Neural correlates of deficits in pain-related affective meaning construction in patients with chronic pain disorder.
OBJECTIVE
Psychological and neural mechanisms of the affective dimension of pain are known to be disturbed in patients with chronic pain disorder. The aim of this functional magnetic resonance imaging study was to assess the neurofunctional and behavioral measures underlying the ability to construct pain-related affective meaning in a painful situation by comparing 21 clinically and psychometrically well-characterized patients with persistent non-nociceptive somatoform pain with 19 healthy controls.


METHODS
The functional magnetic resonance imaging task involved viewing pictures depicting human hands and feet in different painful and nonpainful situations. Participants were asked to estimate the perceived pain intensity. These data were correlated with behavioral measures of depression, alexithymia, and general cognitive and emotional empathy.


RESULTS
In a hypothesis-driven region-of-interest analysis, the healthy control group exhibited greater activation of the left perigenual anterior cingulate cortex than patients with pain (Montreal Neurological Institute coordinates (x y z)=-8 38 0; cluster extent=54 voxels; T=4.28; p=.006 corrected for multiple comparisons at cluster level). No group differences in the activation of the anterior insular cortex were found. Scores on self-assessment instruments (Beck Depression Inventory I, Interpersonal Reactivity Index, and 20-item Toronto Alexithymia Scale) did not influence neuroimaging results.


CONCLUSIONS
Our results suggest that patients with chronic medically unexplained pain have an altered neural pain perception process owing to decreased activation of empathetic-affective networks, which we interpret as a deficit in pain-related affective meaning construction. These findings may lead to a more specific and detailed neurobiological understanding of the clinical impression of disturbed affect in patients with chronic pain disorder.
Clinic for Psychosomatic Medicine und Psychotherapie, Universitaetsklinikum Ulm, University of Ulm, Albert Einstein Allee 23, D-89081 Ulm, Germany. minohu@gmx.net
Michael
M
Noll-Hussong
Alexander
A
Otti
Afra M
AM
Wohlschlaeger
Claus
C
Zimmer
Peter
P
Henningsen
Claas
C
Lahmann
Joram
J
Ronel
Claudia
C
Subic-Wrana
Richard D
RD
Lane
Jean
J
Decety
Harald
H
Guendel
D000223:Adaptation, Psychological; D000342:Affective Symptoms / Q000503:physiopathology*; D000704:Analysis of Variance; D001931:Brain Mapping / Q000379:methods; D016022:Case-Control Studies; D002540:Cerebral Cortex / Q000503:physiopathology*; D059350:Chronic Pain / Q000503:physiopathology* / Q000523:psychology; D003863:Depression / Q000503:physiopathology; D056348:Emotional Intelligence / Q000502:physiology; D004645:Empathy / Q000502:physiology*; D005260:Female; D006179:Gyrus Cinguli / Q000503:physiopathology; D006801:Humans; D007406:Interview, Psychological; D008279:Magnetic Resonance Imaging / Q000379:methods; D008297:Male; D008875:Middle Aged; D010147:Pain Measurement; D058748:Pain Perception / Q000502:physiology*; D010775:Photic Stimulation / Q000379:methods; D057566:Self Report; D013001:Somatoform Disorders / Q000503:physiopathology* / Q000523:psychology