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Speed in early visual processing

Michael Hanke, Frank Ohl, Christiane Tretter et al. · Digitalen Hochschulbibliothek Sachsen-Anhalt (Universitäts- und Landesbibliothek Sachsen-Anhalt) · 2008

Cited by 0Open access

Color processing in visual cortex

Charles D. Gilbert · 1992

Wavelength specific cells in visual cortex are grouped together into compartments that are interdigitated between other compartments specializing in form, movement and depth. The first evidence for a functional organization of color based on cortical area came from the work of Semir Zeki, who described an area prestriate cortex, known as area V4, that was enriched for color specific cells. Other cortical areas also contained wavelength selective cells, but the precise distribution of these cells eluded investigators for a number of years until the discovery by Margaret Wong- Riley that in area VI the enzyme cytochrome oxidase (CO) was distributed in a regular series of patches, as seen in tangential sections through the superficial cortical layers. Using CO histochemistry, David Hubei and Margaret Livingstone found that wavelength selective cells were located within these patches or "blobs", with broadband, orientation selective cells being found predominantly outside them. This lent support to the idea that color, as represented by wavelength selective cells, and form, as represented by orientation selective cells, were analyzed by separate, parallel pathways in the visual system. This left open, however, the question of how information about form and color might be attributed to a particular object, the so called "binding" problem, and also about how boundaries made by different colors could provide information about form. In fact, the existence of cells selective both for wavelength and for orientation had been known from a number of studies, and Ts'o and Gilbert found that such cells tended to lie at the boundaries of the CO blobs. With regard to the color selectivity found within the blobs, they found that cells sharing similar color opponency were grouped into columns, and that individual blobs specialized in either red-green or blue-yellow opponency.

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The "Gist" of Visual Processing

David Chan, Mary A. Peterson, S. Qian et al. · Journal of Vision · 2012

Visual information in humans is processed by two separate visual pathways. One is the magnocellular visual pathway (M-pathway), which carries high temporal frequency information but low spatial frequency information. The other is the parvocellular visual pathway (P-pathway), which carries low temporal information but high spatial information. Moshe Bar and colleagues (2007) presented participants with high and low spatial frequency images and found that participants made faster and more accurate categorization responses to the low spatial frequency images. They hypothesized this was due to low spatial frequency "gist" information being rapidly carried by the M-pathway that helps support rapid object perception. In order to directly test the involvement of the M-pathway in "gist" processing, we used red diffuse light, which selectively inhibits the M-pathway (e.g., West, Anderson, & Pratt, 2010) but leaves the P-pathway activity untouched. In our experiment, we presented participants with low and high spatial frequency images under either red or green (control condition) diffuse light and asked them to judge whether the object was larger or smaller than a shoebox. We replicated the original finding of an advantage in categorizing low spatial frequency images, and found this advantage existed under both green and red light conditions. Thus, it does not appear "gist" processing is uniquely carried by the M-pathway. In addition, we found that responses were much faster overall with red diffuse light than green diffuse light. Given that inhibiting one pathway can bias activity in the other pathway ((Yeshurun, 2004), the faster responses under red diffuse light may reflect a processing advantage is the object perception P-stream. In this case, processing with a single visual stream may provide faster responses than when two streams are working in parallel. Meeting abstract presented at VSS 2012

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VISUAL SENSORY PROCESSING DISORDER DETECTION

Suruchi Dedgaonkar · Mendeley Data · 2022

Screening tools play a vital role in sensory processing disorder detection. The automatic collection of features related to behavioral parameters and the response to given stimuli is possible with the recent technology. Real time stress related health parameters are collected as response to visual stimuli created with experts’ suggestions based on visual sensory processing related questionnaire. Body temperature and heart rate are obtained by smart watch. Probability distribution for seven facial expressions (Angry, Disgust, Fear, Happy, Neutral, Sad, Surprise) is retrieved from video captured during portrayed stimuli. Reduced questionnaire is filled by care takers or parents based on the observations. This data will help behavioral therapist to reduce time, efforts and number of screening sessions required for visual sensory processing disorder detection and tracking effectiveness of therapy.

