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Visible light enters our body via the pupil. By changing its size, the pupil shapes visual input. Small apertures increase the resolution of high spatial frequencies, thus allowing discrimination of fine details. Large apertures, in contrast, provide a better signal-to-noise ratio, because more light can enter the eye. This should lead to better detection performance of peripheral stimuli. Experiment 1 shows that the effect can reliably be demonstrated even in a less controlled online setting. In Experiment 2, pupil size was measured in a laboratory using an eye tracker. The findings replicate findings showing that large pupils provide an advantage for peripheral detection of faint stimuli. Moreover, not only pupil size during information intake in the current trial n, but also its interaction with pupil size preceding information intake, i.e., in trial n-1, predicted performance. This suggests that in addition to absolute pupil size, the extent of pupillary change provides a mechanism to modulate perceptual functions. The results are discussed in terms of low-level sensory as well as higher-level arousal-driven changes in stimulus processing.

Con base en un trasfondo teórico sobre las concepciones modulares de la mente de Fodor (2001) y Pinker (2005), el objetivo del presente texto es analizar cualitativemente la solidez de la evidencia experimental de una muestra de artículos publicados entre 2002 y 2017 que apoyan la tesis de la penetrabilidad cognitiva en la percepción visual temprana. El estudio se justifica por las implicaciones que pueden tener los resultados de estas investigaciones para las diferentes concepciones sobre arquitectura mental en funciones perceptuales, procesamiento de la información intra e intermodular e isomorfismo entre arquitectura mental y cerebral. La metodología que se utilizó para realizar este estudio implicó establecimiento de la tesis y de los criterios de inclusión de los artículos a revisar, selección final de los artículos más representativos sobre las subáreas seleccionadas, análisis de la calidad metodológica y de los resultados de éstos, identificación de aportes específicos de cada estudio a la tesis planteada e interpretación y síntesis de los hallazgos. De 26 artículos revisados sobre el tema, se reportan y analizan 7, que se consideran representativos de 4 subáreas: penetrabilidad de expectativas, de percepción del color, de rasgos faciales y de reconocimiento de objetos. Se concluye que hay amplia y sólida evidencia convergente (perceptual y neurofisiológica) a favor de los fenómenos penetrativos en la visión temprana, lo cual apoyaría indirectamente la hipótesis de permeabilidad de los módulos mentales de Pinker. Se formulan recomendaciones sobre aspectos por investigar y variables a controlar en experimentos sobre este tema.

Neuromorphic devices that can emulate the bionic sensory and perceptual functions of neural systems have great applications in personal healthcare monitoring, neuro-prosthetics, and human–machine interfaces. In order to realize bionic sensing and perception, it’s crucial to prepare neuromorphic devices with the function of perceiving environment in real-time. Up to now, lots of efforts have been made in the incorporation of the bio-inspired sensing and neuromorphic engineering in the booming artificial intelligence industry. In this review, we first introduce neuromorphic devices based on diverse materials and mechanisms. Then we summarize the progress made in the emulation of biological sensing and perception systems. Finally, the challenges and opportunities in these fields are also discussed.

Axonal projection patterns are increasingly recognized as a defining feature for neuronal classification. How could such structural distinctions be linked to functions? In this issue of Neuron, Tang and Higley (2020) disambiguate behavior-level functions of two projection-defined subtypes of cortical projection neurons.

Previous studies indicate that temporal predictability can enhance timing and intensity perception, but it is not known whether it also enhances pitch perception, despite pitch being a fundamental perceptual attribute of sound. Here we investigate this in the context of rhythmic regularity, a form of predictable temporal structure common in sound streams, including music and speech. It is known that neural oscillations in low (delta: 1–3 Hz) and high (beta: 15–25 Hz) frequency bands entrain to rhythms in phase and power, respectively, but it is not clear why both low and high frequency bands entrain to external rhythms, and whether they and their coupling serve different perceptual functions. Participants discriminated near-threshold pitch deviations (targets) embedded in either rhythmic (regular/isochronous) or arrhythmic (irregular/non-isochronous) tone sequences. Psychophysically, we found superior pitch discrimination performance for target tones in rhythmic compared to arrhythmic sequences. Electroencephalography recordings from auditory cortex showed that delta phase, beta power modulation, and delta-beta coupling were all modulated by rhythmic regularity. Importantly, trial-by-trial neural-behavioural correlational analyses showed that, prior to a target, the depth of U-shaped beta power modulation predicted pitch discrimination sensitivity whereas cross-frequency coupling strength predicted reaction time. These novel findings suggest that delta phase might reflect rhythmic temporal expectation, beta power temporal attention, and delta-beta coupling auditory-motor communication. Together, low and high frequency auditory neural oscillations reflect different perceptual functions that work in concert for tracking rhythmic regularity and proactively facilitate pitch perception.

This study was conducted to compare cognitive and perceptual functions among patients with occipital lobe epilepsy, patients with migraine, and healthy individuals, in relation to the moderating roles of gender and educational level. Participants included 93 individuals from Mashhad City, Khorasan-e-Razavi province, Iran. A demographic questionnaire and Bender–Gestalt II (BGT-II; Brannigan & Decker, 2003) were used for data collection in this study. Results showed significant group differences for copy, recall, motor, and perceptual subscales of BGT-II in these samples, where patients with occipital lobe epilepsy and patients with migraine having significantly lower scores than healthy individuals. Also, patients with occipital lobe epilepsy had significantly poorer scores in all subscales of the BGT-II in comparison with the patients with migraine. There were no significant differences with regard to gender and educational level when considering dependent variables in the present study.

