Social isolation and the brain: effects and mechanisms

Area of Science:

• Neuroscience
• Developmental Psychology
• Public Health

Background:

• The COVID-19 pandemic caused widespread social isolation (SI), raising concerns about its impact on brain health from infancy to adulthood.
• While social development in isolation is studied, the precise mechanisms of SI-induced brain dysfunction remain unclear due to human study complexity and animal model limitations.

Approach:

• This systematic review synthesizes findings on brain alterations (molecular, cellular, structural, functional) caused by SI across different ages and animal models.
• It examines common socioemotional and cognitive deficits in early life and increased depression and anxiety in later life linked to SI.

Key Points:

• SI induces alterations in neurotransmission and neural circuitry, alongside abnormal glial cell development and function, contributing to emotional and behavioral changes.
• Distinct changes in oligodendrocyte progenitor cell differentiation (early life) and maturation (later life) due to SI can impair neural circuit formation and function.
• The review highlights the need for better animal models that mirror human brain structures and complex social behaviors to bridge research gaps.

Conclusions:

• Social isolation profoundly affects brain development and function across the lifespan, leading to significant socioemotional and cognitive impairments.
• Understanding the specific cellular and circuit-level changes induced by SI is essential for mitigating its adverse neurological consequences.
• Developing more translatable animal models is critical for advancing research on the human brain's response to social isolation.