Serotonin is involved in many neurovegative functions. Strategies to investigate the role of serotonin in mood disorders have employed similar strategies as described in the catecholamine hypothesis.

In addition, such reductions in 5-HIAA are also seen in patients with impulsivity.

A common sleep problem in depression is that of midnight awakenings and early morning awakening. Sleep EEG recordings show that this is the result of reduced slow wave sleep. Such reductions of SWS has been produced by methods that reduce 5HT centrally.

    Evidence for role of serotonin in depression

    Depressesion causes and treatment

  • Post mortem studies- suicide victims have decrease 5HT and 5HLAA and 5HT receptors in brain;
  • Plasma tryptophan is low in depressed phase and normalizes with recovery;
  • Low 5HLAA in violent suicide victims and patients with impulsivity;
  • Reduced slow wave sleep