Cat and mouse search: the influence of scene and object analysis on eye movements when targets change locations during search.

We explored the influence of early scene analysis and visible object characteristics on eye movements when searching for objects in photographs of scenes. On each trial, participants were shown sequentially either a scene preview or a uniform grey screen (250 ms), a visual mask, the name of the target and the scene, now including the target at a likely location. During the participant's first saccade during search, the target location was changed to: (i) a different likely location, (ii) an unlikely but possible location or (iii) a very implausible location. The results showed that the first saccade landed more often on the likely location in which the target re-appeared than on unlikely or implausible locations, and overall the first saccade landed nearer the first target location with a preview than without. Hence, rapid scene analysis influenced initial eye movement planning, but availability of the target rapidly modified that plan. After the target moved, it was found more quickly when it appeared in a likely location than when it appeared in an unlikely or implausible location. The findings show that both scene gist and object properties are extracted rapidly, and are used in conjunction to guide saccadic eye movements during visual search.This article is part of the themed issue 'Auditory and visual scene analysis'.

Evidence of criterion validity for the Benton Visual Retention Test: comparison between older adults with and without a possible diagnosis of Alzheimer's disease

The present study sought to provide evidence of criterion validity for the Benton Visual Retention Test by making comparisons between older adults with and without a possible diagnosis of Alzheimer's disease. The control group was composed of 50 older adults, and the clinical group was composed by 16 subjects. Descriptive and inferential statistics were performed, including χ² test, F and Wald statistics, t-test, analyses of covariance with α = .05, and effect size calculations. We used a sociodemographic data form, the Geriatric Depression Scale-15, and Mini Mental State Examination. Despite the small clinical sample size, the results pointed to evidence of validity for the Benton Visual Retention Test for Administration A (Memory) and Administration C (Copy). The clinical group had significantly poorer performance on most scores. These results also indicate important deficits in other neuropsychological functions in Alzheimer's disease...