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Spatial Scale in Visual Processing

Robert F. Hess · The MIT Press eBooks · 2003

Cited by 2

Computer Processing of Visual Data

William M. Hart · Archives of Ophthalmology · 1981

Machine algorithms have been developed for automated detection and characterization of glaucomatous defects in visual field records stored in a computer. Using elementary techniques of pattern analysis, the contours defining each visual field are described by a set of primitive graphic and type-descriptive features. A hierarchical structure of logical tests is then used to arrive at intermediate and higher-level conclusions. Decision procedures are tailored for the detection of features commonly found in glaucomatous visual fields. Application of these analysis procedures to a large group of visual field records having a broad range of glaucomatous defects shows a very high sensitivity for detection. Specificity is limited by the extent to which defects are "typical" or obey expected patterns of field loss.

Cited by 9

Screening for Visual Acuity, Visual Efficiency, and Visual Information Processing Problems

Mitchell Scheiman · 2024

In the first five chapters, I have tried to establish the importance of vision and the various ways in which vision can possibly interfere with occupational therapy progress. It is critical that an occupational therapist be aware of the characteristics of the visual system of any patient they are treating. Ideally, this information should be readily available before treatment begins. In most cases, however, no information or very limited information will be available. In a school system, the child may have been screened in the past by the school nurse. School screenings generally consist of only a test to screen for visual acuity problems, myopia, and high degrees of hyperopia and astigmatism. Early day care centers will often have medical records available that may include a screening performed by the pediatrician. This will most often consist of only an evaluation of eye health. In a hospital setting, an ophthalmological consultation may occur before the occupational therapist treats a patient. Even if this has been done, it is very likely that the only aspects of the visual system that will have been tested will be visual acuity, refractive error, and eye health. Very little attention is paid to binocular vision, accommodation, eye movements, and visual fields in acute care or rehabilitation hospitals. 1–4 Gianutsos, 2 a well-respected researcher and clinician in the area of rehabilitation of acquired brain injury, states: Generally, after brain injury, the visual system is not comprehensively evaluated, sometimes because there is a lack of articulated complaints due to impaired subjective experience or reduced cognition. Visual system evaluations are frequently neglected. Often referrals, if they are made at all, are made to ophthalmologists, reflecting the medical orientation of the delivery system. Ophthalmologists, however, are primarily concerned with the physiologic health of the eye. Important as this is for the survivor of brain trauma, further issues of concern for visual information processing pertain to the function of the full visual system.

Cited by 0

Screening for Visual Acuity, Visual Efficiency, and Visual Information Processing Problems

Mitchell Scheiman · 2024

In the first five chapters, I have tried to establish the importance of vision and the various ways in which vision can possibly interfere with occupational therapy progress. It is critical that an occupational therapist be aware of the characteristics of the visual system of any patient he or she is treating. Ideally, this information should be readily available before treatment begins. In most cases, however, no information or very limited information will be available. In a school system, the child may have been screened in the past by the school nurse. School screenings generally consist of only a test to screen for visual acuity problems, myopia, and high degrees of hyperopia and astigmatism. Early day care centers will often have medical records available that may include a screening performed by the pediatrician. This will most often consist of only an evaluation of eye health. In a hospital setting, an ophthalmological consultation may occur before the occupational therapist treats a patient. Even if this has been done, it is very likely that the only aspects of the visual system that will have been tested will be visual acuity, refractive error, and eye health. Very little attention is paid to binocular vision, accommodation, eye movements, and visual fields in acute care or rehabilitation hospitals. 1–4 Gianutsos, 2 a well-respected researcher and clinician in the area of rehabilitation of acquired brain injury, states: Generally, after brain injury, the visual system is not comprehensively evaluated, sometimes because there is a lack of articulated complaints due to impaired subjective experience or reduced cognition. Visual system evaluations are frequently neglected. Often referrals, if they are made at all, are made to ophthalmologists, reflecting the medical orientation of the delivery system. Ophthalmologists, however, are primarily concerned with the physiologic health of the eye. Important as this is for the survivor of brain trauma, further issues of concern for visual information processing pertain to the function of the full visual system. Table 6-1 Questions to Ask the Eye Doctor Before Referring a Patient Do you have experience working with learning disabled children? Do you have experience working with developmentally delayed, multiply handicapped, autistic, and physically impaired children? Do you have experience working with patients with acquired brain injury? Do you test accommodative amplitude and facility? Do you evaluate fusional vergence amplitude and facility? Do you evaluate visual information processing skills? Do you offer vision therapy as a service in your practice?

