Lec 55 Cerebral Cortical Integration Flashcards
What are the two segregated systems of cognition in V1?
Where stream = occipital
What stream = occipital temporal
What is purpose of the where stream of V1?
process motion and spatial relationships
What is prosopagnosia? is it due to problem with “where” or “what”?
- visual agnosia for faces = inability to recognize previously known human faces or learn new ones
damage to “what” = occipito-temporal region [fusiform gyrus]
What is visual object agnosia? is it due to problem with “where” or “what”?
- inability to reognize generic classes of objects
damage to “what” = occipito-temporal
What is balint’ssyndrome? is it due to problem with “where” or “what”?
3 major components:
- optic ataxia [can’t point at something based on visual cue]
- ocular ataxia [can’t shift gaze at will toward new visual stimulus]
- simultanagnosia [perception of only parts of visual field, can’t perceive two things at once]
damage to “where” = bilateral damage to occipito-parietal
What are functions of prefrontal cortex?
- working memory
- planning
- executive function
- top-down cognitive control [rule forming]
- response inhibition
What impairments associated with PFC damage?
- working memory deficit
- impaired decision making
- difficulty attending to task
- problem solving deficits
- poor planning
- impaired executive function
- perseveration
- impulsivity/disinhibition
What are characteristics of neurons that are active during delay period in monkey test? Where are they?
- active during delay
- spatially selective
- resistant to distraction
in prefrontal cortex
What is path of activation in delay task with visual stimulus and response?
- visual stimulus of face: activity in visual cortex durign cue
- during delay, inferio temporal [what] and PFC activate
- /4 late delay: moves PFC to premotor, still active in inferior temporal
- during choice: motor cortex activates too
