Prime-sight in a blindsight subject.
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.
Weiskrantz
Lawrence
L
Department of Experimental Psychology, University of Oxford, South Parks Road, Oxford, OX1 3UD, UK. larry.weiskrantz@psy.ox.ac.uk
Cowey
Alan
A
Hodinott-Hill
Iona
I
D000328:Adult; D000360:Afterimage; D019575:Blindness, Cortical / Q000503:physiopathology*; D006801:Humans; D010775:Photic Stimulation; D011184:Postoperative Period; D014793:Visual Cortex / Q000601:surgery