Neural correlates of focused attention in cognitively normal older adults

摘要

Focused attention (FA) is among the cognitive functions that decline with aging. The Stroop task was used to investigate the neural correlates underlying FA in cognitively normal older adults. Twenty-one participants underwent a novel functional magnetic resonance imaging (fMRI) verbal Stroop task paradigm. Colour words were printed in an incongruent ink colour. Series 1 consisted of four blocks “Read the word” followed by four blocks “Say the colour of the ink”;Series 2 alternated between the two conditions. Functional data were analyzed using SPM5 to detect anatomical areas with significant signal intensity differences between the conditions. Within-group analyses of the “Say the colour of the ink” minus “Read the word” contrast yielded significant activation in the left supplementary motor area, bilateral inferior frontal gyrus, bilateral precentral gyrus, left insula and right superior frontal gyrus (p < 0.05, uncorrected). These results, using verbal responses, are consistent with previous manual modality Stroop-fMRI studies in older adults. Verbal responses may provide a more suitable modality for older adults and certain patient populations.