913 results on '"visual sensitivity"'
Search Results
52. Tobacco Use Decreases Visual Sensitivity in Schizophrenia
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Thiago M. P. Fernandes, Michael J. Oliveira de Andrade, Jessica B. Santana, Renata M. Toscano Barreto Lyra Nogueira, and Natanael A. dos Santos
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schizophrenia ,perception ,visual sensitivity ,tobacco addiction ,smoking ,public health ,Psychology ,BF1-990 - Abstract
Smoking prevalence in patients who are diagnosed with schizophrenia (SCZ) is higher than in the general population. Chronic tobacco use in SCZ patients may reduce the side effects of antipsychotic drugs, thus serving as a self-medication for such side effects. Understanding the ways in which chronic tobacco use influences visual sensitivity has clinical implications, which may serve as a tool for non-invasively diagnosing early-stage visual processing deficits. The present study evaluated the effects of chronic tobacco use on visual sensitivity in SCZ patients. Our purpose was to provide new directions for future research, mainly psychophysical and electrophysiological studies. In the present study, 40 smoker controls (SC), 20 SCZ tobacco users, and 20 SCZ tobacco nonusers were recruited from the Psychosocial Care Center. Visual sensitivity was compared between both SCZ groups and the SC group. Patients with SCZ who were chronic tobacco users presented lower visual sensitivity for chromatic (p < 0.001) and achromatic (p < 0.001) stimuli compared with the other groups. Our findings highlight the need to evaluate possible addictive behavior in patients with SCZ, which may contribute to public policies that seek to improve the quality of life of SCZ patients and their families.
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- 2018
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53. A Novel Rate Control Algorithm for H.264/AVC Based on Human Visual System
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Zhu, Jiangying, Yu, Mei, Zheng, Qiaoyan, Peng, Zongju, Shao, Feng, Li, Fucui, Jiang, Gangyi, Hutchison, David, Series editor, Kanade, Takeo, Series editor, Kittler, Josef, Series editor, Kleinberg, Jon M., Series editor, Mattern, Friedemann, Series editor, Mitchell, John C., Series editor, Naor, Moni, Series editor, Nierstrasz, Oscar, Series editor, Pandu Rangan, C., Series editor, Steffen, Bernhard, Series editor, Sudan, Madhu, Series editor, Terzopoulos, Demetri, Series editor, Tygar, Doug, Series editor, Vardi, Moshe Y., Series editor, Weikum, Gerhard, Series editor, and Ho, Yo-Sung, editor
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- 2012
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54. A Study of Expressinging Symbolic Sculptures of Roundabout Considering the Visual Sensitivity of Drivers - Based on Symbolic Sculptures Installed at Small-size Roundabout in Korea from 2010 to 2021
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Jun Ho Kwon
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Sculpture ,media_common.quotation_subject ,Roundabout ,Art ,Visual sensitivity ,media_common ,Visual arts - Published
- 2021
55. Visual performance and reaction time measures for object-based attention
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Shurygina, Olga and Rolfs, Martin
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object-based attantion ,visual sensitivity ,Life Sciences ,exogenous attention - Abstract
We will explore spread of covert exogenous attention along objects, in a double-rectangle cueing paradigm by measuring response time and performance in a visual discrimination task. We will compare the sensitivity of these measures for targets given different levels of noise. In their classical study, Egly, Driver & Rafal (1994) showed that visual attention spreads along attended objects (rectangles) by measuring the simple response time to visual probe stimuli. Since then, their double-rectangle cueing paradigm was extensively used in research studying different aspects of object-based attention (e.g., Lamy & Egeth, 2002; Jurissen, Roelfsema, 2016; McCarley et al., 2002; Theeuwes & Mathot, 2010; Pilz et al., 2012; Drummond & Shomstein, 2010) In most of these studies the main measure of the attention was a response time in a simple detection task. The question whether the spread of attention along the object can be observed in increased visual sensitivity (measured as improved performance in a visual discrimination task) remains unclear. In the current experiment, we have three aims. Our first aim is to compare two well-established methods of measuring visual attention — response time and performance in a visual discrimination task — in order to estimate which of these measures is more sensitive for object-based attention depending on the signal to noise ratio of the stimulus that is to be detected (henceforth, probe). The second aim of our study to bring the measurement of object-based attention closer to natural vision in real-world scenes. That’s why we will probe attention in different signal-to-noise ratios (SNRs) as the objects in real life will have different textures. Finally, the majority of the above mentioned studies used a hybrid cue that had both exogenous (it was a sudden onset flash in the visual periphery) and endogenous components (the probe was presented more often at the cued location than elsewhere). We will make the cue irrelevant for the task, allowing us to measure the spread of purely automatic, exogenous attention. In our previous study we showed increased visual sensitivity at locations that were perceptually grouped with a location that was attended as the saccade target (Shurygina et al., 2020 – under review). In the current experiment, we will use grouping features from that study (color, pattern of the movement) to strengthen the perception of the objects as separate items.
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- 2022
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56. Visual Behavior and Visual Sensitivity of Nautilus pompilius
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Muntz, W. R. A., Landman, Neil H., editor, Harries, Peter J., editor, and Saunders, W. Bruce, editor
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- 2010
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57. Intrasaccadic Motion: Neural Evidence for Saccadic Suppression and Postsaccadic Enhancement
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Ibbotson, Michael R., Ilg, Uwe J., editor, and Masson, Guillaume S., editor
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- 2010
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58. Tobacco Use Decreases Visual Sensitivity in Schizophrenia.
- Author
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Fernandes, Thiago M. P., Andrade, Michael J. Oliveira de, Santana, Jessica B., Nogueira, Renata M. Toscano Barreto Lyra, and Santos, Natanael A. dos
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TOBACCO & health ,VISUAL perception ,SCHIZOPHRENIA ,PUBLIC health ,DISEASE prevalence - Abstract
Smoking prevalence in patients who are diagnosed with schizophrenia (SCZ) is higher than in the general population. Chronic tobacco use in SCZ patients may reduce the side effects of antipsychotic drugs, thus serving as a self-medication for such side effects. Understanding the ways in which chronic tobacco use influences visual sensitivity has clinical implications, which may serve as a tool for non-invasively diagnosing early-stage visual processing deficits. The present study evaluated the effects of chronic tobacco use on visual sensitivity in SCZ patients. Our purpose was to provide new directions for future research, mainly psychophysical and electrophysiological studies. In the present study, 40 smoker controls (SC), 20 SCZ tobacco users, and 20 SCZ tobacco nonusers were recruited from the Psychosocial Care Center. Visual sensitivity was compared between both SCZ groups and the SC group. Patients with SCZ who were chronic tobacco users presented lower visual sensitivity for chromatic (p < 0.001) and achromatic (p < 0.001) stimuli compared with the other groups. Our findings highlight the need to evaluate possible addictive behavior in patients with SCZ, which may contribute to public policies that seek to improve the quality of life of SCZ patients and their families. [ABSTRACT FROM AUTHOR]
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- 2018
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59. The Attraction of Stored Grain Pests Toward Various Colour Surfaces
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Shafique Ahmed Memon, Muhammad Abuzar Jaffar, Gulkhanda Parwaiz, Ghulam Khaliq, Intazar Ali, and Ghulam Ali Bugti
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genetic structures ,Stored grain ,ved/biology ,fungi ,ved/biology.organism_classification_rank.species ,Biology ,biology.organism_classification ,Visual sensitivity ,Attraction ,Retinal image ,Horticulture ,Pigment ,visual_art ,visual_art.visual_art_medium ,Red flour beetle ,Callosobruchus chinensis ,Green colour - Abstract
Colour vision is common phenomenon in living animals, but varies in insect species, depending on their vision sensitivity and photoreceptors involved. The sensitivity of the photoreceptor is determined through the absorption of visual colour pigments expressed. Photoreceptors are involved in filtering pigments, transverse wavelength, retinal image and colour signals. We have evaluated the colour attraction of two important stored grains insects, Red flour beetle (Tribolium castaneum H) and Pulse beetle (Callosobruchus chinensis L) to determine their visual sensitivity toward various colour surfaces. The data was recorded after 24hrs of releasing the insects in a chamber in which various colour surfaces were provided. The results showed that the T. castaneum was highly attracted toward green colour with maximum (17.3%) and (8.7%) of insects observed outside and inside the bags respectively. Whereas, minimum (4.3%) and (3.0%) T. castaneum found outside and inside the blue colour bags respectively. Similarly, C. chinensis was greatly attracted toward blue colour with the maximum (16.0%) and (7.7%) insects found attached outside and inside the bags respectively. Whereas, minimum (9.0%) and (2.0%) C. chinensis were recorded outside and inside the black colour bags respectively.
