Evidence that the Visual Cortex is Necessary for Awareness

• If the cortex is removed, patient report blindness (Weiskrantz et al., 1974)

  

  • If secondary visual cortex is removed towards temporal lobe: agnosia (Luria, 1973)

  

  • Patients can see but not make sense of what they see
  • draw disjointed representations

  • If parietal cortex damaged on right, get hemispatial neglect (Luria, 1973)

  

  • Not respond to stimuli on left
  • Draw mostly right half of figure
  • Extinction experiments indicate awareness is suppressed but possible

  

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