Resilience Factors and Selective Learning in Patients With Fibromyalgia

Selective learning will be experimentally investigated by using the blocking procedure. The blocking effect is one mechanism that can provide information about selective learning. In this procedure, one event (A+) will be first paired with pain. Participants should learn the relation between this event and the occurrence of pain. After, another event (x), i.e. the blocking stimulus, is displayed with the first event A (AX+). The combination of both events will also be associated with pain. It will be tested, to which extent participants expect pain for the blocking stimulus alone. In case of "blocked", i.e. reduced pain expectation for X we can assume adaptive, selective learning.

In the planned study a fictitious diary of a fibromyalgia patient will be used as "cover story". Different events and the words "pain" or "no pain" will be visually presented together, indicating in which situation pain occurs and in which not. Participants will be asked to imagine that they are the practitioner trying to learn which situations are associated with pain. This learning experiment is based on a former study by Meulders and colleagues, in which selective learning was investigated by presenting fictitious diary entries, such as "Kim was walking her dog" or "the weather was bad today" (CS) and pairing the sentences in terms of the blocking procedure (see above). In the central test phase, in which events were presented without pain report, participants were asked to give their pain expectations for the different situations. Deficits in selective learning were found in fibromyalgia patients compared to healthy control. For the planned study this learning paradigm will be used with minor adaptations (translated to German, minor instruction adaptations, renamed scale ends, higher scale resolution). The learning experiment will take about 15 minutes.

Positive affect and optimism will be induced through the Best Possible Self (BPS) Intervention. Subjects will be randomly assigned to either the optimism condition or a control condition.

The whole study will be conducted online. Participants will be asked to switch from the experimental platform to the questionnaire platform at various times. In order to recreate the laboratory situation and to keep participants engaged, we implemented several videos in which the virtual investigator guides participants throughout the experiment.

The sample size should include 164 participants, assuming a small effect. A priori power analyses were calculated with the software program G*Power for ANOVA with repeated measures, within-between interaction with a small effect (f=0.1, Power 0.8, α=0.05).