L., editor
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- 1990
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6. From finger friction to brain activation: Tactile perception of the roughness of gratings
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Hua Zhu, Shengjie Bai, Yibing Shi, Chunai Hu, Rui Liu, and Wei Tang
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0301 basic medicine ,Materials science ,Friction ,genetic structures ,EEG, electroencephalograph ,ERP, event-related potential ,Tactile perception ,Surface finish ,Grating ,Stimulus (physiology) ,DOF, degree of freedom ,03 medical and health sciences ,0302 clinical medicine ,Cutaneous receptor ,P300 ,lcsh:Science (General) ,Gratings ,ComputingMethodologies_COMPUTERGRAPHICS ,Stress concentration ,lcsh:R5-920 ,Multidisciplinary ,Sensory stimulation therapy ,integumentary system ,SS-EP, steady-state evoked potentials ,Finite element analysis ,Brain activation ,030104 developmental biology ,030220 oncology & carcinogenesis ,Original Article ,lcsh:Medicine (General) ,Contact area ,psychological phenomena and processes ,lcsh:Q1-390 ,Biomedical engineering - Abstract
Graphical abstract, Highlights • Tactile perception is investigated from finger friction to brain activation. • Stress concentrations around mechanoreceptors are affected by the grating textures. • Friction coefficient of finger increases with increasing grating width and spacing. • P300 peak latency is related to the difference between target and non-target stimulus. • P300 evoked by gratings is related with tribological and mechanical properties of skin., The formation of tactile perception is related to skin receptors and the cerebral cortex. In order to systematically study the tactile perception from finger friction to the brain response, a 32-channel Brain Products system and two tri-axial force sensors were used to obtain electroencephalograph (EEG) and friction signals during fingers exploring grating surfaces. A finite element finger model was established to analyze the stress changes of the skin receptors during tactile perception. Samples with different grating widths and spaces were chosen. The results indicated that different gratings induced different stress concentrations within skin that stimulated Meissner and Merkel receptors. Skin friction was affected by gratings during the tactile perception. It was also found that P300 evoked by gratings was related with the skin deformation, contact area, friction force, and stress around cutaneous mechanoreceptors. The wider grating width generated larger skin deformation, friction force, and stress, which induced stronger tactile stimulation. The smaller grating spacing generated higher vibration frequency, inducing stronger tactile stimulation. The latency of the P300 peak was related to the difference between the textured target stimulus and the smooth non-target stimulus. This study proofed that there was a relationship between the activation in brain regions, surface friction, and contact conditions of skin during the tactile perception. It contributes to understanding the formation process and cognitive mechanism of tactile perception of different surface textures.
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- 2020
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7. Cutaneous and muscular afferents from the foot and sensory fusion processing: Physiology and pathology in neuropathies
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Guido Felicetti, Marco Schieppati, Manh-Cuong Do, and Philippe Thoumie
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medicine.medical_specialty ,Sensory Receptor Cells ,Stimulation ,Sensory system ,03 medical and health sciences ,0302 clinical medicine ,Physical medicine and rehabilitation ,Cutaneous receptor ,Skin Physiological Phenomena ,medicine ,Humans ,Muscle, Skeletal ,Gait ,Balance (ability) ,Vestibular system ,Proprioception ,business.industry ,Foot ,General Neuroscience ,Peripheral Nervous System Diseases ,medicine.disease ,Peripheral neuropathy ,Touch Perception ,030220 oncology & carcinogenesis ,Neurology (clinical) ,business ,030217 neurology & neurosurgery - Abstract
The foot-sole cutaneous receptors (section 2), their function in stance control (sway minimisation, exploratory role) (2.1), and the modulation of their effects by gait pattern and intended behaviour (2.2) are reviewed. Experimental manipulations (anaesthesia, temperature) (2.3 and 2.4) have shown that information from foot sole has widespread influence on balance. Foot-sole stimulation (2.5) appears to be a promising approach for rehabilitation. Proprioceptive information (3) has a pre-eminent role in balance and gait. Reflex responses to balance perturbations are produced by both leg and foot muscle stretch (3.1) and show complex interactions with skin input at both spinal and supra-spinal levels (3.2), where sensory feedback is modulated by posture, locomotion and vision. Other muscles, notably of neck and trunk, contribute to kinaesthesia and sense of orientation in space (3.3). The effects of age-related decline of afferent input are variable under different foot-contact and visual conditions (3.4). Muscle force diminishes with age and sarcopenia, affecting intrinsic foot muscles relaying relevant feedback (3.5). In neuropathy (4), reduction in cutaneous sensation accompanies the diminished density of viable receptors (4.1). Loss of foot-sole input goes along with large-fibre dysfunction in intrinsic foot muscles. Diabetic patients have an elevated risk of falling, and vision and vestibular compensation strategies may be inadequate (4.2). From Charcot-Marie-Tooth 1A disease (4.3) we have become aware of the role of spindle group II fibres and of the anatomical feet conditions in balance control. Lastly (5) we touch on the effects of nerve stimulation onto cortical and spinal excitability, which may participate in plasticity processes, and on exercise interventions to reduce the impact of neuropathy.
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- 2020
8. Merkel cells immunohistochemical study in striped dolphin (Stenella coeruleoalba) skin
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Caterina Faggio, Maria Cristina Guerrera, Marialuisa Aragona, Eugenia Rita Lauriano, Simona Pergolizzi, Nunziacarla Spanò, and Gioele Capillo
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0106 biological sciences ,0301 basic medicine ,Pathology ,medicine.medical_specialty ,Enkephalin ,Dolphins ,Neuropeptide ,Human echolocation ,Stenella coeruleoalba ,Biology ,010603 evolutionary biology ,01 natural sciences ,Antibodies ,03 medical and health sciences ,Cutaneous receptor ,biology.animal ,medicine ,Animals ,Humans ,Skin ,Dolphin ,Neurons ,integumentary system ,Neurotransmitters ,Cell Biology ,General Medicine ,Merkel cells ,030104 developmental biology ,medicine.anatomical_structure ,Dermal papillae ,Dolphin, Merkel cells, Mechanoreceptors, Neurotransmitters ,Immunohistochemistry ,Merkel cell ,Mechanoreceptors ,Developmental Biology - Abstract
Cetacean mechanical senses, such as hearing, echolocation, active touch and the perception of water movements, are essential for their survival. Dolphins skin possesses dense packing of dermal papillae associated with the cutaneous ridges that suggests a sensory function, furthermore they are well innervated and very sensitive to touch. This is mediated by mechanoreceptors, abundant in the region of the head and in the dorsal part of the body. Most odontocetes possess vibrissae (i.e., sensory hair) that have been well described in literature and present a microanatomy similar to that of terrestrial mammals. The aim of this study was to characterize Merkel cell through use of specific antibodies: Substance P, Anti-calbindin DK28, Anti-5HT, Leu- enkephalin, Protein Gene Product 9.5 (PGP9.5) and Anti-Human Neuronal Protein, for the first time. Merkel cells (MCs) in the dolphin skin are specialized skin receptors, characterized by their particular location and close association with nerve terminals. The presence of neuroendocrine markers and different neuropeptides confirms that MCs play also neuroendocrine function and are considered as part of the diffuse neuroendocrine system. Furthermore, the presence of Leu-enkephalin in Merkel cells could involve these cells in inflammatory responses in the skin.
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- 2019
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9. What is the effect and mechanism of kinesiology tape on muscle activity?
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Rasool Bagheri, Mohammad Reza Pourahmadi, Ali Reza Sarmadi, Ismail Ebrahimi Takamjani, Giti Torkaman, and Sayyed Hamed Fazeli
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Adult ,Male ,Complementary and Manual Therapy ,medicine.medical_specialty ,Physical Therapy, Sports Therapy and Rehabilitation ,H-Reflex ,Young Adult ,03 medical and health sciences ,0302 clinical medicine ,Cutaneous receptor ,medicine ,Humans ,Single-Blind Method ,Anesthetics, Local ,Muscle activity ,Muscle, Skeletal ,Physical Therapy Modalities ,Motor Neurons ,Kinesiology ,Foot ,Rehabilitation ,Significant difference ,030229 sport sciences ,Motor pool ,Athletic Tape ,Complementary and alternative medicine ,Anesthesia ,Physical therapy ,H-reflex ,Psychology ,030217 neurology & neurosurgery ,Lateral gastrocnemius - Abstract
Objective This study aimed to evaluate the effects of kinesiology tape, anesthesia, and kinesiology tape along with anesthesia, on motor neuron excitability. Participants Participants included 20 healthy men aged 20–35 years, who were examined over 5 sessions. Intervention The five experimental sessions included: control without applying the kinesiology tape or Eutectic Mixture of Local Anesthetics (EMLA); treatment only with EMLA; only kinesiology tape application; only sham tape application; and treatment with kinesiology tape and EMLA. Main outcome measures The H-reflex recruitment curve of the soleus and lateral gastrocnemius was recorded by a blinded assessor in the 5 separate sessions randomly assigned with 48 h washout periods. The major H-reflex parameters include: the H max /M max ratio, the H-reflex threshold stimulation intensity (H th ), the intensity of maximum H-reflex (Intensity Hmax ), the H-reflex ascending slope (H slp ), and the H-reflex ascending slope fixed into the first three points (first H slp ). Results The H-reflex parameters (H slope, first H slp , H th , and Intensity Hmax ) were facilitated by application of the kinesiology tape with and without EMLA; however, EMLA inhibited the H-reflex parameters (H max /M max ratio, H slp , first H slp , and H th ) in both the soleus and lateral gastrocnemius. The sham tape did not alter the H-reflex recruitment curve parameters. The statistical model revealed a significant difference between the kinesiology tape and the sham tape and control sessions, between kinesiology tape–EMLA and EMLA, and between kinesiology tape–EMLA and control session. Conclusions Results suggest that the kinesiology tape facilitates the muscle activity and the underlying mechanism on the gastrosoleus motor neuron pool involves the cutaneous receptors.
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- 2018
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10. Design of Electrocutaneous Tactile Display over Human Fingertip for Textural Applications in Space Manufacturing Feedback
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Ravikanth Dadi and P. Hariharan
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Computer science ,business.industry ,Distortion (optics) ,010102 general mathematics ,Perspective (graphical) ,Space manufacturing ,Stimulus (physiology) ,01 natural sciences ,03 medical and health sciences ,0302 clinical medicine ,Cutaneous receptor ,Human–computer interaction ,Home automation ,Human machine interaction ,Key (cryptography) ,General Earth and Planetary Sciences ,Noise (video) ,0101 mathematics ,business ,Actuator ,030217 neurology & neurosurgery ,General Environmental Science ,Haptic technology - Abstract
Haptics philosophy and haptics technology has taken a huge turn in defining the science of human touch. A verity of actuators and tactile displays has emerged to create a real time touch through augmented environment. Human machine interaction (HMI) or Human computer interaction (HCI) has become a key technology for feedback systems from industrial applications to home automation. In creating such technologies, it is quite often to get introduced with new advanced actuators or displays like vibro-tactile, electro-tactile, physical pins and combinational displays. In this paper, electro-tactile displays will be discussed due to its limited exposure over method of approach used in research. Electro-tactile or Electrocutaneous-tactile displays are monitored by applying electrical pulses over skin, by changing frequency and amplitude. In inception many studies have been conducted over flattened-electrodes which do not give maximum interaction possibilities over skin surface and sub-surface in detecting textural stimuli in one dimensional perspective. In this paper, the design of an electrode is studied using the human fingertip and ensures that the fingertip achieves maximum contact points to trigger the skin receptors. The design is formulated by examining six human subjects or participants (25 years to 30 years). The key application behind the design is smart manufacturing feedback systems and space manufacturing feedback systems, where surface area and noise distortion plays a key role. The paper discusses the need of Electrocutaneous tactile displays in various applications based on the utilization of the surface area around the fingertips. The study helps in achieving maximum surface points for contact using simple psychophysical or general physiology measurements.
