Visual selective attention in amnestic mild cognitive impairment

Abstract

Objectives: Subtle deficits in visual selective attention have been found in amnestic mild cognitive impairment (aMCI). However, few studies have explored performance on visual search paradigms or the Simon task, which are known to be sensitive to disease severity in Alzheimer's patients. Furthermore, there is limited research investigating how deficiencies can be ameliorated with exogenous support (auditory cues).

Method: Sixteen individuals with aMCI and 14 control participants completed 3 experimental tasks that varied in demand and cue availability: visual search-alerting, visual search-orienting, and Simon task.

Results: Visual selective attention was influenced by aMCI, auditory cues, and task characteristics. Visual search abilities were relatively consistent across groups. The aMCI participants were impaired on the Simon task when working memory was required, but conflict resolution was similar to controls. Spatially informative orienting cues improved response times, whereas spatially neutral alerting cues did not influence performance. Finally, spatially informative auditory cues benefited the aMCI group more than controls in the visual search task, specifically at the largest array size where orienting demands were greatest.

Discussion: These findings suggest that individuals with aMCI have working memory deficits and subtle deficiencies in orienting attention and rely on exogenous information to guide attention.

Keywords: Cues; Mild cognitive impairment; Selective attention; Working memory..