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Time Course Of Auditory Processing, Visual Processing, Language And Speech Processing

Muluk, Nuray Bayar, Yalcinkaya, Fulya · Hacettepe University Institutional Repository (hacettepe.edu.tr) · 2019

Each stimulus is processed in the brain at a certain speed/time. Hearing, vision and language are included in this process. Such as, the onset of language specific phonetic phonological analysis has been estimated at 100-200 ms. Listener the smaller the gap that can be detected. Such as, rapidly changing (gap) sounds such as /r/, /I/. There are need both short (20msec for phoneme duration signals) and long (200msec for syllable-duration signals) segments of speech. In hearing, language and speech processing functions, brain works together with all fields (auditory processing, memory, language and the image and speech recording area, etc.) synchronizely for seconds as the orchestra. If neurons can not participate this processing synchronizely, synchronization is corrupted. Processing time of information and synchronization work should be the basis for hearing, language and speech training. Phonetics in speech come to our ears in a few seconds through sound waves. If these sounds can not received within a few seconds, they get lost. If received, they were processed in the auditory pathway and brain in a few seconds. The purpose of this review is to draw attention that, if the sounds are received and processed within a few seconds, the training method used in speech training model should be intended for sounds' transmission and processing in a few seconds. In addition, all of the functions (auditory, view processing, memory and language) should be included into training by bottom-up approach. Auditory processing is the ability to listen, comprehend and respond to information that we hear through our auditory channels. It needs decoding of the neural message. Auditory processing involves attention to detection and identification of the signal; and decoding of the neural message. If we don't give full attention to heard things, listening difficulty ocuurs. In poor attention and listening conditions, rapid acoustic changes in speech can not be discriminated.

Cited by 2Open access

Plasticity of visual processing in the primary visual cortex

Sina Eileen Dominiak (7143497) · Figshare · 2024

<p dir="ltr">The sensory world is dynamic and constantly changing. The ability to react appropriately to these changes relies on the continuous and timely cortical processing of immediate sensory information, often in relation to previous experiences. This processing is plastic, but the circuit mechanisms that underlie this plasticity are not yet understood. Here, we investigated the short-term and long-term changes in responsivity of cortical neurons within the primary visual cortex (V1) of mice to further unravel the mechanisms behind cortical plasticity. We used two-photon microscopy to image layer 2/3 of V1 in awake mice expressing GCaMP6f in pyramidal cells (PCs) and ChrimsonR (an optogenetic activator) in somatostatin expressing interneurons (SSTs). Mice head-fixed on a treadmill, were exposed to high-contrast, drifting gratings in repeated 10 s trials during 6 sessions over 2 weeks. To change the relevance of the stimulus from redundant to important, a second group of mice was rewarded at the end of each stimulus presentation. We revealed, that on short timescales (seconds) PCs can decrease (depress) or increase (sensitize) the gain of their response to a high-contrast stimulus. Furthermore, we investigated the relation between these fast adaptive changes and the long-term changes occurring on timescales of days when a stimulus was repeatedly presented to an animal, putting a focus on the relevance of the stimulus. Whether or not the stimulus was rewarded, repetitive exposure to the stimulus caused a shift from depressing to sensitizing short-term adaptation within the PC population. Simultaneously, the number of stimulus-responsive PCs decreased in the non-rewarded condition, whereas they appeared stable across sessions when the stimulus predicted a reward. Optogenetic activation of SST cells allowed us to separate the population of PCs into 3 groups: Cells that showed a decrease, an increase, or no significant change in initial response to the stimulus under SST activation. In the rewarded condition, there was a significant increase in the number of PCs that increased their responsivity during SST cell activation whereas the number of PCs that decreased their response went down significantly. We propose that reward association with a repeated stimulus weakens direct inhibition to PCs from SSTs and increases disinhibition via the SST->PV->PC pathway.</p>

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Visual information processing for deep-sea visual monitoring system

