Frontal Lobe Functions in Normal Aging: Metacognition, Autonomy, and Quality of Life

Starting from the "frontal lobe hypothesis of cognitive aging", we aim to study the metacognitive functions (deception, reciprocity, cognitive and affective theory of mind), autonomy and quality of life in normal aging.

Eighty healthy subjects (30 young adults [YA] aged 20-40, 30 old adults [OA] aged 65-79 and 20 very old adults [VOA] aged 80 and over) participated in our study. Standard and novel neuropsychological tasks have been used, assessing abilities to understand others' mental and affective states, deceptive and cooperative situations.

OA and VOA's performances are significantly poorer than those of YA on first-/second-order false beliefs, deception, reciprocity and emotion recognition tasks. VOA have made more errors than other participants on control false beliefs, general cognition, and memory tasks. Normal aging seems also to be characterized by a reduction in processing speed. The level of instrumental activities of daily living decreases with aging. Theory of mind is associated with individual general cognitive state and executive functions, but not with OA and VOA's levels of autonomy and quality of life.

In this study, we have shown an age-related deterioration of metacognitive functions, which does not seem to be associated with old adults' autonomy and satisfaction of life. A good level of mental activity could be necessary to maintain satisfactory interpersonal relationships.