Effects of Unseen Stimuli on Reaction Times to Seen Stimuli in Monkeys with Blindsight

Authors: Cowey A.¹; Stoerig P.²; Le Mare C.¹

Source: Consciousness and Cognition, Volume 7, Number 3, September 1998 , pp. 312-323(12)

Buy & download fulltext article:

Price: $52.63 plus tax (Refund Policy)

Abstract:

In three macaque monkeys with unilateral removal of primary visual cortex and in one unoperated monkey, we measured reaction times to a visual target that was presented at a lateral eccentricity of 20° in the normal, left, visual hemifield. When an additional stimulus was presented at the corresponding position in the right hemifield (hemianopic in three of the monkeys), it significantly slowed the reaction time to the left target if it preceded it by delays from 100–500 msec. The most effective delay depended on the particular experimental paradigm and perhaps on the experience of the monkey with the task. The results show that reaction times to seen targets in the normal hemifield of monkeys are influenced by the presentation of “unseen” targets in the anopic hemifield, as in some patients with cortically blind visual field defects. Copyright 1998 Academic Press.

Language: English

Document Type: Research article

Affiliations: 1: University of Oxford, Department of Experimental Psychology, South Parks Road, Oxford, OX1 3UD, UK 2: Heinrich-Heine-Universität, Inst. Physiol. Psychology, Universitätsstr 1, Bldg 23.03, Düsseldorf, 40225, Germany

Publication date: 1998-09-01