One critical component of normal visual behavior is the ability to find a target stimulus in a visual field containing multiple distracting stimuli. The proposed experiments fall into two groups. One examines what attributes of the stimulus are critical for efficient search, and the other asks where in the visual field those attributes can be processed. Search for almost any stimulus is harder in the periphery. These changes in performance with eccentricity are not fully explained by the well-studied decreases in acuity and sensitivity with eccentricity. The investigator plans to investigate what underlies the substantial eccentricity effects in visual search and explain the impact of visual and non-visual stress on such mechanisms. These """"""""Useful Field of View"""""""" effects are known to be more marked in older Ss and have been shown to correlate with driving accidents. The investigator plans to simulate several natural visual stressors to examine their impact on the Useful Field of View. The second, what, aspect of the project is concerned with the relationship of search performance to the properties of the stimuli. Visual search is poised at a bottleneck in visual processing. Early stages of processing are largely parallel with all stimuli processed at once. In later stages, only a restricted region can be processed at one time. The parallel stage has been thought to be limited to the processing of a few basic features. However, recent data leads to the conclusion that parallel processes relatively early in the visual pathway accomplish a division of the stimulus into potential search items or objects. The PI plans to investigate the existence of an """"""""item map"""""""" in the parallel stages of visual processing. This research will expand our understanding of those behaviors, from driving to radiology, that require visual search.

Agency
National Institute of Health (NIH)
Institute
National Eye Institute (NEI)
Type
Research Project (R01)
Project #
5R01EY005087-15
Application #
2710865
Study Section
Visual Sciences B Study Section (VISB)
Project Start
1991-08-01
Project End
1999-07-31
Budget Start
1998-08-01
Budget End
1999-07-31
Support Year
15
Fiscal Year
1998
Total Cost
Indirect Cost
Name
Brigham and Women's Hospital
Department
Type
DUNS #
071723621
City
Boston
State
MA
Country
United States
Zip Code
02115
Palmer, Evan M; Horowitz, Todd S; Torralba, Antonio et al. (2011) What are the shapes of response time distributions in visual search? J Exp Psychol Hum Percept Perform 37:58-71
Wolfe, Jeremy M; Palmer, Evan M; Horowitz, Todd S (2010) Reaction time distributions constrain models of visual search. Vision Res 50:1304-11
Wolfe, Jeremy M; Reijnen, Ester; Van Wert, Michael J et al. (2009) In visual search, guidance by surface type is different than classic guidance. Vision Res 49:765-73
Wolfe, Jeremy M; Horowitz, Todd S; Van Wert, Michael J et al. (2007) Low target prevalence is a stubborn source of errors in visual search tasks. J Exp Psychol Gen 136:623-38
Wolfe, Jeremy M; Horowitz, Todd S; Michod, Kristin O (2007) Is visual attention required for robust picture memory? Vision Res 47:955-64
Wolfe, J M; Klempen, N; Dahlen, K (2000) Postattentive vision. J Exp Psychol Hum Percept Perform 26:693-716
Wolfe, J M; Bennett, S C (1997) Preattentive object files: shapeless bundles of basic features. Vision Res 37:25-43
Wolfe, J M (1995) The pertinence of research on visual search to radiologic practice. Acad Radiol 2:74-8
Bilsky, A B; Wolfe, J M (1995) Part-whole information is useful in visual search for size x size but not orientation x orientation conjunctions. Percept Psychophys 57:749-60
Wolfe, J M; Friedman-Hill, S R; Bilsky, A B (1994) Parallel processing of part-whole information in visual search tasks. Percept Psychophys 55:537-50