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- 2018
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11. Morphological Fabrication of Rubber Cutaneous Receptors Embedded in a Stretchable Skin-Mimicking Human Tissue by the Utilization of Hybrid Fluid
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Ryo Ikeda, Kunio Shimada, Hideharu Takahashi, and Hiroshige Kikura
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soft robotics ,skin ,magnetic compound fluid ((MCF) ,Materials science ,hybrid fluid (HF) ,Bulbous corpuscle ,rubber ,Soft robotics ,electrolytic polymerization ,Human skin ,TP1-1185 ,Biochemistry ,Article ,Artificial skin ,magnetic compound fluid (MCF) ,Analytical Chemistry ,Natural rubber ,sensor ,Cutaneous receptor ,cutaneous receptors ,medicine ,Humans ,Electrical and Electronic Engineering ,Instrumentation ,Skin, Artificial ,Chemical technology ,technology, industry, and agriculture ,humanoid ,Atomic and Molecular Physics, and Optics ,body regions ,Mechanoreceptor ,medicine.anatomical_structure ,Touch ,mimesis ,visual_art ,visual_art.visual_art_medium ,Mechanoreceptors ,Free nerve ending ,Biomedical engineering - Abstract
Sensors are essential in the haptic technology of soft robotics, which includes the technology of humanoids. Haptic sensors can be simulated by the mimetic organ of perceptual cells in the human body. However, there has been little research on the morphological fabrication of cutaneous receptors embedded in a human skin tissue utilizing artificial materials. In the present study, we fabricated artificial, cell-like cutaneous receptors embedded in skin tissue mimicking human skin structure by utilizing rubber. We addressed the fabrication of five cutaneous receptors (free nerve endings, Krause and bulbs, Meissner corpuscles, Pacinian corpuscles and Ruffini endings). In addition, we investigated the effectiveness of the fabricated tissue for mechanical and thermal sensing. At first, in the production of integrated artificial skin tissue, we proposed a novel magnetic, responsive, intelligent, hybrid fluid (HF), which is suitable for developing the hybrid rubber skin. Secondly, we presented the fabrication by utilizing not only the HF rubber but our previously proposed rubber vulcanization and adhesion techniques with electrolytic polymerization. Thirdly, we conducted a mechanical and thermal sensing touch experiment with the finger. As a result, it demonstrated that intelligence as a mechanoreceptor or thermoreceptor depends on its fabric: the HF rubber sensor mimicked Krause and bulbs has the thermal and pressing sensibility, and the one mimicked Ruffini endings the shearing sensibility.
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- 2021
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12. Vibration thresholds in carpal tunnel syndrome assessed by multiple frequency vibrometry: a case-control study
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Lars B. Dahlin, Birgitta Rosén, Tommy Schyman, Anders Björkman, Gert Andersson, and Magnus Flondell
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medicine.medical_specialty ,Audiology ,Toxicology ,Vibrometry ,03 medical and health sciences ,Vibration perception ,lcsh:RC963-969 ,0302 clinical medicine ,Cutaneous receptor ,Electroneuronography ,medicine ,Carpal tunnel ,Carpal tunnel syndrome ,business.industry ,Vibrotactile sense ,Research ,Public Health, Environmental and Occupational Health ,Touch thresholds ,Vibration perception threshold ,Index finger ,Little finger ,medicine.disease ,030210 environmental & occupational health ,Peripheral ,nervous system diseases ,medicine.anatomical_structure ,lcsh:Industrial medicine. Industrial hygiene ,Sensibility ,business ,Safety Research ,030217 neurology & neurosurgery - Abstract
Background Carpal tunnel syndrome (CTS) is the most common compression neuropathy, but there is no gold standard for establishing the diagnosis. The ability to feel vibrations in the fingertips is dependent on the function in cutaneous receptors and afferent nerves. Our aim was to investigate vibration perception thresholds (VPTs) in patients with CTS using multi-frequency vibrometry. Methods Sixty-six patients (16 men and 50 women) with CTS, diagnosed from clinical signs and by electroneurography, and 66 matched healthy controls were investigated with multi-frequency vibrometry. The VPTs were assessed at seven frequencies (8, 16, 32, 64, 125, 250, and 500 Hz) in the index finger and little finger bilaterally. The severity of the CTS was graded according to Padua and the patient’s subjective symptoms were graded according to the Boston carpal tunnel questionnaire. Touch thresholds were assessed using the Semmes-Weinstein monofilaments. Results Patients with CTS had significantly higher VPTs at all frequencies in the index finger and in 6 out of 7 frequencies in the little finger compared to the controls. However, the VPT was not worse in patients with more severe CTS. Patients with unilateral CTS showed significantly higher VPTs in the affected hand. There were no correlations between VPTs and electrophysiological parameters, subjective symptoms, or touch threshold. Conclusions Patients with CTS had impaired VPTs at all frequencies compared to the controls. Since the VPTs are dependent on function in peripheral receptors and their afferent nerves, multi-frequency vibrometry could possibly lead to diagnosis of CTS.
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- 2017
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13. Effects of contact method and acclimation on temperature and humidity in touch perception
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Masayuki Takatera, Xuemei Ding, Yanyan Wang, Wen-Yan Feng, Quan-Hai Li, Fukui Pan, Sachiko Sukigara, Bo-an Ying, Xin-Xing Wu, Jun-Yan Hu, Yi Li, Yongjun Sun, Chunhong Zhu, Xin Zhang, and Xiao Liao
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010407 polymers ,medicine.medical_specialty ,Polymers and Plastics ,Cerebrum ,Audiology ,01 natural sciences ,0104 chemical sciences ,03 medical and health sciences ,0302 clinical medicine ,medicine.anatomical_structure ,Cutaneous receptor ,Touch Perception ,medicine ,Chemical Engineering (miscellaneous) ,Contact method ,Psychology ,030217 neurology & neurosurgery - Abstract
Physical stimuli from contacted objects are recorded by skin receptors and are transmitted to neural signals to the cerebrum to generate touch perceptions. Despite numerous studies having been conducted on the link between the physical properties of contacted objects and psychological sensations, factors besides the stimuli themselves have seldom been investigated. The contact method and acclimation to environmental factors, such as temperature and humidity, could affect the functions of responsible receptors, which, in consequence, might affect the touch perception. This study is designed around a series of experiments involving 226 human subjects adapted to the climate environments of six East-Asia cities. The results revealed that the contact method affected the responses of smoothness sensation but not the stimuli discriminations. This agrees with the hypothesis that both the slowly adapting type I (SA1) fiber and the Pacinian afferent (PC) fiber are responsible for smoothness sensation. SA1 fibers can function through passive touch because of a superficial location in the dermis, while PC fibers, which are located deeper in the dermis, are triggered during active touching. The effect of contact method on softness sensation is not significant because the responsible receptor is the SA1 fiber. The effects of acclimation to temperature and relative humidity were also investigated. Positive relationships were found with smoothness perception and negative relationships were found with warmth perception. This suggests that acclimation to temperature and relative humidity can affect the receptor thresholds and, in consequence, affect the touch sensation.
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- 2017
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14. Dermo-optical perception of the visible range different wavelengths electromagnetic radiation by the palms skin of visually
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O. V. Shpachenko, Vladimir Titar, V. M. Mizrahi, Iu. V. Ielchishcheva, and A. V. Melnikova
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Physics ,Baroreceptor ,genetic structures ,media_common.quotation_subject ,05 social sciences ,030229 sport sciences ,Stimulus (physiology) ,Somatosensory system ,050105 experimental psychology ,03 medical and health sciences ,0302 clinical medicine ,Cutaneous receptor ,Perception ,Thermoreceptor ,0501 psychology and cognitive sciences ,Receptor ,Neuroscience ,Visible spectrum ,media_common - Abstract
Background. There is no single point of view which would explain the exact mechanisms of dermo-optical perception and nonspecific stimuli brain processing features at the moment, but to understand this perception peculiarities it is important to study the different skin receptors response to different colors. Objectives. The work aim is to determine the visible range different wavelengths electromagnetic radiation influence on the palms skin different types somatosensory receptors activity and nerve fibers involved in the skin innervation. Materials and methods. The experiments involved 12 visually impaired children (at their request and with their parents permission). The various somatosensory receptors condition measurement located on the palms, as well as the skin innervation of visually impaired children who participated in the dermo-optical perception training, was performed using the device "KSD" by recording and computer analysis of the electromagnetic oscillations emitted by the organism. Results. An experimental study of changes in the various somatosensory receptors activity located on the palms, as well as the visually impaired children skin innervation under the visible range different wavelengths electromagnetic radiation action was performed. It was found that under the light action, depending on the specific wavelengths, the studied receptors and nerve fibers are activated or suppressed. An increase in the thermal sensitivity activity (Ruffini's body) under the electromagnetic radiation influence on the palms skin in the wave range from 380-700 nm (in the entire visible light spectral range). The greatest activation was observed in «warm» (red, orange) and green colors. On white, black and «cold» colors (blue, blue) the Ruffini's bodies activation was less than on «warm» colors. Conclusions. The obtained experimental results indicate the palms skin various somatosensory receptors ability to adapt to the some information perception with a non-specific stimulus - the visible range electromagnetic radiation. It was found that the palms skin dermo-optical perception is due not only to temperature sensitivity (provided by thermoreceptors), but also to other types of receptors: baroreceptors (Pacinian corpuscles), tactile receptors (Meissner's corpuscles), mechanoreceptors (Golgi receptors).
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- 2020
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15. Using Cutaneous Receptor Vibration to Uncover the Effect of Transcranial Magnetic Stimulation (TMS) on Motor Cortical Excitability
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Ana Jerković, Maja Rogić Vidaković, Mladen Russo, Ana Kostović, Igor Vujović, Marin Peko, Ante Knežić, Mario Mihalj, Maja Stella, Davor Ljubenkov, Zoran Đogaš, Maximilian Vincent Hagelien, Jure Baban, Benjamin Benzon, and Joško Šoda
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Adult ,Male ,medicine.medical_specialty ,Neurology ,medicine.medical_treatment ,Stimulation ,030204 cardiovascular system & hematology ,Vibration ,Fingers ,03 medical and health sciences ,0302 clinical medicine ,Cutaneous receptor ,Clinical Research ,Motor Evoked Potentials ,Pacinian Corpuscles ,Transcranial Magnetic Stimulation ,Afferent ,medicine ,Humans ,Muscle, Skeletal ,Neurorehabilitation ,business.industry ,Motor Cortex ,General Medicine ,Middle Aged ,Evoked Potentials, Motor ,Hand ,Electric Stimulation ,Healthy Volunteers ,Transcranial magnetic stimulation ,030220 oncology & carcinogenesis ,Time course ,Cortical Excitability ,Female ,Primary motor cortex ,business ,Neuroscience - Abstract
Background: Little is known about how vibrational stimuli applied to hand digits affect motor cortical excitability. The present transcranial magnetic stimulation (TMS) study investigated motor evoked potentials (MEPs) in the upper extremity muscle following high- frequency vibratory digit stimulation. Material/Methods: High-frequency vibration was applied to the upper extremity digit II utilizing a miniature electromagnetic solenoid- type stimulator-tactor in 11 healthy study participants. The conditioning stimulation (C) preceded the test magnetic stimulation (T) by inter-stimulus intervals (ISIs) of 5–500 ms in 2 experimental sessions. The TMS was applied over the primary motor cortex for the hand abductor pollicis-brevis (APB) muscle. Results: Dunnett’s multiple comparisons test indicated significant suppression of MEP amplitudes at ISIs of 200 ms (P=0.001), 300 ms (P=0.023), and 400 ms (P=0.029) compared to control. Conclusions: MEP amplitude suppression was observed in the APB muscle at ISIs of 200–400 ms, applying afferent signaling that originates in skin receptors following the vibratory stimuli. The study provides novel insight on the time course and MEP modulation following cutaneous receptor vibration of the hand digit. The results of the study may have implications in neurology in the neurorehabilitation of patients with increased amplitude of MEPs.
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- 2020
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16. Trigeminal somatosensory innervation of the head of a teleost fish with particular reference to nociception
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Sneddon, Lynne U.
