T2 - Center for Neural Basis of Cognition
... Remapping occurs at early stages of the visual hierarchy. Corollary discharge has an impact far back into the system. Remapping implies widespread connectivity in which many neurons have rapid access to information well beyond the classical receptive field. Vision is an active process of building re ...
... Remapping occurs at early stages of the visual hierarchy. Corollary discharge has an impact far back into the system. Remapping implies widespread connectivity in which many neurons have rapid access to information well beyond the classical receptive field. Vision is an active process of building re ...
Visual areas and spatial summation in human visual cortex
... and V3. A second distinct central field representation Is visible at the fundus of the transverse occipital sulcus (TOS) where areas V3A and V3B are observed (Smith et al., 1998; Tootell et al., 1997). We have confirmed that a portion of this specific representation is within V3A by using angular re ...
... and V3. A second distinct central field representation Is visible at the fundus of the transverse occipital sulcus (TOS) where areas V3A and V3B are observed (Smith et al., 1998; Tootell et al., 1997). We have confirmed that a portion of this specific representation is within V3A by using angular re ...
Residual eye-movements in macaque and their effects on visual
... a sample from another eye. The trace in Fig. 3A shows a prominent modulation of about 0.8 min arc at the frequency of the pulse (1020min) with an additional less prominent modulation (0.3 min arc) at the frequency of respiration (240min). For the eye represented in Fig. 3B, movements produced by the ...
... a sample from another eye. The trace in Fig. 3A shows a prominent modulation of about 0.8 min arc at the frequency of the pulse (1020min) with an additional less prominent modulation (0.3 min arc) at the frequency of respiration (240min). For the eye represented in Fig. 3B, movements produced by the ...
Neuronal Interaction Dynamics in Cat Primary Visual Cortex
... illustrated by gray ellipses). The frame with the cross-hair illustrates the analyzed portion of the visual space (2.8 3 2.0). D –F, I llustration of the Gaussian interpolation method to construct the DPA. D1, The grid of stimuli used (36 circles, each 0.64° in diameter) to measure the RF profile of ...
... illustrated by gray ellipses). The frame with the cross-hair illustrates the analyzed portion of the visual space (2.8 3 2.0). D –F, I llustration of the Gaussian interpolation method to construct the DPA. D1, The grid of stimuli used (36 circles, each 0.64° in diameter) to measure the RF profile of ...
Chapter 21: Attention
... Neuroscience: Exploring the Brain, 3rd Ed, Bear, Connors, and Paradiso Copyright © 2007 Lippincott Williams & Wilkins ...
... Neuroscience: Exploring the Brain, 3rd Ed, Bear, Connors, and Paradiso Copyright © 2007 Lippincott Williams & Wilkins ...
Toward a Unified Theory of Visual Area V4
... was a color area were likely biased toward microelectrode recordings from color modules, while those reporting clear shape selectivity were likely biased toward recordings from noncolor modules (Conway and Tsao, 2006; Tanigawa et al., 2010). How does the presence of segregated functional domains imp ...
... was a color area were likely biased toward microelectrode recordings from color modules, while those reporting clear shape selectivity were likely biased toward recordings from noncolor modules (Conway and Tsao, 2006; Tanigawa et al., 2010). How does the presence of segregated functional domains imp ...
The visual cortex - Neuroscience Network Basel
... processing of the M- and P- pathways. M - Pathway, Motion analysis: V1 (4B) V2 (Thick stripe) MT (=V5) parietal lobe. = dorsal or parietal pathway. P – Pathway, Form analysis: V1 (4C, Interblob area) V2 (Interstripe) V4 inferior temporal cortex. P – Pathway, Color analysis: V1 (4C), Bl ...
... processing of the M- and P- pathways. M - Pathway, Motion analysis: V1 (4B) V2 (Thick stripe) MT (=V5) parietal lobe. = dorsal or parietal pathway. P – Pathway, Form analysis: V1 (4C, Interblob area) V2 (Interstripe) V4 inferior temporal cortex. P – Pathway, Color analysis: V1 (4C), Bl ...
Local Field Potential in the Visual System
... signals in the visual cortex are of local origin is a subject of current debate. On the one hand, various evidence related to EEG recordings suggests that volume conduction can occur, and electrical signals can be picked up in scalp recordings from sources that are known to be far away from the reco ...
... signals in the visual cortex are of local origin is a subject of current debate. On the one hand, various evidence related to EEG recordings suggests that volume conduction can occur, and electrical signals can be picked up in scalp recordings from sources that are known to be far away from the reco ...
