A 2021 research review looked at the neurobiological, psychosocial and behavioral correlations of decreased physical touch during the COVID-19 pandemic. Between the lockdowns and social distancing guidelines, many people have been going without physical touch to an unprecedented degree.
Researchers found that touch activates certain receptors in the brain and releases oxytocin, a neurotransmitter that plays a primary role in attachment, social bonds, mother-child interaction and monogamy. Because of the pandemic restrictions, touch was limited. Researchers found that the limited physical touch resulted in a de-activation of certain receptors in the brain and decreased oxytocin levels which contributed to more stress, weakened immune systems and impaired emotional connection to others.