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- 2021
60. 34‐3: Visual Sensitivity to 'Perfect' Black
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Michael J. Murdoch, Fu Jiang, Ben Bodner, and Susan P. Farnand
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Optics ,business.industry ,Computer science ,Organic Chemistry ,Glare (vision) ,Sensitivity (control systems) ,business ,Biochemistry ,Visual sensitivity - Published
- 2021
61. Retinal OFF ganglion cells allow detection of quantal shadows at starlight
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Johan Westö, Nataliia Martyniuk, Sanna Koskela, Tuomas Turunen, Santtu Pentikäinen, Petri Ala-Laurila, Department of Neuroscience and Biomedical Engineering, University of Helsinki, Aalto-yliopisto, Aalto University, Ala-Laurila Lab, Molecular and Integrative Biosciences Research Programme, Organismal and Evolutionary Biology Research Programme, and Biosciences
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Retinal Ganglion Cells ,retina ,vision ,ON pathway ,General Biochemistry, Genetics and Molecular Biology ,Retina ,ganglion cells ,PATHWAY ,Mice ,SIGNALS ,NIGHT ,Retinal Rod Photoreceptor Cells ,visual sensitivity ,Animals ,photon detection ,visually guided behavior ,CHANNELS ,ABSOLUTE THRESHOLD ,Darkness ,VISION ,decrement ,Mice, Inbred CBA ,MOUSE EYE ,1182 Biochemistry, cell and molecular biology ,retinal circuit ,SENSITIVITY ,General Agricultural and Biological Sciences ,BEHAVIOR ,Photic Stimulation ,OFF pathway ,RESPONSES - Abstract
openaire: EC/H2020/713645/EU//BioMEP Funding Information: We thank Drs. Kristian Donner, Greg Schwartz, Gabriel Peinado, and Christophe Ribelayga for valuable comments on the manuscript; Matthew Dunkerley and Sathish Narayanan for the design of the data acquisition software; Dr. Martta Viljanen for technical assistance with the design of the water maze; and Mr. Sami Minkkinen for technical assistance with the design of the patch rig. Support was provided by the Academy of Finland (296269 and 305834 to P.A.-L.); the Aalto Brain Centre (J.W.); Svenska kulturfonden (J.W.); the Finnish Society of Sciences and Letters (J.W.); the European Union's Horizon 2020 research and innovation programme (Marie Sklodowska-Curie grant 713645 to N.M.); the Doctoral programme Brain & Mind, University of Helsinki (S.K.); the Finnish Cultural Foundation (S.K.); the Ella and Georg Ehrnrooth Foundation (T.T.); the Oskar Öflund Foundation (T.T.); and the Finnish Foundation for Technology Promotion (T.T.). We acknowledge the computational resources provided by the Aalto Science-IT Project. Parts of Figure 1 and 4 were adapted from https://biorender.com. J.W. S.K. and P.A.-L. designed the experiments. T.T. developed the methodology for markerless mouse tracking. T.T. and S.K. set up the water maze used for behavioral experiments, and S.P carried out behavioral experiments. S.K. and S.P. collected and analyzed pupil data. N.M. carried out RGC experiments. J.W. S.K. and S.P. analyzed data. J.W. S.K. and P.A.-L wrote the MS. P.A.-L. is a founder and shareholder of Quantal Vision Technologies. T.T. and P.A.-L. have the following patents related to “a method for performing behavioral experiments with rodents”: FI127666B & US10706287B2. Perception of light in darkness requires no more than a handful of photons, and this remarkable behavioral performance can be directly linked to a particular retinal circuit—the retinal ON pathway. However, the neural limits of shadow detection in very dim light have remained unresolved. Here, we unravel the neural mechanisms that determine the sensitivity of mice (CBA/CaJ) to light decrements at the lowest light levels by measuring signals from the most sensitive ON and OFF retinal ganglion cell types and by correlating their signals with visually guided behavior. We show that mice can detect shadows when only a few photon absorptions are missing among thousands of rods. Behavioral detection of such “quantal” shadows relies on the retinal OFF pathway and is limited by noise and loss of single-photon signals in retinal processing. Thus, in the dim-light regime, light increments and decrements are encoded separately via the ON and OFF retinal pathways, respectively.
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- 2022
62. Motion Perception Based Adaptive Quantization for Video Coding
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Tang, Chih-Wei, Hutchison, David, editor, Kanade, Takeo, editor, Kittler, Josef, editor, Kleinberg, Jon M., editor, Mattern, Friedemann, editor, Mitchell, John C., editor, Naor, Moni, editor, Nierstrasz, Oscar, editor, Pandu Rangan, C., editor, Steffen, Bernhard, editor, Sudan, Madhu, editor, Terzopoulos, Demetri, editor, Tygar, Dough, editor, Vardi, Moshe Y., editor, Weikum, Gerhard, editor, Ho, Yo-Sung, editor, and Kim, Hyoung Joong, editor
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- 2005
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63. Characteristics of visual sensitivity in familial cortical myoclonic tremor and epilepsy
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Yujia Cao, Wenjuan Zhang, Xiaoli Wang, Jiang Zhu, Yonghong Liu, Jin-Xiang Wang, and Bi Wang
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medicine.medical_specialty ,genetic structures ,medicine.diagnostic_test ,business.industry ,Electroencephalography ,Epilepsies, Myoclonic ,Video sequence ,General Medicine ,Audiology ,medicine.disease ,Visual sensitivity ,eye diseases ,Pedigree ,Epilepsy ,Neurology ,Neuroimaging ,Tremor ,medicine ,Reflex ,Humans ,In patient ,Photosensitivity Disorders ,Neurology (clinical) ,business - Abstract
The aim of the study was to describe the electroclinical features of visual sensitivity in patients with familial cortical myoclonic tremor and epilepsy. We searched the EEG database using the terms "familial cortical myoclonic tremor and epilepsy" and "visual sensitivity" over a seven-year period from March 2013 to April 2020 in the Xijing hospital, Xi'an, China. The inclusion criteria were demonstrable electroclinical visual sensitivity in the form of eye-opening sensitivity, eye-closure sensitivity, eyes-closed sensitivity and photosensitivity. Clinical, EEG and imaging records of patients were screened, and subsequently, detailed analysis of their data was undertaken. We enrolled six patients with visual sensitivity, five of whom suffered with rare generalized tonic-clonic seizures. Neuroimaging was negative in all cases. All patients demonstrated photosensitivity; eye-opening sensitivity associated with cortical myoclonic in one patient, eyes-closed sensitivity associated with cortical myoclonic tremor status in three patients, and eye-closure sensitivity in two patients. At the last follow-up visit, cortical myoclonic tremor and epilepsy in all patients was well controlled with first-line treatment. Visual sensitivity is therefore likely to be an important reflex trait in some patients with familial cortical myoclonic tremor and epilepsy, and should be routinely evaluated in order to better define the electroclinical features in FCMTE syndrome. [Published with video sequences].
- Published
- 2021
64. Short-wavelength visual sensitivity and sexual differences in plumage colouration of ovenbirds (Aves: Furnariinae)
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Ana S. Barreira, Cecilia Kopuchian, Pablo L. Tubaro, Elisabet Vilacoba, and Muir D. Eaton
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0106 biological sciences ,Ovenbird ,genetic structures ,Dichromatism ,biology ,Zoology ,biology.organism_classification ,010603 evolutionary biology ,01 natural sciences ,Visual sensitivity ,010605 ornithology ,Synallaxis spixi ,Plumage ,Clade ,Sexual difference ,Phleocryptes melanops - Abstract
Ovenbirds represent a clade of exclusively Neotropical birds that are exceptionally diverse, despite their rather dull, melanin-based plumage. In general, sexes are considered monomorphic in size and colour, but several authors have reported females of some species within this family as being slightly paler than their conspecific counterparts. Our aim was to assess levels of sexual dichromatism in a set of ovenbird species representing a diversity of genera and plumage patterns; Furnarius rufus, Phleocryptes melanops, Synallaxis spixi and Schoeniophylax phryganophilus. For each species, we quantified sexual differences in brightness and colouration among 8–10 different plumage regions through modelling avian perceptual colour-space distances. To best inform our visual modelling parameters, we successfully sequenced the SWS1 gene fragment (associated with short-wavelength, including ultraviolet, visual sensitivity in birds) for one species, P. melanops, and found it possessed an amino acid sequence consistent with the VS-type SWS1 visual system. This provides further evidence supporting the presence of VS-sensitive opsin in ovenbirds. Among all four species, females were consistently brighter than males in at least one plumage patch, but chromatic colour differences between sexes were significant only for the throat patches of Schoeniophylax phryganophilus. Overall, we interpret ovenbirds to exhibit very low levels of sexual dichromatism, manifest mainly by achromatic colour differences.
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- 2021
65. Upper limb exercise with physical and virtual robots: Visual sensitivity affects task performance
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Agnieszka Wykowska, Cesco Willemse, Pauline Chevalier, Valentina Vasco, Ugo Pattacini, Vadim Tikhanoff, and Davide De Tommaso
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0209 industrial biotechnology ,medicine.medical_specialty ,Technology ,Cognitive Neuroscience ,medicine.medical_treatment ,socially assistive robot ,Virtual agent ,02 engineering and technology ,Task (project management) ,rehabilitation ,Behavioral Neuroscience ,020901 industrial engineering & automation ,Physical medicine and rehabilitation ,Developmental Neuroscience ,Artificial Intelligence ,medicine ,0501 psychology and cognitive sciences ,050107 human factors ,Rehabilitation ,Sensory sensitivity ,05 social sciences ,Visual sensitivity ,Human-Computer Interaction ,medicine.anatomical_structure ,Upper limb ,Robot ,Psychology ,virtual agent ,sensory sensitivity - Abstract
We investigated the influence of visual sensitivity on the performance of an imitation task with the robot R1 in its virtual and physical forms. Virtual and physical embodiments offer different sensory experience to the users. As all individuals respond differently to their sensory environment, their sensory sensitivity may play a role in the interaction with a robot. Investigating how sensory sensitivity can influence the interactions appears to be a helpful tool to evaluate and design such interactions. Here we asked 16 participants to perform an imitation task, with a virtual and a physical robot under conditions of full and occluded visibility, and to report the strategy they used to perform this task. We asked them to complete the Sensory Perception Quotient questionnaire. Sensory sensitivity in vision predicted the participants’ performance in imitating the robot’s upper limb movements. From the self-report questionnaire, we observed that the participants relied more on visual sensory cues to perform the task with the physical robot than on the virtual robot. From these results, we propose that a physical embodiment enables the user to invest a lower cognitive effort when performing an imitation task over a virtual embodiment. The results presented here are encouraging that following this line of research is suitable to improve and evaluate the effects of the physical and virtual embodiment of robots for applications in healthy and clinical settings.