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TRIGEMINAL nerve , *RAINBOW trout - Abstract
Trigeminal somatosensory receptors have not been characterised in teleost fish and studies in elasmobranchs have failed to identify nociceptors. The present study examined the trigeminal nerve of a teleost fish, the rainbow trout (Oncorhynchus mykiss) to determine what types of somatosensory receptors were present on the head of the trout specifically searching for nociceptors. Single unit recordings were made from receptive fields on the head of the fish innervated by the trigeminal nerve. Each receptive field was tested for sensitivity to mechanical, thermal and chemical stimulation. Five different receptor types were found: fast adapting receptors responding to mechanical stimulation; slowly adapting receptors responding to mechanical stimuli; polymodal nociceptors responding to mechanical, noxious thermal and chemical stimulation; mechanothermal nociceptors responding to mechanical stimulation and noxious heat; and mechanochemical receptors responsive to mechanical and chemical stimulation. Mechanical thresholds, receptive field diameter, conduction velocities and thermal thresholds of the receptors were determined and there was no significant difference between the receptor types in terms of these properties. Three shapes of action potential (AP) were recorded from these receptors: type 1 with no inflexion; type 2 with an inflexion on depolarisation; and type 3 with an inflexion on repolarisation. Conduction velocity, amplitude and duration of the APs, afterhypolarisation amplitude and duration, as well as the maximum rate of depolarisation were measured for each action potential type. No major differences were found when making comparisons within receptor type and between receptor types. The fish nociceptors had similar physiological properties to nociceptors found in higher vertebrates. [Copyright &y& Elsevier]
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- 2003
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17. The use of adaptive neuro-stimulation for rebalancing posture and muscular tone in a soccer team
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Matteo Crudeli, Giovanni Barassi, Rosa Grazia Bellomo, Raoul Saggini, Annamaria Porreca, Letizia Pezzi, Christianpasquale Visciano, Giuseppe Giannuzzo, and Niki Giannandrea
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Adult ,Male ,medicine.medical_specialty ,Adolescent ,Electric Stimulation Therapy ,Hamstring Muscles ,Physical Therapy, Sports Therapy and Rehabilitation ,Stimulation ,law.invention ,Young Adult ,03 medical and health sciences ,Tone (musical instrument) ,0302 clinical medicine ,Physical medicine and rehabilitation ,Randomized controlled trial ,law ,Cutaneous receptor ,Soccer ,Humans ,Medicine ,Single-Blind Method ,Orthopedics and Sports Medicine ,030212 general & internal medicine ,Young adult ,Postural Balance ,Electrical frequency ,business.industry ,Spinal reflex ,030229 sport sciences ,Sagittal plane ,medicine.anatomical_structure ,Muscle Tonus ,business - Abstract
BACKGROUND Posture and somatic structure could positively influence athletic gestures for their biomechanical implications. Working on neuromuscular activity, offers the possibility of intervention on postural control. The aim of this study was to demonstrate the possibility of interacting with the human body system through the spinal reflex pathway, starting from the stimulation of cutaneous receptors. METHODS Twenty soccer players were recruited: all were male aged 25.5±10.6 years. Patients were divided using a single-blind criterion into two groups, each containing ten subjects. The experimental group was treated with 2 pre-set programs 4 times a week with an adaptive neuro-stimulation (ANS) able to interact with cutaneous receptors through an ENF Physio® device with a range of electrical frequency of about 15-350 Hz; the placebo-controlled group received the treatment with the device switched off. Patients performed a myometric evaluation with the MyotonPRO® system and a postural one with the Rarog software at T0 before the treatment and at T1 after the four-week treatment. RESULTS After our intervention, we identified an improvement in muscular tone, in particular in the hamstring muscles (17.69%, right P
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- 2019
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18. Multimodal Sensing with a Three-Dimensional Piezoresistive Structure
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Yonggang Huang, Jeonghyun Kim, Yong Suk Oh, Seungyong Han, Zhaoqian Xie, Sang Min Won, Sung Bong Kim, Kun Hyuck Lee, Jong Yoon Lee, Kyeongha Kwon, Xueju Wang, Heling Wang, Woo Jin Jang, Hokyung Jang, Yechan Lee, Kaitlyn E. Crawford, Yihui Zhang, Bong Hoon Kim, Xuebo Yuan, John A. Rogers, Mengdi Han, and Haibo Li
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Computer science ,viruses ,Electronic skin ,General Physics and Astronomy ,Context (language use) ,02 engineering and technology ,Biosensing Techniques ,010402 general chemistry ,01 natural sciences ,Physical Phenomena ,Cutaneous receptor ,Artificial systems ,General Materials Science ,Computer vision ,Mechanical Phenomena ,Skin ,integumentary system ,business.industry ,General Engineering ,Temperature ,021001 nanoscience & nanotechnology ,Piezoresistive effect ,0104 chemical sciences ,Touch ,Artificial intelligence ,Electronics ,0210 nano-technology ,business ,Tactile sensor - Abstract
Sensors that reproduce the complex characteristics of cutaneous receptors in the skin have important potential in the context of artificial systems for controlled interactions with the physical environment. Multimodal responses with high sensitivity and wide dynamic range are essential for many such applications. This report introduces a simple, three-dimensional type of microelectromechanical sensor that incorporates monocrystalline silicon nanomembranes as piezoresistive elements in a configuration that enables separate, simultaneous measurements of multiple mechanical stimuli, such as normal force, shear force, and bending, along with temperature. The technology provides high sensitivity measurements with millisecond response times, as supported by quantitative simulations. The fabrication and assembly processes allow scalable production of interconnected arrays of such devices with capabilities in spatiotemporal mapping. Integration with wireless data recording and transmission electronics allows operation with standard consumer devices.
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- 2019
19. Losing touch: age-related changes in plantar skin sensitivity, lower limb cutaneous reflex strength, and postural stability in older adults
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Monica D. McKeown, Mark G. Carpenter, J. Timothy Inglis, and Ryan M. Peters
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Adult ,Male ,0301 basic medicine ,Aging ,medicine.medical_specialty ,Physiology ,Electromyography ,Vibration ,Young Adult ,03 medical and health sciences ,0302 clinical medicine ,Physical medicine and rehabilitation ,Tibialis anterior muscle ,Cutaneous receptor ,Physical Stimulation ,Skin Physiological Phenomena ,Sensory threshold ,Reflex ,medicine ,Postural Balance ,Humans ,Muscle, Skeletal ,Aged ,Balance (ability) ,Aged, 80 and over ,medicine.diagnostic_test ,business.industry ,General Neuroscience ,Posturography ,Middle Aged ,030104 developmental biology ,Lower Extremity ,Touch ,Sensory Thresholds ,Call for Papers ,Female ,business ,030217 neurology & neurosurgery - Abstract
Age-related changes in the density, morphology, and physiology of plantar cutaneous receptors negatively impact the quality and quantity of balance-relevant information arising from the foot soles. Plantar perceptual sensitivity declines with age and may predict postural instability; however, alteration in lower limb cutaneous reflex strength may also explain greater instability in older adults and has yet to be investigated. We replicated the age-related decline in sensitivity by assessing monofilament and vibrotactile (30 and 250 Hz) detection thresholds near the first metatarsal head bilaterally in healthy young and older adults. We additionally applied continuous 30- and 250-Hz vibration to drive mechanically evoked reflex responses in the tibialis anterior muscle, measured via surface electromyography. To investigate potential relationships between plantar sensitivity, cutaneous reflex strength, and postural stability, we performed posturography in subjects during quiet standing without vision. Anteroposterior and mediolateral postural stability decreased with age, and increases in postural sway amplitude and frequency were significantly correlated with increases in plantar detection thresholds. With 30-Hz vibration, cutaneous reflexes were observed in 95% of young adults but in only 53% of older adults, and reflex gain, coherence, and cumulant density at 30 Hz were lower in older adults. Reflexes were not observed with 250-Hz vibration, suggesting this high-frequency cutaneous input is filtered out by motoneurons innervating tibialis anterior. Our findings have important implications for assessing the risk of balance impairment in older adults.
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- 2016
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20. Anatomical Mapping and Density of Merkel Cells in Skin and Mucosae of the Dog
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O. Quesada, Antonio Fernández, Francisco Rodríguez, A. Espinosa-de-los-Monteros, Pedro Herráez, and Gustavo A. Ramírez
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0301 basic medicine ,Pathology ,medicine.medical_specialty ,Histology ,Population ,Biology ,behavioral disciplines and activities ,030207 dermatology & venereal diseases ,03 medical and health sciences ,0302 clinical medicine ,Cutaneous receptor ,medicine ,Oral mucosa ,Axon ,education ,Ecology, Evolution, Behavior and Systematics ,education.field_of_study ,integumentary system ,Keratin 20 ,Anatomy ,Hair follicle ,humanities ,030104 developmental biology ,medicine.anatomical_structure ,Epidermis ,Merkel cell ,Biotechnology - Abstract
Merkel cells (MCs) are specialized cutaneous receptor cells involved with tactile sense. Although the distribution of MCs has been extensively studied in humans and rodents, their precise distribution and density throughout skin in the dog has not previously been determined. Knowledge of their distribution could facilitate understanding of their functions. By using of immunohistochemistry, density, and anatomical mapping of the MCs population in the dog skin was determined. Assessment of the MCs innervation was also achieved. Different patterns were noted in epidermis, hair follicles, or mucosa, including variable-sized clusters, linear or horse-shaped arrangements, and scattered and individualized cells. MCs revealed great variations in density and distribution over the body surface, with the highest numbers in oral mucosa and facial skin. There was no correlation of MCs density with age, sex, type of breed, coat type or pigmentation. Between 41 and 65% of MCs in hairy and glabrous skin and 8-18% of MCs in oral mucosa were in intimate contact with intraepithelial axon terminals. These findings indicate that canine MCs are numerous in sensory receptive areas and may be associated with the tactile sense in the dog. The present article enhances the knowledge of the skin structure in this species. Anat Rec, 299:1157-1164, 2016. © 2016 Wiley Periodicals, Inc.
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- 2016
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21. Effect of cooling foot sole skin receptors on achilles tendon reflex
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Andresa M.C. Germano, Thomas L. Milani, and Günther Schlee
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0301 basic medicine ,Physiology ,Electromyography ,03 medical and health sciences ,Cellular and Molecular Neuroscience ,0302 clinical medicine ,Cutaneous receptor ,Physiology (medical) ,medicine ,Stretch reflex ,Achilles tendon ,medicine.diagnostic_test ,business.industry ,Anatomy ,Hypothermia ,musculoskeletal system ,Ankle jerk reflex ,body regions ,030104 developmental biology ,medicine.anatomical_structure ,Reflex ,Neurology (clinical) ,medicine.symptom ,business ,030217 neurology & neurosurgery ,Foot (unit) - Abstract
This study investigated whether a controlled reduction of foot sole temperature affects the Achilles tendon stretch reflex and plantar flexion. Methods Five stretch reflexes in 52 healthy subjects were evoked by Achilles tendon taps. Short latency responses of 3 muscles of the lower limb and maximal force of plantar flexion were analyzed. Foot sole hypothermia was induced by a thermal platform at various foot temperature conditions: Stage I (25°C), Stage II (12°C), Stage IIIa (0°C), and Stage IIIb (0°C). Results Reduction of plantar cutaneous inputs resulted in a decrease in amplitude of medial gastrocnemius and soleus as well as delays in time to maximal force of plantar flexion. Medial gastrocnemius, lateral gastrocnemius, and soleus were affected differently by induced cooling. No inhibition effects in reflexes were observed at 12°C. Conclusions The results suggest that input on the plantar foot sole participates complementarily in the Achilles stretch reflex Muscle Nerve, 2015. Muscle Nerve 53: 965-971, 2016.
