Daniel Weinstein et al., “Singing and Social Bonding: Changes in Connectivity and Pain Threshold as a Function of Group Size,” Evolution and Human Behavior 37, no. 2 (2016): 152–158; Gene D. Cohen et al., “The Impact of Professionally Conducted Cultural Programs on the Physical Health, Mental Health, and Social Functioning of Older Adults,” Gerontologist 46, no. 6 (2006): 726–734.