primary visual cortex and visual awareness
... rather than hard-wired. Perhaps the information represented in V1 is necessary only for certain types of awareness (such as figure–ground segmentation, perception during focal attention, perception of low-level features and so on). Some theories consider consciousness in terms of a dynamic, global n ...
... rather than hard-wired. Perhaps the information represented in V1 is necessary only for certain types of awareness (such as figure–ground segmentation, perception during focal attention, perception of low-level features and so on). Some theories consider consciousness in terms of a dynamic, global n ...
When the Sun Prickles Your Nose: An EEG Study Identifying
... Background: Exposure to bright light such as sunlight elicits a sneeze or prickling sensation in about one of every four individuals. This study presents the first scientific examination of this phenomenon, called ‘the photic sneeze reflex’. Methodology and Principal Findings: In the present experim ...
... Background: Exposure to bright light such as sunlight elicits a sneeze or prickling sensation in about one of every four individuals. This study presents the first scientific examination of this phenomenon, called ‘the photic sneeze reflex’. Methodology and Principal Findings: In the present experim ...
Recounting the impact of Hubel and Wiesel
... and Wiesel’s first paper (1959) can be appreciated. Their introduction set the tone: ‘In the central nervous system the visual pathway from retina to striate cortex provides an opportunity to observe and compare single unit responses at several distinct levels. Patterns of light stimuli most effecti ...
... and Wiesel’s first paper (1959) can be appreciated. Their introduction set the tone: ‘In the central nervous system the visual pathway from retina to striate cortex provides an opportunity to observe and compare single unit responses at several distinct levels. Patterns of light stimuli most effecti ...
Superior Colliculus and Visual Spatial Attention
... 2004, Fecteau et al. 2004). These results support the view that activity in the SC reflects both the stimulus-driven and top-down factors that regulate spatial attention and saccade selection (Fecteau & Munoz 2006). Although SC activity may have been restricted to spatial attention associated with ey ...
... 2004, Fecteau et al. 2004). These results support the view that activity in the SC reflects both the stimulus-driven and top-down factors that regulate spatial attention and saccade selection (Fecteau & Munoz 2006). Although SC activity may have been restricted to spatial attention associated with ey ...
Visual Response Properties of Neurons in Four Extrastriate Visual
... Usually, two or three extrastriate areas were studied in an animal. Most units could be unambiguously assigned to a particular area. However, some units (126/480) were recorded at area boundaries or near uncertain area boundaries, and these were excluded from the data analyses reported here. Assignm ...
... Usually, two or three extrastriate areas were studied in an animal. Most units could be unambiguously assigned to a particular area. However, some units (126/480) were recorded at area boundaries or near uncertain area boundaries, and these were excluded from the data analyses reported here. Assignm ...
Visual Cortex and Control Processes Stimuli in Opposite Visual
... particular target side against bilateral target-with-distractor trials for that target side. This was done separately for each target side to examine any impact of inter-hemifield distractor competition on the occipital response contralateral to each target. In this way, we could take advantage of t ...
... particular target side against bilateral target-with-distractor trials for that target side. This was done separately for each target side to examine any impact of inter-hemifield distractor competition on the occipital response contralateral to each target. In this way, we could take advantage of t ...
Attention as a decision in information space
... decisions need not be expressed in LIP, suggesting that this area ‘‘reads out’’ decision computations only in variable, task-specific manner. In a subsequent series of experiments we asked whether, in addition to responding to salient visual stimuli, LIP is also important for effortful, top-down att ...
... decisions need not be expressed in LIP, suggesting that this area ‘‘reads out’’ decision computations only in variable, task-specific manner. In a subsequent series of experiments we asked whether, in addition to responding to salient visual stimuli, LIP is also important for effortful, top-down att ...
Brainstem Auditory Evoked Potentials
... or mastoid) positions record voltage differences generated by stimulation of auditory pathways, using Cz (vertex) as a common reference. Waveforms are recorded from ipsilateral and contralateral pathways simultaneously, allowing easier recognition of individual peaks. Lowand high-frequency filters a ...
... or mastoid) positions record voltage differences generated by stimulation of auditory pathways, using Cz (vertex) as a common reference. Waveforms are recorded from ipsilateral and contralateral pathways simultaneously, allowing easier recognition of individual peaks. Lowand high-frequency filters a ...
Neuronal Interaction Dynamics in Cat Primary Visual Cortex
... matches the typical RF sizes found in area 17 of the cat (Orban, 1984). The vertical arrow indicates the spatial extension in terms of visual field coordinates. B, Population representations of the elementary stimuli computed as two-dimensional DPAs over visual space after Gaussian interpolation (co ...
... matches the typical RF sizes found in area 17 of the cat (Orban, 1984). The vertical arrow indicates the spatial extension in terms of visual field coordinates. B, Population representations of the elementary stimuli computed as two-dimensional DPAs over visual space after Gaussian interpolation (co ...