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- 2016
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22. Sensory alteration patterns in burned patients
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Jorge Aguilera-Sáez, Jose Luis Seoane, Jordi Domènech, Ana Tirado-Esteban, and Juan P. Barret
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Adult ,Male ,Pain Threshold ,Burn injury ,Sensory system ,Critical Care and Intensive Care Medicine ,030207 dermatology & venereal diseases ,03 medical and health sciences ,0302 clinical medicine ,Cutaneous receptor ,Sensation ,medicine ,Humans ,Aged ,Retrospective Studies ,Aged, 80 and over ,business.industry ,Quantitative sensory testing ,030208 emergency & critical care medicine ,Retrospective cohort study ,General Medicine ,Hypoesthesia ,Middle Aged ,medicine.anatomical_structure ,Touch ,Peripheral nervous system ,Anesthesia ,Sensation Disorders ,Emergency Medicine ,Quality of Life ,Surgery ,Female ,medicine.symptom ,business ,Burns - Abstract
Introduction Burned patients may present with different type and severity of sensory dysfunction. Regenerative mechanisms in the peripheral nervous system are diminished after burn injury and thus unable to accurately regenerate somatosensitive skin receptors. The pattern by which neuronal regeneration occurs to regain this sensitivity in burn patients is still unclear. Patients and method This observational retrospective study focuses on determining the patterns of heat, heat-pain, cold, cold-pain, sympathetic skin response and touch following severe burns. Twenty-six burn patients with different type of burns were included in the study. The survey methods used included the Quantitative Sensory Test for termoalgesic measurement, electrical SSR and the Von Frey filaments for quantitative measurements of touch/pressure. Results The results showed that patients present with hypoesthesia to heat, cold, and touch in postburn skin areas compared with the contralateral healthy areas. However, in the heat-pain sensation, no hypoesthesia was noted. Conclusions Our results suggest that burn patients have a sensitivity dysfunction in postburned skin areas. The use of QST could be considered the technique to determine the sensitivity of burned patients. Although, more high-quality studies should to be done.
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- 2019
23. Thermosensory mapping of skin wetness sensitivity across the body of young males and females at rest and following maximal incremental running
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Antonino Bianco, Alessandro Valenza, Davide Filingeri, Valenza A., Bianco A., and Filingeri D.
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0301 basic medicine ,Adult ,Male ,Hot Temperature ,Physiology ,Rest ,Sensation ,Sensory system ,Biology ,Wetness ,Running ,03 medical and health sciences ,0302 clinical medicine ,Cutaneous receptor ,Physical Stimulation ,Skin Physiological Phenomena ,Humans ,Thermosensing ,Sensitivity (control systems) ,Skin wetness ,Exercise ,Skin ,Body surface area ,Sex Characteristics ,Foot ,Thermoreceptors ,Cold Temperature ,030104 developmental biology ,Touch Perception ,Touch ,Thermoreceptor ,Body region ,Female ,Sex ,Skin Temperature ,030217 neurology & neurosurgery ,Body Temperature Regulation - Abstract
Key points: Humans lack skin receptors for wetness (i.e. hygroreceptors), yet we present a remarkable wetness sensitivity. Afferent inputs from skin cold-sensitive thermoreceptors are key for sensing wetness; yet, it is unknown whether males and females differ in their wetness sensitivity across their body and whether high intensity exercise modulates this sensitivity. We mapped sensitivity to cold, neutral and warm wetness across five body regions and show that females are more sensitive to skin wetness than males, and that this difference is greater for cold than warm wetness sensitivity. We also show that a single bout of maximal exercise reduced the sensitivity to skin wetness (i.e. hygro-hypoesthesia) of both sexes as a result of concurrent decreases in thermal sensitivity. These novel findings clarify the physiological mechanisms underpinning this fundamental human sensory experience. In addition, they indicate sex differences in thermoregulatory responses and will inform the design of more effective sport and protective clothing, as well as thermoregulatory models. Abstract: Humans lack skin hygroreceptors and we rely on integrating cold and tactile inputs from A-type skin nerve fibres to sense wetness. Yet, it is unknown whether sex and exercise independently modulate skin wetness sensitivity across the body. We mapped local sensitivity to cold, neutral and warm wetness of the forehead, neck, underarm, lower back and dorsal foot in 10males (27.8±2.7years; 1.92±0.1m2 body surface area) and 10 females (25.4±3.9years; 1.68±0.1m2 body surface area), at rest and post maximal incremental running. Participants underwent our quantitative sensory test where they reported the magnitude of thermal and wetness perceptions (visual analogue scale) resulting from the application of a cold (5°C below skin temperature) wet (0.8mL of water), neutral wet and warm wet (5°C above skin temperature) thermal probe (1.32cm2) to five skin sites. We found that: (i) females were ∼14% to ∼17% more sensitive to cold-wetness than males, yet both sexes were as sensitive to neutral- and warm-wetness; (ii) regional differences were present for cold-wetness only, and these followed a craniocaudal increase that was more pronounced in males (i.e. the foot was ∼31% more sensitive than the forehead); and (iii) maximal exercise reduced cold-wetness sensitivity over specific regions in males (i.e. ∼40% decrease in foot sensitivity), and also induced a generalized reduction in warm-wetness sensitivity in both sexes (i.e. ∼4% to ∼6%). For the first time, we show that females are more sensitive to cold wetness than males and that maximal exercise induce hygro-hypoesthesia. These novel findings expand our knowledge on sex differences in thermoregulatory physiology.
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- 2019
24. Investigation on the cutaneous/proprioceptive contribution to the force sensation induced by electrical stimulation above tendon
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Akifumi Takahashi, Hiroyuki Kajimoto, and Kenta Tanabe
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Proprioception ,Computer science ,Golgi tendon organ ,05 social sciences ,Stimulation ,050105 experimental psychology ,Effective depth ,Tendon ,03 medical and health sciences ,0302 clinical medicine ,medicine.anatomical_structure ,Cutaneous receptor ,Deep tissue ,Sensation ,medicine ,0501 psychology and cognitive sciences ,Neuroscience ,030217 neurology & neurosurgery - Abstract
A method to present force sensation based on electrical stimulation to the tendon has been suggested, and the occurrence of the sensation was considered due to the contribution of proprioceptors such as Golgi tendon organs. However, there was no clear evidence about the contributing receptors and because the method uses percutaneous electrical stimulation, there are other candidates, the cutaneous receptors. In this paper, we conducted experiments to determine whether the force sensation generated by this method is due to cutaneous sensation or proprioception, by changing the effective depth of electrical stimulation with electrodes spacing. As a result, it was shown that when the electrical stimulation could reach to deep tissue receptors, the force sensation was felt clearer, suggesting possible contribution of the proprioceptor.
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- 2018
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25. Immediate effects of wearing knee length socks differing in compression level on postural regulation in community-dwelling, healthy, elderly men and women
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Timo Jaakkola, Jarmo Liukkonen, Mei Teng Woo, Jia Yi Chow, and Keith Davids
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Male ,medicine.medical_specialty ,computer.internet_protocol ,Frail Elderly ,tukisukat ,elderly population ,Biophysics ,tasapaino ,vanhukset ,compression socks ,Barefoot ,Somatosensory function ,03 medical and health sciences ,somatosensorinen järjestelmä ,0302 clinical medicine ,Physical medicine and rehabilitation ,postural regulation ,Cutaneous receptor ,Pressure ,Humans ,Medicine ,Elderly people ,Orthopedics and Sports Medicine ,ta315 ,Geriatric Assessment ,Postural Balance ,Aged ,Aged, 80 and over ,Singapore ,business.industry ,Healthy population ,Rehabilitation ,030229 sport sciences ,Healthy elderly ,Compression (physics) ,jalat ,SOCKS ,Lower Extremity ,Accidental Falls ,Female ,Independent Living ,business ,computer ,Stockings, Compression ,030217 neurology & neurosurgery ,ikääntyneet - Abstract
Background Stimulation of lower limbs’ cutaneous receptors and mechanoreceptors through compression garments could potentially increase somatosensory system efficiency and aid postural regulation in elderly individuals. Research question This study examined immediate effects of wearing knee length socks (KLS) of various compression levels on somatosensory function in community-dwelling healthy elderly men and women during a double-limb standing, balancing task. Methods A total of forty-six elderly participants (Male = 23), aged between 65 and 84 years old, randomly selected from the Singapore community-dwelling, healthy population. Three treatment interventions (wearing clinical compression socks; wearing non-clinical compression socks; wearing commercial socks) and one control condition (barefoot), in a counterbalanced order, were administered to participants while they performed a 30-s Romberg test, with four levels of performance difficulty: (1) standing on a stable surface with vision (SO); (2) a stable surface without vision (SC); (3) a foam surface with vision (FO); and (4), a foam surface without vision (FC). Results Results showed that immediate effects of applying KLS of various compression levels significantly reduced sway area, trace length, velocity, and anterior-posterior (AP) sway as compared to barefoot condition (control) during the FO task condition. Significance This finding indicates the positive immediate effects of garments on somatosensory system function and postural regulation in the elderly men and women, especially when standing on the unstable surface. Wearing compression KLS could be included as a viable intervention on top of other forms of balance training to reduce risk of falling in elderly people. peerReviewed
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- 2018
26. Adaptation to the absence of tactile and proprioceptive feedback in object handling
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Agnès Roby-Brami, Nathanaël Jarrassé, Fabrice R. Sarlegna, Ross Parry, Institut du Cerveau et de la Moëlle Epinière = Brain and Spine Institute (ICM), Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-CHU Pitié-Salpêtrière [AP-HP], Assistance publique - Hôpitaux de Paris (AP-HP) (AP-HP)-Sorbonne Université (SU)-Assistance publique - Hôpitaux de Paris (AP-HP) (AP-HP)-Sorbonne Université (SU), Assistance aux Gestes et Applications THErapeutiques (AGATHE), Institut des Systèmes Intelligents et de Robotique (ISIR), Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Institut National de la Santé et de la Recherche Médicale (INSERM), Institut des Sciences du Mouvement Etienne Jules Marey (ISM), Centre National de la Recherche Scientifique (CNRS)-Aix Marseille Université (AMU), Hôpital Raymond Poincaré [AP-HP], SARLEGNA, Fabrice, Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut National de la Santé et de la Recherche Médicale (INSERM)-CHU Pitié-Salpêtrière [AP-HP], Assistance publique - Hôpitaux de Paris (AP-HP) (AP-HP)-Sorbonne Université (SU)-Assistance publique - Hôpitaux de Paris (AP-HP) (AP-HP)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), Institut National de la Santé et de la Recherche Médicale (INSERM)-Institut des Systèmes Intelligents et de Robotique (ISIR), Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), and Aix Marseille Université (AMU)-Centre National de la Recherche Scientifique (CNRS)
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030506 rehabilitation ,Auditory feedback ,medicine.medical_specialty ,Object handling ,Proprioception ,genetic structures ,Computer science ,Rehabilitation ,GRASP ,Control subjects ,Somatosensory system ,03 medical and health sciences ,0302 clinical medicine ,Physical medicine and rehabilitation ,Cutaneous receptor ,medicine ,Sensory neuropathy ,Orthopedics and Sports Medicine ,[SDV.NEU]Life Sciences [q-bio]/Neurons and Cognition [q-bio.NC] ,[SDV.NEU] Life Sciences [q-bio]/Neurons and Cognition [q-bio.NC] ,0305 other medical science ,030217 neurology & neurosurgery - Abstract
Introduction/Background Dextrous manipulation necessitates efficient sensorimotor feedback mechanisms to orientate handheld objects, adjust for movement dynamics and respond to perturbations. In particular, cutaneous receptors and proprioception are paramount in the regulation of hand-object interactions (Johansson, 1991; Nowak et al., 2004). This study further examined the object handling skills of a person with massive peripheral deafferentation (consequent to sensory neuropathy) in order to improve knowledge of how people adapt/compensate for the loss of tactile/proprioceptive feedback. Material and method Object handling abilities of a deafferented woman (GL) were compared to eight age-matched control subjects using three experimental tasks: – discrete vertical movements; – functional grasp and place and; – static holding with perturbations (taps) applied to the top of the object—firstly by the person themselves and secondly by the experimenter. Tasks 1 and 3 were performed under full vision and blinded conditions. Grip force and object acceleration/orientation were recorded using a portable, instrumented object. Results When compared to control subjects, GL demonstrated a global increase in grip force with diminished temporal coupling to changes in object acceleration and limited ability to maintain orientation of the handheld object in the absence of visual feedback. All phases of the grasp and place task were of greater duration for GL and a qualitatively distinct acceleration profile was observed. In the hold perturbation tasks, GL exhibited greater time delays between perturbation and grip force response but proved efficient at gauging grip force response with respect to the magnitude of the perturbation. Conclusion Whilst proprioceptive deficits limit temporal precision of grip force adjustments in object handling, visuomotor strategies and auditory feedback may assist in regulating object orientation during functional tasks and grip force scaling during perturbations. Future studies might investigate the feasibility of augmented visual/auditory feedback devices to optimise object handling for people with somatosensory deficits.
