In health, emotions are integrated with autonomic bodily
responses. Emotional stimuli elicit changes in somatic
(including autonomic) bodily states, which feedback to
influence the expression of emotional feelings. In patients with
spinal cord injury (SCI), this integration of emotion and bodily
arousal is partially disrupted, impairing both efferent generation
of sympathetic responses and afferent sensory feedback of
visceral state via the spinal cord. A number of theoretical
accounts of emotion predict emotional deficits in SCI patients, particularly at the level of emotional
feelings, yet evidence for such a deficit is equivocal. We used functional MRI (fMRI) and a basic
emotional learning paradigm to investigate the expression of emotion-related brain activity
consequent upon SCI.
We suggest that the observed functional abnormalities including enhanced anterior cingulate and PAG reflect central sensitization of the pain matrix, while decreased subgenual cingulate activity may represent a substrate underlying affective vulnerability in SCI patients consequent upon perturbation of autonomic control and afferent visceral representation. Together these observations may account for motivational and affective sequelae of SCI in some individuals.
Alessia Nicotra1,2, Hugo D. Critchley1,3,4,
Christopher J. Mathias1,2 and Raymond J. Dolan3
Brain 2006 129(3):718-728; doi:10.1093/brain/awh699