Large-Field Visual Motion Directly Induces an Involuntary Rapid
... Recent neuroscience studies have been concerned with how aimed movements are generated on the basis of target localization. However, visual information from the surroundings as well as from the target can influence arm motor control, in a manner similar to known effects in postural and ocular motor ...
... Recent neuroscience studies have been concerned with how aimed movements are generated on the basis of target localization. However, visual information from the surroundings as well as from the target can influence arm motor control, in a manner similar to known effects in postural and ocular motor ...
Magnetoencephalographic Investigation of Human Cortical Area V1
... psychophysical studies demonstrating a contribution from color-opponent mechanisms to motion perception (e.g., Cavanagh and Anstis, 1991). Some studies suggest that there may be more than one chromatic motion system (Derrington and Henning, 1993; Gorea et al., 1993a,b; Cropper and Derrington, 1994; ...
... psychophysical studies demonstrating a contribution from color-opponent mechanisms to motion perception (e.g., Cavanagh and Anstis, 1991). Some studies suggest that there may be more than one chromatic motion system (Derrington and Henning, 1993; Gorea et al., 1993a,b; Cropper and Derrington, 1994; ...
Saccadic Suppression of Retinotopically Localized Blood Oxygen
... retina and is, therefore, physically identical to that presented when no saccadic programming is in course. In this functional magnetic resonance imaging event-related study, we flashed Gabor patches at different times before the onset of a horizontal saccade and measured blood oxygen level-dependen ...
... retina and is, therefore, physically identical to that presented when no saccadic programming is in course. In this functional magnetic resonance imaging event-related study, we flashed Gabor patches at different times before the onset of a horizontal saccade and measured blood oxygen level-dependen ...
A simultaneous ERP/fMRI investigation of the P300 aging effect
... al., 2008; Solbakk et al., 2008). Because elderly participants are typically found to perform the oddball task at a comparable level with younger participants, the differences in P300 topography have been proposed to represent the compensatory activation of additional neural networks. Fabiani et al. ...
... al., 2008; Solbakk et al., 2008). Because elderly participants are typically found to perform the oddball task at a comparable level with younger participants, the differences in P300 topography have been proposed to represent the compensatory activation of additional neural networks. Fabiani et al. ...
The Constructive Nature of Visual Processing
... An important step in object recognition is separating figure from background. At different moments the same elements in the visual field can be organized into a recognizable figure or serve as part of the background for other figures (Figure 25–2). Segmentation relies not only on certain geometric p ...
... An important step in object recognition is separating figure from background. At different moments the same elements in the visual field can be organized into a recognizable figure or serve as part of the background for other figures (Figure 25–2). Segmentation relies not only on certain geometric p ...
Different Stimuli, Different Spatial Codes: A Visual Map and an
... periphery. This coding format discrepancy therefore poses a potential problem for brain regions responsible for representing both visual and auditory information. Here, we investigated the coding of auditory space in the primate superior colliculus(SC), a structure known to contain visual and oculom ...
... periphery. This coding format discrepancy therefore poses a potential problem for brain regions responsible for representing both visual and auditory information. Here, we investigated the coding of auditory space in the primate superior colliculus(SC), a structure known to contain visual and oculom ...
Genardi Brodmann-Detail
... According to functional neuroimaging techniques BA4 participates in three different groups of functions: Motor, somatosensory, and “others” (“verbal encoding during a non-semantic process”, “attention to action”, and “motor memory for visual landmarks”). Motor function is the traditional function, a ...
... According to functional neuroimaging techniques BA4 participates in three different groups of functions: Motor, somatosensory, and “others” (“verbal encoding during a non-semantic process”, “attention to action”, and “motor memory for visual landmarks”). Motor function is the traditional function, a ...
Brodmann-Detail
... According to functional neuroimaging techniques BA4 participates in three different groups of functions: Motor, somatosensory, and “others” (“verbal encoding during a non-semantic process”, “attention to action”, and “motor memory for visual landmarks”). Motor function is the traditional function, a ...
... According to functional neuroimaging techniques BA4 participates in three different groups of functions: Motor, somatosensory, and “others” (“verbal encoding during a non-semantic process”, “attention to action”, and “motor memory for visual landmarks”). Motor function is the traditional function, a ...
directory of functions - Stress Therapy Solutions
... According to functional neuroimaging techniques BA4 participates in three different groups of functions: Motor, somatosensory, and “others” (“verbal encoding during a non-semantic process”, “attention to action”, and “motor memory for visual landmarks”). Motor function is the traditional function, a ...
... According to functional neuroimaging techniques BA4 participates in three different groups of functions: Motor, somatosensory, and “others” (“verbal encoding during a non-semantic process”, “attention to action”, and “motor memory for visual landmarks”). Motor function is the traditional function, a ...
neural mechanisms for detecting and remembering novel events
... contributes to both adaptation and repetition suppression. An intracellular recording study identified a calcium-dependent potassium current as an important contributor to adaptation in the primary visual cortex17. The same current was identified as a plausible mechanism for repetition suppression i ...
