Prime-sight in a blindsight subject

Nat Neurosci. 2002 Feb;5(2):101-2. doi: 10.1038/nn793.

Abstract

A subject (D.B.) who had no experience of visual stimuli in a field defect caused by visual cortex damage but could discriminate them ('blindsight') nevertheless reported visible after-images of the stimuli when they were turned off ('prime-sight'). This was investigated using projected visual stimuli of varying colors, contrasts, shapes and spatial frequencies, and by measuring the properties of the after-images, including their duration, size scaling, color and interocular transfer, comparing the capacity of the blindsight and prime-sight modes. These phenomena offer a unique opportunity to compare conscious and unconscious neural events in response to the same visual events.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Afterimage*
  • Blindness, Cortical / physiopathology*
  • Humans
  • Photic Stimulation
  • Postoperative Period
  • Visual Cortex / surgery