Reduced serotonergic functioning changes heart rate in ADHD.

Department of Child and Adolescent Psychiatry and Psychotherapy, Goethe University of Frankfurt am Main, Deutschordenstr, Frankfurt, Germany.
Journal of Neural Transmission (Impact Factor: 2.87). 12/2008; 116(1):105-8. DOI: 10.1007/s00702-008-0146-0
Source: PubMed

ABSTRACT Reduced mean heart rate (HR) was shown to be a biophysiological marker for aggression, which in turn was proven to be related to changed serotonergic neurotransmission. A total of 16 ADHD-diagnosed boys were subjected to rapid tryptophan depletion (RTD) and a placebo in a double-blind within-subject crossover-design. Mean HR was assessed under RTD/placebo. Low impulsive patients behaving aggressively under RTD showed a lowered HR under RTD versus placebo. Diminished 5-HT functioning was associated with lowered HR and aggressive behaviour.