Impaired selective fear learning has been advanced as a core mechanism involved in excessive spreading of protective responses such as pain-related fear and avoidance leading to disability in chronic pain conditions. Using the litmus test for selective learning effects, the blocking procedure, we tested the hypothesis that patients with fibromyalgia (FM) show less selective threat learning than healthy controls (HCs). We introduce a novel selective learning task based around a clinical diary scenario. On a trial-by-trial basis, participants rated whether they expected certain situations (A, B, Z, and X) in the diary of a fictive FM patient would trigger pain in that patient. The procedure did not involve any experimental pain induction because the verbal outcomes “pain” or “no pain” were used. During the elemental acquisition phase, one situation was followed by “pain” (A+, eg, “Kim slept badly, and reports pain”), whereas another situation was followed by “no pain” (Z−, eg, “Kim was stressed, and reports no pain”). During the compound acquisition phase, another situation (X), referred to as the blocked stimulus, was presented in compound with a previously pain-eliciting situation and also paired with “pain” (AX+, eg, Kim slept badly” and “Kim has vacuumed,” and reports pain). Simultaneously, a novel situation was introduced and also followed by “pain” (B+). Within-group comparisons showed blocking (ie, significant difference between B and X) in the HCs, but not in the patients with FM. This study is the first in directly assessing differences in selective learning between patients with FM and HCs using a blocking procedure.
Patients with fibromyalgia show impaired selective learning in pain expectancy judgments compared with healthy controls in a contingency learning task based around a clinical diary scenario.
aResearch Group Health Psychology, KU Leuven, Leuven, Belgium
bCenter for Excellence Generalization on Research in Health and Psychopathology, KU Leuven, Leuven, Belgium
cDepartment of Clinical Psychological Science, Research Group Behavioral Medicine, Maastricht University, the Netherlands
dDepartment of Clinical Psychology, University of Groningen, Groningen, the Netherlands
eCenter for the Psychology of Learning and Experimental Psychopathology, KU Leuven, Leuven, Belgium
fLaboratory of Experimental Psychology, University of Deusto, Bilbao, Spain
Corresponding author. Address: Department of Psychology, KU Leuven, Tiensestraat 102, Box 3726, 3000 Leuven, Belgium. Tel.: +32 (0)16 32 60 38; fax: +32 (0)16 32 61 44. E-mail address: firstname.lastname@example.org (A. Meulders).
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Received September 06, 2017
Received in revised form March 02, 2018
Accepted March 06, 2018