Functional neuroimaging of reward circuitry responsivity to monetary gains and losses in posttraumatic stress disorder.
BACKGROUND
Clinical impressions and preclinical work suggest that posttraumatic stress disorder (PTSD) might be associated with dysfunctional reward processing. To pursue this issue, we administered a validated passive-viewing monetary reward task during functional magnetic resonance imaging (fMRI) to subjects with chronic PTSD and to mentally healthy individuals.


METHODS
The protocol evaluated fMRI signal changes that anticipated or accompanied monetary gains and losses under varying conditions of controlled expectation. The "expectancy phase" entailed presentation of a promising, unpromising, or intermediate Wheel of Fortune-type spinner, whereas the "outcome phase" was defined by the arrow landing on one of three sectors of that spinner, thereby determining the subjects' gain or loss for that trial.


RESULTS
Neuroimaging data from 20 PTSD and 26 healthy subjects withstood quality control procedures and were included. In voxelwise and anatomically defined region-of-interest analyses, when gains were contrasted to losses, between-group comparison revealed smaller bilateral striatal activations in the PTSD subjects. In the PTSD group, less striatal activation to gains versus losses was associated with more self-reported motivational and social deficits.


CONCLUSIONS
The present data support the hypothesis that PTSD is associated with abnormal processing of monetary outcomes and that this alteration might be related to some aspects of emotional numbing.
Elman
Igor
I
Clinical Psychopathology Laboratory, McLean Hospital and Harvard Medical School, Boston, Massachusetts 02478-9106, USA. ielman@partners.org
Lowen
Steven
S
Frederick
Blaise B
BB
Chi
Won
W
Becerra
Lino
L
Pitman
Roger K
RK
D000328:Adult; D000704:Analysis of Variance; D001921:Brain / Q000098:blood supply / Q000503:physiopathology; D001931:Brain Mapping; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted / Q000379:methods; D008279:Magnetic Resonance Imaging; D008297:Male; D008568:Memory / Q000502:physiology; D008875:Middle Aged; D009415:Nerve Net / Q000098:blood supply*; D010100:Oxygen / Q000097:blood; D012201:Reward; D013313:Stress Disorders, Post-Traumatic / Q000473:pathology* / Q000503:physiopathology; D013997:Time Factors; D055815:Young Adult
D010100:Oxygen