Anxiety & Depression, Nature or Nurture

Anxiety & Depression, Nature or Nurture

Aired Thursday, September 12, 2019 at 1:00 PM PST / 4:00 PM EST

Pennie and Matthew will be discussing whether Anxiety & Depression are affected by nature or nurture. Depression is one of the most common forms of psychopathology. According to diathesis–stress theories of depression, genetic liability interacts with negative life experiences to cause depression. Traditionally, most studies testing these theories have focused on only one component of the diathesis–stress model: either genetics or environment, but not their interaction. However, because of recent advances in genetics and genomics, researchers have begun using a new design that allows them to test the interaction of genetic and environmental liabilities – the G x E design.

Studies suggest that the neurotransmitter dopamine may play a role in the risk for depression. Early negative interpersonal environments (i.e. rejecting parents) have also been implicated.

The researchers studied 177 male adolescents from a juvenile detention centre in Russia. These participants were ideal candidates for the study because depression rates rise so dramatically during this period in life. The researchers used a structured diagnostic interview to diagnose depression and a questionnaire to assess aspects of maternal parental rearing (i.e. physical punishment, hostility, lack of respect for the child’s point of view, and unjustified criticism in front of others).

The results are fascinating. While neither factor alone predicted depression, the boys with especially rejecting mothers, and a specific form of the dopamine transporter gene were at higher risk for major depression and suicidal ideation.

By the year 2020, anxiety and depression are projected to be the 2nd leading cause of disability worldwide.