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- 2021
66. GIS-Based Multi-Criteria Assessment and Seasonal Impact on Plantation Forest Landscape Visual Sensitivity
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Huijuan Yang, Yongning Li, Zhidong Zhang, Zhongqi Xu, and Xuanrui Huang
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plantation forest landscape ,visual sensitivity ,MCE ,GIS ,AHP ,seasonality ,Plant ecology ,QK900-989 - Abstract
Visual sensitivity assessments identify the location of the high-sensitivity areas in terms of visual change. Studying the visual sensitivity of plantation forest landscapes and their seasonal changes can help resolve increasingly frequent conflicts between tourism and forest management activities, in the context of the multi-functional management of plantation forests. In this study, we used the geographic information system (GIS) and multi-criteria evaluation (MCE) methods combined with the analytic hierarchy process (AHP) to perform a visual sensitivity evaluation. Nine map-based criteria were selected, and the visual sensitivity of summer and autumn values were calculated, using data from sources including inventory data for forest management planning and design, digital elevation model (DEM), and aerial photographs. Vegetation uniformity (VU) and color diversity (CD) indices were constructed using three patch-level-based landscape indices, including area (AREA), fractal dimension index (FRAC), and proximity (PROX), to visualize the summer and autumn vegetation characteristics of a plantation forest landscape. We conducted a case study on the Saihanba Mechanical Forest Plantation, China’s largest forest plantation. The results were evaluated by experts, confirming the method to be reliable. This study provides an accurate, objective, and visualized evaluation method for the visual sensitivity of plantations for forest management units at the landscape scale. In analyzing the visual sensitivity of plantation forest landscapes, appropriate criteria, e.g., uniformity or diversity should be selected based on forest vegetation characteristics. When identifying high-sensitivity regions, it is necessary to simultaneously analyze areas with high visual sensitivity in different seasons and then superimpose the results.
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- 2019
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67. Metabolic Modulation of Visual Sensitivity
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Barlow, Robert B., Farell, Bart, Khan, Mukhtar, LaVail, Matthew M., editor, Hollyfield, Joe G., editor, and Anderson, Robert E., editor
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- 2003
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68. Increased Visual Sensitivity and Occipital Activity in Patients With Hemianopia Following Vision Rehabilitation
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Kristin Jünemann, Arash Sahraie, Sara Ajina, and Holly Bridge
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medicine.medical_specialty ,genetic structures ,medicine.medical_treatment ,Development/Plasticity/Repair ,Vision Disorders ,Optic chiasm ,Audiology ,Affect (psychology) ,rehabilitation ,Blindness, Cortical ,Quality of life ,perimetry ,Medicine ,Humans ,Vision rehabilitation ,cortical blindness ,Research Articles ,Visual Cortex ,hemianopia ,Rehabilitation ,business.industry ,General Neuroscience ,Visual sensitivity ,eye diseases ,Visual field ,V5/hMT ,medicine.anatomical_structure ,functional MRI ,Visual Fields ,business ,Occipital lobe - Abstract
Hemianopia, loss of vision in half of the visual field, results from damage to the visual pathway posterior to the optic chiasm. Despite negative effects on quality of life, few rehabilitation options are currently available. Recently, several long-term training programs have been developed that show visual improvement within the blind field, although little is known of the underlying neural changes. Here, we have investigated functional and structural changes in the brain associated with visual rehabilitation. Seven human participants with occipital lobe damage enrolled in a visual training program to distinguish which of two intervals contained a drifting Gabor patch presented within the blind field. Participants performed ∼25 min of training each day for 3–6 months and undertook psychophysical tests and a magnetic resonance imaging scan before and after training. A control group undertook psychophysical tests before and after an equivalent period without training. Participants who were not at ceiling on baseline tests showed on average 9.6% improvement in Gabor detection, 8.3% in detection of moving dots, and 9.9% improvement in direction discrimination after training. Importantly, psychophysical improvement only correlated with improvement in Humphrey perimetry in the trained region of the visual field. Whole-brain analysis showed an increased neural response to moving stimuli in the blind visual field in motion area V5/hMT. Using a region-of-interest approach, training had a significant effect on the blood oxygenation level-dependent signal compared with baseline. Moreover, baseline V5/hMT activity was correlated to the amount of improvement in visual sensitivity using psychophysical and perimetry tests. This study, identifying a critical role for V5/hMT in boosting visual function, may allow us to determine which patients may benefit most from training and design adjunct interventions to increase training effects. SIGNIFICANCE STATEMENT Homonymous visual field loss is a common consequence of brain injury and is estimated to affect more than 230,000 people in the United Kingdom. Despite its high prevalence and well-described impact on quality of life, treatments to improve visual sensitivity remain experimental, and deficits are considered permanent after 6 months. Our study shows that behavioral changes following vision rehabilitation are associated with enhanced visually-evoked occipital activity to stimuli in the blind visual field. Unlike previous behavioral studies, we observe clinical changes that are specific to the trained region of vision. This lends significant weight to such training paradigms and offers a mechanism by which visual function can be improved despite damage to the primary visual pathway.
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- 2021
69. Comparison of central visual sensitivity between monocular and binocular testing in advanced glaucoma patients using imo perimetry
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Tomoyuki Kumagai, Yuji Yoshikawa, Hirokazu Ishii, Junji Kanno, Kei Shinoda, Itaru Kimura, Sho Ishikawa, Takuhei Shoji, Izumi Mine, and Akane Saito
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Male ,Retinal Ganglion Cells ,Visual acuity ,genetic structures ,Visual Acuity ,Glaucoma ,0302 clinical medicine ,Nerve Fibers ,Medicine ,Aged, 80 and over ,Vision, Binocular ,Clinical Science ,Middle Aged ,Visual sensitivity ,Sensory Systems ,Visual field ,Female ,medicine.symptom ,Glaucoma, Open-Angle ,medicine.medical_specialty ,field of vision ,Vision Disorders ,Sensitivity and Specificity ,Perimeter ,03 medical and health sciences ,Cellular and Molecular Neuroscience ,Predictive Value of Tests ,Vision, Monocular ,Ophthalmology ,Humans ,In patient ,False Positive Reactions ,Intraocular Pressure ,Aged ,Monocular ,business.industry ,medicine.disease ,eye diseases ,Absolute deviation ,glaucoma ,Cross-Sectional Studies ,physiology ,030221 ophthalmology & optometry ,Quality of Life ,Visual Field Tests ,sense organs ,Visual Fields ,business ,030217 neurology & neurosurgery - Abstract
Background/AimThis study aimed to compare central visual sensitivity under monocular and binocular conditions in patients with glaucoma using the new imo static perimetry.MethodsFifty-one consecutive eyes of 51 patients with open-angle glaucoma who were affected with at least one significant point in the central 10° were examined in this cross-sectional study. Monocular and binocular random single-eye tests were performed using the imo perimeter and the Humphrey field analyser (HFA) 24-2 and 10-2 tests. The eyes were assigned to ‘better’ and ‘worse’ categories based on the visual acuity and central visual thresholding. Central visual sensitivity results obtained by monocular, binocular random single-eye tests and binocular simultaneous both eye test were compared.ResultsThe average mean deviation with the HFA 24-2 was −5.5 (–1.5, –14.6) dB (median, (IQR)) in the better eyes and −18.0 (–12.9, –23.8) dB in the worse eyes. The mean sensitivity in the central 4 points of the visual field (VF) of the worse eyes was lower when measured under the binocular eye condition than under the monocular condition. Conversely, this value of the better eyes was greater when measured under the binocular eye condition than under the monocular condition.ConclusionsThe central sensitivity of the better eyes was better and that of the worse eyes poorer with binocular testing than with monocular testing in patients with glaucoma. Although monocular VF testing is still the most straightforward means to monocularly monitor glaucoma at clinical settings, binocular testing, such as provided with imo perimetry, may be a useful clinical tool to predict the effect of VF impairments on a patient’s quality of visual life.
- Published
- 2020
70. Unilateral increased visual sensitivity in cluster headache: a cross-sectional study
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Roemer B Brandt, Victor M Cnossen, Patty GG Doesborg, Ilse Frederieke de Coo, Matthijs J L. Perenboom, Johannes A Carpay, Roy Meilof, Gisela Marie Terwindt, Michel D Ferrari, and Rolf Fronczek
- Subjects
photophobia ,primary headache disorder ,Cross-Sectional Studies ,visual sensitivity ,Migraine Disorders ,Surveys and Questionnaires ,Humans ,Pain ,Cluster Headache ,Neurology (clinical) ,General Medicine ,headache - Abstract
Background and Objectives Increased sensitivity to light and patterns is typically associated with migraine, but has also been anecdotally reported in cluster headache, leading to diagnostic confusion. We wanted to assess whether visual sensitivity is increased ictally and interictally in cluster headache. Methods We used the validated Leiden Visual Sensitivity Scale (L-VISS) questionnaire (range 0-36 points) to measure visual sensitivity in people with episodic or chronic cluster headache: (i) during attacks; (ii) in-between attacks; and in episodic cluster headache (iii) in-between bouts. The L-VISS scores were compared with the L-VISS scores obtained in a previous study in healthy controls and participants with migraine. Results Mean L-VISS scores were higher for: (i) ictal vs interictal cluster headache (episodic cluster headache: 11.9 ± 8.0 vs. 5.2 ± 5.5, chronic cluster headache: 13.7 ± 8.4 vs 5.6 ± 4.8; p Conclusion Cluster headache is associated with increased ictal and interictal visual sensitivity. In contrast to migraine, this is mostly unilateral and ipsilateral on the side of the ictal pain.
