Identifying the neural mechanisms associated with older adults' dynamic theory of mind judgments during a movie-watching task.

Aging is associated with widespread deficits in theory of mind - the ability to infer others' mental and emotional states. Theory of mind is a complex construct, but age deficits are generally measured in a single domain, overlooking how older adults engage multiple theory of mind processes concurrently and spontaneously. The current work used neuroimaging to characterize the neural mechanisms associated with older adults' deficits in concurrent theory of mind judgments (awkwardness, deception) during a movie-watching task. 102 older adults (MAge = 73.5, SD = 6.6) and 110 young adults (MAge = 21.75, SD = 4.2) passively viewed a mockumentary television show while undergoing functional magnetic resonance imaging. Continuous ratings of awkwardness and deception were collected from an independent sample of young and older adults and used as parametric regressors. Across both judgment types, young adults had stronger activation in the dorsomedial prefrontal cortex, a region broadly implicated in theory of mind. Moreover, higher activation in the dorsomedial prefrontal cortex in response to deception and awkwardness was associated with older adults' higher theory of mind performance on an unrelated task. The brain activity involved in decoding concurrent mental states may provide unique insight into older adults' theory of mind deficits.