Age-related cortical changes and cognitive performance in healthy adults

Aging is a continuous process with cortical thinning as a common consequence. This study aimed to evaluate cortical thickness, volume and area differences associated with age in healthy population. Seventy-six healthy individuals were divided into three age groups: younger (25-40 years, n = 25), middle-aged (41-55 years, n = 24), and older (56-80 years, n = 27). The elderly group exhibited significantly reduced cortical gray matter in frontal regions (left rostral middle frontal, bilateral lateral orbitofrontal, precentral gyri), temporal (middle temporal, right superior temporal, right inferior temporal), limbic regions (left insula, left posterior cingulate gyrus), occipital (right cuneus, lateral occipital, right lateral occipital), and parietal (precuneus and left postcentral gyri) compared to the younger group. Older adults exhibited age-related decline in performance of auditory verbal learning (AVL) and recall memory, working memory, visuo-motor coordination, compared to younger adults. Thinning of the left posterior cingulate gyrus is positively correlated with auditory verbal learning performance in middle and older age groups. Total and bilateral cortical thickness and volumes were found to be negatively correlated with age. The present study shows the impact of aging on cortical thickness, volume and cognitive performance and have implications in the management of cognitive decline in the ageing population including prophylactic interventions thereof.