Mandated curfews, lockdowns, and isolation periods - with the resurgence of COVID-19 cases around the world over the past two years, the implementation of various infection control measures have exacerbated the mental wellbeing of the global population at a remarkable scale [1]. Historically, communicable diseases and their transmission from an affected patient to unaffected individuals have accelerated the development of preventative infection control with an unspoken acknowledgement of its repercussions for long-term mental health outcomes. For many, celebrating the holiday season this year has been a conspicuous anomaly: in fact, the inability to meaningfully reconnect with family and friends has coerced 18% of Americans to feel as if they have severed closely held social connections in their life, catalyzing what many scientists have characterized as the “Double Pandemic” [2].
Throughout human evolution, interpersonal dependency has manifested itself as a salient component of flourishing social relationships, and ultimately, as a pervasive modulator of cognition, life expectancy, and in some estimates, even the emergence of senescence-related neurodegenerative disorders [3]. Therefore, it may not be surprising to reconcile why the very perception of loneliness sufficiently casts a menacing shadow over the unique neural patterning signatures associated with selection pressures for sociality [4]. The nature of social exchange is a sophisticated one; encompassing higher-order neurocognitive mechanisms which allow an agent to synthesize coherent thoughts and intentions.
Recently, however, a compelling study conducted by neuroscience researchers at McGill University has advanced some more nuanced insight into the neural correlates for unmet desires for social interactions in humans, suggesting a link with the evolution of higher-order associative cortical regions and their biological profiles. The multi-modal imaging-genetics cohort, organized by the UK BioBank initiative and constituted by 40,000 adults, elucidated how lonely individuals exhibit greater volumes of gray and distinct white matter structure, in addition to increased functional connectivity in brain regions dedicated to wakeful rest, or default mode networks (DMNs) [5].
Default networks, by definition, is a term used to describe a collection of several brain regions that are engaged when focus is diverted to contemplating tasks beyond the real world [6]. Conversely, it might be convenient to consider DMNs as active during periods of idled existence - whether that's daydreaming of the alternatives, resmicing over the past, or refining your expectations for the future. Implicated in the mental representation of the self and other social agents across space and time, simulating for intentions, identities, and motivations [7]. In the study, chronic abstention from intimate social connections was deemed as a significant predictor of shifted functional activity in the brain, leading the researchers to believe sustained loneliness carries broad implications for our brain’s architecture.
The neuroscience of loneliness and its consequential implications for public health policymaking remains a dormant avenue of research. However, with novel endeavors to understand how social deprivation manifests itself as increased self-reflection in the mind, the urgency for mitigating loneliness in today’s society becomes increasingly clear.
References
Greenberg, M. Do Lonely People Have Different Brains? Psychology Today - Sussex publishers [Online] 2020. https://www.psychologytoday.com/us/blog/the-mindful-self-express/202012/do-lonely-people-have-different-brains
Holt-Lunstad, J. The Double Pandemic Of Social Isolation And COVID-19: Cross-Sector Policy Must Address Both. Health Affairs Forefront Blog - Project Hope [Online] 2020. https://www.healthaffairs.org/do/10.1377/forefront.20200609.53823
Spreng, R. The default network of the human brain is associated with perceived social isolation. Nature Communications - Springer Nature [Online] 2020. https://www.nature.com/articles/s41467-020-20039-w
Spreng, R. "Lonely brain" imaging study reveals unexpected neural patterns. New Atlas [Online] 2020. https://newatlas.com/science/loneliness-brain-imaging-study-neural-signature-default-mode/
Andrews-Hanna, J. Functional-anatomic fractionation of the brain's default network. ScienceDirect - Neuron Cell Press [Online] 2010. https://pubmed.ncbi.nlm.nih.gov/20188659/
Allen, S. The associations between loneliness, social exclusion and pain in the general population. ScienceDirect - Journal of Psychiatric Research [Online] 2020. https://pubmed.ncbi.nlm.nih.gov/32791383/
Mars, R. On the relationship between the “default mode network” and the “social brain”. Human Cognitive Neuroscience - Frontiers Media [Online] 2012. https://www.frontiersin.org/articles/10.3389/fnhum.2012.00189/full
McCrimmon, K. Loneliness during the COVID-19 pandemic: Fight it with kindness. UCHealth Today Digest - UCHealth Publishers [Online] 2020. https://www.uchealth.org/today/loneliness-during-the-covid-19-pandemic-fight-it-with-kindness/