Visual Cortex and Control Processes Stimuli in Opposite Visual
... of three letters presented for 200 ms either unilaterally or bilaterally. Unilateral displays resulted in greater contralateral occipital activations than bilateral displays. This was taken as direct evidence that inter-hemispheric sensory competition can arise between stimuli in opposite visual hem ...
... of three letters presented for 200 ms either unilaterally or bilaterally. Unilateral displays resulted in greater contralateral occipital activations than bilateral displays. This was taken as direct evidence that inter-hemispheric sensory competition can arise between stimuli in opposite visual hem ...
The role of neuronal synchronization in selective attention
... change had occurred. This finding suggests that the processing or the signalling of a sensory change is more efficient when it is handled by an area that is engaged in enhanced gamma-band synchronization [6]. Importantly, the influence of local synchronization of behavioural responses was spatiall ...
... change had occurred. This finding suggests that the processing or the signalling of a sensory change is more efficient when it is handled by an area that is engaged in enhanced gamma-band synchronization [6]. Importantly, the influence of local synchronization of behavioural responses was spatiall ...
Some Analogies Between Visual Cortical and Genetic Maps
... are replicas of an ancient gene for a receptor protein. 31 The genes for the red and green receptor proteins are located adjacent to each other on the X chromosome and have a 96% sequence homology.32 Many individuals have up to three slightly different versions of the gene for the green receptor pro ...
... are replicas of an ancient gene for a receptor protein. 31 The genes for the red and green receptor proteins are located adjacent to each other on the X chromosome and have a 96% sequence homology.32 Many individuals have up to three slightly different versions of the gene for the green receptor pro ...
Visual adaptation: Neural, psychological and computational aspects
... apply to a linear–nonlinear system. Instead, one can make predictions for how filtering properties should change after a change in stimulus statistics in order to maintain coding efficiency. Suppose the parameters of the linear–nonlinear system are optimally suited for encoding a stimulus distribution ...
... apply to a linear–nonlinear system. Instead, one can make predictions for how filtering properties should change after a change in stimulus statistics in order to maintain coding efficiency. Suppose the parameters of the linear–nonlinear system are optimally suited for encoding a stimulus distribution ...
Synchronized Activities among Retinal Ganglion Cells in Response
... checker-board flickering. The results showed that nearby RGCs tended to fire synchronously much more frequently than expected by chance, in response to both stimuli. Under our experimental conditions, synchronous groups could contain three or more cells in response to natural movie; but activities w ...
... checker-board flickering. The results showed that nearby RGCs tended to fire synchronously much more frequently than expected by chance, in response to both stimuli. Under our experimental conditions, synchronous groups could contain three or more cells in response to natural movie; but activities w ...
Visual Properties of Neurons in a Polysensory Area in Superior
... indicates the stimulus location in degrees of visual angle. due to changes in luminance that might ac0” represents the center of gaze; C, contralateral; I, ipsilateral; L, lower; U, upper. company such movement because their movement preference was the same whether The exclusively visual neurons had ...
... indicates the stimulus location in degrees of visual angle. due to changes in luminance that might ac0” represents the center of gaze; C, contralateral; I, ipsilateral; L, lower; U, upper. company such movement because their movement preference was the same whether The exclusively visual neurons had ...
Learning Strengthens the Response of Primary Visual Cortex to
... may have shifted toward the trained stimulus. The observed changes in V1 could be produced locally or could result from feedback from higher cortical areas. Studies of V1 with single-unit recording report different neural effects of learning than those observed here [14–16]. None of the studies repo ...
... may have shifted toward the trained stimulus. The observed changes in V1 could be produced locally or could result from feedback from higher cortical areas. Studies of V1 with single-unit recording report different neural effects of learning than those observed here [14–16]. None of the studies repo ...
The continuous performance test: a window on
... limbic system. The involvement of the limbic system as well as the medial and dorsolateral frontal cortex is seen as resulting from their respective inputs into the association areas, which in turn impact on the inferior parietal lobes to inhibit or facilitate attentional response. The posterior par ...
... limbic system. The involvement of the limbic system as well as the medial and dorsolateral frontal cortex is seen as resulting from their respective inputs into the association areas, which in turn impact on the inferior parietal lobes to inhibit or facilitate attentional response. The posterior par ...
text - Systems Neuroscience Course, MEDS 371, Univ. Conn. Health
... Neurons in V1 project their axons into two pathways that carry different information (Fig. 8). A. V1 neurons that receive information from the P and K pathways form the inferior (ventral) visual pathway that carries information about form (detail), color and depth (distance). V1 neurons in this path ...