Cognitive decline is evident in the elderly and it affects speech perception and foreign language learning. A listen-and-repeat training with a challenging speech sound contrast was earlier found to be effective in young monolingual adults and even in advanced L2 university students at the attentive and pre-attentive levels. This study investigates foreign language speech perception in the elderly with the same protocol used with the young adults. Training effects were measured with attentive behavioural measures (N = 9) and with electroencephalography measuring the pre-attentive mismatch negativity (MMN) response (N = 10). Training was effective in identification, but not in discrimination and there were no changes in the MMN. The most attention demanding perceptual functions which benefit from experience-based linguistic knowledge were facilitated through training, whereas pre-attentive processing was unaffected. The elderly would probably benefit from different training types compared to younger adults.

Here, we provide an analysis of the microsaccades that occurred during continuous visual search and targeting of small faces that we pasted either into cluttered background photos or into a simple gray background. Subjects continuously used their eyes to target singular 3-degree upright or inverted faces in changing scenes. As soon as the participant’s gaze reached the target face, a new face was displayed in a different and random location. Regardless of the experimental context (e.g. background scene, no background scene), or target eccentricity (from 4 to 20 degrees of visual angle), we found that the microsaccade rate dropped to near zero levels within only 12 milliseconds after stimulus onset. There were almost never any microsaccades after stimulus onset and before the first saccade to the face. One subject completed 118 consecutive trials without a single microsaccade. However, in about 20% of the trials, there was a single microsaccade that occurred almost immediately after the preceding saccade’s offset. These microsaccades were task oriented because their facial landmark targeting distributions matched those of saccades within both the upright and inverted face conditions. Our findings show that a single feedforward pass through the visual hierarchy for each stimulus is likely all that is needed to effectuate prolonged continuous visual search. In addition, we provide evidence that microsaccades can serve perceptual functions like correcting saccades or effectuating task-oriented goals during continuous visual search.

Physical education plays a fundamental role in the integral development of the student, enabling cognitive, psychomotor...

Perceptual organization is an important part of visual and auditory information processing. In the case of visual occlusion, whether the loss of information in images could be recovered and thus perceptually closed affects object recognition. In particular, many elderly subjects have defects in object recognition ability, which may be closely related to the abnormalities of perceptual functions. This phenomenon even can be observed in the early stage of dementia. Therefore, studying the neural mechanism of perceptual closure and its relationship with sensory and cognitive processing is important for understanding how the human brain recognizes objects, inspiring the development of neuromorphic intelligent algorithms of object recognition. In this study, a new experiment was designed to explore the realistic process of perceptual closure under occlusion and intact conditions of faces and building. The analysis of the differences in ERP components P1, N1, and Ncl indicated that the subjective awareness of perceptual closure mainly occurs in Ncl, but incomplete information has been processed and showed different manners compared to complete stimuli in N170 for facial materials. Although occluded, faces, but not buildings, still maintain the specificity of perceptual processing. The Ncl by faces and buildings did not show significant differences in both amplitude and latency, suggesting a “completing” process regardless of categorical features.

Synopsis The olfactory cortex includes all regions of the brain receiving direct input from the olfactory bulb, and includes the piriform cortex as largest component. The olfactory cortex contributes to all aspects of odor perception including odor intensity and quality coding, odor hedonics, and odor memory. Many of the functions of piriform cortex require neural plasticity, including formation of experience-dependent, distributed ensembles of neurons responsive to a particular odor. Finally, the reliance on plasticity processes for basic perceptual functions makes the piriform cortex, and odor perception, susceptible to disorders such as Alzheimer's disease.

The enormous progress of knowledge and medical technologies allows now to rescue extremely immature newborns, i.e. those weighing less than 1000 g, born of a pregnancy with a duration of less than 28 weeks. The prevalence of premature babies weighing 1,000–1,500 g from a pregnancy lasting 28–32 weeks is about 1% in Poland. Premature termination of pregnancy is a serious problem, especially in the aspect of the future fate of the child. Threats, however, are subject to some evolution along with the advancement of pregnancy. The diseases and complications of the neonatal period, being an important element affecting the prognosis as to the life and health of the baby born prematurely, include brain damage, breathing disorders, circulatory disorders, digestive disorders and irregularities within the sensory organs. Speech therapists face more and more often problems affecting prematurely born children concerning the dysfunction of sensory analyzers, which in a significant way translates into cognitive functioning and, consequently, the process of language acquisition. Premature babies require diagnostics and stimulation as prevention of cognitive and communication disorders should be implemented as soon as possible. The combination of early medical intervention and early stimulation or, in extreme cases, of consistently conducted neurobiological therapy seems to have the greatest impact on the developmental chances of the quality of life of this group of children and their families. Dzięki ogromnemu postępowi wiedzy i technologiom medycznym ratuje się obecnie skrajnie niedojrzałe noworodki – nawet te o masie ciała poniżej 1000 g, urodzone z ciąży o czasie trwania krótszym niż 28 tygodni. Częstość urodzeń wcześniaków o masie ciała 1000–1500 g z ciąży trwającej 28–32 tygodnie wynosi w Polsce około 1%. Przedwczesne zakończenie ciąży stanowi poważny problem, szczególnie w aspekcie dalszych losów dziecka. Zagrożenia podlegają jednak pewnej ewolucji wraz z zaawansowaniem ciąży. Do powikłań okresu noworodkowego, będących istotnym elementem wpływającym na rokowania dotyczące życia i zdrowia noworodka urodzonego przedwcześnie, należą: uszkodzenia mózgu, zaburzenia oddychania, krążenia, zaburzenia pokarmowe, nieprawidłowości w obrębie narządów zmysłów. W praktyce logopedycznej spotykamy się coraz częściej z problemami dotykającymi dzieci przedwcześnie urodzonych, dotyczącymi między innymi dysfunkcji analizatorów zmysłów, co w istotny sposób przekłada się na funkcjonowanie poznawcze, a w konsekwencji na proces nabywania języka. Wcześniaki wymagają jak najwcześniejszej diagnostyki oraz stymulacji jako profilaktyki zaburzeń poznawczych i komunikacyjnych. Połączenie wczesnej interwencji medycznej i wczesnej stymulacji lub w skrajnych przypadkach konsekwentnie prowadzonej terapii neurobiologicznej zdaje się mieć największy wpływ na szanse rozwojowe i jakość życia tej grupy dzieci i ich rodzin.