- Published
- 2022
71. [Untitled]
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photophobia ,primary headache disorder ,Cluster headache ,visual sensitivity ,headache - Abstract
Background and Objectives Increased sensitivity to light and patterns is typically associated with migraine, but has also been anecdotally reported in cluster headache, leading to diagnostic confusion. We wanted to assess whether visual sensitivity is increased ictally and interictally in cluster headache.Methods We used the validated Leiden Visual Sensitivity Scale (L-VISS) questionnaire (range 0-36 points) to measure visual sensitivity in people with episodic or chronic cluster headache: (i) during attacks; (ii) in-between attacks; and in episodic cluster headache (iii) in-between bouts. The L-VISS scores were compared with the L-VISS scores obtained in a previous study in healthy controls and participants with migraine.Results Mean L-VISS scores were higher for: (i) ictal vs interictal cluster headache (episodic cluster headache: 11.9 +/- 8.0 vs. 5.2 +/- 5.5, chronic cluster headache: 13.7 +/- 8.4 vs 5.6 +/- 4.8; p < 0.001); (ii) interictal cluster headache vs controls (5.3 +/- 5.2 vs 3.6 +/- 2.8, p < 0.001); (iii) interictal chronic cluster headache vs interictal ECH in bout (5.9 +/- 0.5 vs 3.8 +/- 0.5, p = 0.009), and (iv) interictal episodic cluster headache in bout vs episodic cluster headache out-of-bout (5.2 +/- 5.5 vs. 3.7 +/- 4.3, p < 0.001). Subjective visual hypersensitivity was reported by 110/121 (91%; 9 missing) participants with cluster headache and was mostly unilateral in 70/110 (64%) and ipsilateral to the ictal pain in 69/70 (99%) participants.Conclusion Cluster headache is associated with increased ictal and interictal visual sensitivity. In contrast to migraine, this is mostly unilateral and ipsilateral on the side of the ictal pain.
- Published
- 2022
72. Rod and frame test and posture under optokinetic stimulation used to explore two complementary aspects of the visual influence in postural control after stroke.
- Author
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Tasseel-Ponche, Sophie, Le Liepvre, Hélène, Colle, Florence, Andriantsifanetra, Cédric, Vidal, Pierre-Paul, Bonan, Isabelle Véronique, and Yelnik, Alain-Pierre
- Subjects
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STROKE , *ROD & frame Test , *MOVEMENT disorders , *MEDICAL rehabilitation , *POSTURE - Abstract
Background: Balance rehabilitation should consider individual comportments according to visual input (VI). Indeed, visual dependence (VD), defined as the predominance given to the VI whatever the circumstances, frequent after stroke it could disturb balance. Because the term VD is a bit restrictive and cannot be deduced from clinical tests, the term visual sensitivity (VS) is preferred here.Hypothesis: VI could have different influence depending on the task for a given individual.Methods: We retrospectively compared 2 VS tests routinely used: the rod and frame test (RFT) and optokinetic stimulation (OKS). In RFT, VS was defined by a misperception of the visual verticality induced by a tilted frame (VS RFT) and in OKS by tilted sitting posture induced by rotational OKS (VS OKS). We studied the relations between VS RFT and VS OKS.Results: We analysed data for 84 patients, mean age 55±10years, 45±30days after stroke. Scores for both tests were correlated with autonomy measured by the functional independence measure (r=-0.3, p=0.01 and r=-0.2, p=0.02). VS OKS score was also correlated with balance measured by the postural assessment scale for stroke (r=-0.3, p=0.03). VS RFT score was not correlated with VS OKS score (p=0.4, r=0.04).Discussion- Conclusion: A patient may display VS for one test without sensitivity for the other because these tests investigate different neural organisation - perception for RFT or action for OKS. Their relation to balance disorders should be further investigated to build individualized rehabilitation programs. [ABSTRACT FROM AUTHOR]- Published
- 2017
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73. Rapid and Parallel Adaptive Evolution of the Visual System of Neotropical Midas Cichlid Fishes.
- Author
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Torres-Dowdall, Juliáan, Pierotti, Michele E. R., Härer, Andreas, Karagic, Nidal, Woltering, Joost M., Henning, Frederico, Elmer, Kathryn R., and Meyer, Axel
- Abstract
Midas cichlid fish are a Central American species flock containing 13 described species that has been dated to only a few thousand years old, a historical timescale infrequently associated with speciation. Their radiation involved the colonization of several clear water crater lakes from two turbid great lakes. Therefore, Midas cichlids have been subjected to widely varying photic conditions during their radiation. Being a primary signal relay for information from the environment to the organism, the visual system is under continuing selective pressure and a prime organ system for accumulating adaptive changes during speciation, particularly in the case of dramatic shifts in photic conditions. Here, we characterize the full visual systemof Midas cichlids at organismal and genetic levels, to determine what types of adaptive changes evolved within the short time span of their radiation. We show that Midas cichlids have a diverse visual system with unexpectedly high intra- and interspecific variation in color vision sensitivity and lens transmittance. Midas cichlid populations in the clear crater lakes have convergently evolved visual sensitivities shifted toward shorter wavelengths compared with the ancestral populations fromthe turbid great lakes. This divergence in sensitivity is driven by changes in chromophore usage, differential opsin expression, opsin coexpression, and to a lesser degree by opsin coding sequence variation. The visual system of Midas cichlids has the evolutionary capacity to rapidly integrate multiple adaptations to changing light environments. Our data may indicate that, in early stages of divergence, changes in opsin regulation could precede changes in opsin coding sequence evolution. [ABSTRACT FROM AUTHOR]
- Published
- 2017
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74. Visual sensitivity for luminance and chromatic stimuli during the execution of smooth pursuit and saccadic eye movements.
- Author
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Braun, Doris I., Schütz, Alexander C., and Gegenfurtner, Karl R.
- Subjects
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CONTRAST sensitivity (Vision) , *SACCADIC eye movements , *LUMINANCE (Photometry) , *COLOR vision , *FREQUENCY discriminators , *EYE movements , *LIGHT , *VISUAL perception - Abstract
Visual sensitivity is dynamically modulated by eye movements. During saccadic eye movements, sensitivity is reduced selectively for low-spatial frequency luminance stimuli and largely unaffected for high-spatial frequency luminance and chromatic stimuli (Nature 371 (1994), 511-513). During smooth pursuit eye movements, sensitivity for low-spatial frequency luminance stimuli is moderately reduced while sensitivity for chromatic and high-spatial frequency luminance stimuli is even increased (Nature Neuroscience, 11 (2008), 1211-1216). Since these effects are at least partly of different polarity, we investigated the combined effects of saccades and smooth pursuit on visual sensitivity. For the time course of chromatic sensitivity, we found that detection rates increased slightly around pursuit onset. During saccades to static and moving targets, detection rates dropped briefly before the saccade and reached a minimum at saccade onset. This reduction of chromatic sensitivity was present whenever a saccade was executed and it was not modified by subsequent pursuit. We also measured contrast sensitivity for flashed high- and low-spatial frequency luminance and chromatic stimuli during saccades and pursuit. During saccades, the reduction of contrast sensitivity was strongest for low-spatial frequency luminance stimuli (about 90%). However, a significant reduction was also present for chromatic stimuli (about 58%). Chromatic sensitivity was increased during smooth pursuit (about 12%). These results suggest that the modulation of visual sensitivity during saccades and smooth pursuit is more complex than previously assumed. [ABSTRACT FROM AUTHOR]
- Published
- 2017
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75. Processing of single-photon responses in the mammalian On and Off retinal pathways at the sensitivity limit of vision.
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Daisuke Takeshita, Smeds, Lina, and Ala-Laurila, Petri
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- *
PHOTONS , *MAMMAL behavior , *RETINA physiology , *GANGLIA , *PHOTOBIOLOGY - Abstract
Visually guided behaviour at its sensitivity limit relies on single-photon responses originating in a small number of rod photoreceptors. For decades, researchers have debated the neural mechanisms and noise sources that underlie this striking sensitivity. To address this question, we need to understand the constraints arising from the retinal output signals provided by distinct retinal ganglion cell types. It has recently been shown in the primate retina that On and Off parasol ganglion cells, the cell types likely to underlie light detection at the absolute visual threshold, differ fundamentally not only in response polarity, but also in the way they handle single-photon responses originating in rods. The On pathway provides the brain with a thresholded, low-noise readout and the Off pathway with a noisy, linear readout. We outline the mechanistic basis of these different coding strategies and analyse their implications for detecting the weakest light signals. We show that high-fidelity, nonlinear signal processing in the On pathway comes with costs: more single-photon responses are lost and their propagation is delayed compared with the Off pathway. On the other hand, the responses of On ganglion cells allow better intensity discrimination compared with the Off ganglion cell responses near visual threshold. [ABSTRACT FROM AUTHOR]
- Published
- 2017
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76. Coping with copepods: do right whales (Eubalaena glacialis) forage visually in dark waters?
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Cronin, Thomas W., Fasick, Jeffry I., Schweikert, Lorian E., Johnsen, Sönke, Kezmoh, Lorren J., and Baumgartner, Mark F.
