Scene categorization in Alzheimer's disease: a saccadic choice task

Dement Geriatr Cogn Dis Extra. 2015 Jan 16;5(1):1-12. doi: 10.1159/000366054. eCollection 2015 Jan-Apr.

Abstract

Aims: We investigated the performance in scene categorization of patients with Alzheimer's disease (AD) using a saccadic choice task.

Method: 24 patients with mild AD, 28 age-matched controls and 26 young people participated in the study. The participants were presented pairs of coloured photographs and were asked to make a saccadic eye movement to the picture corresponding to the target scene (natural vs. urban, indoor vs. outdoor).

Results: The patients' performance did not differ from chance for natural scenes. Differences between young and older controls and patients with AD were found in accuracy but not saccadic latency.

Conclusions: The results are interpreted in terms of cerebral reorganization in the prefrontal and temporo-occipital cortex of patients with AD, but also in terms of impaired processing of visual global properties of scenes.

Keywords: Aging; Alzheimer's disease; Eye movements; Saccade; Scene perception; Vision.