The Neurobiology of Social Distance

Abstract

Never before have we experienced social isolation on such a massive scale as we have in response to coronavirus disease 2019 (COVID-19). However, we know that the social environment has a dramatic impact on our sense of life satisfaction and well-being. In times of distress, crisis, or disaster, human resilience depends on the richness and strength of social connections, as well as on active engagement in groups and communities. Over recent years, evidence emerging from various disciplines has made it abundantly clear: perceived social isolation (i.e., loneliness) may be the most potent threat to survival and longevity. We highlight the benefits of social bonds, the choreographies of bond creation and maintenance, as well as the neurocognitive basis of social isolation and its deep consequences for mental and physical health.

Keywords: friendship; loneliness; mass isolation; social boycott; social brain.

Figure 1

Emotional Closeness Depends on Contact Frequency. Change in mean emotional closeness (indexed by a 1–10 analog scale) to all members of the extended family (unfilled dots) and all the friends they had at the start of the study (filled dots) over 18 months after the participant had moved away from home (at month 6) and could no longer meet with these individuals in person. Emotional closeness at the start of the study is set at 0 for both groups. Reproduced, with permission, from [61].

Figure 2

Quantitative Map of How Much Social Touching Is Allowed for Different Body Regions. In 1368 people from several countries, this study investigated the permissibility of social touch [165]. The authors showed that human social touch is particularly dependent on the nature of the relationship. The topography of accepted social touching depends on many factors, including (i) emotional relationship, (ii) type of interpersonal bond including kinship, (iii) sex, and (iv) power dynamics. Close acquaintances and family members are touched for more different reasons. Culture influence, measured in five countries, was small. Female, rather than opposite-sex, touch was evaluated as being more pleasant, and it was consequently allowed on larger areas of the body. Reproduced, with permission, from [165]. Abbreviation: Acq, acquaintance (distant).

Figure 3

Amygdala Damage Leads to Disturbed Management of One’s Comfort Zone. The scale in (A) shows the chin-to-chin distance between experimenter and participant. A patient with bilateral amygdala lesion (B, red line and image) preferred closer distance to the experimenter (C, black image), without expressing any sense of discomfort, compared to 15 matched neurotypical controls (blue lines and image). The authors also report fMRI data [127] confirming that neural activity responses in the amygdala are implicated in the management of one’s personal space. This observation is in line with other studies of amygdalar involvement in various approach–avoidance decisions, such as social judgments of attractiveness or trustworthiness from other’s faces (e.g., [82,83,93]). Reproduced, with permission, from [127].