Affiliations: Institut für Medizinische Psychologie und
Verhaltensimmunbiologie, Universitätsklinikum Essen, Hufelandstraße
55, D-45122 Essen. Fax: +49 201 723 5948; E-mail: sigrid.elsenbruch@uk-essen.de
Abstract: While it has long been known that emotional factors can influence
the experience of pain, imaging studies analyzing the neuronal basis of this
effect particularly for visceral stimuli remain scarce. A clarification of this
association is of scientific and clinical interest, particularly in the context
of common functional gastrointestinal disorders which are characterized by a
worsening of symptoms during states of emotional stress. Previous studies
addressing the modulation of the neural response to pain by negative emotions
and stress are critically reviewed herein. Overall, this evidence supports that
the emotional modulation of the neural response to pain involves several brain
regions, including the cingulate cortex – a structure which is activated
by emotions as well as by painful stimuli. Additionally, the insula and
prefrontal cortex play a role. All three brain areas have in common that they
mediate especially the affective components of pain processing. These findings
are apparently not specific for visceral pain since studies applying somatic
pain stimuli show similar results. Together, these results are relevant for the
pathophysiology of various functional pain syndromes given that they could
reveal a neural correlate for the influence stress and negative emotions on
symptom exacerbation. Furthermore, there are a number of important
methodological implications which should be taken into account when designing
and conducting future imaging studies on the neural response to pain.