 Will be included women aged between 18 and 65 years, chronic pain fibromyalgia according to the criteria of the American College of Rheumatology, pain unresponsive to analgesics such as paracetamol, acetylsalicylic acid, ibuprofen, Carisoprodol, Zanaflex Tizanidine and Codeine. And give informed consent to participate after initial evaluation. Primary outcome is to evaluate the effect of treatment with home-base tDCS in patients with fibromyalgia. Secondary outcomes are: compare the effect of active home-based tDCS and sham in cortical neurophysiological processes and subcortical to stimulation with TMS and standardized noxious stimuli with and without concomitant conditioned Pain Modulation CPM in pain threshold outcomes to the test mechanical pressure, heat-algesic stimulus, cortical excitability parameters evoked rest motor MEP MEP enough to evoke amplitude of 1 mV peak to peak, silent period SP, motor threshold MT, variation in blood volume and oxygenation cortical motor area oxy-hemoglobin concentrations Hbo deoxy-hemoglobin HBr optically functional neuroimaging NIRS and variation in the frequency of alpha and beta waves of motor area stimulated by tDCS assessed by electroencephalogram EEG. In surrogate outcome, the investigators will compare the effect of active home-sham tDCS the tDCS in pain levels and functional capacity, catastrophic thinking, bookmark levels of neurotrophic activity BDNF and astrocytic S100 beta. 