... Neurons in V1 project their axons into two pathways that carry different information (Fig. 8). A. V1 neurons that receive information from the P and K pathways form the inferior (ventral) visual pathway that carries information about form (detail), color and depth (distance). V1 neurons in this path ...
KliperEtAl CIP2010
... we used the first 20 principal components of a gray scale representation of the images. The neuronal response for each stimulus was represented as a vector containing in each of its entries the spike rate of one out of multiple stimulus presentations (trials), where the number of trials per stimulus ...
... we used the first 20 principal components of a gray scale representation of the images. The neuronal response for each stimulus was represented as a vector containing in each of its entries the spike rate of one out of multiple stimulus presentations (trials), where the number of trials per stimulus ...
Perception of Motion, Depth, and Form
... N vISIoN,AS IN orHERmental oPerations, we exPerrence the world as a whole. Independent attributesmotion, depth, form, and color-are coordinated into a single visual image. In the two Previous chapters we began to consider how two parallel Pathways-the magnocellular and parvocellular pathways, that e ...
... N vISIoN,AS IN orHERmental oPerations, we exPerrence the world as a whole. Independent attributesmotion, depth, form, and color-are coordinated into a single visual image. In the two Previous chapters we began to consider how two parallel Pathways-the magnocellular and parvocellular pathways, that e ...
KISHORE Aswathy - School of Computing
... According to previous studies (for example, [1], [2]), when perceiving a visual stimulus such as a simple coloured object, the brain stores information about it using what is called a ‘compositional representation’. Accordingly, different features of the object such as shape, texture and colour wil ...
... According to previous studies (for example, [1], [2]), when perceiving a visual stimulus such as a simple coloured object, the brain stores information about it using what is called a ‘compositional representation’. Accordingly, different features of the object such as shape, texture and colour wil ...
Beyond the classical receptive field: The effect of contextual stimuli
... research to experiments in striate and extrastriate cortex, using contextual stimuli, including movie clips and natural scenes. Over the years, theoretical accounts for RF properties have progressively shifted from classic bottom-up processing toward contextual processing with top-down and horizonta ...
... research to experiments in striate and extrastriate cortex, using contextual stimuli, including movie clips and natural scenes. Over the years, theoretical accounts for RF properties have progressively shifted from classic bottom-up processing toward contextual processing with top-down and horizonta ...
Primary Visual Pathway
... of on and off zones • Length cells - respond to length of a bar that was moved across a receptive field • Direction cells - respond to direction of a bar moving across the receptive field. ...
... of on and off zones • Length cells - respond to length of a bar that was moved across a receptive field • Direction cells - respond to direction of a bar moving across the receptive field. ...
T2 - Center for Neural Basis of Cognition
... classical receptive field. Vision is an active process of building representations. ...
... classical receptive field. Vision is an active process of building representations. ...
different sensory modalities
... weaker (fewer impulses, shorter discharge train duration, lower peak frequencies, lower response reliability) than one stimulus alone • Response depression is less common than enhancement; it depends on some specific properties as spatial inhibition, inhibitory surrounds, inhibitory inputs that are ...
... weaker (fewer impulses, shorter discharge train duration, lower peak frequencies, lower response reliability) than one stimulus alone • Response depression is less common than enhancement; it depends on some specific properties as spatial inhibition, inhibitory surrounds, inhibitory inputs that are ...
Visual N1
The visual N1 is a visual evoked potential, a type of event-related electrical potential (ERP), that is produced in the brain and recorded on the scalp. The N1 is so named to reflect the polarity and typical timing of the component. The ""N"" indicates that the polarity of the component is negative with respect to an average mastoid reference. The ""1"" originally indicated that it was the first negative-going component, but it now better indexes the typical peak of this component, which is around 150 to 200 milliseconds post-stimulus. The N1 deflection may be detected at most recording sites, including the occipital, parietal, central, and frontal electrode sites. Although, the visual N1 is widely distributed over the entire scalp, it peaks earlier over frontal than posterior regions of the scalp, suggestive of distinct neural and/or cognitive correlates. The N1 is elicited by visual stimuli, and is part of the visual evoked potential – a series of voltage deflections observed in response to visual onsets, offsets, and changes. Both the right and left hemispheres generate an N1, but the laterality of the N1 depends on whether a stimulus is presented centrally, laterally, or bilaterally. When a stimulus is presented centrally, the N1 is bilateral. When presented laterally, the N1 is larger, earlier, and contralateral to the visual field of the stimulus. When two visual stimuli are presented, one in each visual field, the N1 is bilateral. In the latter case, the N1’s asymmetrical skewedness is modulated by attention. Additionally, its amplitude is influenced by selective attention, and thus it has been used to study a variety of attentional processes.