Serotonin Transporter Genotype (5-HTTLPR): Effects of Neutral and Undefined Conditions on Amygdala Activation

Heinz, Andreas; Smolka, Michael N.; Braus, Dieter F.; Wrase, Jana; Beck, Anne; Flor, Herta; Mann, Karl; Schumann, Gunter; Büchel, Christian; Hariri, Ahmad R.; Weinberger, Daniel R.

doi:10.1016/j.biopsych.2006.08.019

« Previous Next »Biological Psychiatry
Volume 61, Issue 8 , Pages 1011-1014, 15 April 2007

Serotonin Transporter Genotype (5-HTTLPR): Effects of Neutral and Undefined Conditions on Amygdala Activation

Andreas Heinz
- Department of Psychiatry, Charité University Medicine Berlin, Campus Charité Mitte, Germany
Michael N. Smolka
- Central Institute of Mental Health, Mannheim, Germany
Dieter F. Braus
- Department of Psychiatry, NeuroImage Nord, University Clinic Hamburg-Eppendorf, Germany
Jana Wrase
- Department of Psychiatry, Charité University Medicine Berlin, Campus Charité Mitte, Germany
Anne Beck
- Department of Psychiatry, Charité University Medicine Berlin, Campus Charité Mitte, Germany
Herta Flor
- Central Institute of Mental Health, Mannheim, Germany
Karl Mann
- Central Institute of Mental Health, Mannheim, Germany
Gunter Schumann
- Institute of Psychiatry, London, United Kingdom
Christian Büchel
- Department of Systemic Neuroscience, NeuroImage Nord, University Clinic Hamburg-Eppendorf, Germany
Ahmad R. Hariri
- Department of Psychiatry, University of Pittsburgh, Pennsylvania
Daniel R. Weinberger
- National Institute of Mental Health, National Institutes of Health, Bethesda, Maryland.
- Address reprint requests to Daniel R. Weinberger, M.D., Genes, Cognition and Psychosis Program, National Institute of Mental Health, National Institutes of Health, Room 4S-235, 10 Center Drive, Bethesda, MD 20892

Received 24 January 2006; received in revised form 29 June 2006; accepted 21 August 2006. published online 08 December 2006.

Background

A polymorphism of the human serotonin transporter gene (SCL6A4) has been associated with serotonin transporter expression and with processing of aversive stimuli in the amygdala. Functional imaging studies show that during the presentation of aversive versus neutral cues, healthy carriers of the short (s) allele showed stronger amygdala activation than long (l) carriers. However, a recent report suggested that this interaction is driven by amygdala deactivation during presentation of neutral stimuli in s carriers.

Methods

Functional MRI was used to assess amygdala activation during the presentation of a fixation cross or affectively aversive or neutral visual stimuli in 29 healthy men.

Results

Amygdala activation was increased in s carriers during undefined states such as the presentation of a fixation cross compared with emotionally neutral conditions.

Conclusions

This finding suggests that s carriers show stronger amygdala reactivity to stimuli and contexts that are relatively uncertain, which we propose are stressful.

Key Words: 5-HTT genotype, amygdala, baseline, emotion, fixation cross, functional MRI