a1 Núcleo de Neurociências, Centro de Ciências Biológicas e da Saúde, Universidade Presbiteriana Mackenzie, Sao Paulo, Brazil
a2 Department of Psychiatry, University of Sao Paulo, Sao Paulo, Brazil
a3 Department of Clinical Neurophysiology, Georg-August-University, Goettingen, Germany
a4 Center for Noninvasive Brain Stimulation, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, USA
Preliminary findings suggest that transcranial direct current stimulation (tDCS) can have antidepressant effects. We sought to test this further in a parallel-group, double-blind clinical trial with 40 patients with major depression, medication-free randomized into three groups of treatment: anodal tDCS of the left dorsolateral prefrontal cortex (active group – ‘DLPFC’); anodal tDCS of the occipital cortex (active control group – ‘occipital’) and sham tDCS (placebo control group – ‘sham’). tDCS was applied for 10 sessions during a 2-wk period. Mood was evaluated by a blinded rater using the Hamilton Depression Rating Scale (HDRS) and Beck Depression Inventory (BDI). The treatment was well tolerated with minimal side-effects that were distributed equally across all treatment groups. We found significantly larger reductions in depression scores after DLPFC tDCS [HDRS reduction of 40.4% (±25.8%)] compared to occipital [HDRS reduction of 21.3% (±12.9%)] and sham tDCS [HDRS reduction of 10.4% (±36.6%)]. The beneficial effects of tDCS in the DLPFC group persisted for 1 month after the end of treatment. Our findings support further investigation on the effects of this novel potential therapeutic approach – tDCS – for the treatment of major depression.
(Received December 11 2006)
(Reviewed February 09 2007)
(Revised April 03 2007)
(Accepted April 18 2007)
(Online publication June 11 2007)
c1 Address for correspondence: F. Fregni, M.D., Ph.D. or P. S. Boggio, M.Sc., Center for Noninvasive Brain Stimulation, Department of Neurology, Beth Israel Deaconess Medical Center, 330 Brookline Ave – KS 452, Boston, MA 02215, USA. Tel.: 617-667-5272 Fax: 617 975-5322 E-mail: firstname.lastname@example.org or email@example.com
* These authors contributed equally to this work.