Harald Kugel1, Christina Sehlmeyer2,3, Udo Dannlowski2,3, Sonja Schoening2,3, Martin Pyka2,3, Astrid Veronika Rauch2,3, Katharina Domschke2, Bettina Pfleiderer1, Pienie Zwitserlood4, Walter Heindel1, Volker Arolt2, Carsten Konrad3,5
1Dept. of Clinical Radiology, University of Muenster, Muenster, NRW, Germany; 2Dept. of Psychiatry, University of Muenster, Muenster, NRW, Germany; 3Research Group 4, Interdisciplinary Center for Clinical Research (IZKF), University of Muenster, Muenster, NRW, Germany; 4Dept. of Psychology, University of Muenster, Muenster, NRW, Germany; 5Dept. of Psychiatry, University of Marburg, Marburg, HE, Germany
The effect of the serotonin transporter polymorphism 5-HTTLPR and trait anxiety on amygdala activation during fear conditioning and extinction was investigated with fMRI. 32 volunteers were tested with a fear-conditioning paradigm, presenting neutral faces combined with an acoustic startle. Individual trait anxiety was determined with the State Trait Anxiety Inventory (STAI). Evaluation showed that trait anxiety and 5-HTTLPR polymorphism did not affect acquisition, but fear extinction. Trait anxious volunteers and carriers of the short s-allele showed less deactivation of the amygdala during extinction, demonstrating that they react strongly to fear stimuli, and they can extinct fear reactions less easily.