Social Connections Enhance Brain Health

From the beginning of life, the healthy brain relies on relationships. “We would not survive without social interaction,” says Laura Carstensen, professor of psychology and founding director of the Stanford Center on Longevity at Stanford University. “We are hardwired to form attachments and to be engaged with others.” That’s why being social is one of Staying Sharp’s six pillars of brain health.

Yet 40 percent of adults surveyed by AARP in August 2025 reported feeling lonely. Cognitive health is an important reason to find ways to feel less lonely and connect with others.

Getting together with friends or family — to play cards, for example, share a meal, discuss books or attend religious services — seems to protect cognitive function. And although the research doesn’t prove that nurturing relationships cause a healthy brain, Carstensen says, the link is compelling.

Social connections and engagement may reduce the risk of dementia and are associated with better brain function, emerging research has shown. In a study of 7,299 adults ages 60 and older, published in 2024 in Alzheimer’s & Dementia: The Journal of the Alzheimer’s Association, those who experienced persistent loneliness or social isolation over a period of at least three years had faster cognitive decline and a higher risk of cognitive impairment than those who were not lonely or isolated.

Similarly, older adults who said they rarely or never felt lonely performed better on cognitive tests than those who were the loneliest in a meta-analysis of seven studies, involving more than 20,000 participants ages 50 and older, published in Psychological Medicine in 2025.

The size of your social network may make a difference, too. Having a large and diverse group of close family and friends may help protect against depression, according to a systematic review of 127 studies of adults with a mean age of at least 60 published in 2024 in Systematic Reviews. For people who have dementia, social connection and activity may offer cognitive benefits, too, evidence suggests.

Researchers attribute these brain benefits to the rush of neurotransmitters released when humans are in the company of others. “Our best guess is that the brain is getting more oxytocin [the “bonding hormone”], dopamine and serotonin,” says Lou Cozolino, a psychologist and professor of psychology at Pepperdine University. “The activation of all those things increases the sense of well-being and decreases stress.”