Social interactions and loneliness in daily life: A study of younger adults and cognitively diverse older adults.

Feeling lonely is a common experience across the lifespan and people's feelings of loneliness often do not correspond with their levels of social interaction in expected ways (i.e., social asymmetry). It is unclear, however, whether loneliness in daily life differs by age or cognitive status and how loneliness varies as a function of social interaction across age and cognitive status. The present research used experience sampling to investigate group differences in loneliness and social interaction in the daily lives of individuals (N = 219; Rangeage = 21-84; 57% women; 67% White), including younger adults (Mage = 27), cognitively unimpaired older adults (Mage = 75), and older adults with mild cognitive impairment (MCI; Mage = 77). Compared with older adults, younger adults reported being lonelier and their loneliness was more strongly tied to recent social interactions (i.e., greater reductions in loneliness vs. when no recent interaction). In contrast, relative to younger adults, cognitively unimpaired older adults demonstrated an attenuated negative relation between their social interactions and loneliness levels and no such association was present for older adults with MCI. Across groups loneliness was lower after social interactions that occurred face-to-face, but partner closeness primarily mattered for reduced loneliness in older adults with MCI. The findings suggest younger adults are particularly vulnerable to experiencing loneliness in their daily lives, and frequent face-to-face social interactions may serve as a buffer against loneliness. Although older adults may feel less lonely on average, older adults with MCI may be especially likely to experience social asymmetries. (PsycInfo Database Record (c) 2026 APA, all rights reserved).