Brain Stimulation in Psychiatric Treatment

Ever since man found ways to control electrical and magnetic fields, these skills have been part of medical experimentation (1, 2). The French revolutionary Jean-Paul Marat published a treatise on medical uses of electricity in 1783 (3). Reports that electric shocks to the head of mentally ill patients elicited facial grimacing and prolonged insomnia that ameliorated psychoses and melancholia appeared in 1804 (4). Experiments with static electricity were showpieces for Benjamin Franklin in French drawing rooms in the late 18th century (5). Recently, the new technologies of transcranial magnetic stimulation (and its offshoot, magnetic seizure therapy), deep brain stimulation, and vagus nerve stimulation have captured psychiatric attention.

This paperback describes each technique and the results of clinical trials in psychiatric patients. The authors conclude,

These nonseizure methods are offered as replacements for ECT by researchers who seek “a means of reducing the cognitive side effects of ECT…[because] its use is limited by cognitive and other side effects” (p. 69). Other nonseizure methods, such as sham ECT, electrosleep, EEG alpha enhancement, low-voltage direct-current bifrontal stimulation, isoflurane anesthesia-induced EEG silence, and light therapy, were proffered as ECT replacements, and each has been found wanting. These new methods are also not equal to the challenge.

A risk of transcranial magnetic stimulation is eliciting of a grand mal seizure. After the failure to demonstrate its psychiatric benefits, the researchers now exploit this risk as a clinical technique. They offer magnetically induced grand mal seizures, hoping that the benefits will match those of ECT with lesser effects on memory. This hope, however, is inconsistent with the 70 years of experimentation with convulsive therapy. Seizures have been induced with intramuscular camphor or insulin, intravenous pentylenetetrazol, the inhalant flurothyl, and electrically. When full grand mal seizures are induced by any method, the behavioral effects are demonstrable, as are accompanying transient memory effects. An extensive experience with the asymmetric and partial seizures induced with unilateral electrode placement found seizures with lesser cognitive effects to have lesser clinical benefits (6). Among stimulation techniques, ECT dominates clinical practice today, not for any specific benefit or lesser risk associated with electricity but for ease of use, least expense, and least discomfort to patients. Magnetic seizure therapy may, in time, emulate ECT, but it is improbable that it will be as easy and as inexpensive as electrical inductions.

Transcranial magnetic stimulation, deep brain stimulation, and magnetic seizure therapy are not yet approved for clinical use by the U.S. Food and Drug Administration. Vagus nerve stimulation is approved for intractable epilepsy. It requires the surgical implantation of a stimulator in the chest wall with leads that snake up to the vagus nerve in the neck. Stimulation impairs speech, and the risks of surgery are not to be passed over lightly. The Wall Street investors and their consultant researchers who are supporting this treatment should be required to demonstrate a remarkable efficacy in specifically defined populations before it is approved for clinical use in psychiatry. The mentally ill may not be able to properly make fully informed judgments of the benefits, risks, and expense of this procedure, which, once implanted, requires another surgical procedure for its removal.

Four years ago, the American Psychiatric Press summarized the first experiences with transcranial magnetic stimulation (7). The publisher’s current report offers no new evidence of clinical utility. The reviews in this volume offer little hope that these brain stimulation techniques are replacements for ECT. Readers will find little reason to alter their clinical practice. These experiments are not based on a theory of brain and behavior but are offered for the same reason that explorers climb Mount Everest. In this context, it is useful to recall that convulsive therapy was developed on the basis of neuroscience data and not as an empirical adventure (8).