Journal
VISION RESEARCH
Volume 42, Issue 8, Pages 949-967Publisher
PERGAMON-ELSEVIER SCIENCE LTD
DOI: 10.1016/S0042-6989(02)00039-1
Keywords
transient covert attention; discrimination; spatial frequency; performance fields; asymmetry
Categories
Funding
- NEI NIH HHS [EY07027] Funding Source: Medline
Ask authors/readers for more resources
We examined the effect of transient covert attention on the psychometric function for contrast sensitivity in an orientation discrimination task when the target was presented alone in the absence of distracters and visual masks. Transient covert attention decreased both the threshold (consistent with a contrast gain mechanism) and, less consistently, the slope of the psychometric function. We assessed performance at 8 equidistant locations (4.5degrees eccentricity) and found that threshold and slope depended on target location-both were higher on the vertical than the horizontal meridian, particularly directly abode fixation. All effects were robust across a range of spatial frequencies, and the Visual field asymmetries increased with spatial frequency. Notwithstanding the dependence of the psychometric function on target location. attention improved performance to a similar extent across the visual field. Given that. in this study, we excluded all sources of external noise, and that we showed experimentally that spatial uncertainty cannot explain the present results, we conclude that the observed attentional benefit is consistent with signal enhancement. (C) 2002 Elsevier Science Ltd. All rights reserved.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available