Depressive Disorders: Etiology

The etiology of depressive disorders includes biological, psychological, and sociocultural factors.

Biological factors such as genes, particularly variations in the serotonin transporter gene, increase the risk of depression, especially in stressful social environments.

Individuals with depression exhibit lower brain activity in a section of the prefrontal cortex responsible for generating actions.

It is linked to low serotonin and norepinephrine levels, diminished neurogenesis, reduced hippocampal volume, and decreased dopamine, explaining the difficulty in experiencing pleasure.

Psychological factors like learned helplessness develop when individuals face repeated exposure to uncontrollable negative events, leading to depression and hopelessness.

Cognitive distortions, like overgeneralizing or magnifying failures, create negative perceptions of oneself and the world, contributing to depression.

A pessimistic attributional style, where internal, stable, and global factors are blamed for negative outcomes, further increases vulnerability.

Sociocultural factors such as low socioeconomic status increase the risk of depression, especially in poverty, worsening with declining living standards or employment.