Chunyan Ma, Xin Li, Yujie Li et al. · Cognitive Robotics · 2021

Due to the rising demand for minerals and metals, various deep-sea mining systems have been developed for the detection of mines and mine-like objects on the seabed. However, many of them contain some issues due to the diffusion of dangerous substances and radioactive substances in water. Therefore, efficient and accurate visual monitoring is expected by introducing artificial intelligence. Most recent deep-sea mining machines have little intelligence in visual monitoring systems. Intelligent robotics, e.g., deep learning-based edge computing for deep-sea visual monitoring systems, have not yet been established. In this paper, we propose the concept of a learning-based deep-sea visual monitoring system and use testbeds to show the efficiency of the proposed system. For example, to sense the underwater environment in real time, a large quantity of observation data, including captured images, must be transmitted from the seafloor to the ship, but large-capacity underwater communication is difficult. In this paper, we propose using deep compressed learning for real-time communication. In addition, we propose the gradient generation adversarial network (GGAN) to recover the heavily destroyed underwater images. In the application layer, wavelet-aware superresolution is used to show high-resolution images. Therefore, the development of an intelligent remote control deep-sea mining system with good convenience using deep learning applicable to deep-sea mining is expected.

Cited by 121Open access

Effects of visual information on audio-visual speech processing

Satoko Hisanaga, Kaoru Sekiyama, Tomohiko Igasaki et al. · The Proceedings of the Annual Convention of the Japanese Psychological Association · 2011

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Causal Role for Visual Cortex in Processing Visual Semantics

Kanqi Xie, Byoung-Tak Zhang · Communications in Humanities Research · 2025

This article reviewed previous studies testing for the causal or correlational relationship between modality-specific brain regions (e.g. motor cortex) and processing of corresponding perceptual-motor semantics. The proposed experiment aimed to investigate the functional role of visual cortex in understanding visual-associated words by studying the selective effect of transcranial direct current stimulation (tDCS) to primary visual cortex on response time (RT) to visual-associated words in lexical decision task. Participants will receive either sham or true anodal-tDCS, then perform the auditory lexical decision task to decide if the stimulus is a word in English or a pseudoword word. The experimental prediction was that compared to sham tDCS, anodal tDCS will affect the RTs with visual-associated word stimuli significantly more than to nonvisual-associated word stimuli. If the experimental prediction is supported, then this experiment would provide additional empirical evidence for the embodied simulation hypothesis, whilst establishing a causal role for visual cortex in visual semantic processing.

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Processing of visual textures in the mouse visual cortex

Federico Bolaños, Javier G. Orlandi, Akshay V. Jagadeesh et al. · Science Communications World Wide · 2022

Visual textures efficiently represent real-world information that is essential for perceptual tasks like pattern detection, object segmentation and classification. This information appears to be encoded in intermediate areas along the primate ventral visual stream (areas V2-V4), but how textural selectivity emerges at the circuit level, and whether the neural architectures that support texture processing are shared across mammalian species is currently unknown. We addressed these questions in the mouse by first examining the mouse’s perceptual ability to discriminate higher order texture statistics, and then by studying the neural substrate of texture processing along the ventral visual stream. We employed a new model to synthesize textures using convolutional neural networks pretrained for object recognition, and in addition we generated spectrally matched stimuli (scrambles) which shared the same low-order features as the textures. Mice could be trained to behaviorally discriminate textures from scrambles across different texture families. We then studied the neural underpinning of texture encoding in primary (V1) and secondary (LM) visual cortices by performing widefield and 2-photon GCaMP imaging. Both at the population and single cell level we observed that V1 and LM differentially responded to the textures compared to the scrambles, with response modulation in LM being higher than in V1. To examine whether these area differences were driven by the higher-order statistical features of texture stimuli, we trained a linear encoder model to predict responses of individual cells using the texture statistics as features. Overall, the model better captured the neural responses in LM than in V1, with larger weights associated with higher-order image statistics in area LM. In summary, our results provide evidence for texture vision in the mouse with a neural underpinning sharing encoding characteristics with the primate ventral visual stream, thus suggesting preserved neural principles for texture processing across mammalian species.