- Subjects
- *
COPEPODA , *NORTHERN right whale , *PLANKTON , *SEAWATER , *FORAGING behavior - Abstract
North Atlantic right whales (Eubalaena glacialis) feed during the spring and early summer in marine waters off the northeast coast of North America. Their food primarily consists of planktonic copepods, Calanus finmarchicus, which they consume in large numbers by ram filter feeding. The coastal waters where these whales forage are turbid, but they successfully locate copepod swarms during the day at depths exceeding 100 m, where light is very dim and copepod patches may be difficult to see. Using models of E. glacialis visual sensitivity together with measurements of light in waters near Cape Cod where they feed and of light attenuation by living copepods in seawater, we evaluated the potential for visual foraging by these whales. Our results suggest that vision may be useful for finding copepod patches, particularly if E. glacialis searches overhead for silhouetted masses or layers of copepods. This should permit the whales to locate C. finmarchicus visually throughout most daylight hours at depths throughout their foraging range. Looking laterally, the whales might also be able to see copepod patches at short range near the surface. [ABSTRACT FROM AUTHOR]
- Published
- 2017
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77. Research on watermarking payload under the condition of keeping JPEG image transparency.
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Mao, Jia-Fa, Sheng, Wei-Guo, Hu, Ya-Hong, Xiao, Gang, Qu, Zhi-Guo, Niu, Xin-Xin, and Zhu, Li-Nan
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DIGITAL image watermarking ,JPEG (Image coding standard) ,EMBEDDED computer systems ,DIGITAL images ,MATHEMATICAL models - Abstract
This work focuses on the problem of maximum watermarking payload under the condition of keeping image transparency. The maximum watermarking payload of JPEG images is influenced by internal factors such as the size, complexity and visual sensitivity of images, as well as external factors including embedding operators, carrier frequency bands and embedding intensity, etc. Through the construction of payload mathematical model, theoretic analysis and experimental derivation we propose an estimation method of maximum watermarking payload based on the DCT coefficients. The feasibility and efficiency of the proposed method has been demonstrated in our experiments by adopting two embedding operators and three carrier frequency bands. Our results show, in comparison with previously related work, the proposed method can be more practical. [ABSTRACT FROM AUTHOR]
- Published
- 2017
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78. Are Differences Between Men and Women in Rotated Pattern Recognition Due to the Use of Different Cognitive Strategies?
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Catherine Brandner and Cédric Devaud
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sex differences ,visuo-spatial cognition ,discrimination ,mental rotation ,visual sensitivity ,clockwise and counterclockwise rotations ,Psychology ,BF1-990 - Abstract
A recursive hypothesis suggests that gender differences in spatial abilities, including mental rotation tasks, are the result of differences in the strategies that men and women use to process information. To address this issue, we systematically explored men and women’s performance for rotated patterns by assessing recognition, confidence rating and response time, thought to be fundamental to spatial processing, with classical methods, and with signal detection theory (SDT) parameters (d-prime and c-bias). Among our findings, we highlight d-prime as the most robust parameter to assess gender differences and predict group membership. Furthermore, we conclude that better performance by men is due to their strategy of transforming a mental rotation task into a simpler task comparing the alignment of test stimuli to the surrounding experimental environment.
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- 2013
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79. Variability of chromatic visual sensitivity: discrimination according to daily shifts
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Maria Thalita Cardoso Rezende, Bruna Gabrielli Damascena de Figueiredo, Thiago Augusto de Souza Bonifácio, Natanael Antonio dos Santos, and Michael Jackson Oliveira de Andrade
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medicine.medical_specialty ,Physiology ,Color vision ,0402 animal and dairy science ,Healthy subjects ,04 agricultural and veterinary sciences ,Audiology ,040201 dairy & animal science ,Visual sensitivity ,03 medical and health sciences ,0302 clinical medicine ,Variation (linguistics) ,Physiology (medical) ,medicine ,Chromatic scale ,Psychology ,030217 neurology & neurosurgery ,Ecology, Evolution, Behavior and Systematics - Abstract
This study aimed to verify the daily variation in the chromatic visual sensitivity of healthy subjects. The study included 35 male adults, aged between 20 and 40 years old (M = 24.97; SD = 4.9). Th...
- Published
- 2020
80. UV sensitive vision in cardinals and tanagers is ubiquitous
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Pablo D Lavinia, Belén Casalía, Pablo L. Tubaro, Ana S. Barreira, and Elisabet Vilacoba
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Physics ,Optics ,genetic structures ,business.industry ,Colour Vision ,Animal Science and Zoology ,Photopigment ,sense organs ,business ,Visual sensitivity ,Cone (formal languages) ,Ecology, Evolution, Behavior and Systematics ,Nature and Landscape Conservation - Abstract
Short wavelength visual sensitivity in birds is determined mostly by the type of photopigment present in the short-wavelength sensitive cone 1 (SWS1) which varies between clades and takes two main forms: the violet sensitive type (VS) and ultraviolet sensitive type (UVS). The common ancestor of passerines is thought to have been UVS, but there were at least 8 transitions between both types of visual sensitivity, even within species of the same family (Maluridae). The type of visual system a species has is a key parameter of avian visual models employed to describe chromatic visual perception and assess if colour differences are discernible by birds. Cardinalidae and Thraupidae together include more than 400 very diverse species that were model organisms in many bird colouration studies. However, visual sensitivity has been characterised for only one species of each of these families so far. Here, we obtained partial genetic sequences of the SWS1 opsin gene that determines the spectral sensitivity of the photopigment for a phylogenetically broad species sample of these families. All cardinals and tanagers studied here have SWS1 sequences corresponding with UVS sensitivity, suggesting that this character is conserved in these bird families despite their highly diverse range of plumage colours and habitat types.
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- 2020
81. Obstacle avoidance in bumblebees is robust to changes in light intensity
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Emily Baird
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030110 physiology ,0301 basic medicine ,Forage (honey bee) ,Light ,Vision ,Computer science ,Short Communication ,Dusk ,Experimental and Cognitive Psychology ,Motion ,03 medical and health sciences ,0302 clinical medicine ,Obstacle avoidance ,Animals ,Computer vision ,Bumblebee ,Ecology, Evolution, Behavior and Systematics ,Light intensity ,business.industry ,Bees ,Visual sensitivity ,Visual field ,Flight ,Flight, Animal ,Obstacle ,Artificial intelligence ,Visual Fields ,Fast motion ,business ,Insect ,030217 neurology & neurosurgery - Abstract
Flying safely and avoiding obstacles in low light is crucial for the bumblebees that forage around dawn and dusk. Previous work has shown that bumblebees overcome the limitations of their visual system—typically adapted for bright sunlight—by increasing the time over which they sample photons. While this improves visual sensitivity, it decreases their capacity to resolve fast motion. This study investigates what effect this has on obstacle avoidance in flight, a task that requires the bees to reliably detect obstacles in the frontal visual field and to make a timely diversion to their flight path. In both bright and dim light, bumblebees avoided the 5 cm diameter obstacle at a consistent distance (22 cm) although in dim light they approached it more slowly from a distance of at least at least 80 cm. This suggests that bumblebees have an effective strategy for avoiding obstacles in all light conditions under which they are naturally active, and it is hypothesised that this is based on a time-to-contact prediction. Electronic supplementary material The online version of this article (10.1007/s10071-020-01421-z) contains supplementary material, which is available to authorized users.
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- 2020
82. Perceptual saccadic suppression starts in the retina
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Thomas Münch, Saad Idrees, Felix Franke, Ziad M. Hafed, and Matthias Baumann
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Male ,Visual perception ,genetic structures ,Photic Stimulation ,Swine ,Computer science ,General Physics and Astronomy ,Visual processing ,Mice ,chemistry.chemical_compound ,0302 clinical medicine ,lcsh:Science ,media_common ,Neurons ,0303 health sciences ,Multidisciplinary ,Visual sensitivity ,medicine.anatomical_structure ,Visual Perception ,Female ,Adult ,media_common.quotation_subject ,Science ,Image processing ,Fixation, Ocular ,General Biochemistry, Genetics and Molecular Biology ,Article ,Retina ,Young Adult ,03 medical and health sciences ,Perception ,Reaction Time ,Saccades ,medicine ,Animals ,Humans ,Vision, Ocular ,030304 developmental biology ,Eye movement ,Retinal ,General Chemistry ,Saccadic masking ,eye diseases ,Mice, Inbred C57BL ,chemistry ,Fixation (visual) ,lcsh:Q ,sense organs ,Visual Fields ,Neuroscience ,030217 neurology & neurosurgery - Abstract
Visual sensitivity, probed through perceptual detectability of very brief visual stimuli, is strongly impaired around the time of rapid eye movements. This robust perceptual phenomenon, called saccadic suppression, is frequently attributed to active suppressive signals that are directly derived from eye movement commands. Here we show instead that visual-only mechanisms, activated by saccade-induced image shifts, can account for all perceptual properties of saccadic suppression that we have investigated. Such mechanisms start at, but are not necessarily exclusive to, the very first stage of visual processing in the brain, the retina. Critically, neural suppression originating in the retina outlasts perceptual suppression around the time of saccades, suggesting that extra-retinal movement-related signals, rather than causing suppression, may instead act to shorten it. Our results demonstrate a far-reaching contribution of visual processing mechanisms to perceptual saccadic suppression, starting in the retina, without the need to invoke explicit motor-based suppression commands., Nature Communications, 11 (1), ISSN:2041-1723
- Published
- 2020
83. A perceptual rate control algorithm based on luminance adaptation for HEVC encoders
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Dong-Gyu Sim and Woong Lim
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Pixel ,Computer science ,Quantization (signal processing) ,media_common.quotation_subject ,Rate control ,020206 networking & telecommunications ,02 engineering and technology ,Visual sensitivity ,Luminance ,Perception ,Signal Processing ,0202 electrical engineering, electronic engineering, information engineering ,020201 artificial intelligence & image processing ,Electrical and Electronic Engineering ,Subjective quality ,Algorithm ,Encoder ,media_common - Abstract
This paper proposes a rate control algorithm by selecting a proper quantization parameter (QP) based on perceptual luminance adaptation in a single-loop encoding fashion. In this paper, the proposed algorithm uses the visual characteristics of humans to adaptively decide the number of bits available for a pixel. Then, a base QP is selected based on the proposed R–λ model. The proposed rate control determines the range of QP based on the base QP and calculates the maximum and minimum bpps within that range. The optimal bpp is obtained from the bpp range by considering the visual characteristics of the human being, and the QP value is determined by the optical bpp through the proposed R–λ model. In the proposed rate control algorithm, the QP value is selected based on the R–λ model by considering the perceptual luminance adaptation model at the CTU level. The number of target bits is decided to decide the QP, subject to visual sensitivity based on JND thresholds. With the use of the proposed rate control algorithm, bits for non-noticeable regions can be saved, and the remaining bits can be consumed for perceptually noticeable regions to enhance the overall subjective quality with the similar amount of total bits. The proposed method shows lower average variances of bits and PSNR fluctuations. Also, the proposed method achieves an approximately 0.19 higher MOS value on average under DSCQS test, compared with the conventional R–λ model-based rate control algorithm.