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- 2018
27. How can the stimulation of plantar cutaneous receptors improve postural control? Review and clinical commentary
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Frédéric Viseux, Philippe Villeneuve, Antoine Lemaire, Pascal Charpentier, Sébastien Leteneur, and Franck Barbier
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medicine.medical_specialty ,Stimulation ,Context (language use) ,Sensory system ,050105 experimental psychology ,03 medical and health sciences ,0302 clinical medicine ,Physical medicine and rehabilitation ,Cutaneous receptor ,Feedback, Sensory ,Physiology (medical) ,medicine ,Humans ,0501 psychology and cognitive sciences ,Sensory cue ,Postural Balance ,Balance (ability) ,Afferent Pathways ,business.industry ,Foot ,05 social sciences ,Chronic pain ,General Medicine ,medicine.disease ,Neurology ,Standing Position ,Facilitation ,Neurology (clinical) ,business ,Mechanoreceptors ,030217 neurology & neurosurgery - Abstract
Postural control requires constant and subconscious postural sway to manage balance and achieve postural stability. These movements of regulation are based in particular on cutaneous plantar information. The foot constitutes a functional whole that participates in the mechanisms of postural control and regulation. It represents the direct interface between the body and the ground during quiet standing, and plantar cutaneous information contributes to postural control. Upright balance mechanically depends on the gravitational torque produced by the forces of gravity and reaction of the ground. In this context, the foot behaves like a sensory system for postural regulation whose objective is to maintain a state of stability within a changing and constraining environment. There is a relation between balance improvement and the facilitation of sensory feedback related to the activation of the plantar cutaneous mechanoreceptors. From a clinical point of view, the application of additional tactile cues may have therapeutic benefits in relation to fall prevention, or to improve specific types of chronic pain.
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- 2018
28. What do you feel if I apply transcranial electric stimulation? Safety, sensations and secondary induced effects
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Clarissa Ferrari, Anna Fertonani, and Carlo Miniussi
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Adult ,Male ,medicine.medical_specialty ,media_common.quotation_subject ,medicine.medical_treatment ,tES ,Questionnaire Sensations ,Transcranial direct current stimulation ,(tDCS) ,Transcranial random noise stimulation ,(tRNS), Transcranial alternating current stimulation ,(tACS) ,Sensation ,Stimulation ,Audiology ,Transcranial Direct Current Stimulation ,Somatosensory system ,Cutaneous receptor ,Evoked Potentials, Somatosensory ,Surveys and Questionnaires ,Physiology (medical) ,Perception ,medicine ,Humans ,Electrodes ,Aged ,Skin ,media_common ,Transcranial direct-current stimulation ,(tRNS) ,Age Factors ,Middle Aged ,Sensory Systems ,Intensity (physics) ,Transcranial alternating current stimulation ,medicine.anatomical_structure ,Neurology ,Scalp ,Female ,Neurology (clinical) ,Safety ,Psychology ,Neuroscience - Abstract
Objective: The goals of this work are to report data regarding a large number of stimulation sessions and to use model analyses to explain the similarities or differences in the sensations induced by different parameters of tES application. Methods: We analysed sensation data relative to 693 different tES sessions. In particular, we studied the effects on sensations induced by different types of current, categories of polarity and frequency, different timing, levels of current density and intensity, different electrode sizes and different electrode locations (areas). Results: The application of random or fixed alternating current stimulation (i.e., tRNS and tACS) over the scalp induced less sensation compared with transcranial direct current stimulation (tDCS), regardless of the application parameters. Moreover, anodal tDCS induced more annoyance in comparison to other tES. Additionally, larger electrodes induced stronger sensations compared with smaller electrodes, and higher intensities were more strongly perceived. Timing of stimulation, montage and current density did not influence sensations perception. The analyses demonstrated that the induced sensations could be clustered on the basis of the type of somatosensory system activated. Finally and most important no adverse events were reported. Conclusion: Induced sensations are modulated by electrode size and intensity and mainly pertain to the cutaneous receptor activity of the somatosensory system. Moreover, the procedure currently used to perform placebo stimulation may not be totally effective when compared with anodal tDCS. Significance: The reported observations enrich the literature regarding the safety aspects of tES, confirming that it is a painless and safe technique.
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- 2015
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29. A new method for characterizing hand dysfunction in cervical spondylotic myelopathy: a preliminary study
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Hayato Enoki, Y Nagano, Nobuaki Tadokoro, Toshikazu Tani, Kazunobu Kida, Masahiko Ikeuchi, and T Akutagawa
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Male ,030506 rehabilitation ,medicine.medical_specialty ,Pinch Strength ,Spinal Cord Diseases ,Disability Evaluation ,03 medical and health sciences ,0302 clinical medicine ,Physical medicine and rehabilitation ,Japan ,Feedback, Sensory ,Cutaneous receptor ,Fasciculus ,Spondylotic myelopathy ,Humans ,Medicine ,In patient ,Spasticity ,Aged ,Aged, 80 and over ,Hand Strength ,biology ,Proprioception ,business.industry ,Repetitive movements ,General Medicine ,Middle Aged ,Hand ,biology.organism_classification ,Magnetic Resonance Imaging ,Surgery ,body regions ,Neurology ,Cervical Vertebrae ,Female ,Spondylosis ,Neurology (clinical) ,medicine.symptom ,0305 other medical science ,business ,030217 neurology & neurosurgery - Abstract
A case–control investigation. The objective of this study was to quantitatively study impaired ability to appropriately adjust pinch strength while holding a small object in patients with cervical spondylotic myelopathy (CSM). Kochi Medical School Hospital, Japan. The subjects consisted of 19 CSM patients who had frequent episodes of failing to grasp and hold small objects in their daily life (Group A), 13 CSM patients who did not experience such episodes (Group B) and 16 healthy subjects (Control Group). We continuously measured the dynamic internal pressure of a pneumatic rubber object called a blower pinched by the subject, following two different sets of instructions: (1) pinching with eyes open and with the minimal strength required to prevent dropping; and (2) maintaining a constant pinch strength at given levels with eyes closed. Compared with the other two groups, Group A subjects used a significantly (P
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- 2015
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30. Control of cutaneous blood flow by central nervous system
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Youichirou Ootsuka and Mutsumi Tanaka
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sympathetic nervous system ,medicine.medical_specialty ,Sympathetic nervous system ,integumentary system ,Vasomotor ,Raphe ,Physiology ,business.industry ,Central nervous system ,cutaneous vasoconstriction ,Review ,Anatomy ,medullary raphé ,Preoptic area ,Midbrain ,medicine.anatomical_structure ,Endocrinology ,psychological hyperthermia ,Cutaneous receptor ,Physiology (medical) ,Internal medicine ,medicine ,Cutaneous innervation ,business ,preoptic area - Abstract
Hairless skin acts as a heat exchanger between body and environment, and thus greatly contributes to body temperature regulation by changing blood flow to the skin (cutaneous) vascular bed during physiological responses such as cold- or warm-defense and fever. Cutaneous blood flow is also affected by alerting state; we 'go pale with fright'. The rabbit ear pinna and the rat tail have hairless skin, and thus provide animal models for investigating central pathway regulating blood flow to cutaneous vascular beds. Cutaneous blood flow is controlled by the centrally regulated sympathetic nervous system. Sympathetic premotor neurons in the medullary raphé in the lower brain stem are labeled at early stage after injection of trans-synaptic viral tracer into skin wall of the rat tail. Inactivation of these neurons abolishes cutaneous vasomotor changes evoked as part of thermoregulatory, febrile or psychological responses, indicating that the medullary raphé is a common final pathway to cutaneous sympathetic outflow, receiving neural inputs from upstream nuclei such as the preoptic area, hypothalamic nuclei and the midbrain. Summarizing evidences from rats and rabbits studies in the last 2 decades, we will review our current understanding of the central pathways mediating cutaneous vasomotor control.
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- 2015
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31. Kinesthetic illusions attenuate experimental muscle pain, as do muscle and cutaneous stimulation
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André Gay, Jean-Marc Aimonetti, Jean-Pierre Roll, Edith Ribot-Ciscar, Institut des Sciences du Mouvement Etienne Jules Marey (ISM), Centre National de la Recherche Scientifique (CNRS)-Aix Marseille Université (AMU), Service de chirurgie plastique, Assistance Publique - Hôpitaux de Marseille (APHM), Laboratoire de Neurosciences intégratives et adaptatives (LNIA), and Aix Marseille Université (AMU)-Centre National de la Recherche Scientifique (CNRS)
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Adult ,Male ,Analgesic ,Sensory system ,Vibration ,Young Adult ,03 medical and health sciences ,0302 clinical medicine ,Cutaneous receptor ,Physical Stimulation ,medicine ,Humans ,Muscle, Skeletal ,Muscle Spindles ,Molecular Biology ,Pain Measurement ,030304 developmental biology ,0303 health sciences ,business.industry ,General Neuroscience ,Kinesthetic Illusions ,Myalgia ,Microneurography ,Illusions ,Hypertonic saline ,medicine.anatomical_structure ,Anesthesia ,[SDV.NEU]Life Sciences [q-bio]/Neurons and Cognition [q-bio.NC] ,Female ,Neurology (clinical) ,Ankle ,business ,Ankle Joint ,030217 neurology & neurosurgery ,Developmental Biology ,Cutaneous stimulation - Abstract
International audience; In the present study, muscle pain was induced experimentally in healthy subjects by administrating hypertonic saline injections into the tibialis anterior (TA) muscle. We first aimed at comparing the analgesic effects of mechanical vibration applied to either cutaneous or muscle receptors of the TA or to both types simultaneously. Secondly, pain alleviation was compared in subjects in whom muscle tendon vibration evoked kinesthetic illusions of the ankle joint. Muscle tendon vibration, which primarily activated muscle receptors, reduced pain intensity by 30% (p
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- 2015
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32. The role of muscle proprioceptors in human limb position sense: a hypothesis
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Uwe Proske
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Histology ,Sensory Receptor Cells ,Computer science ,Movement ,Sensory system ,Common method ,Cutaneous receptor ,Afferent ,Schema (psychology) ,Humans ,Computer vision ,Muscle, Skeletal ,Muscle Spindles ,Review Articles ,Molecular Biology ,Ecology, Evolution, Behavior and Systematics ,Proprioception ,business.industry ,Extremities ,Cell Biology ,Cortical map ,Space Perception ,Artificial intelligence ,Anatomy ,business ,Neuroscience ,Developmental Biology - Abstract
In this mini-review I have proposed that there are two kinds of position sense, one a sense of the position of one part of the body relative to another, the other a sense of the location in space of our body and its limbs. A common method used to measure position sense is to ask subjects to match with one arm the position adopted by the other. Here all of the evidence points to muscle spindles as the major proprioceptors, with cutaneous receptors acting as proprioceptors providing a supporting role. Other senses such as vision do not play a major role. The sense of localisation in space measured by pointing to the arm, rather than matching its position, I propose, is not served by proprioceptors but by exteroceptors, vision, touch and hearing. Here the afferent input is relayed to sensory areas of the brain, to address the postural schema, a cortical map of the body and limbs, specifying its size and shape. It is here that spatial location is computed. This novel interpretation of position sense as two separate entities has the advantage of proposing new, future experiments and if it is supported by the findings, it will represent an important step forward in our understanding of the central processing of spatial information.
