New research, published in the journal PLOS One, shows that keeping strong friendships into old age may stave off mental decline. The new study was carried out by researchers from the Cognitive Neurology and Alzheimer's Disease Center (CNADC) at Northwestern University Feinberg School of Medicine in Chicago, IL. Emily Rogalski, associate professor at CNADC, is the senior author of the paper, and Amanda Cook, a clinical neuropsychology doctoral student in the laboratory of Rogalski and Sandra Weintraub, is the first author. Rogalski and team examined the social network and cognitive abilities of a group of so-called SuperAgers – people who are in their 80s but have the mental agility of those in their 50s or 60s. This is the first time that the social aspect of this population sample has been studied.

Rogalski and her colleagues asked 31 SuperAgers and 19 age-matched controls to complete a 42-item questionnaire that enquired about their psychological well-being. The questions spanned across six criteria: "autonomy, positive relations with others, environmental mastery, personal growth, purpose in life, and self-acceptance." Participants were at least 80 years old, and their episodic memory was "at least as good" as that of their middle-aged peers. Episodic memory is defined as "the capacity to recall specific experiences, as if one were to 'mentally time travel' to re-experience individual events."