Lifespan aging and belief reasoning: Influences of executive function and social cue decoding.

Older adults often perform poorly on Theory of Mind (ToM) tests that require understanding of others' beliefs and intentions. The course and specificity of age changes in belief reasoning across the adult lifespan is unclear, as is the cause of the age effects. Cognitive and neuropsychological models predict that two types of processing might influence age differences in belief reasoning: executive functioning and social cue detection. In the current study we assessed 129 adults aged between 18 and 86 on novel measures of ToM (video clips and verbal vignettes), which manipulated whether true or false belief reasoning was required. On both video and verbal tasks, older adults (aged 65-88) had specific impairments in false belief reasoning, but showed no such problem in performing true belief tasks. Middle-aged adults (aged 40-64) generally performed as well as the younger adults (aged 18-39). Difficulties in updating information in working memory (but not inhibitory problems) partially mediated the age differences in false belief reasoning. Also, the ability to decode biological motion, indexing social cue detection, partially mediated age-related variance in the ability to interpret false beliefs. These results indicate that age differences in decoding social cues and updating information in memory may be important influences on the specific problems encountered when reasoning about false beliefs in old age.