The existence of a free will is fiercely debated in neuroscience and philosophy. The debate has great impact on society and our self-understanding as human beings. Behavioral and electrophysiological data have challenged the intuitive assumption that human behavior is the result of conscious intentions. This notion has important implications for delusions of control in schizophrenia, where patients experience bodily movements as not being controlled by themselves. Current theories explain control delusions as a deficit to perceive certain aspects of motor control, but many findings are inconsistent with this idea. Here, an alternative view is proposed: Control delusions might be triggered by an even more veridical perception of the temporal order of intentions and actions. This hypothesis is supported by evidence that (a) conscious intentions in healthy subjects are often based on retrospective inferences, (b) temporal recalibrations of conscious percepts occur in healthy subjects and are disturbed in schizophrenia and (c) basic perceptual functions of schizophrenic patients are less influenced by expectations and therefore they can sometimes be closer to physical reality than those of healthy subjects.

Cognitive approaches to training for the detection of improvised explosive devices (IED’s) are of increasing importance. However, there is a question as to the degree to which such training might interfere with other important law enforcement (LE) functions in the field, and the degree to which such training might enhance other important cognitive/perceptual functions. A promising cognitive approach to IED training, the SMOKE system, was provided to respondents, who then responded to shoot/no-shoot decisions, important LE situations of increasing relevance. It was shown that SMOKE training did not interfere with shoot/no-shoot decisions. However, those with SMOKE training performed better than control respondents on eyewitness memory for the perpetrator of a given crime in field-valid scenes. This indicates that cognitively based training may enhance vigilance and resultant memory in field situations.

A large body of research demonstrated that individuals with attention deficit hyperactivity disorder (ADHD) suffer from various neuropsychological deficits. In contrast, less is known and only divergent evidence exists on perceptual functions of individuals with ADHD. This is problematic as neuropsychological and perceptual functions are closely interrelated and are often difficult to disentangle in behavioral assessments. This study presents the conduct and results of a systematic literature review on perceptual functions in children and adults with ADHD. This review considers studies using psychophysical methods (objective measurements) and self- and informant reports (subjective measurements). Results indicate that individuals with ADHD have altered perceptual functions in various domains as compared to typically developing individuals. Increased perceptual functions in individuals with ADHD were found with regard to olfactory detection thresholds, whereas reduced perceptual functions were evident for aspects of visual and speech perception. Moreover, individuals with ADHD were found to experience discomfort to sensory stimuli at a lower level than typically developing individuals. Alterations of perceptual functions in individuals with ADHD were shown to be moderated by various factors, such as pharmacological treatment, cognitive functions, and symptom severity. We conclude by giving implications for daily life functioning and clinical practice.

Individuals with ASD have abnormal motor and perceptual functions that do not currently form diagnostic criteria of ASD, but nevertheless may affect everyday behaviour. Temporal processing seems to be one of such non-diagnostic yet impaired domains, although the lack of systematic studies testing different aspects of timing in the same sample of participants prevents a conclusive assessment of whether there is a generalized temporal deficit in ASD associated with diagnostic symptoms. 17 children diagnosed with ASD and 18 typically developing age- and IQ-matched controls carried out a set of motor and perceptual timing tasks: free tapping, simultaneity judgment, auditory duration discrimination, and verbal duration estimation. Parents of participants filled in a questionnaire assessing the sense and management of time. Children with ASD showed faster and more variable free tapping than controls. Auditory duration discrimination thresholds were higher in the ASD group than controls in a sub-second version of the task, while there were no group differences in a supra-second discrimination of intervals. Children with ASD showed more variable thresholds of simultaneity judgment, and they received lower parental scores for their sense and management of time. No group differences were observed in the verbal duration estimation task in the minute-range. Different timing functions were correlated in the ASD group but not among controls, whilst several timing measures correlated with ASD symptoms. We conclude that children with ASD show a broad range of abnormalities in temporal processing tasks including motor timing, perceptual timing, and temporal perspective.

The idea that the mind might be composed of distinct conscious entities goes back at least to the mid-19th century, and was at first based on the bilateral symmetry of the brain, with each side seemingly a mirror-image replica of the other. This led to early speculation as to whether section of the forebrain commissures might lead to separate, independent consciousnesses. This was not put to the test until the 1960s, first in commissurotomized cats and monkeys, and then in humans who had undergone commissurotomy for the relief of intractable epilepsy. Initial results did indeed suggest independent consciousness in each separated hemisphere, but later findings have also revealed a degree of mental unity, especially in some perceptual functions and in motor control. Some of these findings might be interpreted in terms of subcortical connections or external cross-cuing, and also address questions about the nature of consciousness in a more concrete way.