- Published
- 2020
84. Histología y morfometría del ojo del pez dulceacuícola Paracheirodon axelrodi (Characiformes: Characidae)
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Mario O Tovar, Martha J Obando, Edwin Gómez, María L Caldas, and Hernán Hurtado
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histología ,sensibilidad visual ,morfometría ,ecología visual ,teleósteos ,histology ,visual sensitivity ,morphometry ,visual ecology ,teleosts ,Biology (General) ,QH301-705.5 - Abstract
El pez dulceacuícola P. axelrodi es de gran importancia comercial en la Orinoquía Colombiana y a nivel mundial, pero carece de estudios acerca de su visión. Se utilizaron diez individuos, con longitud total promedio de 2.7 cm (SD= 0.2, n= 20). Se realizaron cortes a 8 μm y se tiρeron con H-E. El tamaρo relativo del ojo es 9.8% (SD= 1.1, n= 20); el cristalino tiene un tamaρo relativo de 64.3% (SD= 4.9, n=20). Una esclerótica con tejido cartilaginoso. La retina está constituida por ocho capas y dos membranas, hay areae centrales en la zona posterior, por lo tanto tiene mayor espesor que la zona lateral. El espesor promedio de las estructuras es: retina lateral: 144.5 μm (SD= 5.4, n= 20), retina temporal: 210.4 μm (SD= 14.8, n= 20); cristalino (esfιrico): dorso-ventral 759.6 μm (SD= 31.7, n= 20) y antero- posterior 763.4 μm (SD= 30.7, n= 20) y cσrnea: 27.6 μm (SD= 4.3, n= 20). El tamaρo relativo del ojo, relacionado con la presencia de areae centrales y una córnea delgada, muestra las necesidades visuales del neón cardenal (cazador) para adaptarse al hábitat, lo que hace necesario tener un sistema visual desarrollado que le permita tener mejor sensibilidad y resolución visual.Histology and morphometry of the eye in the freshwater Paracheirodon axelrodi (Characiformes: Characidae). The visual system of Teleost fishes has a wide range of adaptations. The eye has suffered modifications, mainly towards better sensitivity and visual resolution according to specific environmental conditions. In that way, this organ is so important for survival. In spite of being the most commercialized Orinoquía species, and one of the most important ornamental fish worldwide, there are almost no studies on the communication systems of P. axelrodi (including vision). We studied the eye in ten individuals of P. axelrodi, with a mean total length of 2.7 cm (SD= 0.2, n= 20). We measured eye relative size (TRO) after sacrifice. Heads were processed for hematoxylin-eosin, and 8 μm thick sections were obtained. Images were digitalized for histological identification and morphometrics. The relation between TRO and body length was 9.8% (SD= 1.1, n= 20); lens was spherical with a relative size of 64.3% (SD= 4.9, n= 20). Rete mirabilis choroid was composed mainly by capillaries, while sclera was composed of cartilaginous tissue. Retina with eight layers and two membranes. An areae centrales was observed in the posterior retina. Iris covered by a simple cubic epithelium. Cornea of endothelial tissue with two membranes. Pupil almost circular, with a naso-caudal elongation. Measures of retina thickness were as follows: lateral retina 144.5 μm (SD= 5.4, n= 20), temporal retina 210.4 μm (SD= 14.8, n= 20). Lens measurements were: dorso- ventral 759.6 μm (SD= 31.7, n= 20), antero-posterior 763.4 μm (SD= 30.7, n= 20). Cornea thickness was 27.6 μm (SD= 4.3, n= 20); iris thickness was 18.9 μm (SD= 1.9, n= 20); rete mirabilis choroid 22.2 μm (SD= 3.2, n= 20) and sclera: 15.9 μm (SD= 1.2, n= 20). This species has a typical Teleost eye conformation. The retina was thicker in the posterior area, probably related to the presence of neuron groups. This modification allows for a better sharpness and visual resolution. The TRO, areae centrales in the retina, and thin cornea, suggests the need of a well developed visual system resulting from a predatory diet. Rev. Biol. Trop. 57 (4): 1107-1118. Epub 2009 December 01.
- Published
- 2009
85. On-Bipolar Cells, Visual Sensitivity and the b-Wave
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Falk, Gertrude, Shiells, Richard A., Robbins, Jon G., editor, Djamgoz, Mustafa B. A., editor, and Taylor, Anthony, editor
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- 1995
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86. Visual space curves before eye movements
- Author
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Ifedayo-EmmanuEL Adeyefa-Olasupo
- Subjects
Visual processing ,business.industry ,Computer science ,Visual space ,Eye movement ,Computer vision ,Artificial intelligence ,Percept ,business ,Visual sensitivity ,Gaze - Abstract
In most experiments within the field of cognitive and systems neuroscience, fixation is often required prior to the onset of an experimental trial. However, the term “fixation” is rather misleading since our eyes are constantly moving. One type of transient miniature movement ubiquitously observed during fixation is commonly referred to as fixational eye movements or microsaccades. Perimicrosaccadic compression of visual space — the ability of retinotopic cells to transiently exhibit predictive spatiotemporal retinotopic compressive shifts toward the target of an impending microsaccade — is known to dramatically alter visual perception. However, whether perimicrosaccadic compressive shifts can become spatially asymmetric, that is, continuously directed toward a specific foveal region over another (e.g., an upper over a lower region in the fovea) and for what purpose, remains poorly understood. Assuming that these transient shifts are indeed asymmetric under certain conditions, the perceptual and oculomotor consequences such asymmetricity might accompany across visual space is poorly understood. Equally unaccounted for is a mechanistic account of the neural computation and architecture that could support these transient asymmetric shifts while the visual system actively maintains retinotopic organization. Here, we systematically measured visual sensitivity in human subjects to faint probes presented during fixation and around the time of saccadic eye movement at geometrically symmetric retinotopic locations in the foveal, parafoveal, and peripheral regions of visual space. Remarkably, we observed transient local asymmetric visual sensitivity differences between these symmetric retinotopic locations where none should be observed. Equally surprising, we observed the trajectories of saccadic eye movements, which are expected to travel along a linear path, routinely deviate along a curved path toward orthogonal eccentric locations. To provide a mechanistic account of the neural computation and architecture that may explain our results, we proposed a novel neurobiologically inspired phenomenological force field model in which underlying attentional and oculomotor signals are modulated by transient eccentric error signals that manifest as temporally overlapping predictive forces and impinge on the retinotopic visual cortex. These forces, which transiently bias putative population sensitivity toward an orthogonal retinotopic foveal region and, around the time of a saccadic eye movement, along an axis orthogonal to the saccade direction toward a mislocalized peripheral region, succinctly capture the essence of our empirical observations.
- Published
- 2021
87. Ultraviolet Visual Sensitivity in the Larvae of Two Species of Marine Atherinid Fishes
- Author
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William N. McFarland, Florence A. McAlary, and Ellis R. Loew
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Larva ,medicine ,Zoology ,Biology ,medicine.disease_cause ,Visual sensitivity ,Ultraviolet - Published
- 2021
88. Visual Cortex Engagement in Retinitis Pigmentosa
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Giambattista Bonanno, Tiziana Bonifacino, Laura Baroncelli, Lucia Galli, Alessandro Sale, Gianluca Pietra, and Davide Talamonti
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Male ,genetic structures ,QH301-705.5 ,Degeneration (medical) ,Biology ,Article ,Catalysis ,Inorganic Chemistry ,Mice ,retinitis pigmentosa ,Retinitis pigmentosa ,medicine ,Animals ,Physical and Theoretical Chemistry ,visual cortex ,Biology (General) ,Molecular Biology ,Inhibition ,Plasticity ,Rd10 mouse model ,Visual cortex ,QD1-999 ,Spectroscopy ,Neurotransmitter Agents ,Cortical circuits ,Organic Chemistry ,General Medicine ,medicine.disease ,rd10 mouse model ,Visual sensitivity ,eye diseases ,inhibition ,Computer Science Applications ,Mice, Inbred C57BL ,Functional integrity ,Chemistry ,medicine.anatomical_structure ,Retinal structure ,plasticity ,Intracortical inhibition ,Female ,Neuroscience ,Photoreceptor Cells, Vertebrate ,Synaptosomes - Abstract
Retinitis pigmentosa (RP) is a family of inherited disorders caused by the progressive degeneration of retinal photoreceptors. There is no cure for RP, but recent research advances have provided promising results from many clinical trials. All these therapeutic strategies are focused on preserving existing photoreceptors or substituting light-responsive elements. Vision recovery, however, strongly relies on the anatomical and functional integrity of the visual system beyond photoreceptors. Although the retinal structure and optic pathway are substantially preserved at least in early stages of RP, studies describing the visual cortex status are missing. Using a well-established mouse model of RP, we analyzed the response of visual cortical circuits to the progressive degeneration of photoreceptors. We demonstrated that the visual cortex goes through a transient and previously undescribed alteration in the local excitation/inhibition balance, with a net shift towards increased intracortical inhibition leading to improved filtering and decoding of corrupted visual inputs. These results suggest a compensatory action of the visual cortex that increases the range of residual visual sensitivity in RP.
