Document Detail


Can blindsight be superior to 'sighted-sight'?
MedLine Citation:
PMID:  16764848     Owner:  NLM     Status:  MEDLINE    
Abstract/OtherAbstract:
DB, the first blindsight case to be tested extensively (Weiskrantz, 1986) has demonstrated the ability to detect and discriminate a range of visual stimuli presented within his perimetrically blind visual field defect. In a temporal two alternative forced choice (2AFC) detection experiment we have investigated the limits of DB's detection ability within his field defect. Blind field performance was compared to his sighted field performance and to an age-matched control group (n=6). DB reliably detected the presence of a small (2 degrees ), low contrast (7%), 4.6c/ degrees Gabor patch with the same space-averaged luminance as the background presented within his blind field but performed at chance levels at the same eccentricity (11.3 degrees ) within his sighted field. Investigation of detection as a function of stimulus contrast revealed DB's ability to detect the presence of an 8% contrast stimulus within his blind field, compared to 12% in his sighted field. No significant difference in detection performance between DB's sighted field and the performance of six age-matched control participants suggests poor sighted field performance does not account for the results. Monocular testing also rules out differences between the eyes as an explanation, suggesting that DB demonstrates superior detection for certain stimuli within his visual field defect compared to normal vision.
Authors:
Ceri T Trevethan; Arash Sahraie; Larry Weiskrantz
Related Documents :
6957888 - Visual evoked potentials: evidence for lateral interactions.
18691218 - Sensory ocular dominance based on resolution acuity, contrast sensitivity and alignment...
12705958 - Motion sharpening and contrast: gain control precedes compressive non-linearity?
12074948 - Interactions between chromatic- and luminance-contrast-sensitive stereopsis mechanisms.
14514218 - Evaluation of an auditory model for echo delay accuracy in wideband biosonar.
2708678 - Effects of acoustic overstimulation on spectral and temporal processing in the amphibia...
Publication Detail:
Type:  Journal Article; Research Support, Non-U.S. Gov't     Date:  2006-06-09
Journal Detail:
Title:  Cognition     Volume:  103     ISSN:  0010-0277     ISO Abbreviation:  Cognition     Publication Date:  2007 Jun 
Date Detail:
Created Date:  2007-04-09     Completed Date:  2007-06-01     Revised Date:  2008-11-21    
Medline Journal Info:
Nlm Unique ID:  0367541     Medline TA:  Cognition     Country:  Netherlands    
Other Details:
Languages:  eng     Pagination:  491-501     Citation Subset:  IM    
Affiliation:
Vision Research Laboratories, School of Psychology, University of Aberdeen, Aberdeen, Scotland, UK. c.trevethan@abdn.ac.uk
Export Citation:
APA/MLA Format     Download EndNote     Download BibTex
MeSH Terms
Descriptor/Qualifier:
Choice Behavior
Contrast Sensitivity
Humans
Middle Aged
Signal Detection, Psychological*
Visual Fields
Visual Perception*

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine


Previous Document:  Tangled webs: tracing the connections between genes and cognition.
Next Document:  A Bayesian view of covariation assessment.