The ability to discriminate phonemes varying in spectral and temporal attributes constitutes one of the most basic intrinsic elements underlying language learning mechanisms. Since previous work has consistently shown that professional musicians are characterized by perceptual and cognitive advantages in a variety of language-related tasks, and since vowels can be considered musical sounds within the domain of speech, here we investigated the behavioral and electrophysiological correlates of native vowel discrimination learning in a sample of professional musicians and non-musicians. We evaluated the contribution of both the neurophysiological underpinnings of perceptual (i.e., N1/P2 complex) and mnemonic functions (i.e., N400 and P600 responses) while the participants were instructed to judge whether pairs of native consonant-vowel (CV) syllables manipulated in the first formant transition of the vowel (i.e., from /tu/ to /to/) were identical or not. Results clearly demonstrated faster learning in musicians, compared to non-musicians, as reflected by shorter reaction times and higher accuracy. Most notably, in terms of morphology, time course, and voltage strength, this steeper learning curve was accompanied by distinctive N400 and P600 manifestations between the two groups. In contrast, we did not reveal any group differences during the early stages of auditory processing (i.e., N1/P2 complex), suggesting that faster learning was mediated by an optimization of mnemonic but not perceptual functions. Based on a clear taxonomy of the mnemonic functions involved in the task, results are interpreted as pointing to a relationship between faster learning mechanisms in musicians and an optimization of echoic (i.e., N400 component) and working memory (i.e., P600 component) functions.

Surround modulation (SM) is a fundamental property of sensory neurons in many species and sensory modalities. SM is the ability of stimuli in the surround of a neuron's receptive field (RF) to modulate (typically suppress) the neuron's response to stimuli simultaneously presented inside the RF, a property thought to underlie optimal coding of sensory information and important perceptual functions. Understanding the circuit and mechanisms for SM can reveal fundamental principles of computations in sensory cortices, from mouse to human. Current debate is centered over whether feedforward or intracortical circuits generate SM, and whether this results from increased inhibition or reduced excitation. Here we present a working hypothesis, based on theoretical and experimental evidence, that SM results from feedforward, horizontal, and feedback interactions with local recurrent connections, via synaptic mechanisms involving both increased inhibition and reduced recurrent excitation. In particular, strong and balanced recurrent excitatory and inhibitory circuits play a crucial role in the computation of SM.

We used fMRI to dissociate decisional and perceptual functions in color categorization. Participants viewed sequences of colored squares which varied in perceptual distance (0, 1 or 2 hue steps) and color (green, blue) and then judged whether one or two colors were present. Occipital, caudate, and anterior insula regions were active when more than one hue was presented, indicating a role in perceptual processing and attentional monitoring. Dorsolateral prefrontal cortex showed greater activity when two colors were present than a single color, indicating a role in coding color category. Cognitive control regions of the intraparietal sulcus and presupplementary motor area were sensitive to the interaction of decision and distance in perceptual space, indicating a role in combining these functions during decision making. These results support theories that colors are represented categorically at high levels of the cognitive hierarchy, and that visual cortex is sensitive to hue rather than color category.

Amblyopia is a neurodevelopmental visual disorder arising from decorrelated binocular experience during the critical periods of development. The hallmark of amblyopia is reduced visual acuity and impairment in binocular vision. The consequences of amblyopia on various sensory and perceptual functions have been studied extensively over the past 50 years. Historically, relatively fewer studies examined the impact of amblyopia on visuomotor behaviours; however, research in this area has flourished over the past 10 years. Therefore, the aim of this review paper is to provide a comprehensive review of current knowledge about the effects of amblyopia on eye movements, upper limb reaching and grasping movements, as well as balance and gait. Accumulating evidence indicates that amblyopia is associated with considerable deficits in visuomotor behaviour during amblyopic eye viewing, as well as adaptations in behaviour during binocular and fellow eye viewing in adults and children. Importantly, due to amblyopia heterogeneity, visuomotor development in children and motor skill performance in adults may be significantly influenced by the etiology and clinical features, such as visual acuity and stereoacuity. Studies with larger cohorts of children and adults are needed to disentangle the unique contribution of these clinical characteristics to the development and performance of visuomotor behaviours.

In psychology and neuroscience it is common to describe cognitive systems as input/output devices where perceptual and motor functions are implemented in a purely feedforward, open-loop fashion. On this view, perception and action are often seen as encapsulated modules with limited interaction between them. While embodied and enactive approaches to cognitive science have challenged the idealisation of the brain as an input/output device, we argue that even the more recent attempts to model systems using closed-loop architectures still heavily rely on a strong separation between motor and perceptual functions. Previously, we have suggested that the mainstream notion of modularity strongly resonates with the separation principle of control theory. In this work we present a minimal model of a sensorimotor loop implementing an architecture based on the separation principle. We link this to popular formulations of perception and action in the cognitive sciences, and show its limitations when, for instance, external forces are not modelled by an agent. These forces can be seen as variables that an agent cannot directly control, i.e., a perturbation from the environment or an interference caused by other agents. As an alternative approach inspired by embodied cognitive science, we then propose a nonmodular architecture based on the active inference framework. We demonstrate the robustness of this architecture to unknown external inputs and show that the mechanism with which this is achieved in linear models is equivalent to integral control., Comment: Accepted at IJCNN 2019

This study captured substitution of non-linguistic perceptual functions without awareness. Eighty participants were divided into four groups. All groups were exposed to a respondent-type training procedure in which nine letters were paired with words; four of those words were homophones to numbers for the experimental groups and not for the control groups. Following training, all groups were exposed to a testing condition. One experimental and one control group were given a series of simple mathematical problems containing an unknown shown as a letter. Their task was to substitute the letter for a number. The other experimental and control groups were presented with a simultaneous matching-to-sample test. The results were analyzed in terms of concordance between the number selected and the correspondent homophone word that had previously been trained. Significant differences were found between the experimental and control groups for two of the four homophone numbers, demonstrating substitution of ...

