New study suggests depression is not caused by low levels of serotonin

New study suggests depression is not caused by low levels of serotonin

For decades, scientists have believed depression is linked to lower levels of serotonin in the brain. But a new study suggests that may not be the case. Dr. Mitch Prinstein, chief science officer at the American Psychological Association, joins CBS News' John Dickerson to discuss the study's findings.