Determinants of representational and behavioral hyperactivity in patients with fibromyalgia syndrome.

Fibromyalgia is associated with a premorbid hyperactivity. This study examines how contextual and personality factors contribute to premorbid hyperactivity. A total of 45 patients completed questionnaires. The results show that the number of children and the basic bodily needs neglect (and their interaction) explain nearly 50 percent of the variance of hyperactivity. The neglect toward bodily needs completely mediates the relation between self-oriented perfectionism and hyperactivity. This study suggests that hyperactivity itself would not have a pathological value, but that the neglect of basic bodily needs would represent a vulnerability factor in a hyperactive premorbid lifestyle in fibromyalgia patients.

The contribution of recollection and familiarity to recognition memory performance in chronic pain patients.

This study examines the selective impact of chronic pain on memory functioning in a recognition task. Thirty chronic pain patients and 30 healthy control subjects performed a yes-no word recognition test. The contribution of recollection and familiarity to both groups' performance was compared by means of the Remember/Know (R/K) procedure, which distinguishes recognition based on the recollection of the encoding episode (R responses) and recognition accompanied by a feeling of familiarity (K responses). Chronic pain patients showed a decrease in recollection together with an increase in familiarity: indeed, they reported less R and more K responses than control subjects. This pattern of performance was not related to the overall recognition ability. These findings are consistent with the hypothesis of the attentional cost of chronic pain, suggesting a selective impact of chronic pain on the most attention-demanding cognitive processes, such as recollection. This study emphasises the relevance of specific procedures distinguishing the underlying components of memory functioning rather than solely global indicators.

Development and validation of the Neuropathic Pain Symptom Inventory.

This study describes the development and validation of the Neuropathic Pain Symptom Inventory (NPSI), a new self-questionnaire specifically designed to evaluate the different symptoms of neuropathic pain. Following a development phase and a pilot study, we generated a list of descriptors reflecting spontaneous ongoing or paroxysmal pain, evoked pain (i.e. mechanical and thermal allodynia/hyperalgesia) and dysesthesia/paresthesia. Each of these items was quantified on a (0-10) numerical scale. The validation procedure was performed in 176 consecutive patients with neuropathic pain of peripheral (n = 120) or central (n = 56) origin, recruited in five pain centers in France and Belgium. It included: (i) assessment of the test-retest reliability of each item, (ii) determination of the factorial structure of the questionnaire and analysis of convergent and divergent validities (i.e. construct validity), and (iii) evaluation of the ability of the NPSI to detect the effects of treatment (i.e. sensitivity to change). The final version of the NPSI includes 10 descriptors (plus two temporal items) that allow discrimination and quantification of five distinct clinically relevant dimensions of neuropathic pain syndromes and that are sensitive to treatment. The psychometric properties of the NPSI suggest that it might be used to characterize subgroups of neuropathic pain patients and verify whether they respond differentially to various pharmacological agents or other therapeutic interventions.

Controlled processes and automaticity in memory functioning in fibromyalgia patients: relation with emotional distress and hypervigilance.

Evidence exists that chronic pain partially consumes the limited attentional resources, with the consequence that controlled processes sustaining cognitive tasks are affected and that automatic processes are preserved. Fibromyalgia syndrome is consistently rated as more severe than other chronic painful conditions. It is assumed here that fibromyalgia is more attention-demanding, leading to a more pronounced decrease of the controlled processes in comparison with other chronic painful conditions. In this perspective, Study 1 compares fibromyalgia patients, patients with localized pain and healthy subjects in a procedure separately estimating the within-task contributions of controlled and automatic processes in a cued recall task. As predicted, controlled processes are more strongly affected in fibromyalgia patients related to the group with localized pain. Unexpectedly, contribution of automatic processes is increased in fibromyalgia. Study 2 replicates these results and reveals that memory functioning in fibromyalgia patients is related to their painful condition as a whole rather than to any particular patient's characteristics.

Conscious and automatic uses of memory in chronic pain patients.

Memory deficits in chronic pain patients are frequently observed. The objective of this study was to explore memory performances of chronic pain patients by using the Process Dissociation Procedure developed by Jacoby (J. Mem. Lang. 30 (1991) 513). This procedure permits to separate the contribution of controlled processes from automatic processes operating within a memory task. The results show a significant decrease of controlled processes in chronic pain patients. Furthermore for both groups, automatic processes contribute in a similar extent to the memory performance. The estimates of controlled processes in the chronic pain patients are significantly related to the fear of pain and catastrophic beliefs. This is interpreted as a sign of interference between the attention consumed by pain experience (namely fear related to pain) and the attention to be allocated to the memory task.