Differential response in the human amygdala to racial... : NeuroReport (original) (raw)

BRAIN IMAGING

Differential response in the human amygdala to racial outgroup vs ingroup face stimuli

Hart, Allen J.2,6; Whalen, Paul J.3; Shin, Lisa M.4; McInerney, Sean C.1; Fischer, Håkan5; Rauch, Scott L.1

1Psychiatric Neuroimaging Research Group and Nuclear Magnetic Resonance Center, Massachusetts General Hospital and Harvard Medical School, 13th St, Bldg. 149, CNY-9 Boston, MA 02129

2Department of Psychology, Amherst College, Amherst, MA 01002

3Departments of Psychiatry and Psychology, University of Wisconsin, 6001 Research Park Blvd., Madison, WI 53719

4Department of Psychology, Tufts University, 490 Boston Ave., Medford, MA 02155, USA

5Uppsala University PET-centre, University Hospital, Uppsala, Sweden

6Corresponding Author: Allen J. Hart

Received 11 April 2000; accepted 11 May 2000

Abstract

Here we describe response in the human amygdala to the presentation of racial outgroup vs ingroup faces. Functional magnetic resonance imaging (fMRI) measures of brain activity were acquired while subjects who identified themselves as White or Black viewed photographs of both White and Black faces. Across all subjects, we observed significantly greater blood oxygen-level-dependent (BOLD) signal in the amygdala to outgroup vs ingroup faces, but only during later stimulus presentations. A region of interest (ROI)-based analysis of these voxels revealed a significant interaction between amygdala response to outgroup and ingroup faces over time. Specifically, the greater amygdala activation to outgroup faces during later stimulus presentations was the result of amygdala response habituation to repeated presentations of ingroup faces with sustained responses to outgroup faces. The present results suggest that amygdala responses to human face stimuli are affected by the relationship between the perceived race of the stimulus face and that of the subject. Results are discussed as consistent with a role for the amygdala in encoding socially and/or biologically relevant information. We conclude that researchers seeking to study brain responses to face stimuli in human subjects should consider the relationship between the race of subjects and stimuli as a significant potential source of variance. Moreover, these data provide a foundation for future related studies in the neuroscience of social cognition and race.