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- 2021
89. Beauty and the Beholder: The Role of Visual Sensitivity in Visual Preference
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Branka eSpehar, Solomn eWong, Sarah evan de Klundert, Jessie eLui, Colin Walter Giles Clifford, and Richard eTaylor
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Fractals ,aesthetics ,visual preference ,contrast sensitivity function ,Visual Sensitivity ,1/f amplitude spectrum ,Neurosciences. Biological psychiatry. Neuropsychiatry ,RC321-571 - Abstract
For centuries, the essence of aesthetic experience has remained one of the most intriguing mysteries for philosophers, artists, art historians and scientists alike. Recently, views emphasizing the link between aesthetics, perception and brain function have become increasingly prevalent (Zeki, 1999; 2002; 2013; Ishizu & Zeki, 2013; Ramachandran & Hirstein, 1999; Livingstone, 2002). The link between art and the fractal structure of natural images has also been highlighted (Spehar, Newell, Clifford & Taylor, 2003; Graham and Field, 2007; Graham & Redies, 2010). Motivated by these claims and our previous findings that humans display a consistent preference across various fractal images, we explore here the possibility that observers' preference for visual patterns might be related to their sensitivity for such patterns. We measure sensitivity to simple visual patterns (sine-wave gratings varying in spatial frequency and random textures with varying fractal exponent) and find that they are highly correlated with visual preferences exhibited by the same observers. Although we do not attempt to offer a comprehensive neural model of aesthetic experience, we demonstrate a strong relationship between visual sensitivity and preference for simple visual patterns. Broadly speaking, our results support assertions that there is a close relationship between aesthetic experience and the sensory coding of natural stimuli.
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- 2015
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90. Improved visual information fidelity based on sensitivity characteristics of digital images.
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Kuo, Tien-Ying, Su, Po-Chyi, and Tsai, Cheng-Mou
- Subjects
- *
IMAGE processing , *DIGITAL images , *TRANSCODING , *COMPUTATIONAL complexity , *IMAGE quality analysis , *GABOR filters , *WAVELET transforms - Abstract
Digital images may lose certain information during transmission or transcoding processes. Since the lost information can influence the visual quality perceived by the human eyes, several quality assessment metrics have been proposed. The structural similarity index (SSIM) and visual information fidelity (VIF) are two of the most common methods that take characteristics of the human perceptual system into account. Although many improved metrics based on SSIM have been developed, the methods related to VIF, which outperforms SSIM-based approaches in certain image databases, have rarely been discussed. This research aims at improving VIF to increase the effectiveness and reduce its computational complexity. The enhanced VIF employs the Haar wavelet transform, log-Gabor filter, and spectral residual approach to emphasize the visual sensitivity in image quality assessment. The experimental results demonstrate the superior performance of the proposed method, when compared to various popular or latest assessment indices. [ABSTRACT FROM AUTHOR]
- Published
- 2016
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91. Interictal photosensitivity associates with altered brain structure in patients with episodic migraine.
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Chong, Catherine D., Starling, Amaal J., and Schwedt, Todd J.
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MIGRAINE , *PHOTOSENSITIZATION , *BRAIN anatomy , *PHOBIAS , *VISUAL cortex , *PARIETAL lobe , *MAGNETIC resonance imaging of the brain , *BRAIN , *DIAGNOSTIC imaging , *MAGNETIC resonance imaging , *COMPUTERS in medicine , *QUESTIONNAIRES , *VISION disorders - Abstract
Background: Migraine attacks manifest with hypersensitivities to light, sound, touch and odor. Some people with migraine have photosensitivity between migraine attacks, suggesting persistent alterations in the integrity of brain regions that process light. Although functional neuroimaging studies have shown visual stimulus induced "hyperactivation" of visual cortex regions in migraineurs between attacks, whether photosensitivity is associated with alterations in brain structure is unknown.Methods: Levels of photosensitivity were evaluated using the Photosensitivity Assessment Questionnaire in 48 interictal migraineurs and 48 healthy controls. Vertex-by-vertex measurements of cortical thickness were assessed in 28 people with episodic migraine who had interictal photosensitivity (mean age = 35.0 years, SD = 12.1) and 20 episodic migraine patients without symptoms of interictal photosensitivity (mean age = 36.0 years, SD = 11.4) using a general linear model design.Results: Migraineurs have greater levels of interictal photosensitivity relative to healthy controls. Relative to migraineurs without interictal photosensitivity, migraineurs with interictal photosensitivity have thicker cortex in several brain areas including the right lingual, isthmus cingulate and pericalcarine regions, and the left precentral, postcentral and supramarginal regions.Conclusion: Episodic migraineurs with interictal photosensitivity have greater cortical thickness in the right parietal-occipital and left fronto-parietal regions, suggesting that persistent light sensitivity is associated with underlying structural alterations. [ABSTRACT FROM AUTHOR]- Published
- 2016
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92. Effects of Nickel Oxide Nanoparticles on Visual Processes and Electro-Retinography Waves in the Bullfrog Eye.
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Wahid, Fazli, Khan, Romana, Khan, Taous, Ul-Islam, Mazhar, and You Young Kim
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ELECTRICAL properties of nickel oxides , *MAGNETIC properties of nanoparticles , *ELECTRORETINOGRAPHY , *VISUAL accommodation , *NANOMEDICINE - Abstract
The nickel oxide nanoparticles were synthesized and their effects were evaluated on the visual system of the vertebrate eye. The physico-chemical characterization of the prepared nanoparticles was carried out through transmission electron microscopy (TEM) and X-ray diffraction (XRD) measurements. Electroretinography (ERG) was used to evaluate the possible effects of the nickel oxide nanoparticles on the visual system. TEM and XRD measurements demonstrated that the size of nickel oxide nanoparticles was in the range of 4-10 nm. ERG results showed that nickel oxide nanoparticles markedly improve ERG b-wave amplitude during dark-adapted and in the presence of background light. Nickel oxide nanoparticles increased visual sensitivity by 0.4 log units of light intensity and also shortened the time required for rhodopsin regeneration. In conclusion, nickel oxide nanoparticles have positive effects on visual processes in vertebrate eye. [ABSTRACT FROM AUTHOR]
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- 2016
93. Temporal Visual Mechanisms May Mediate Compensation for Macular Pigment.
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Stringham, Nicole T. and Stringham, James M.
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Macular pigment (MP) is a pre-receptoral filter that is diet derived and deposited in relatively high optical density in the foveal region of the retina. Due to its yellow coloration, MP absorbs light of relatively short wavelengths, ranging from 400 nm to 520 nm. Despite the spectral and spatial nonuniformity imposed upon the sensory retina by MP, perception appears to be relatively uniform across the central visual field. MP therefore offers an opportunity to determine experimentally potential mechanisms responsible for mediating this uniformity. After assessing, in 14 subjects, MP’s effects on the temporal sensitivity of both the short-wavelength- and middle-/long-wavelength-sensitive visual pathways, it appears that the visual system compensates for absorption of short-wavelength light by MP by slowing the sampling rate of short-wavelength cones and by increasing the processing speed of middle-/long-wavelength-sensitive cones. This mechanism could work via temporal summation or a temporal neural code, whereby slower response dynamics lead to amplification of relatively weak signals. [ABSTRACT FROM AUTHOR]
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- 2015
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94. Significant correlations between focal photopic negative response and focal visual sensitivity and ganglion cell complex thickness in glaucomatous eyes
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Atsushi Tada, Tomoharu Nishimura, Mana Gonmori, Masahiko Ishizuka, Yuji Hara, Shigeki Machida, and Satoshi Ebihara
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Retinal Ganglion Cells ,medicine.medical_specialty ,genetic structures ,Open angle glaucoma ,Cell complex ,Glaucoma ,chemistry.chemical_compound ,Ophthalmology ,medicine ,Electroretinography ,Humans ,business.industry ,Retinal ,General Medicine ,medicine.disease ,Visual sensitivity ,eye diseases ,Ganglion ,medicine.anatomical_structure ,chemistry ,Visual Field Tests ,sense organs ,Visual Fields ,business ,Microperimetry ,Glaucoma, Open-Angle ,Tomography, Optical Coherence ,Photopic vision - Abstract
PURPOSE To determine whether there are significant correlations between the focal photopic negative response (PhNR), the focal visual sensitivity and the ganglion cell complex (GCC) thickness in glaucomatous eyes. STUDY DESIGN Single-center observational study. METHODS Fifty-two eyes of 52 patients (71.4 ± 9.42 years) with clinically diagnosed open angle glaucoma were studied. Thirty-six age-matched normal subjects served as controls. The focal PhNR of the focal macular electroretinograms (fmERGs) were elicited by a 15° circular, a superior semicircular or an inferior semicircular stimulus centered on the fovea. The thickness of the GCC was measured in the corresponding retinal areas in the spectral-domain optical coherence tomographic images. The visual sensitivities (dB) were measured by microperimetry at the retinal area where the fmERGs were elicited and were converted to liner values (1/Lambert). RESULTS The focal PhNR amplitudes were significantly correlated with the visual sensitivities of the full-circle (R = 0.532), the superior (R = 0.530) and inferior (R = 0.526) semicircular responses (P
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- 2021
95. Parallel shifts of visual sensitivity and body colouration in replicate populations of extremophile fish
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Thor Veen, Michael Tobler, Dylan R. Moxley, Lenin Arias-Rodriguez, Diana J. Rennison, and Gregory L. Owens
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0106 biological sciences ,genetic structures ,Zoology ,Biology ,010603 evolutionary biology ,01 natural sciences ,Poecilia mexicana ,Extremophiles ,03 medical and health sciences ,Genetics ,Animals ,Extremophile ,Hydrogen Sulfide ,14. Life underwater ,Selection, Genetic ,Ecology, Evolution, Behavior and Systematics ,030304 developmental biology ,Poecilia ,0303 health sciences ,Natural selection ,Replicate ,Adaptation, Physiological ,Visual sensitivity ,Mate choice ,Habitat ,Sexual selection ,sense organs ,Adaptation - Abstract
Visual sensitivity and body pigmentation are often shaped by both natural selection from the environment and sexual selection from mate choice. One way of quantifying the impact of the environment is by measuring how traits have changed after colonization of a novel habitat. To do this, we studied Poecilia mexicana populations that have repeatedly adapted to extreme sulphidic (H2S containing) environments. We measured visual sensitivity using opsin gene expression, as well as body pigmentation and water transmission for populations in four independent drainages. Both visual sensitivity and body pigmentation showed significant parallel shifts towards greater medium wavelength sensitivity and reflectance in sulphidic populations. The light spectrum was only subtly different between environments and overall, we found no significant correlations between the light environment and visual sensitivity or body pigmentation. Altogether we found that sulphidic habitats select for differences in visual sensitivity and pigmentation; our data suggest that this effect is unlikely to be driven purely by the water’s spectral properties and may instead be from other correlated ecological changes.
