A new study finds that brief isolation increases threat sensitivity in teens, even if they remain connected online. Adolescents isolated in a room for several hours showed heightened physiological stress and anxious responses to potential threats, regardless of whether they had access to smartphones.

A large meta-analysis of over 600,000 people shows that experiencing loneliness significantly raises the risk of developing dementia by 31%. Researchers found that loneliness is a key factor in cognitive decline, contributing to conditions like Alzheimer's disease, regardless of age or sex.