How cranioelectrotherapy stimulation works
Cranioelectrotherapy stimulation (CES), also called transcranial direct current stimulation (tDCS) or microcurrent electrical stimulation, is based on the application of extremely weak electrical current to the head and neck to treat anxiety, depressed mood, insomnia, and substance abuse. The mechanism of action may involve stimulation of endorphin release and induction of frequency changes in the frequency of brain waves that, in turn, reduce the severity of emotional and cognitive symptoms. This blog briefly reviews findings for anxiety, dementia, substance abuse and insomnia. A future blog post will review the evidence for microcurrent electrical stimulation for treating depressed mood.
CES for treating anxiety
A meta-analysis of controlled trials comparing CES with a sham treatment found that generalized anxiety improved in seven of eight studies, and the magnitude of improvement reached statistical significance in four of these. A review of 34 sham-controlled trials concluded that regular CES treatments resulted in short-term symptomatic relief of generalized anxiety through direct effects on autonomic brain centers. Individuals diagnosed with one or more phobias reported significant reductions in the level of anxiety when exposure to the phobic stimulus was followed by 30 minutes of CES treatment.
CES for treating dementia
Daily application of weak electrical current to the neck or the head may stimulate global brain activity, resulting in beneficial changes in the activity of neurotransmitters implicated in dementia. A meta-analysis of three studies on CES in patients with dementia found evidence of significant but transient improvements in word recall, face recognition, and motivation immediately following treatment that were not sustained at 6-week follow-up.
CES for alcohol and drug abuse
CES is used to lessen symptoms of alcohol and drug withdrawal. The postulated mechanism of action involves stimulation of release of endorphins, enkephalins, and other endogenous opioid peptides and may prove to be similar to the mechanism underlying electroacupuncture. In a 4-week RCT (20 subjects), depressed alcoholics were randomized to receive 20 CES treatments at 70 to 80 Hz, 4 to 7 milli-amps, versus sham treatments. Patients who received CES treatments experienced significantly reduced anxiety by the end of the study. Findings of a sham-controlled study (60 subjects) on hospitalized alcohol or polysubstance abusers suggested that daily 30-minute CES treatments significantly improved cognitive functioning and reduced measures of stress and anxiety during the acute phases of withdrawal in this population. In a 7-year prospective study of CES in the treatment of alcohol, drug, and nicotine addiction, acute and chronic withdrawal symptoms were diminished, normal sleep patterns were restored more rapidly, and more patients remained addiction-free following regular CES treatments compared to conventional psychopharmacological management. The discrepancy between largely positive outcomes from studies on CES and frequent negative findings on electroacupuncture in detoxification may be partly attributable to sub-optimal current or frequency settings in electroacupuncture protocols investigated for this clinical application.
CES for insomnia
CES is widely used to treat insomnia. However, findings of sham-controlled studies are inconsistent. Whereas some studies showed no beneficial effects of CES in insomnia, others reported sustained improvements in the timing of sleep onset and total sleep duration. Disparate findings on the therapeutic benefits of CES in insomnia may be related to differences in equipment, protocols, and duration and timing of treatment.
Transient mild adverse effects of microcurrent electrical brain stimulation are sometimes reported.