Can Electrically Stimulating The Brain Improve Mental Health?

04/03/2010 05:12 am ET | Updated Nov 17, 2011

So many people think that ECT (electroconvulsive therapy, sometimes erroneously called "shock therapy") is the only way to apply electrical stimulation to the brain as a treatment. Not so. In fact, there are a variety of proven and promising electrical (or magnetic) techniques that affect the brain -- from those with virtually no side effects, nor an invasive procedure, to those that are surgical in nature.

Why consider applying a current to the brain? Primarily to offer an alternative to psychopharmacological (medication) treatments. We need different yet safe and effective ways of improving mood and anxiety disorders or reducing insomnia and stress.

Medications affect levels of neurotransmitters, or chemicals such as serotonin, norepinephrine or dopamine, naturally present in the brain (within or between nerve cells) known to affect how we feel, think and act. Electrical stimulation and magnetic fields induce currents that change the way that brain cells, called neurons, fire. In other words, medications work on molecules and brain stimulation works on cells. Brain stimulation, notably, has no known interaction or effect on medications a person may be taking, unlike most other treatments we have. Neuroscientists and psychiatrists have been searching for alternatives to pills for centuries because too many individuals do not fully respond or have side effects and medical complications from the medications so far developed.

Interest in electrically stimulating the brain dates back to the 1930s when Italian scientists developed a means of inducing a brain seizure by applying an intense electric current to the scalp - which we now call ECT. While ECT remains an important treatment today for those individuals whose condition, especially severe depression, does not respond to medication and therapy -- it does require anaesthesia, produces at least short-term memory problems, frightens many people, is costly and is often transitory in its effects. Hence, the search for alternative means of improving brain functioning in people with psychiatric disorders.

Remarkably, over 60 years ago (1949) scientists in the (then) Soviet Union began applying a very low voltage alternating current to stimulate the brain, CES or cranial electrical stimulation, which they called "electrosleep" to treat insomnia (cranial refers to the skull or cranium, where the electrical leads are placed and the scalp stimulated). This treatment does not deliver any where near the electrical current needed to induce seizures. The repertoire of brain stimulation techniques grew in the mid-1980s when magnetic fields were applied around the cranium to stimulate the brain, a technique knows as TMS, or transcranial magnetic stimulation. More recently, brain stimulation has been done surgically by deep brain stimulation (DBS) and vagal nerve stimulation (VNS), which were first used for neurological conditions such as epilepsy and Parkinson's disease, then adapted for psychiatric conditions. Of all the brain stimulation procedures available recent interest has been greatest about CES and TMS.

CES, cranial electrical stimulation, applies a weak, alternating current to the scalp usually by leads placed on a person's temples or earlobes. CES has had FDA approval for over 30 years as a device (grandfathered-in, or approved without specific study) to treat depression, anxiety, insomnia and stress; it has also been used to aid in long term abstinence in people with alcohol and drug dependence. The current is of micro-voltage (ECT has 1000-fold more current), can hardly be felt, has little or no side-effects, or evident harm. While there are many testimonials to its benefits we lack rigorous study of its therapeutic effectiveness. CES devices can be purchased over the internet and a variety of companies will sell you one, with a medical prescription, which you can apply to yourself at home. CES is quite safe but its benefits remain to be scientifically established: we have promise, but not proof.

TMS, transcranial magnetic stimulation also known as rTMS, delivers alternating magnetic fields to the scalp that induce electrical currents in the brain cortex, or outer layers of the brain. The electrical currents are about 100-200 times more powerful than CES but do not require anesthesia; TMS is not meant to induce seizure (though this is a low risk of the procedure). The electric current induced by the magnetic field produces immediate and very brief nerve cell activity, or firing of brain cells. TMS recently achieved FDA approval for treatment resistant major depression but must be prescribed and administered by a professional; insurance coverage for this FDA approved treatment is spotty. TMS is proven to work and thus represents an important choice in the treatment of major depression for individuals who are not responsive to properly selected and administered medication and therapy.

Mental illnesses are highly prevalent, cause great suffering in those affected and their loved ones, and can produce disability and heavy financial burden to families and society. As a result, we are on a continuous quest to discover new, safe, effective and acceptable treatments for people with illnesses such as depression, anxiety disorders, substance use disorders, and psychotic illnesses (such as schizophrenia and bipolar disorder). In addition, safe and affordable interventions for distressing symptoms like insomnia, stress, and low or anxious mood that do not reach the proportions of a mental disorder are needed. While medications tend to get the most press when it comes to treatments for mental conditions they are but one approach.

We know that psychotherapy works, especially structured forms of therapy like cognitive-behavioral therapy, interpersonal therapy and desensitization techniques; we know that alternative forms of treatment like acupuncture, meditation, yoga, homeopathy, and forms of eastern body work (shiatsu and sugi massage) can be helpful in disease states and everyday suffering; and we have means of brain stimulation that work or show promise.

Knowing what works for whom at what point in the course of illness is the science and art of psychiatric medicine. A diverse set of therapeutics is essential since no one treatment works for everyone, nor meets the important preferences that individuals bring to the therapeutic encounter. The more diverse the alternatives the better the chance that each person will find something that relieves their suffering and enables the functioning we all want to have a life lived with others and of contribution.

The opinions expressed herein are solely my own as a psychiatrist and public health advocate.
Lloyd I Sederer, MD