Serotonergic functioning and trait-impulsivity in attention-deficit/hyperactivity-disordered boys (ADHD): influence of rapid tryptophan depletion

Hum Psychopharmacol. 2008 Jan;23(1):43-51. doi: 10.1002/hup.896.

Abstract

Objective: The present study investigated the effects of rapid tryptophan depletion (RTD) and the ensuing reduction of central nervous levels of serotonin (5-HT) on reactive aggression with respect to personality factors comprising aspects of trait-impulsivity and -aggression in boys with attention-deficit/hyperactivity-disorder (ADHD).

Methods: Twenty-two male adolescent patients with ADHD received the RTD test on one day, and, on another day a tryptophan balanced placebo in a double-blind within-subject crossover design. Impulsive personality factors and trait-impulsivity were assessed in advance of the study. Aggression was provoked using a competitive reaction time game 270 min after RTD/placebo intake.

Results: RTD had a significant effect on increased aggressive behaviour with which low-grade impulsive patients responded. High-grade impulsive patients were not affected by RTD or even responded with increased aggressive behaviour while receiving placebo treatment.

Conclusions: The present study supports the hypothesis that 5-HT functioning in ADHD patients influences reactive aggression depending on aspects of trait-impulsivity. Future studies are necessary in order to detect the specific influence of ADHD as regards the relevance to 5-HT-induced changed aggressive responding.

Publication types

  • Clinical Trial
  • Randomized Controlled Trial
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Aggression
  • Attention Deficit Disorder with Hyperactivity / complications
  • Child
  • Cross-Over Studies
  • Diet, Reducing / adverse effects*
  • Double-Blind Method
  • Drug Administration Schedule
  • Humans
  • Impulsive Behavior / etiology
  • Impulsive Behavior / metabolism*
  • Male
  • Psychiatric Status Rating Scales
  • Reaction Time / physiology
  • Serotonin / metabolism*
  • Tryptophan / deficiency*

Substances

  • Serotonin
  • Tryptophan