Unilateral repetitive transcranial magnetic stimulation of the motor cortex does not affect cognition in patients with fibromyalgia

• Published in: Journal of psychiatric research 2013-01, Vol.47 (1), p.72-77
• Main Authors: Baudic, Sophie, Attal, Nadine, Mhalla, Alaa, Ciampi de Andrade, Daniel, Perrot, Serge, Bouhassira, Didier
• Format: Article
• Language: English
• Subjects: Biological and medical sciences; Chronic pain; Cognition; Cognition Disorders - physiopathology; Cognition Disorders - therapy; Cortex; Diseases of the osteoarticular system; Double-Blind Method; Episodic memory; Evoked Potentials, Motor - physiology; Fibromyalgia; Fibromyalgia - physiopathology; Fibromyalgia - therapy; Humans; Medical sciences; Middle Aged; Miscellaneous. Osteoarticular involvement in other diseases; Motor cortex; Motor Cortex - physiopathology; Neuropsychological Tests; Neuropsychology; Psychiatry; Psychology. Psychoanalysis. Psychiatry; Psychopathology. Psychiatry; rTMS; Stimulation; Transcranial magnetic stimulation; Transcranial Magnetic Stimulation - adverse effects; Transcranial Magnetic Stimulation - instrumentation; Transcranial Magnetic Stimulation - methods; Treatment Outcome
• ISSN: 0022-3956; 1879-1379
• DOI: 10.1016/j.jpsychires.2012.09.003

Abstract Repetitive transcranial magnetic stimulation (rTMS) induces changes in neuronal activity that may affect cognition. We assessed cognitive functions, in patients with fibromyalgia participating in a sham-controlled randomized trial of rTMS for pain management. We randomly assigned 38 non depressed fibromyalgia patients (American College of Rheumatology criteria) to the active ( n  = 20) and sham ( n  = 18) rTMS treatment groups, in a double-blind manner. rTMS was applied to the left primary motor cortex (10 Hz at 80% of rest motor threshold). Neuropsychological tests were performed immediately before stimulation, to evaluate episodic memory, selective and divided attention and executive functions at baseline, week 3 (after 7 rTMS sessions) and week 11 (after 11 rTMS sessions). The actively treated and sham-treated groups were similar in terms of clinical and neuropsychological variables at baseline. No difference in overall neuropsychological performance with respect to baseline was found between these two groups, but a significant improvement over time was observed in the rTMS group, for several measurements of attention/executive function (the Symbol Digit Modalities Test and the Stroop Color Word Test). Unilateral rTMS of the motor cortex over a three-month period did not modify cognitive functions in patients with chronic pain. rTMS may have mild beneficial cognitive effects, but confirmation is required in larger groups of patients.