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Hemispheric dissociation of visual-pattern processing and visual rotation

Boris Suchan, L Yágüez, Gilbert Wunderlich et al. · Behavioural Brain Research · 2002

Cited by 63

Visual Motion Processing and Visual Sensorimotor Control in Autism

Yukari Takarae, Beatríz Luna, Nancy J. Minshew et al. · Journal of the International Neuropsychological Society · 2013

Abstract Impairments in visual motion perception and use of visual motion information to guide behavior have been reported in autism, but the brain alterations underlying these abnormalities are not well characterized. We performed functional magnetic resonance imaging (fMRI) studies to investigate neural correlates of impairments related to visual motion processing. Sixteen high-functioning individuals with autism and 14 age and IQ-matched typically developing individuals completed two fMRI tasks using passive viewing to examine bottom–up responses to visual motion and visual pursuit tracking to assess top–down modulation of visual motion processing during sensorimotor control. The autism group showed greater activation and faster hemodynamic decay in V5 during the passive viewing task and reduced frontal and V5 activation during visual pursuit. The observations of increased V5 activation and its faster decay during passive viewing suggest alterations in local V5 circuitries that may be associated with reduced GABAergic tone and inhibitory modulation. Reduced frontal and V5 activation during active pursuit suggest reduced top–down modulation of sensory processing. These results suggest that both local intrinsic abnormalities in V5 and more widely distributed network level abnormalities are associated with visual motion processing in autism. ( JINS , 2014, 20 , 113–122)

Cited by 65Open access

Interference processing within visual working memory

Rösner, Marlene · UB Bochum · 2023

In dieser Arbeit wurden die Prozesse, auf denen Aufmerksamkeitsverschiebungen im Arbeitsgedächtnis beruhen, untersucht. Generell konnte mit Hilfe des EEGs gezeigt werden, dass Aufmerksamkeitsverschiebungen im Arbeitsgedächtnis durch Hemmung unwichtiger Informationen gesteuert werden. Anschließend wurden die Rückorientierung von Aufmerksamkeit auf eine Aufgabe nach einer Unterbrechung untersucht. Hier konnte gezeigt werden, dass Unterschiede in elektrophysiologischer Aktivität zwischen den Hemisphären eine genaue Erfassung der Orientierung von einer Unterbrechung zurück zur Aufgabe ermöglichen. Zudem störten Unterbrechungen die Koordinierung verschiedener kognitiver Prozesse, die am Arbeitsgedächtnis beteiligt sind. Auch wurde untersucht wie sich die Verarbeitungen von Unterbrechungen im Alter verändert. Insgesamt wurde die Relevanz der Hemmung unwichtiger Informationen und der Koordination kognitiver Prozesse für das Funktionieren des Arbeitsgedächtnisses unterstrichen.

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Visual Form-Processing Deficits in Autism

Janine Spencer, Justin OʼBrien · Perception · 2006

People with autism have a number of reported deficits in object recognition and global processing. Is there a low-level spatial integration deficit associated with this? We measured spatial-form-coherence detection thresholds using a Glass stimulus in a field of random dots, and compared performance to a similar motion-coherence task. A coherent visual patch was depicted by dots separated by a rotational transformation in space (form) or space-time (motion). To measure parallel visual integration, stimuli were presented for only 250 ms. We compared detection thresholds for children with autism, children with Asperger syndrome, and a matched control group. Children with autism showed a significant form-coherence deficit and a significant motion-coherence deficit, while the performance of the children with Asperger syndrome did not differ significantly from that of controls on either task.

Cited by 87

Visual On-Line Analytical Processing (OLAP)

Marc H. Scholl, Svetlana Mansmann · Encyclopedia of Database Systems · 2009

Cited by 1

Visual Motion Processing in Macaque V2

Jiaming Hu, Heng Ma, Shude Zhu et al. · Cell Reports · 2018

In the primate visual system, direction-selective (DS) neurons are critical for visual motion perception. While DS neurons in the dorsal visual pathway have been well characterized, the response properties of DS neurons in other major visual areas are largely unexplored. Recent optical imaging studies in monkey visual cortex area 2 (V2) revealed clusters of DS neurons. This imaging method facilitates targeted recordings from these neurons. Using optical imaging and single-cell recording, we characterized detailed response properties of DS neurons in macaque V2. Compared with DS neurons in the dorsal areas (e.g., middle temporal area [MT]), V2 DS neurons have a smaller receptive field and a stronger antagonistic surround. They do not code speed or plaid motion but are sensitive to motion contrast. Our results suggest that V2 DS neurons play an important role in figure-ground segregation. The clusters of V2 DS neurons are likely specialized functional systems for detecting motion contrast.

Cited by 23Open access