a1 Department of Neurology, Oregon Health & Science University, Portland, OR, USA
a2 Oregon Center for Aging and Technology, Oregon Health & Science University, Portland, OR, USA
a3 Department of Neurology, University of Michigan Health System, Ann Arbor, MI, USA Email: email@example.com
a4 Department of Psychology, Research Center for Group Dynamics, Institute of Social Research, University of Michigan , Ann Arbor, MI, USA
a5 Neurology Service, Portland Veteran Affairs Medical Center, Portland, OR, USA
a6 Department of Biomedical Engineering, Oregon Health and Science University, Portland, OR, USA
People are good for your brain. Decades of research have shown that individuals who have a larger number of people in their social network or higher quality ties with individuals within their network have lower rates of morbidity and mortality across a wide range of health outcomes. Among these outcomes, cognitive function, especially in the context of brain aging, has been one area of particular interest with regard to social engagement, or more broadly, socially integrated lifestyles. Many studies have observed an association between the size of a person's social network or levels of social engagement and the risk for cognitive decline or dementia (e.g. see review by Fratiglioni et al., 2004). The dementia risk reduction associated with a larger social network or social engagement shown by some epidemiological studies is fairly large. The population effect size of increasing social engagement on delaying dementia disease progression could exceed that of current FDA approved medications for Alzheimer's disease.