Psychophysical Studies of Visual Cortical Functions

Abstract

Our research continues to study two primary areas. First is the area of visual attention where we have shown that there are both transient and sustained components. In contrast to the sustained component, we find that the transient component is much more powerful, is short lasting, is relatively independent of volition and finally, is also independent of the stimulus that elicits it. Thus, it is a genuine 'attentional' effect not tied directly to the sensory stimulus but is probably operative relatively early in visual cortical processing, particularly in relation to the sustained component. We have also shown that the latency of this transient component is reduced by the prior removal of a stimulus fixation mark. Such a finding provides strong support for the view that express saccadic eye movements (seen under similar conditions) are mediated by rapid shifts of attention. Second, we have been studying issues related to partial visibility. In particular, we examine how the visual system deals with occlusion. Our results indicate that the occlusive relations of surfaces have widespread effects in vision, influencing color, motion, transparency and depth.

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Document Details

Document Type
Technical Report
Publication Date
Oct 20, 1988
Accession Number
ADA202814

Entities

People

  • Ken Nakayama

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  • Biomedical

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  • Abstracts
  • Artificial Intelligence
  • Availability
  • Classification
  • Cognitive Science
  • Computer Vision
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  • Eye
  • Image Segmentation
  • Mental Processes
  • Ophthalmology
  • Perception
  • Psychological Phenomena And Processes
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Fields of Study

  • Biology

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  • Neuroscience
  • Theoretical Analysis.
  • Vision Science/Vision Psychology/Cognitive Neuroscience.