title: Deficient modulation of pain by a positive emotional context in fibromyalgia patients.
abstract: This study aimed to investigate the modulating effects of emotional context on pain perception in 16 patients with fibromyalgia syndrome (FMS) and 16 healthy control (HC) subjects. An infrared laser was used to apply individually adapted painful stimuli to the dorsum of the left hand. The emotional background of the painful stimuli was modulated by concurrent presentations of negative, neutral, and positive picture stimuli selected from the International Affective Picture System. As control conditions, painful stimuli and the pictures were also presented by themselves. During each of the 5 laser-picture trials, subjects received 10 painful stimuli and were asked to rate the average intensity and unpleasantness of the experienced pain. Functional magnetic resonance images were obtained, using a T2(∗) sensitive echo planar sequence. HC subjects showed a linear increase in pain intensity and unpleasantness ratings when painful stimuli were presented during positive, neutral, and negative pictures. In contrast, FMS patients showed a quadratic trend for pain intensity ratings indicating a lack of pain reduction by the positive pictures. In addition, the FMS patients showed less activation in secondary somatosensory cortex, insula, orbitofrontal cortex, and anterior cingulate cortex during the positive picture pain trials. Our results suggest that fibromyalgia patients are less efficient in modulating pain by positive affect and may benefit less from appetitive events than healthy control subjects.
authors.affiliation: Department of Cognitive and Clinical Neuroscience, Central Institute of Mental Health, Medical Faculty Mannheim, Heidelberg University, Mannheim, Germany Max Planck Institute for Human and Cognitive Brain Sciences, Department of Social Neuroscience, Leipzig, Germany.
authors.forename: Sandra
authors.initials: S
authors.lastname: Kamping
authors.forename: Isabelle C
authors.initials: IC
authors.lastname: Bomba
authors.forename: Philipp
authors.initials: P
authors.lastname: Kanske
authors.forename: Eugen
authors.initials: E
authors.lastname: Diesch
authors.forename: Herta
authors.initials: H
authors.lastname: Flor
mesh_terms: D000328:Adult; D000342:Affective Symptoms / Q000209:etiology*; D000368:Aged; D001931:Brain Mapping; D005260:Female; D005356:Fibromyalgia / Q000150:complications*; D006225:Hand / Q000294:innervation; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008279:Magnetic Resonance Imaging; D008875:Middle Aged; D010146:Pain / Q000209:etiology* / Q000473:pathology*; D010147:Pain Measurement; D017288:Pain Threshold / Q000502:physiology*; D010775:Photic Stimulation; D012044:Regression Analysis; D011795:Surveys and Questionnaires; D013997:Time Factors
keywords: Emotion; Fibromyalgia; Imaging; Modulation