Bereft and Left: The interplay between insecure attachment, isolation, and neurobiology

Being isolated from a group is associated with health risks, depressive symptomology, and increased risk-taking behaviors. A growing body of literature suggests that the way individual experiences isolation is a moderator of these negative health risks. How an individual perceives loneliness may be a product of one’s social environment: namely, an individual’s attachment style may indicate the extent to which he or she experiences feelings of loneliness. This is particularly relevant in the recent climate of social isolation due to COVID-19 restrictions and future pandemic response. The goal of this paper is to review and consolidate research in the domains of both loneliness and attachment and demonstrate how the two cyclically affect one another. We review the literature from a neurobiological point of view to explore the underlying bidirectional relationships between an individual’s genetics, neuroendocrine system, and neuroanatomy, and an individual’s attachment style with their primary caregiver. By examining animal models of loneliness and attachment we can see the behavioral and biological similarities between humans and animals, highlighting the importance of these types of studies. Finally, we summarize the current research and propose that the underlying biological systems of loneliness and attachment represent bidirectional, multigenerational, gene-environment interactions.