Repetitive Thinking in Fibromyalgia (PRFM-3)

Some fibromyalgia patients may use inappropriate emotional regulation strategies to respond to pain. Rumination could be one of this inefficient regulation strategies. The investigators believe that the use of rumination strategies to respond to the discomfort of daily physical activity would maintain and aggravate a negative emotional state after the effort. Distraction would be a more effective strategy to cope with pain. From this data, the investigators want to explore the causal link between rumination and negative affectivity after physical activity in fibromyalgia using an experimental design.

Fibromyalgia is a disorder characterized by widespread musculoskeletal pain accompanied by fatigue, sleep, memory and mood issues. As with any condition of chronic pain, psychological mechanisms can help maintain discomfort and pain. These mechanisms may hinder the recovery of physical activity. Some patients may use cognitive strategies of emotional regulation that are ineffective to cope with pain and discomfort of everyday activities, such as rumination. The literature suggests that this process is linked to the physical and psychological difficulties of fibromyalgia. However, no study has revealed a causal link between rumination and negative affectivity in a context of physical activity in this population. The investigators want to test this hypothesis by directly manipulating the style of information processing following a relevant activity for these patients: climbing steps. In one group the investigators will induce rumination right after climbing the steps. In the other group the investigators will induce distraction. Patient with Fibromyalgia will be recruited at the Pain Center of CHU-Amiens. Patients will complete different scales before to climb steps and after experimental induction. The investigators hypothesize that Patients using a rumination strategy after an uncomfortable physical activity will experience a greater subjective discomfort than patients using a distraction strategy.

The patients will receive rumination induction. Rumination induction will follow a relevant activity for our patients: climbing steps. Rumination induction will be done right after climbing the steps.

Distraction will follow a relevant activity for our patients: climbing steps. Distraction induction will be done right after climbing the steps.

The induction method is based on specific instructions given to participants on how to focus on different elements of their experience. For example, they will be led, in the rumination condition, to reflect on the causes, meanings and consequences of the amount of tension they feel in their muscles.

The induction method is based on specific instructions given to participants on how to focus on different elements of their experience. In the distraction condition they will, for example, imagine a ship crossing the Atlantic.

The PANAS Scale or Positive and Negative Affect Schedule (PANAS) is a self-report questionnaire. The list is split up into two segments, or mood scales. One scale measures a person's positive emotion and the other scale measures the negative. Each segment has ten terms, which can be rated on a scale of 1 to 5 to indicate the extent to which the respondent agrees that this applies to him.Characteristic of this test is the fact that it can be completed in 10 minutes. High score is associated with stress and anxiety. small score is associated with calm.

The pain VAS is a unidimensional measure of pain intensity, which has been widely used in diverse adult populations, including those with rheumatic diseases. Visual analogue scales (VAS) are 10-cm lines anchored at the ends by words that define the bounds of various pain dimensions. The patient is asked to place a vertical mark on the scale to indicate the level of intensity of his or her pain, anxiety, depression, etc. 0 would mean "no pain" and 10 would mean "worst possible pain."

Inclusion Criteria: Adults Patients Free and informed consent signed. French native speaker, writer and reader. according 1990 American College of Rheumatology criteria : Patients with diffuse pain for more than three months and with digital palpation pain on more than 11 insertion points. Exclusion Criteria: minor patients Adult major under administrative protection Patient with severe psychosis or depression or severe anxiety or impulsivity as assessed by the clinician