Getting by with a little help from your friends has taken on a new meaning with the discovery that strong friendships keep our brains young. Social creatures, be they humans or killer whales, need others of their own kind and can suffer from weak social networks, but the damage is not always obvious. The latest findings add to a growing picture that our community matters much more than we realize.
Dr Emily Rogalski of Northwestern University is studying SuperAgers, people who have passed 80 but have held onto mental faculties, particularly episodic memory, as acute as a typical person in their 50s or 60s. Unsurprisingly, she has found there is no one magic factor that can guarantee entry into this group. Nevertheless, in PLOS ONE Rogalski and colleagues argue that friendship networks are part of the picture.
"You don't have to be the life of the party, but this study supports the theory that maintaining strong social networks seems to be linked to slower cognitive decline," Rogalski said in a statement.
The study compared 31 SuperAgers with 19 people of average cognitive ability for their age. The researchers found no differences in estimations of the intelligence of the two groups in terms of both age and demographics. Both groups were given a 42-item questionnaire on psychological well being asking them to rate themselves on a six-point scale. The one significant difference was how much better SuperAgers rated their relations with others.
Such studies always leave open the question of the direction of causality. Do better social networks protect against losing cognitive ability, or are people with declining mental faculties less likely to maintain their networks? No longitudinal studies have been done on SuperAgers to answer that question, but just last week a paper was published on research tracking a general sample of elderly people for seven years. This found social isolation to be an identifiable cause of Alzheimer’s disease, rather than an effect.
Rogalski and her co-authors also note research on longitudinal studies of broad populations, which suggest that; “Positive social relationships influence subsequent cognitive performance while the reverse does not appear to be true.” From this, they conclude that for SuperAgers and the general population alike; “It appears that social relationships in and of themselves are important to the maintenance of cognition as opposed to other factors that may enhance or inhibit participation in social relationships.”
Other work has shown that SuperAgers have thicker cortices – parts of the brain that thin with age – than the rest of the population, as well as noticeably better preservation in some other brain regions. They also show less decline in capacity when tracked over significant periods of time.