Neuropharmacology And NeurotoxicologyAmygdala response to both positively and negatively valenced stimuliGaravan, Hugh1,2, CA; Pendergrass, J. Cara3; Ross, Thomas J.2; Stein, Elliot A.2,4; Risinger, Robert C.2Author Information 1Department of Psychology, Trinity College, Dublin 2, Ireland; 2Department of Psychiatry and Behavioral Medicine and the 4Biophysics Research Institute, Medical College of Wisconsin, 8701 Watertown Plank Rd., Milwaukee, WI 53226; 3Finch University of Health Sciences, Chicago Medical School, 3333 Green Bay Road, North Chicago, IL 60064, USA CA,1Corresponding Author and Address Received 28 March 2001; accepted 2 July 2001 Neuroreport: August 28th, 2001 - Volume 12 - Issue 12 - p 2779-2783 Buy SDC Abstract Human lesion and functional imaging data suggest a central role for the amygdala in the processing of negative stimuli. To determine whether the amygdala's role in affective processing extends beyond negative stimuli, subjects viewed pictures that varied in emotional content (positive vs negative valence) and arousal level (high vs low) while undergoing functional magnetic resonance imaging. Amygdala activation, relative to a low arousal and neutral valence picture baseline, was significantly increased for both positively and negatively valenced stimuli and did not differ for the two valences. There were no laterality effects. Whereas arousal level appeared to modulate the amygdala response for negative stimuli, all positively valenced pictures (both high and low in arousal) produced significant amygdala responses. These results clearly demonstrate a role for the amygdala in processing emotional stimuli that extends beyond negative and fearful stimuli. © 2001 Lippincott Williams & Wilkins, Inc.