Pain is a very relevant function for our survival and its alteration leads to important consequences for people's lives. In the last decades, researchers have started to investigate pain from a neurocognitive and neuropsychologic perspective, showing some important similarities and differences with other cognitive and perceptual functions. The complexity of pain perception, due to its multicomponential nature, has led to the need to interpret pain within a multisensory frame of reference. That is, this function and its neural foundation cannot be fully understood without taking into consideration the processing of other information that is concurrently presented together with noxious stimuli. The extant research in this field has shown that the parietal cortex plays a major role in pain perception, due to its involvement in the integration of information coming from different sources, to the support of body ownership, and to its role in sustaining spatial attention and awareness. It is likely that this neurocognitive knowledge will lead to better treatments of chronic and acute pain in the future.

Sound is a potent elicitor of emotions. Auditory core, belt and parabelt regions have anatomical connections to a large array of limbic and paralimbic structures which are involved in the generation of affective activity. However, little is known about the functional role of auditory cortical regions in emotion processing. Using functional magnetic resonance imaging and music stimuli that evoke joy or fear, our study reveals that anterior and posterior regions of auditory association cortex have emotion-characteristic functional connectivity with limbic/paralimbic (insula, cingulate cortex, and striatum), somatosensory, visual, motor-related, and attentional structures. We found that these regions have remarkably high emotion-characteristic eigenvector centrality, revealing that they have influential positions within emotion-processing brain networks with "small-world" properties. By contrast, primary auditory fields showed surprisingly strong emotion-characteristic functional connectivity with intra-auditory regions. Our findings demonstrate that the auditory cortex hosts regions that are influential within networks underlying the affective processing of auditory information. We anticipate our results to incite research specifying the role of the auditory cortex-and sensory systems in general-in emotion processing, beyond the traditional view that sensory cortices have merely perceptual functions.

Intuitive cognition mimics the basic parallel-interactive connectivity of the nervous system. This chapter examines several simple artificial neural networks that can imitate some basic perceptual functions of the human brain, such as face and handwriting recognition. Yet even in lower animals, perception is more complex than simple artificial neural networks suggest. After an overview of complexity theory, I offer a more complicated model based on the work of Walter Freeman, which is grounded in complexity theory and allows for the much richer connectivity of the human brain. It argues that perception occurs before awareness and is strongly influenced by emotional/motivational factors. Under their guidance, perception in animals as well as humans is directed as much by internal needs and goals, by the meaning of objects, as it is by external objects and events. The model can begin to account for both the stability of ordinary human perception as well its dramatic reorganization in certain experiences of intuition.

Objective: The aim of this study was to perform a usability test for CPAD (Cognitive Perceptual Assessment for Driving) and improve it based on the test results. Background: The cognitive perceptual assessment for driving is a computer-based assessment tool to assess the driving capacity of people with brain-damages. It may be a good tool for evaluating the brain-damaged drivers" safe driving capabilities and screening cognitive and perceptual deficits related to driving. We performed a usability test to improve the CPAD based on the result. Method: Both the software consisting of 8 sub-tests (depth perception, sustained attention, divided attention, stroop test, field dependency, digit span, trail making A, trail making B) and the hardware including the input and output devices (joystick, mouse, keyboard, touch screen) were evaluated through user interviews. Also we identified the problems and issues in using them by observing the participants performing the CPAD tasks. Results: Based on the results, the task instructions were visually and auditorily improved and more practice examples were added to help the users understand the instructions better and increase the input accuracy, a response time window was added and the joystick and touch screen were simplified, which made it easier for the user to perform the CAPD tasks. Conclusion: User discomforts were minimized by improving the task environment, unless it had affected the evaluation criteria. Application: We plan to distribute the improved version of the CPAD to the regional rehabilitation hospitals, and the driving support centers for people with disabilities throughout the country, so it could be used as an evaluation tool for disabled drivers" cognitive and perceptual functions.

Recent work suggests that memory representations may guide basic perceptual functions, such as figure-ground perception. In three studies we assessed top-down contributions to figure-ground perception in typical development and in two developmental disorders: Down syndrome (DS) and autism (ASD). We investigated how figure-ground segregation is modulated by high-level cues (i.e., memory representations) and low-level cues (i.e., convexity and surface integration). Study 1 results showed that both high-level and low-level contributions to figure-ground perception are functional by the age of 4 years. In Study 2, individuals with DS exhibited intact figure-ground segregation based on low level cues when compared with mental age–matched participants, but they showed attenuated effects of high-level memory cues on figure-ground assignment. In Study 3, individuals with ASD showed intact effects of both high-level and low-level cues on figure-ground perception, counter to previous suggestions that high-level influences on perception are usually impaired in ASD.

