Neurosurgical approaches to therapeutic brain stimulation for treatment-resistant depression

During the 1940s and 1950s, psychosurgery was used for the treatment of severe mental disorders but was associated with significant complications. These problems and the advent of psychotropic drugs led to a decline in the use of psychosurgery. Neuroanatomical and brain imaging studies have revealed distinct brain regions and the pathways that connect them, which may underlie depression and other mental disorders. On the basis of this knowledge, modern stereotactic neurosurgical methods have been used to implant electrodes in the brain to provide therapeutic stimulation. Electrical stimulation by these electrodes with pacemaker-like devices can be used to modulate brain function by stimulating or inhibiting the activity of specific brain regions, without causing permanent or destructive lesions that cannot be reversed. Deep brain stimulation and cortical brain stimulation are two such neurosurgical approaches to therapeutic brain stimulation for treatment-resistant depression.