In the February 2008 issue of the American Journal of Psychiatry, it was found that children with bipolar disorder and children who have a parent or sibling with bipolar disorder have the same difficulty with reading facial expressions.

Weak connections and differences in activity were found in a brain circuit that interprets the meaning of social and emotional stimuli. These differences were not related to medication.

It may be that difficulties with reading facial expressions may be an inherited predisposition to bipolar disorder.

In a previous study, it was found tha the brain’s amgydala is overactivated when children with bipolar disorder misread neutral facial expressions as threatening.