Objective: To investigate the neuropsychological visual motor perceptual functions of children with cleft lip and palate. Methods: Observational, prospective, cross-sectional, descriptive study, held at a referral hospital for craniofacial anomalies in the period from August 2012 to February 2013. The study included 50 children of both sexes, 25 of them with cleft lip and palate, comprising GI, and 25 children as control group, GII, aged 10 years. For evaluation, the study applied the Coloured Progressive Matrices, the Visual Motor Gestalt Test, and Neuropsychological Subtests Examination, followed by statistical evaluation, using promotion and correlation tests (Fischer) at 5% significance level. Results: The group with cleft lip and palate showed performance below the expected average for their age, the group with the trans-incisive foramen cleft type being the most affected in the performance of visual motor perceptual competence. Pre- and post-foramen cleft types obtained average scores, with values matching the control group. Conclusion: Children with cleft lip and palate of trans-foramen type were found more liable to present disorders in visual motor functions. Furthermore, skills in the perceptual and constructive domains are related to performances classified below the expected mean for the age range in the target population.

The aspects affecting the academic success of students in mathematics include the level of informal mathematical knowledge and communication skills. Therefore this study analyses the influence of the level of perceptual (visual and auditory) functions on the development of pre-mathematical concepts in 71 Czech pre-school children. The survey was carried out using a standardised foreign test of early mathematical skills and a test of reading and writing risks. The results confirmed the tightness of the relationship between the two variables, which can be described as “medium” addiction.

To effectively perform visual tasks like detecting contours, the visual system normally needs to integrate multiple visual features. Sufficient physiological studies have revealed that for a large number of neurons in the primary visual cortex (V1) of monkeys and cats, neuronal responses elicited by the stimuli placed within the classical receptive field (CRF) are substantially modulated, normally inhibited, when difference exists between the CRF and its surround, namely, non-CRF, for various local features. The exquisite sensitivity of V1 neurons to the center-surround stimulus configuration is thought to serve important perceptual functions, including contour detection. In this paper, we propose a biologically motivated model to improve the performance of perceptually salient contour detection. The main contribution is the multifeature-based center-surround framework, in which the surround inhibition weights of individual features, including orientation, luminance, and luminance contrast, are combined according to a scale-guided strategy, and the combined weights are then used to modulate the final surround inhibition of the neurons. The performance was compared with that of single-cue-based models and other existing methods (especially other biologically motivated ones). The results show that combining multiple cues can substantially improve the performance of contour detection compared with the models using single cue. In general, luminance and luminance contrast contribute much more than orientation to the specific task of contour extraction, at least in gray-scale natural images.

Visual perceptual learning is widely assumed to reflect plastic changes occurring along the cerebro-cortical visual pathways, including at the earliest stages of processing, though increasing evidence indicates that higher-level brain areas are also involved. Here we addressed the possibility that the cerebellum plays an important role in visual perceptual learning. Within the realm of motor control, the cerebellum supports learning of new skills and recalibration of motor commands when movement execution is consistently perturbed (adaptation). Growing evidence indicates that the cerebellum is also involved in cognition and mediates forms of cognitive learning. Therefore, the obvious question arises whether the cerebellum might play a similar role in learning and adaptation within the perceptual domain. We explored a possible deficit in visual perceptual learning (and adaptation) in patients with cerebellar damage using variants of a novel motion extrapolation, psychophysical paradigm. Compared to their age- and gender-matched controls, patients with focal damage to the posterior (but not the anterior) cerebellum showed strongly diminished learning, in terms of both rate and amount of improvement over time. Consistent with a double-dissociation pattern, patients with focal damage to the anterior cerebellum instead showed more severe clinical motor deficits, indicative of a distinct role of the anterior cerebellum in the motor domain. The collected evidence demonstrates that a pure form of slow-incremental visual perceptual learning is crucially dependent on the intact cerebellum, bearing the notion that the human cerebellum acts as a learning device for motor, cognitive and perceptual functions. We interpret the deficit in terms of an inability to fine-tune predictive models of the incoming flow of visual perceptual input over time. Moreover, our results suggest a strong dissociation between the role of different portions of the cerebellum in motor versusnon-motor functions, with only the posterior lobe being responsible for learning in the perceptual domain. © 2014.

Understanding the nature and extent of neural plasticity in humans remains a key challenge for neuroscience. Importantly, however, a precise characterization of plasticity and its underlying mechanism has the potential to enable new approaches for enhancing reorganization of cortical function. Investigations of the impairment and subsequent recovery of cognitive and perceptual functions following early-onset cortical lesions in humans provide a unique opportunity to elucidate how the brain changes, adapts, and reorganizes. Specifically, here, we focus on restitution of visual function, and we review the findings on plasticity and re-organization of the ventral occipital temporal cortex (VOTC) in published reports of 46 patients with a lesion to or resection of the visual cortex early in life. Findings reveal that a lesion to the VOTC results in a deficit that affects the visual recognition of more than one category of stimuli (faces, objects and words). In addition, the majority of pediatric patients show limited recovery over time, especially those in whom deficits in low-level vision also persist. Last, given that neither the equipotentiality nor the modularity view on plasticity was clearly supported, we suggest some intermediate possibilities in which some plasticity may be evident but that this might depend on the area that was affected, its maturational trajectory as well as its structural and functional connectivity constraints. Finally, we offer suggestions for future research that can elucidate plasticity further.

The vestibular system sub-serves a number of reflex and perceptual functions, comprising the peripheral apparatus, the vestibular nerve, the brainstem and cerebellar processing circuits, the thalamic relays, and the vestibular cerebral cortical network. This system provides signals of self-motion, important for gaze and postural control, and signals of traveled distance, for spatial orientation, especially in the dark. Current evidence suggests that certain aspects of this multi-faceted system may deteriorate with age and sometimes with severe consequences, such as falls. Often the deterioration in vestibular functioning relates to how the signal is processed by brain circuits rather than an impairment in the sensory transduction process. We review current data concerning age-related changes in the vestibular system, and how this may be important for clinicians dealing with balance disorders.

