Rationale: Reducing serotonin by the method of tryptophan depletion (TD) has led to increased aggression but experimental studies have not used female subjects.
Objective: To evaluate the effects of TD on aggression in women in the late luteal phase of their menstrual cycle.
Methods: Healthy women were recruited and randomly assigned to an amino acid drink either depleted or with a balanced amount of tryptophan. At 4.5 h later, they competed on the competitive reaction time task.
Results: Women who had received the TD drink showed more behavioural aggression in response to provocation.
Conclusion: Decreased serotonergic neurotransmission increases aggression in women as well as men.