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- 2015
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33. Skin receptors and intradermal nerves do not generate the sensory double peak
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Aravindakannan Therimadasamy, Einar Wilder-Smith, and Yee Cheun Chan
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Physiology ,Chemistry ,Stimulation ,Depolarization ,Sensory system ,Stimulus (physiology) ,Cellular and Molecular Neuroscience ,Negative phase ,Cutaneous receptor ,Physiology (medical) ,Anesthesia ,Biophysics ,Neurology (clinical) ,Anodal stimulation ,Receptor - Abstract
Introduction: The cause of the double peak observed at submaximal stimulation of sensory nerves is unknown. The first peak is generated under the cathode and the second under the anode. The double peak is thought to arise from intradermal nerves or skin receptors, and in this study we tested this assumption. Methods: We studied the effect of different stimulus durations on anodal peak latency in volunteers. Biphasic anodal stimulation was used to investigate the latent additive effect of the trailing negative phase on the partial depolarization induced by the initial positive phase. We further tested the maximal amplitude of anode-generated potentials to estimate the number of neural structures involved in their generation. Results: Increased stimulus duration caused anode-generated potential delay. Biphasic stimulation increased anode-generated amplitude 4-fold compared with monophasic stimulation. The anode-generated potential produced up to 85% of the supramaximal cathode-generated amplitude. Conclusions: The results suggest that the double peak arises from anodal break excitation and not from intradermal nerves or receptors. Muscle Nerve 52: 103–106, 2015
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- 2015
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34. [Skin receptors and therapeutic physical factors]
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Ulashchik Vs
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Sensory Receptor Cells ,business.industry ,General Medicine ,030207 dermatology & venereal diseases ,03 medical and health sciences ,0302 clinical medicine ,Cutaneous receptor ,030220 oncology & carcinogenesis ,Medicine ,Animals ,Humans ,business ,Receptor ,Neuroscience ,Physical Therapy Modalities ,Skin - Abstract
This review presents the data on the receptor function of the skin and its role in the formation of the body's response to the action of physical therapy. Especially much attention is given in the paper to the influence of ultrasound, microwaves, laser radiation, various medical environments, and other physical factors on the morphofunctional condition of the skin receptors. Possible mechanisms of changes in receptor activity under effects of physical therapeutic factors are analyzed. Moreover, the paper summarizes the directions of further possible studies on the interactions between physical factors and cutaneous receptors.В обзоре представлены сведения о рецепторной функции кожи и ее роли в формировании реакции организма на физиотерапевтические воздействия. Рассмотрено влияние ультразвука, микроволн, лазерного излучения, различных лечебных сред и других физических факторов на морфофункциональное состояние рецепторов кожи. Проанализированы возможные механизмы изменения активности рецепторов под действием физиотерапевтических факторов. Обсуждены направления дальнейших исследований взаимодействия физических факторов с кожными рецепторами.
- Published
- 2017
35. tactoRing
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Liwei Chan, Brendan Rooney, Seungwoo Je, and Andrea Bianchi
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InformationSystems_INFORMATIONINTERFACESANDPRESENTATION(e.g.,HCI) ,Computer science ,business.industry ,media_common.quotation_subject ,05 social sciences ,ComputingMethodologies_IMAGEPROCESSINGANDCOMPUTERVISION ,Wearable computer ,020207 software engineering ,02 engineering and technology ,Motion (physics) ,Tactile stimuli ,body regions ,Cutaneous receptor ,Perception ,0202 electrical engineering, electronic engineering, information engineering ,0501 psychology and cognitive sciences ,Computer vision ,Artificial intelligence ,Set (psychology) ,business ,Actuator ,050107 human factors ,Wearable technology ,media_common ,Haptic technology - Abstract
Smart rings are an emerging wearable technology particularly suitable for discrete notifications based on haptic cues. Previous work mostly focused on tactile actuators that stimulate only specific skin receptors on the finger, resulting in limited information expressiveness. We propose tactoRing, a novel tactile display that, by dragging a small tactor on the skin around the finger, excites multiple skin areas resulting in more accurate cue recognition. In this paper, we present the hardware and a perception study to understand the ability of users to recognize eight distinct points around the finger. Moreover, we show two different techniques to encode information through skin-dragging motion with accuracy up to 94%. We finally showcase a set of applications that, by combining sequences of tactile stimuli, achieve higher expressiveness than prior methods.
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- 2017
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36. Why wet feels wet? A neurophysiological model of human cutaneous wetness sensitivity
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Davide Filingeri, Simon Hodder, Damien Fournet, and George Havenith
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Male ,Communication ,Sense skin ,Physiology ,business.industry ,General Neuroscience ,Models, Neurological ,Neurophysiology ,Young Adult ,Touch Perception ,Touch ,Cutaneous receptor ,Skin Physiological Phenomena ,Humans ,Thermoreceptor ,Thermosensing ,Neurons, Afferent ,Sensitivity (control systems) ,Skin wetness ,business ,Psychology ,Neuroscience - Abstract
Although the ability to sense skin wetness and humidity is critical for behavioral and autonomic adaptations, humans are not provided with specific skin receptors for sensing wetness. It has been proposed that we “learn” to perceive the wetness experienced when the skin is in contact with a wet surface or when sweat is produced through a multisensory integration of thermal and tactile inputs generated by the interaction between skin and moisture. However, the individual roles of thermal and tactile cues and how these are integrated peripherally and centrally by our nervous system is still poorly understood. Here we tested the hypothesis that the central integration of coldness and mechanosensation, as subserved by peripheral A-nerve afferents, might be the primary neural process underpinning human wetness sensitivity. During a quantitative sensory test, we found that individuals perceived warm-wet and neutral-wet stimuli as significantly less wet than cold-wet stimuli, although these were characterized by the same moisture content. Also, when cutaneous cold and tactile sensitivity was diminished by a selective reduction in the activity of A-nerve afferents, wetness perception was significantly reduced. Based on a concept of perceptual learning and Bayesian perceptual inference, we developed the first neurophysiological model of cutaneous wetness sensitivity centered on the multisensory integration of cold-sensitive and mechanosensitive skin afferents. Our results provide evidence for the existence of a specific information processing model that underpins the neural representation of a typical wet stimulus. These findings contribute to explaining how humans sense warm, neutral, and cold skin wetness.
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- 2014
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37. Delta Opioid Receptors Presynaptically Regulate Cutaneous Mechanosensory Neuron Input to the Spinal Cord Dorsal Horn
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Bardoni, Rita, Tawfik, Vivianne, Wang, Dong, François, Amaury, Solorzano, Carlos, Shuster, Scott, Choudhury, Papiya, De Nooij, Joriene, Betelli, Chiara, Cassidy, Colleen, Smith, Kristen, de Nooij, Joriene C., Oise Mennicken, Franç, O'Donnell, Dajan, Kieffer, Brigitte, Basbaum, Allan, Macdermott, Amy, Gory Scherrer, Gré, Tawfik, Vivianne L., Solórzano, Carlos, O’Donnell, Dajan, Shuster, Scott A., Kieffer, Brigitte L., Woodbury, C. Jeffrey, Basbaum, Allan I., MacDermott, Amy B., Scherrer, Grégory, Franç, Amaury, Mennicken, Françoise, Sch Mol & Biomed Sci, University of Adelaide, Institut de Génomique Fonctionnelle (IGF), Université de Montpellier (UM)-Université Montpellier 1 (UM1)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Université Montpellier 2 - Sciences et Techniques (UM2)-Centre National de la Recherche Scientifique (CNRS), Departamento de Bioquímica, Instituto Nacional de Enfermedades Respiratorias, Institut de Génétique et de Biologie Moléculaire et Cellulaire (IGBMC), Université de Strasbourg (UNISTRA)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS), and AstraZeneca
- Subjects
[SDV.NEU.NB]Life Sciences [q-bio]/Neurons and Cognition [q-bio.NC]/Neurobiology ,Neurodegenerative ,Inbred C57BL ,Somatosensory system ,delta ,Mice ,0302 clinical medicine ,synapse ,Ganglia, Spinal ,Receptors, Opioid, delta ,Receptors ,2.1 Biological and endogenous factors ,Psychology ,pain ,Aetiology ,Neurons ,Analgesics ,0303 health sciences ,education.field_of_study ,General Neuroscience ,Pain Research ,Nociceptors ,Analgesics, Opioid ,medicine.anatomical_structure ,Spinal Cord ,Neurological ,Nociceptor ,Cognitive Sciences ,Chronic Pain ,Mechanoreceptors ,Spinal ,1.1 Normal biological development and functioning ,Neuroscience(all) ,Population ,Pain ,Opioid ,Biology ,δ-opioid receptor ,03 medical and health sciences ,Underpinning research ,Cutaneous receptor ,Spinal Cord Dorsal Horn ,medicine ,Animals ,education ,030304 developmental biology ,Neurology & Neurosurgery ,Mechanosensation ,Neurosciences ,pain, spinal cord, opioids, synapse ,spinal cord ,opioids ,Mice, Inbred C57BL ,nervous system ,Ganglia ,Calcium Channels ,Neuron ,Neuroscience ,030217 neurology & neurosurgery - Abstract
International audience; Cutaneous mechanosensory neurons detect mechanical stimuli that generate touch and pain sensation. Although opioids are generally associated only with the control of pain, here we report that the opioid system in fact broadly regulates cutaneous mecha-nosensation, including touch. This function is predominantly subserved by the delta opioid receptor (DOR), which is expressed by myelinated mecha-noreceptors that form Meissner corpuscles, Merkel cell-neurite complexes, and circumferential hair follicle endings. These afferents also include a small population of CGRP-expressing myelinated noci-ceptors that we now identify as the somatosensory neurons that coexpress mu and delta opioid receptors. We further demonstrate that DOR activation at the central terminals of myelinated mechanorecep-tors depresses synaptic input to the spinal dorsal horn, via the inhibition of voltage-gated calcium channels. Collectively our results uncover a molecular mechanism by which opioids modulate cuta-neous mechanosensation and provide a rationale for targeting DOR to alleviate injury-induced mechanical hypersensitivity.
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- 2014
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38. Large body sways help maintaining balance by increasing the transmission of cutaneous input following prolonged periods of reduced body oscillations: EEG, microneurography and behavioral evidence
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Jean Blouin, Rochelle Ackerley, Martin Simoneau, Laurence Mouchnino, Jean-Marc Aimonetti, Edith Ribot-Ciscar, Pascale Chavet, and Marie Fabre
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genetic structures ,medicine.diagnostic_test ,Supplementary motor area ,business.industry ,Stimulation ,General Medicine ,Microneurography ,Electroencephalography ,Somatosensory system ,Dorsolateral prefrontal cortex ,medicine.anatomical_structure ,Neurology ,Cutaneous receptor ,Physiology (medical) ,medicine ,Neurology (clinical) ,business ,Neuroscience ,Balance (ability) - Abstract
Introduction Important for balance control, the activation of the cutaneous foot receptors largely depends on the speed and amplitude of the body oscillations during standing. Material and methods Here, we tested the hypothesis that the transmission of cutaneous inputs to the cortex is reduced during prolonged intervals of small body sways due to continued local skin compression and that under such circumstances, central mechanisms trigger large sways to reactivate the cutaneous receptors. We compared the amplitude of the somatosensory cortical potentials (P50-N90) evoked by electric stimulations of the foot sole during either small or large sways in 16 adults that were standing still with the eyes closed. Results We found greater P50-N90 amplitude when the stimulation occurred during large body sways, consistent with an increased sensory transmission. Importantly, body oscillations computed 200 ms prior to large sways had smaller amplitude than intervals that were not followed by large sways. Discussion The hypothesis of a depressed sensory transmission during continued skin compression was supported by our microneurographic recordings showing adaptation/suppression of tactile fibres discharge during continuous pressure applied to the mechanoreceptors. Finally, the hypothesis that large sways during standing correspond to a self-generated functional behaviour to release skin compression is supported by cortical source and EMG analyses showing respectively that large sways were preceded by activation of cortical areas known to be engaged in motor planning (supplementary motor area and dorsolateral prefrontal cortex) and by ankle muscle activations. Together, the present findings provide evidence for an important sensory function of large body sways for balance control.