... contributes to both adaptation and repetition suppression. An intracellular recording study identified a calcium-dependent potassium current as an important contributor to adaptation in the primary visual cortex17. The same current was identified as a plausible mechanism for repetition suppression i ...
Integration of Visual and Auditory Information by Superior Temporal
... Journal of Cognitive Neuroscience 17:3, pp. 377–391 ...
... Journal of Cognitive Neuroscience 17:3, pp. 377–391 ...
Hemispheric Asymmetry in Visual Perception Arises from Differential Encoding
... hidden unit has 7 connections to the input layer. This parameter combination is the point where the overall error starts to converge and the two networks have a comparable performance level. A Gaussian probability density function (PDF) is used to determine the probability of having a connection bet ...
... hidden unit has 7 connections to the input layer. This parameter combination is the point where the overall error starts to converge and the two networks have a comparable performance level. A Gaussian probability density function (PDF) is used to determine the probability of having a connection bet ...
different sensory modalities
... effective sensory stimulus activates many of the same neurons, enhancing its salience Visual-multisensory and somatosensory-multisensory neurons are not clustered in one region of the superior colliculus representing one region of visual or somatosensory space: they cover the entire structure, so th ...
... effective sensory stimulus activates many of the same neurons, enhancing its salience Visual-multisensory and somatosensory-multisensory neurons are not clustered in one region of the superior colliculus representing one region of visual or somatosensory space: they cover the entire structure, so th ...
Repetition and the brain: neural models of stimulus
... potentials (LFPs) caused by transmembrane currents in large numbers of neurons. Most EEG studies examine event-related potentials (ERPs), which reflect changes in electrical potential during the few hundred milliseconds following stimulus onset, averaged across trials. The earliest object repetition ...
... potentials (LFPs) caused by transmembrane currents in large numbers of neurons. Most EEG studies examine event-related potentials (ERPs), which reflect changes in electrical potential during the few hundred milliseconds following stimulus onset, averaged across trials. The earliest object repetition ...
Repetition and the brain: neural models of stimulus
... potentials (LFPs) caused by transmembrane currents in large numbers of neurons. Most EEG studies examine event-related potentials (ERPs), which reflect changes in electrical potential during the few hundred milliseconds following stimulus onset, averaged across trials. The earliest object repetition ...
... potentials (LFPs) caused by transmembrane currents in large numbers of neurons. Most EEG studies examine event-related potentials (ERPs), which reflect changes in electrical potential during the few hundred milliseconds following stimulus onset, averaged across trials. The earliest object repetition ...
Top-Down Versus Bottom-Up Control of Attention in the Prefrontal
... perisaccadic period, beginning 150 ms before saccade to 50 ms afterward) and compared to a baseline, an intertrial interval (ITI) epoch (a 200-ms window starting 500 ms before trial onset). Shaded regions are 95% confidence intervals around average coherence. Frequencies below 10 Hz are not meaningf ...
... perisaccadic period, beginning 150 ms before saccade to 50 ms afterward) and compared to a baseline, an intertrial interval (ITI) epoch (a 200-ms window starting 500 ms before trial onset). Shaded regions are 95% confidence intervals around average coherence. Frequencies below 10 Hz are not meaningf ...
P200
In neuroscience, the visual P200 or P2 is a waveform component or feature of the event-related potential (ERP) measured at the human scalp. Like other potential changes measurable from the scalp, this effect is believed to reflect the post-synaptic activity of a specific neural process. The P2 component, also known as the P200, is so named because it is a positive going electrical potential that peaks at about 200 milliseconds (varying between about 150 and 275 ms) after the onset of some external stimulus . The distribution of this component in the brain, as measured by electrodes placed across the scalp, is located around the centro-frontal and the parieto-occipital region. It is generally found to be maximal around the vertex (frontal region) of the scalp, however there have been some topographical differences noted in ERP studies of the P2 in different experimental conditions.Research on the visual P2 is at an early stage compared to other more established ERP components and there is much that we still do not know about it. Part of the difficulty of clearly characterizing this component is that it appears to be modulated by a large and diverse number of cognitive tasks. Functionally, there seems to be partial agreement amongst researchers in the field of cognitive neuroscience that the P2 represents some aspect of higher-order perceptual processing, modulated by attention. It is known that the P2 is typically elicited as part of the normal response to visual stimuli and has been studied in relation to visual search and attention, language context information, and memory and repetition effects. The amplitude of the peak of the waveform may be modulated by many different aspects of visual stimuli, which allow it to be used for studies of visual cognition and disease. In general, the P2 may be a part of cognitive matching system that compares sensory inputs with stored memory.