Schizophrenia is characterized by anomalous perceptual experiences (e.g., sensory irritation, inundation, and flooding) and specific alterations in visual perception. We aimed to investigate the effects of short-term antipsychotic medication on these perceptual alterations. We assessed 28 drug-naïve first episode patients with schizophrenia and 20 matched healthy controls at baseline and follow-up 8 weeks later. Contrast sensitivity was measured with steady- and pulsed-pedestal tests. Participants also received a motion coherence task, the Structured Interview for Assessing Perceptual Anomalies (SIAPA), and the Repeatable Battery for the Assessment of Neuropsychological Status (RBANS). Proton magnetic resonance spectroscopy was used to measure gamma-aminobutyric acid (GABA) levels in the occipital cortex (GABA/total creatine [Cr] ratio). Results revealed that, comparing baseline and follow-up values, patients with schizophrenia exhibited a marked sensitivity reduction on the steady-pedestal test at low spatial frequency. Anomalous perceptual experiences were also significantly ameliorated. Antipsychotic medications had no effect on motion perception. RBANS scores showed mild improvements. At baseline, but not at follow-up, patients with schizophrenia outperformed controls on the steady-pedestal test at low spatial frequency. The dysfunction of motion perception (higher coherence threshold in patients relative to controls) was similar at both assessments. There were reduced GABA levels in schizophrenia at both assessments, which were not related to perceptual functions. These results suggest that antipsychotics dominantly affect visual contrast sensitivity and anomalous perceptual experiences. The prominent dampening effect on low spatial frequency in the steady-pedestal test might indicate the normalization of putatively overactive magnocellular retino-geniculo-cortical pathways.

The hippocampus has frequently been viewed as a core long-term memory structure, separate from brain structures mediating other cognitive functions such as working memory and perception. Much the same is true of other medial temporal lobe (MTL) structures such as the parahippocampal gyrus and the perirhinal cortex. Recent evidence suggests, instead, that these latter structures are also important for certain perceptual functions, leading many to propose a representational account of MTL that defines its functions in terms of what is being represented, rather than how long this representation lasts, or which psychological function is being invoked. We discuss a common framework within which perception and memory are seen as involving many, if not most, of the structures in the ventral representational stream, critically dependent on extensive feedforward and feedback processes. A variety of perceptual and memorial phenomena are discussed within this framework, and it is concluded that the hippocampus is in many ways like its neighbors in the MTL, yet has some distinct properties that account for its unique role in episodic memory.

Visual judgments critically depend on (1) the detection of meaningful items from cluttered backgrounds and (2) the discrimination of an item from highly similar alternatives. Learning and experience are known to facilitate these processes, but the specificity with which these processes operate is poorly understood. Here we use psychophysical measures of human participants to test learning in two types of commonly used tasks that target segmentation (signal-in-noise, or “coarse” tasks) versus the discrimination of highly similar items (feature difference, or “fine” tasks). First, we consider the processing of binocular disparity signals, examining performance on signal-in-noise and feature difference tasks after a period of training on one of these tasks. Second, we consider the generality of learning between different visual features, testing performance on both task types for displays defined by disparity, motion, or orientation. We show that training on a feature difference task also improves performance on signal-in-noise tasks, but only for the same visual feature. By contrast, training on a signal-in-noise task has limited benefits for fine judgments of the same feature but supports learning that generalizes to signal-in-noise tasks for other features. These findings indicate that commonly used signal-in-noise tasks require at least three distinct components: feature representations, signal-specific selection, and a generalized process that enhances segmentation. As such, there is clear potential to harness areas of commonality (both within and between cues) to improve impaired perceptual functions.

The cerebral cortex changes throughout the lifespan, and the cortical grey matter in many brain regions becomes thinner with advancing age. Effects of aging on cortical thickness have been observed in many brain regions, including areas involved in basic perceptual functions such as processing visual inputs. An important property of early visual cortices is their topographic organization – the cortical structure of early visual areas forms a topographic map of retinal inputs. Primary visual cortex (V1) is considered to be the most basic cortical area in the visual processing hierarchy, and is topographically organized from posterior (central visual representation) to anterior (peripheral visual representation) along the calcarine sulcus. Some studies have reported strong age-dependent cortical thinning in portions of V1 that likely correspond to peripheral visual representations, while there is less evidence of substantial cortical thinning in central V1. However, the effect of aging on cortical thickness in V1 as a function of its topography has not been directly investigated. To address this gap in the literature, we estimated the cortical thickness of different eccentricity sectors in V1 using T1-weighted MRI scans acquired from groups of healthy younger and older adults, and then assessed whether between-group differences in V1 cortical thickness depended on cortical eccentricity. These analyses revealed age-dependent cortical thinning specific to peripheral visual field representations in anterior portions of V1, but did not provide evidence for age-dependent cortical thinning in other portions of V1. Additional analyses found similar effects when analyses were restricted to the gyral crown, sulcul depth, and sulcul wall, indicating that these effects are not likely due to differences in gyral/sulcul contributions to our regions of interest. Importantly, this finding indicates that age-dependent changes in cortical structure may differ among functionally distinct zones within larger canonical cortical areas. Likely relationships to known age-related declines in visual performance are discussed to provide direction for future research in this area.

