A type of brain stimulation caused by a mild electric current
that appears to have minimal negative side effects is showing
promise as a potential treatment for major depression, according
to several studies. The experimental therapy, known as
transcranial direct current stimulation, or tDCS, involves a
low-level charge about one-400th of that used in electroshock
treatment. Unlike electroshock (also called electroconvulsive
therapy or ECT), which is administered for a few seconds to
patients under anesthesia, tDCS is given for 20 to 30 minutes
continuously while patients are conscious. While doctors do not
see it replacing electroshock, considered the most effective
approach for major depression that has been treatment-resistant
and requires urgent attention, tDCS does not appear to cause
memory loss as electroshock can. Because it is inexpensive and
easily administered, scientists say it might become an
alternative or additional treatment for people whose depression
is not completely helped by medication. “