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- 2019
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39. The involvement of cutaneous receptors in the biological effects of electromagnetic millimeter waves
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Emil Anton, Saulea Gabriela, Saulea Aurel, Carmen Anton, Si. Bruma, and Alin Ciobica
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peripheral nerves terminations ,Chronaxie ,business.industry ,Degranulation ,Stimulation ,Anatomy ,General Biochemistry, Genetics and Molecular Biology ,Nociception ,lcsh:Biology (General) ,Cutaneous receptor ,cutaneous receptors ,Reflex ,Medicine ,Millimeter ,Sciatic nerve ,General Agricultural and Biological Sciences ,business ,Neuroscience ,lcsh:QH301-705.5 ,electromagnetic millimeter waves - Abstract
The involvement of peripheral nerve terminations in the mechanisms of action of electromagnetic millimeter waves (mmW) was assessed. It is currently thought that mmW could be used in noninvasive complementary therapy because of their analgesic effect. However, the mechanisms of their antinociceptive effect and non-ionizing radiation are the subjects of controversy. The mechanisms of interaction of mmW and the cutaneous tissue have not been elucidated. We observed mast cell degranulation at the place of mmW action, a decrease of chronaxie and Turck reflex time, an increase in the number of afferent impulses after sciatic nerve at stimulation, as well as an increase electrocardiogram R-R interval of isolated frog heart after application of mmW. Based on these investigations, we propose that electromagnetic waves of millimeter length modify, through indirect mechanisms, the excitability and reactivity of peripheral nerve terminations.
- Published
- 2014
40. Origin of directionally tuned responses in lower limb muscles to unpredictable upper limb disturbances
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Ali Forghani and Theodore E. Milner
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Sensory Receptors ,Elbow ,lcsh:Medicine ,Social Sciences ,Hands ,Electromyography ,0302 clinical medicine ,Medicine and Health Sciences ,Psychology ,lcsh:Science ,Musculoskeletal System ,Multidisciplinary ,medicine.diagnostic_test ,Arms ,medicine.anatomical_structure ,Bioassays and Physiological Analysis ,Arm ,Upper limb ,Legs ,Sensory Perception ,Anatomy ,Mechanoreceptors ,Muscle Electrophysiology ,Research Article ,Signal Transduction ,Sensory system ,Research and Analysis Methods ,03 medical and health sciences ,Cutaneous receptor ,medicine ,Humans ,Ground reaction force ,Muscle, Skeletal ,Leg ,business.industry ,lcsh:R ,Limbs (Anatomy) ,Electrophysiological Techniques ,Ankles ,Biology and Life Sciences ,030229 sport sciences ,Cell Biology ,Spinal cord ,lcsh:Q ,sense organs ,Ankle ,business ,Neuroscience ,030217 neurology & neurosurgery - Abstract
Unpredictable forces which perturb balance are frequently applied to the body through interaction between the upper limb and the environment. Lower limb muscles respond rapidly to these postural disturbances in a highly specific manner. We have shown that the muscle activation patterns of lower limb muscles are organized in a direction specific manner which changes with lower limb stability. Ankle muscles change their activity within 80 ms of the onset of a force perturbation applied to the hand which is earlier than the onset of changes in ground reaction force, ankle angle or head motion. The latency of the response is sensitive to the perturbation direction. However, neither the latency nor the magnitude of the response is affected by stiffening the arm even though this alters the magnitude and timing of motion of the body segments. Based on the short latency, insensitivity of the change in ankle muscle activation to motion of the body segments but sensitivity to perturbation direction we reason that changes in ankle muscle activation are most likely triggered by sensory signals originating from cutaneous receptors in the hand. Furthermore, evidence that the latency of changes in ankle muscle activation depends on the number of perturbation directions suggests that the neural pathway is not confined to the spinal cord.
- Published
- 2016
41. Improvement of the night sleep quality by electrocutaneous subthreshold stimulation synchronized with the slow wave sleep
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V M Shakhnarovich, A S Bugaev, Yu. V. Gulyaev, V V Dementienko, and P A Indursky
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0301 basic medicine ,Male ,medicine.medical_specialty ,Sleep, REM ,Stimulation ,Electroencephalography ,Audiology ,Anxiety ,General Biochemistry, Genetics and Molecular Biology ,03 medical and health sciences ,0302 clinical medicine ,Cutaneous receptor ,Medicine ,Animals ,Humans ,Slow-wave sleep ,General Immunology and Microbiology ,medicine.diagnostic_test ,Subthreshold conduction ,business.industry ,Depression ,General Medicine ,Sleep in non-human animals ,030104 developmental biology ,Duration (music) ,Female ,medicine.symptom ,General Agricultural and Biological Sciences ,business ,Sleep ,030217 neurology & neurosurgery - Abstract
Changes in sleep characteristics were studied under the non-wake-up stimulation with current pulses of less than 1 μA on average, applied to the palmar surface skin receptors during Δ-sleep. A significant increase in duration of the first and second cycles of deep sleep has been found, as well as a shorter latent period before the Δ-sleep onset and a longer time of the rapid sleep (REM phase). The sleep structure improvement was accompanied by the reduced reactive anxiety and depression and an increase in subjective physical efficiency.
- Published
- 2016
42. The Reflex Circuitry Originating from the Cutaneous Receptors of the Hand to the First Dorsal Interosseus Muscle
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Mehmet Cemal Kahya and Kemal S. Türker
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Dorsum ,Motor unit ,Hand muscles ,business.industry ,Cutaneous receptor ,Duration (music) ,Anesthesia ,Reflex ,Medicine ,Silent period ,business ,Analysis method - Abstract
In this study, we aimed to use both the probability- and frequency-based analyses methods simultaneously to examine cutaneous silent period induced by strong electrical currents. Subjects were asked to contract their hand muscles so that single motor unit discharged at a rate of approximately 8 Hz. Strong electrical stimuli were delivered to the back of the hand and induced cutaneous silent period in all units. It was found that the duration of the cutaneous silent period (CSP) was significantly longer when the same data were analysed using frequency-based analysis method compared with the probability-based methods.
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- 2016
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43. A soft ankle brace increases soleus Hoffman reflex amplitude but does not modify presynaptic inhibition during upright standing
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Frédérique Hintzy, Thomas Lapole, Sébastien Pavailler, Nicolas Horvais, Nicolas Forestier, Laboratoire Interuniversitaire de Biologie de la Motricité ( LIBM ), Université Claude Bernard Lyon 1 ( UCBL ), Université de Lyon-Université de Lyon-Université Jean Monnet [Saint-Étienne] ( UJM ) -Université Savoie Mont Blanc ( USMB [Université de Savoie] [Université de Chambéry] ), SALOMON Corporation, Laboratoire Interuniversitaire de Biologie de la Motricité (LIBM ), Université Claude Bernard Lyon 1 (UCBL), and Université de Lyon-Université de Lyon-Université Jean Monnet [Saint-Étienne] (UJM)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])
- Subjects
musculoskeletal diseases ,Adult ,Male ,medicine.medical_specialty ,Posture ,Biophysics ,Electromyography ,H-Reflex ,[ SDV.NEU.PC ] Life Sciences [q-bio]/Neurons and Cognition [q-bio.NC]/Psychology and behavior ,03 medical and health sciences ,Young Adult ,0302 clinical medicine ,Physical medicine and rehabilitation ,Femoral nerve ,Cutaneous receptor ,medicine ,Humans ,Orthopedics and Sports Medicine ,Tibial nerve ,Muscle, Skeletal ,ComputingMilieux_MISCELLANEOUS ,Soleus muscle ,Motor Neurons ,Braces ,medicine.diagnostic_test ,[SDV.NEU.PC]Life Sciences [q-bio]/Neurons and Cognition [q-bio.NC]/Psychology and behavior ,business.industry ,Rehabilitation ,030229 sport sciences ,Equipment Design ,musculoskeletal system ,Brace ,Electric Stimulation ,medicine.anatomical_structure ,Ankle ,H-reflex ,Tibial Nerve ,business ,human activities ,Mechanoreceptors ,030217 neurology & neurosurgery ,Ankle Joint - Abstract
External ankle supports, such as ankle braces, may improve postural stability by stimulating cutaneous receptors. It remains unknown whether these supports have an effect on the posture central regulation. The aim of this study was to determine the effect of wearing a soft ankle brace on soleus H-reflex amplitude and presynaptic inhibition during standing. Sixteen subjects stood on a rigid floor with their eyes opened, either barefoot or wearing a soft ankle brace. H-reflex amplitude was measured on the soleus muscle by stimulating the tibial nerve electrically. Modulation of presynaptic inhibition was assessed by conditioning the H-reflex with fibular nerve (D1 inhibition) and femoral nerve (heteronymous facilitation) electrical stimulations. The unconditioned H-reflex amplitude was significantly greater when wearing the ankle brace than barefoot, whereas D1 and HF conditioned soleus H-reflex did not differ significantly between bracing conditions. These results suggest that the ankle brace increased the soleus motoneuron excitability without altering presynaptic mechanisms, potentially because of increased cutaneous mechanoreceptors afferent signals provided by the soft ankle brace.
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- 2016
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44. Functional and structural organization of the forelimb representation in cuneate nucleus in rat
- Author
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Cheng X. Li, Robert S. Waters, and Qiuhong Yang
- Subjects
Biology ,Wrist ,Electron Transport Complex IV ,Cuneate fasciculus ,Forearm ,Cutaneous receptor ,Forelimb ,medicine ,Animals ,Electrodes ,Molecular Biology ,Skin ,Human Body ,Afferent Pathways ,Brain Mapping ,Medulla Oblongata ,General Neuroscience ,Anatomy ,Electric Stimulation ,Rats ,body regions ,medicine.anatomical_structure ,Spinal Cord ,Dorsal column nuclei ,Neurology (clinical) ,Brainstem ,Cuneate nucleus ,Neuroscience ,Developmental Biology - Abstract
We examined the physiological representation of the forelimb in the cuneate nucleus (CN) of forelimb-intact young adult rats (n = 38) as the first part in a series of studies aimed at understanding the possible role that CN plays in delayed cortical reorganization that follows forelimb amputation. Metabolic labeling with cytochrome oxidase (CO) and electrophysiological mapping were used to examine the relationship between the structural and functional organization of CN. CN is a cylinder-shaped structure that lies bilaterally in the brainstem and extends nearly 4 mm in the rostrocaudal direction. The forelimb is represented along the rostrocaudal extent. CN contains three zones; the rostral and caudal zones receive input largely from deep muscle and joint receptors and a middle zone, in the vicinity of the obex, receives input primarily from cutaneous receptors in the skin. The middle zone is somatotopically organized with the glabrous digits represented centrally, bordered on the medial side by ulnar wrist, ulnar forearm, and posterior upper arm representations; on the lateral side by radial wrist, radial forearm, and anterior upper arm representations; and on dorsal side by the dorsal digits and dorsal hand. The middle zone also contains well-defined CO-filled glomerular structures, called barrelettes, which are located within a homogenously stained field. The barrelettes are associated with the representation of the glabrous digits, with D5 represented most dorsal followed sequentially in a ventral-to-lateral direction by the representation of D4, D3, D2, and D1. The digit representations are topographically organized with the distal digit surface represented laterally with respect to the more medially lying proximal digit surface. The digit and palmar pads are also represented by barrelettes located on the medial side of CN. In contrast, the dorsal digit surfaces are represented dorsally and the dorsal hand is represented directly beneath the cuneate fasciculus, in a region devoid of barrelettes. The representations of the ulnar and radial wrist, forearm, and upper arm also lie within the homogeneously stained field in CN. The forelimb representation is bordered on the medial side by representation of trunk and hindlimb, and on the lateral side by representation of shoulder, ear, and head. While the present findings support and extend previous electrophysiological and anatomical studies of CN in the rat, they also provide a detailed physiological description of the functional organization of CN that is necessary for subsequent understanding of the functional reorganization of CN that may result following forelimb amputation.
