TDCS Promising for a Range of Illnesses

June 30, 2014 · Posted in Potential Treatments · Comment 

transcranial direct-current stimulationTranscranial direct current stimulation (tDCS) shows promise for a range of problems. In new research presented at the 2014 meeting of the Society of Biological Psychiatry, it was reported to be effective for improving cognition in bipolar disorder, alleviating depression, and reducing hallucinations.

How TDCS Works

At the meeting, researcher Marom Bikson discussed tDCS technology. The treatment can be delivered with a 12-volt battery. The anode directs current inward and is excitatory, while the cathode directs current outward and is inhibitory. The dendrites at the top of neurons under the anode are hyperpolarized by the tDCS, leading to relative depolarization of the cell soma, thus increasing excitation. TDCS, unlike repetitive transcranial magnetic stimulation (rTMS), which causes cells to fire, is only neuromodulatory, inducing minor changes in membrane polarization.

TDCS Improved Cognition in Bipolar Disorder

At the 2014 meeting of the American Psychiatric Association, Roberto Delle Chiaie et al. reported that two mA tDCS for 20 minutes for 15 days (anode over the left prefrontal cortex and cathode over the right cerebellum) improved immediate and delayed recall, trail making with a pointer, and motor coordination in 17 euthymic bipolar patients. This very promising result deserves further study and replication.

Antidepressant Effects of TDCS

At the 2014 meeting of the Society of Biological Psychiatry, Collen Loo reported that tDCS had positive effects in depressed patients compared to sham treatment. This complements a 2013 article by Brunoni et al. in JAMA Psychiatry that tDCS plus the selective serotonin reuptake inhibitor (SSRI) antidepressant sertraline (Zoloft) was more effective than either treatment alone.

TDCS for Treatment-Resistant Hallucinations

Jerome Brunelin et al. reported at the meeting that tDCS had positive effects in patients with schizophrenia who had hallucinations that resisted treatment. The positive electrode (anode) was placed over the left prefrontal cortex and the negative electrode (cathode) over the left temperoparietal area, where hallucinations are thought to originate. Stimulation was at two mA for 20 minutes, five days per week for two weeks. Effects lasted as long as 30 days and were associated with reduced functional connectivity of these brain regions.

Low frequency (1Hz) rTMS, which decreases neural activity, also improves refractory hallucinations when applied over the temperoparietal area, which is important for language. Placing the cathode over this area in tDCS is also inhibitory, so comparisons of rTMS with tDCS for suppressing hallucinations would be of great interest and importance.

Transcranial Direct Current Stimulation Plus Zoloft Has Better Antidepressant Effects Than Either Treatment Alone

January 29, 2014 · Posted in Potential Treatments · Comment 

transcranial direct-current stimulationTranscranial direct current stimulation (tDCS), in which a barely perceptible level of electrical current is applied directly from one side of a patient’s scalp to the other, is a promising treatment for patients with tought-to-treat depression. A 2013 study by Brunoni et al. in JAMA Psychiatry examined whether combined treatment using tDCS and the selective-serotonin reuptake inhibitor (SSRI) antidepressant sertraline (Zoloft) would be a safe and effective treatment for unipolar depression. The combination was better than either treatment alone and better than placebo.

The six-week study used what is called a 2×2 factorial design, in which 120 patients with unipolar depression received either 50 mg/day of sertraline or placebo and also received either real tDCS or a sham procedure. The tDCS was administered in twelve 30-minute sessions, one per day Monday through Friday during the first two weeks, followed by one every other week. TDCS consists of an anodal (positive) and cathodal (negative) current placed at particular positions on the head. This study used 2 microamps of anodal left/cathodal right prefrontal stimulation for the tDCS treatment.

While the combination of sertraline and tDCS was significantly better than all three other treatment options (sertraline plus sham procedure, placebo plus tDCS, and placebo plus sham procedure), sertraline by itself and tDCS by itself resulted in similar efficacies. However, TDCS by itself was also significantly better than placebo, while sertraline by itself was not.

Side effects among the different treatment options were similar, except those who received tDCS had more scalp redness. There were seven instances of patients developing mania or hypomania during the study, five of which occurred in the combined tDCS and sertraline treatment group, higher than the 1–2% rate that would be expected in a study of unipolar depression.

« Previous Page