Background Functional magnetic resonance imaging (fMRI) resting-state studies show generalized social anxiety disorder (gSAD) is associated with disturbances in networks involved in emotion regulation, emotion processing, and perceptual functions, suggesting a network framework is integral to elucidating the pathophysiology of gSAD. However, fMRI does not measure the fast dynamic interconnections of functional networks. Therefore, we examined whole-brain functional connectomics with electroencephalogram (EEG) during resting-state. Methods Resting-state EEG data was recorded for 32 patients with gSAD and 32 demographically-matched healthy controls (HC). Sensor-level connectivity analysis was applied on EEG data by using Weighted Phase Lag Index (WPLI) and graph analysis based on WPLI was used to determine clustering coefficient and characteristic path length to estimate local integration and global segregation of networks. Results WPLI results showed increased oscillatory midline coherence in the theta frequency band indicating higher connectivity in the gSAD relative to HC group during rest. Additionally, WPLI values positively correlated with state anxiety levels within the gSAD group but not the HC group. Our graph theory based connectomics analysis demonstrated increased clustering coefficient and decreased characteristic path length in theta-based whole brain functional organization in subjects with gSAD compared to HC. Conclusions Theta-dependent interconnectivity was associated with state anxiety in gSAD and an increase in information processing efficiency in gSAD (compared to controls). Results may represent enhanced baseline self-focused attention, which is consistent with cognitive models of gSAD and fMRI studies implicating emotion dysregulation and disturbances in task negative networks (e.g., default mode network) in gSAD., Highlights • Social anxiety disorder is associated with disturbances in intrinsic networks. • Intrinsic networks were examined with electroencephalogram and graph theory. • Social anxiety was associated with theta-dependent interconnectivity.

Menstrual cycle-dependent changes have been reported for a variety of functions, including cognition, attention, emotion, inhibition, and perception. For several of these functions, an effect of hormonal contraceptives has also been discussed. Cognitive, attentional, emotional, inhibitory, and perceptual functions have been linked to distinct intrinsic connectivity networks during the resting state. However, changes in resting-state connectivity across the menstrual cycle phase and due to hormonal contraceptive use have only been investigated in two selected networks and without controlling for the type of hormonal contraceptives. In the present study, we demonstrate menstrual cycle and hormonal contraceptive-dependent changes in several intrinsic connectivity networks, including networks that have been related to emotion processing, olfaction, audition, vision, coordination, and two lateralized frontoparietal networks related to a variety of cognitive functions. These changes parallel behavioral changes in the functions associated with these networks. Changes in connectivity and changes in behavior occur during the same cycle phases. Furthermore, hormonal contraceptive-dependent effects were observed in the same networks and same target sites as menstrual cycle-related changes and were dependent on the androgenicity of the progestin component contained in the hormonal contraceptive.

Human perception thresholds can improve through learning. Here we report findings challenging the fundamental 'practice makes perfect' basis of procedural learning theory, showing that brief reactivations of encoded visual memories are sufficient to improve perceptual discrimination thresholds. Learning was comparable to standard practice-induced learning and was not due to short training per se, nor to an epiphenomenon of primed retrieval enhancement. The results demonstrate that basic perceptual functions can be substantially improved by memory reactivation, supporting a new account of perceptual learning dynamics.

The steady-state visual evoked potential (SSVEP) is a powerful tool to study basic perceptual functions in the human electroencephalogram (EEG) (e.g. selective attention). The present study aimed at finding support for the SSVEP's sensitivity to higher cognitive functions (e.g. memory). We tagged pictures of meaningless objects with 15 Hz within a combined subsequent-memory and recognition-memory design. The EEG was recorded from 128 electrodes. The subsequent-memory design revealed that SSVEPs are influenced by encoding-related processes. In particular, successful encoding was associated with higher SSVEP amplitudes at central-parietal scalp electrodes and reduced activity at left occipital sites. Recognition memory led to higher SSVEP amplitudes at right temporal scalp regions and to an amplitude reduction at midline electrodes. For the first time it was demonstrated that the SSVEP technique is a useful tool to study memory encoding and retrieval. SSVEPs might reflect the ongoing dynamics within an externally driven and widespread task-relevant network. This offers remarkable possibilities for future research on electrophysiological correlates of mnemonic functioning.

This paper presents slippage length-and-direction perceptual functions via finger-pad cutaneous sensations, which were obtained from experiments where the linear plane moves at a constant speed while in contact with finger on an index finger pad. Two conditions were compared in this study: (1) double task condition, i.e., the speed and duration-time varied condition, (2) a pair of single task conditions, i.e., either the speed or the duration-time fixed and the remaining varied conditions. It was found that, for a systematic error, there was no significant difference in the length perceptual abilities between the two conditions, and subjects were also unable to perceive the lengths in the duration-time-fixed and speed-varied condition. They suggest that, although the subjects may perceive the lengths to some extent, they almost cannot perceive the slip speeds, but they may actually perceive speed-perturbed duration times. (2) The perceptual random errors of slipping direction were examined, and were quantified by the standard deviation of 20 degrees.

Adults learning new scripts have difficulty becoming automatic readers. They typically read haltingly, understand little of what they read, and may forget letter values. This article presents the hypothesis that halting reading among adult neoliterates is due to low-level perceptual functions in the brain that have a sensitive period. These may be related to feature integration; whether illiterate or educated, adults learning a new script may be perceiving letters as connected segments rather than unbreakable units. The time needed to resolve ambiguities and determine how the segments are combined may delay identification and result in letter-by-letter reading. This phenomenon could be called “adult neoliterate dyslexia.” It has received little research or attention, possibly because few adults need to learn new scripts. Also unschooled illiterates are rare in industrialized countries where most reading studies are carried out. Research is needed to probe into the neuropsychological origin of the adults’ fluency difficulty. Potential remedies may include action videogames and thousands of trials through computerized media.