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- 2021
96. Development of the visual system
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Powers, Maureen K., Raymond, Pamela A., Douglas, Ron, editor, and Djamgoz, Mustafa, editor
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- 1990
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97. Cortical Hyper‐Excitability in Migraine in Response to Chromatic Patterns
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Pulkit Grover, Sarah M. Haigh, Alireza Chamanzar, and Marlene Behrmann
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Adult ,Male ,medicine.medical_specialty ,genetic structures ,Aura ,Migraine Disorders ,Audiology ,Young Adult ,03 medical and health sciences ,Neural activity ,0302 clinical medicine ,Humans ,Medicine ,030212 general & internal medicine ,Chromatic scale ,Chromaticity ,Hue ,Cerebral Cortex ,business.industry ,Electroencephalography ,Middle Aged ,medicine.disease ,Visual sensitivity ,Neurology ,Migraine ,Cortical Excitability ,Evoked Potentials, Visual ,Female ,Neurology (clinical) ,business ,Color Perception ,Photic Stimulation ,030217 neurology & neurosurgery - Abstract
Objective Individuals with migraine exhibit heightened sensitivity to visual input that continues beyond their migraine episodes. However, the contribution of color to visual sensitivity, and how it relates to neural activity, has largely been unexplored in these individuals. Background Previously, it has been shown that, in non-migraine individuals, patterns with greater chromaticity separation evoked greater cortical activity, regardless of hue, even when colors were isoluminant. Therefore, to investigate whether individuals with migraine experienced increased visual sensitivity, we compared the behavioral and neural responses to chromatic patterns of increasing separation in migraine and non-migraine individuals. Methods Seventeen individuals with migraine (12 with aura) and 18 headache-free controls viewed pairs of colored horizontal grating patterns that varied in chromaticity separation. Color pairs were either blue-green, red-green, or red-blue. Participants rated the discomfort of the gratings and electroencephalogram was recorded simultaneously. Results Both groups showed increased discomfort ratings and larger N1/N2 event-related potentials (ERPs) with greater chromaticity separation, which is consistent with increased cortical excitability. However, individuals with migraine rated gratings as being disproportionately uncomfortable and exhibited greater effects of chromaticity separation in ERP amplitude across occipital and parietal electrodes. Ratings of discomfort and ERPs were smaller in response to the blue-green color pairs than the red-green and red-blue gratings, but this was to an equivalent degree across the 2 groups. Conclusions Together, these findings indicate that greater chromaticity separation increases neural excitation, and that this effect is heightened in migraine, consistent with the theory that hyper-excitability of the visual system is a key signature of migraine.
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- 2019
98. Wavelength‐specific thresholds of artificially reared Japanese eelAnguilla japonicalarvae determined from negative‐phototactic behaviours
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Keishi Matsuda, Masaaki Kamoshida, and Yoshitsugu Masuda
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0106 biological sciences ,Light ,Aquaculture ,Aquatic Science ,010603 evolutionary biology ,01 natural sciences ,Japonica ,Optics ,Japan ,Anguillidae ,Phototaxis ,Animals ,Japanese eel ,Ecology, Evolution, Behavior and Systematics ,Larva ,biology ,business.industry ,010604 marine biology & hydrobiology ,Anguilla ,biology.organism_classification ,Visual sensitivity ,Wavelength ,Spectral sensitivity ,business - Abstract
We report wavelength-specific thresholds of leptocephali of Japanese eels Anguilla japonica determined from their negative-phototactic behaviour. Leptocephali are most sensitive to wavelengths 400-500 nm and at very short wavelengths. Their visual sensitivity decreases more sharply at wavelengths >500 nm than it does at wavelengths
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- 2019
99. Saccadic suppression measured by steady-state visual evoked potentials
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Matteo Valsecchi, Jing Chen, Karl R. Gegenfurtner, Chen J., Valsecchi M., and Gegenfurtner K.R.
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Adult ,Male ,Physics ,Steady state (electronics) ,Perception and action ,genetic structures ,Physiology ,General Neuroscience ,Spectrum analysi ,Saccadic eye movement ,Eye movement ,Neural Inhibition ,Visual evoked potentials ,Visual sensitivity ,Saccadic masking ,Reaction Time ,Saccades ,Visual Perception ,Evoked Potentials, Visual ,Humans ,Female ,Saccadic suppression ,Spectrum analysis ,Neuroscience ,SSVEP - Abstract
Visual sensitivity is severely impaired during the execution of saccadic eye movements. This phenomenon has been extensively characterized in human psychophysics and nonhuman primate single-neuron studies, but a physiological characterization in humans is less established. Here, we used a method based on steady-state visually evoked potential (SSVEP), an oscillatory brain response to periodic visual stimulation, to examine how saccades affect visual sensitivity. Observers made horizontal saccades back and forth, while horizontal black-and-white gratings flickered at 5–30 Hz in the background. We analyzed EEG epochs with a length of 0.3 s either centered at saccade onset (saccade epochs) or centered at fixations half a second before the saccade (fixation epochs). Compared with fixation epochs, saccade epochs showed a broadband power increase, which most likely resulted from saccade-related EEG activity. The execution of saccades, however, led to an average reduction of 57% in the SSVEP amplitude at the stimulation frequency. This result provides additional evidence for an active saccadic suppression in the early visual cortex in humans. Compared with previous functional MRI and EEG studies, an advantage of this approach lies in its capability to trace the temporal dynamics of neural activity throughout the time course of a saccade. In contrast to previous electrophysiological studies in nonhuman primates, we did not find any evidence for postsaccadic enhancement, even though simulation results show that our method would have been able to detect it. We conclude that SSVEP is a useful technique to investigate the neural correlates of visual perception during saccadic eye movements in humans. NEW & NOTEWORTHY We make fast ballistic saccadic eye movements a few times every second. At the time of saccades, visual sensitivity is severely impaired. The present study uses steady-state visually evoked potentials to reveal a neural correlate of the fine temporal dynamics of these modulations at the time of saccades in humans. We observed a strong reduction (57%) of visually driven neural activity associated with saccades but did not find any evidence for postsaccadic enhancement.
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- 2019
100. En Face Slab Images Visualize Nerve Fibers With Residual Visual Sensitivity in Significantly Thinned Macular Areas of Advanced Glaucomatous Eyes
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Sentaro Kusuhara, Mari Sakamoto, Makoto Nakamura, Takuji Kurimoto, Yuko Yamada-Nakanishi, Sotaro Mori, and Kaori Ueda
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Male ,Retinal Ganglion Cells ,structure-function correlation ,medicine.medical_specialty ,Materials science ,genetic structures ,Visual Acuity ,Glaucoma ,030209 endocrinology & metabolism ,Nerve fiber ,retinal nerve fiber bundle ,Slit Lamp Microscopy ,Retina ,03 medical and health sciences ,Nerve Fibers ,0302 clinical medicine ,Optical coherence tomography ,Macula Lutea ,Ophthalmology ,medicine ,Humans ,en face slab image ,Aged ,optical coherence tomography ,medicine.diagnostic_test ,Middle Aged ,medicine.disease ,Visual sensitivity ,eye diseases ,Ganglion ,medicine.anatomical_structure ,glaucoma ,030221 ophthalmology & optometry ,Slab ,Visual Field Tests ,Female ,sense organs ,Tomography ,Visual Fields ,Tomography, Optical Coherence - Abstract
Purpose: The present study aimed to assess the ability of en face slab images of maculae to detect residual nerve fiber bundles in eyes with advanced glaucoma. Methods: This study included 36 eyes with diffuse thinning of the ganglion cell and inner plexiform layers (GCL+IPL). Inclusion criterion was GCL+IPL thickness of
- Published
- 2019
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