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- 2012
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45. The upright posture improves plantar stepping and alters responses to serotonergic drugs in spinal rats
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Henryk Majczyński, Yue Dai, Urszula Sławińska, and Larry M. Jordan
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medicine.medical_specialty ,Physiology ,musculoskeletal, neural, and ocular physiology ,Quipazine ,Stimulation ,Hindlimb ,Anatomy ,medicine.disease ,Serotonergic ,Locomotor activity ,body regions ,Physical medicine and rehabilitation ,Cutaneous receptor ,medicine ,Treadmill ,Psychology ,Spinal cord injury ,medicine.drug - Abstract
Recent studies on the restoration of locomotion after spinal cord injury have employed robotic means of positioning rats above a treadmill such that the animals are held in an upright posture and engage in bipedal locomotor activity. However, the impact of the upright posture alone, which alters hindlimb loading, an important variable in locomotor control, has not been examined. Here we compared the locomotor capabilities of chronic spinal rats when placed in the horizontal and upright postures. Hindlimb locomotor movements induced by exteroceptive stimulation (tail pinching) were monitored with video and EMG recordings. We found that the upright posture alone significantly improved plantar stepping. Locomotor trials using anaesthesia of the paws and air stepping demonstrated that the cutaneous receptors of the paws are responsible for the improved plantar stepping observed when the animals are placed in the upright posture. We also tested the effectiveness of serotonergic drugs that facilitate locomotor activity in spinal rats in both the horizontal and upright postures. Quipazine and (±)-8-hydroxy-2-(dipropylamino)tetralin hydrobromide (8-OH-DPAT) improved locomotion in the horizontal posture but in the upright posture either interfered with or had no effect on plantar walking. Combined treatment with quipazine and 8-OH-DPAT at lower doses dramatically improved locomotor activity in both postures and mitigated the need to activate the locomotor CPG with exteroceptive stimulation. Our results suggest that afferent input from the paw facilitates the spinal CPG for locomotion. These potent effects of afferent input from the paw should be taken into account when interpreting the results obtained with rats in an upright posture and when designing interventions for restoration of locomotion after spinal cord injury.
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- 2012
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46. Sensibility of the Ear After Otoplasty
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Fabio de Freitas Busnardo, Pedro Soler Coltro, Helio R.N. Alves, Samuel T Gallafrio, and Marcus Castro Ferreira
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Adult ,Male ,Adolescent ,Sensory system ,Cosmetic Techniques ,Vibration ,Young Adult ,Vibration perception ,Cutaneous receptor ,Skin Physiological Phenomena ,Pressure ,Humans ,Medicine ,Thermosensing ,Sensibility ,Prospective Studies ,Ear, External ,Great auricular nerve ,integumentary system ,business.industry ,Cervical plexus ,Anatomy ,Touch ,Female ,Surgery ,business ,Otoplasty ,Follow-Up Studies - Abstract
Changes in skin sensibility occur in various postoperative plastic surgeries, especially when they involve major skin and subcutaneous dissection. There were no studies so far that objectively compared changes of ear sensibility. This prospective study was conducted to compare ear sensibility before and after otoplasty. Patients with prominent ears (n = 15) underwent bilateral otoplasty. Ear tactile sensibility was tested preoperatively and 6 and 12 months after surgery by Pressure Specified Sensory Device, an apparatus that quantifies cutaneous pressure sensation (g/mm(2)). Comparison between preoperative and 6-months postoperative results indicated an increment on mean skin pressure thresholds; however, mean thresholds between pre- and 12 months postoperative period were similar. Vibratory and hot/cold sensibility did not present any difference during this period. This is the first comparative assessment of ear tactile sensibility using quantitative methods. After otoplasty, initially there was reduction in an ear tactile sensibility, followed by a return to levels similar to preoperative sensibility.
- Published
- 2012
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47. Mechanobiology of scarring
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Rei Ogawa
- Subjects
Pathology ,medicine.medical_specialty ,Chemistry ,Hydrostatic pressure ,Dermatology ,Cell biology ,Mechanoreceptor ,Mechanobiology ,medicine.anatomical_structure ,Cutaneous receptor ,medicine ,Nociceptor ,Surgery ,Mechanosensitive channels ,Mechanotransduction ,Sensory nerve - Abstract
The mechanophysiological conditions of injured skin greatly influence the degree of scar formation, scar contracture, and abnormal scar progression/generation (e.g., keloids and hypertrophic scars). It is important that scar mechanobiology be understood from the perspective of the extracellular matrix and extracellular fluid, in order to analyze mechanotransduction pathways and develop new strategies for scar prevention and treatment. Mechanical forces such as stretching tension, shear force, scratch, compression, hydrostatic pressure, and osmotic pressure can be perceived by two types of skin receptors. These include cellular mechanoreceptors/mechanosensors, such as cytoskeleton (e.g., actin filaments), cell adhesion molecules (e.g., integrin), and mechanosensitive (MS) ion channels (e.g., Ca(2+) channel), and sensory nerve fibers (e.g., MS nociceptors) that produce the somatic sensation of mechanical force. Mechanical stimuli are received by MS nociceptors and signals are transmitted to the dorsal root ganglia that contain neuronal cell bodies in the afferent spinal nerves. Neuropeptides are thereby released from the peripheral terminals of the primary afferent sensory neurons in the skin, modulating scarring via skin and immune cell functions (e.g., cell proliferation, cytokine production, antigen presentation, sensory neurotransmission, mast cell degradation, vasodilation, and increased vascular permeability under physiological or pathophysiological conditions). Mechanoreceptor or MS nociceptor inhibition and mechanical force reduction should propel the development of novel methods for scar prevention and treatment.
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- 2011
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48. Relationship between foot sensation and standing balance in patients with multiple sclerosis
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Arzu Guclu Gunduz, Meral Bosnak Guclu, Seyit Citaker, Bijen Nazliel, Defne Kaya, and Ceyla Irkec
- Subjects
Adult ,Male ,medicine.medical_specialty ,Heel ,Sensation ,Biophysics ,Vibration ,Multiple Sclerosis, Relapsing-Remitting ,Physical medicine and rehabilitation ,Cutaneous receptor ,Sensory threshold ,medicine ,Humans ,Orthopedics and Sports Medicine ,Postural Balance ,Balance (ability) ,Expanded Disability Status Scale ,Foot ,Multiple sclerosis ,Rehabilitation ,medicine.disease ,medicine.anatomical_structure ,Touch ,Sensory Thresholds ,Female ,Psychology ,Foot (unit) - Abstract
The aims of the present study were to investigate the relationship between the foot sensations and standing balance in patients with Multiple Sclerosis (MS) and find out the sensation, which best predicts balance. Twenty-seven patients with MS (Expanded Disability Status Scale 1-3.5) and 10 healthy volunteers were included. Threshold of light touch-pressure, duration of vibration, and distance of two-point discrimination of the foot sole were assessed. Duration of static one-leg standing balance was measured. Light touch-pressure, vibration, two-point discrimination sensations of the foot sole, and duration of one-leg standing balance were decreased in patients with MS compared with controls (p < 0.05). Sensation of the foot sole was related with duration of one-leg standing balance in patients with MS. In the multiple regression analysis conducted in the 27 MS patients, 47.6% of the variance in the duration of one-leg standing balance was explained by two-point discrimination sensation of the heel (R(2) = 0.359, p = 0.001) and vibration sensation of the first metatarsal head (R(2) = 0.118, p = 0.029). As the cutaneous receptors sensitivity decreases in the foot sole the standing balance impairs in patients with MS. Two-point discrimination sensation of the heel and vibration sensation of the first metatarsal head region are the best predictors of the static standing balance in patients with MS. Other factors which could be possible to predict balance and effects of sensorial training of foot on balance should be investigated. (C) 2011 Elsevier B.V. All rights reserved.
- Published
- 2011
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49. Mislocalization of near-threshold tactile stimuli in humans: a central or peripheral phenomenon?
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Anja Wühle, Effi Eisele, Christoph Braun, Maik C. Stüttgen, Gianpaolo Demarchi, and Cornelius Schwarz
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Lateral inhibition ,Cutaneous receptor ,General Neuroscience ,Sensory threshold ,Touch Perception ,Stimulation ,Stimulus (physiology) ,Somatosensory system ,Psychology ,Neuroscience ,Peripheral - Abstract
Principles of brain function can be disclosed by studying their limits during performance. Tactile stimuli with near-threshold intensities have been used to assess features of somatosensory processing. When stimulating fingers of one hand using near-threshold intensities, localization errors are observed that deviate significantly from responses obtained by guessing - incorrectly located stimuli are attributed more often to fingers neighbouring the stimulated one than to more distant fingers. Two hypotheses to explain the findings are proposed. The 'central hypothesis' posits that the degree of overlap of cortical tactile representations depends on stimulus intensity, with representations less separated for near-threshold stimuli than for suprathreshold stimuli. The 'peripheral hypothesis' assumes that systematic mislocalizations are due to activation of different sets of skin receptors with specific thresholds. The present experiments were designed to decide between the two hypotheses. Taking advantage of the frequency tuning of somatosensory receptors, their contribution to systematic misclocalizations was studied. In the first experiment, mislocalization profiles were investigated using vibratory stimuli with frequencies of 10, 20 and 100 Hz. Unambiguous mislocalization effects were only obtained for the 10-Hz stimulation, precluding the involvement of Pacinian corpuscles in systematic mislocalization. In the second experiment, Pacinian corpuscles were functionally eliminated by applying a constant 100-Hz vibratory masking stimulus together with near-threshold pulses. Despite masking, systematic mislocation patterns were observed rendering the involvement of Pacinian corpuscles unlikely. The results of both experiments are in favor of the 'central hypothesis' assuming that the extent of overlap in somatosensory representations is modulated by stimulus intensity.
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- 2010
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50. Functional Coupling Between Motor and Sensory Nerves Through Contraction of Sphincters in the Pudendal Area of the Female Cat
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José Guadalupe Raya, Pablo Rogelio Hernández, E. J. Muñoz-Martínez, and Roberto Lagunes-Córdoba
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Contraction (grammar) ,Sensory Receptor Cells ,Physiology ,Movement ,Action Potentials ,Anal Canal ,Sensory system ,Cutaneous receptor ,Physical Stimulation ,Skin Physiological Phenomena ,Reflex ,Pressure ,medicine ,Animals ,Receptor ,Motor Neurons ,Chemistry ,General Neuroscience ,Body movement ,Axons ,Electric Stimulation ,Touch Perception ,Vagina ,Cats ,Female ,medicine.symptom ,Microelectrodes ,Neuroscience ,Muscle Contraction ,Muscle contraction - Abstract
The question of whether skin receptors might help in the perception of muscle contraction and body movement has not been settled. The present study gives direct evidence of skin receptor firing in close coincidence with the contraction of the vaginal and anal sphincters. The distal stump of the sectioned motor pudendal nerve was stimulated. Single shocks induced a wavelike increase in the lumen pressure of the distal vagina and the anal canal, as well as constriction of the vaginal introitus and the anus. The constriction pulls on and moves the surrounding skin, which was initially detected visually. In the present experiments, a thin strain gauge that pressed on the skin surface detected its displacement. Single shocks to the motor nerve induced a wave of skin movement with maximal amplitude at 5 mm from the anus and propagated with decrement beyond 35 mm. The peripheral terminals of the sensory pudendal nerve and the posterior femoral nerve supply the skin that moves. Sensory axons from both nerves fired in response to both tactile stimulation and the skin movement produced by the constriction of the orifices (motor–sensory coupling). In cats with all nerves intact, a single shock to the sensory nerves induced reflex waves of skin movement and lumen pressure (sensory–motor coupling). Both couplings provide evidence for a feedforward action that might help to maintain the female posture during mating and to the perception of muscle contraction.
- Published
- 2010
- Full Text
- View/download PDF
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