NASA Logo

NTRS

NTRS - NASA Technical Reports Server

Back to Results
Stimulus information contaminates summation tests of independent neural representations of featuresMany models of visual processing assume that visual information is analyzed into separable and independent neural codes, or features. A common psychophysical test of independent features is known as a summation study, which measures performance in a detection, discrimination, or visual search task as the number of proposed features increases. Improvement in human performance with increasing number of available features is typically attributed to the summation, or combination, of information across independent neural coding of the features. In many instances, however, increasing the number of available features also increases the stimulus information in the task, as assessed by an optimal observer that does not include the independent neural codes. In a visual search task with spatial frequency and orientation as the component features, a particular set of stimuli were chosen so that all searches had equivalent stimulus information, regardless of the number of features. In this case, human performance did not improve with increasing number of features, implying that the improvement observed with additional features may be due to stimulus information and not the combination across independent features.
Document ID
20040087754
Acquisition Source
Legacy CDMS
Document Type
Reprint (Version printed in journal)
Authors
Shimozaki, Steven S.
(University of California Santa Barbara, CA, United States)
Eckstein, Miguel P.
Abbey, Craig K.
Date Acquired
August 21, 2013
Publication Date
January 1, 2002
Publication Information
Publication: Journal of vision (Charlottesville, Va.)
Volume: 2
Issue: 5
Subject Category
Life Sciences (General)
Funding Number(s)
CONTRACT_GRANT: 53455
Distribution Limits
Public
Copyright
Other
Keywords
NASA Discipline Space Human Factors
Non-NASA Center
NASA Program Biomedical Research and Countermeasures

Available Downloads

There are no available downloads for this record.
No Preview Available