, 203:53

Acute tryptophan depletion and self-injurious behavior in aggressive patients and healthy volunteers


    • Department of PsychiatryUniversity of Chicago
  • Dror Ben-Zeev
    • Department of PsychologyIllinois Institute of Technology
  • Royce Lee
    • Department of PsychiatryUniversity of Chicago
  • Mitchell E. Berman
    • Department of PsychologyUniversity of Southern Mississippi
  • Emil F. Coccaro
    • Department of PsychiatryUniversity of Chicago
Original Investigation

DOI: 10.1007/s00213-008-1374-6

Cite this article as:
McCloskey, M.S., Ben-Zeev, D., Lee, R. et al. Psychopharmacology (2009) 203: 53. doi:10.1007/s00213-008-1374-6



An association between serotonin (5-HT) activity and self-injurious (i.e., self-aggressive) behavior across the spectrum of lethality (from self-mutilation through completed suicide) is a well-replicated finding. Studies to date, however, have relied on nonexperimental designs to examine this relationship, limiting the causal inferences that can be drawn about the role of 5-HT in self-aggressive behavior.


Examine the effect of experimentally altered 5-HT activity (via dietary tryptophan depletion) on self-aggressive behavior among adults with and without intermittent explosive disorder (IED). Individuals with a marked history of aggression, such as those with IED, are characterized by compromised 5-HT and heightened risk for self-aggression, making this a population of interest for examining the proposed relations.

Materials and methods

IED patients (n = 16) and healthy controls (n = 16) received a tryptophan depletion and a placebo drink on separate days at least 1 week apart. Self-aggressive behavior was assessed on both study days using a well-validated laboratory-based behavioral assessment with self-aggression defined as the intensity of shock self-administered.


Tryptophan depletion facilitated selection of more intense shocks, on average, in both groups. Patients with IED were also more self-aggressive overall than healthy volunteers. No IED by drink condition interactions were found.


Experimentally lowered 5-HT bioavailability enhances overall self-injurious behavior irrespective of aggression history.


Self-aggressionSerotoninTryptophan depletionIntermittent explosive disorder

Copyright information

© Springer-Verlag 2008