A controlled trial of daily left prefrontal cortex TMS for treating depression.

BACKGROUND: Transcranial magnetic stimulation (TMS) is a new technology for noninvasively stimulating the brain. Several studies have suggested that daily stimulation of the left prefrontal cortex with TMS for 2 weeks has probable antidepressant effects. We conducted a parallel-design, double-masked, sham-controlled study to address whether 2 weeks of daily TMS over the left prefrontal cortex has antidepressant activity greater than sham. METHODS: Thirty medication-free adult outpatients with nonpsychotic, major depressive (n = 21) or bipolar (n = 9) (depressed phase) disorder who were in a current major depression (Hamilton Rating Scale for Depression [HRSD] 21-item score of >18) were treated each weekday for 2 weeks. Subjects were randomly assigned to receive either daily active (20 subjects) or sham (10 subjects) stimulation. Additionally, the 20 active subjects were equally divided between slower (5 Hz) and faster (20 Hz) frequency treatment. Antidepressant response was defined as greater than a 50% improvement in the baseline HRSD. RESULTS: Active TMS resulted in significantly more responders (9/20) than did sham (0/10) (chi(2) = 6.42, p <.01). The number of responders did not differ significantly between the two active cells (3/10 faster and 6/10 slower). Expressed as a percent change from baseline, active TMS subjects had significantly greater improvement on the Beck Depression Inventory as well as the Hamilton Anxiety Rating Scale than did those who received sham. CONCLUSIONS: Daily left prefrontal TMS for 2 weeks significantly reduced depression symptoms greater than did sham. The two forms of active TMS treatment did not differ significantly.

Vagus nerve stimulation: a new tool for brain research and therapy.

Biological psychiatry has a long history of using somatic therapies to treat neuropsychiatric illnesses and to understand brain function. These methods have included neurosurgery, electroconvulsive therapy, and, most recently, transcranial magnetic stimulation. Fourteen years ago researchers discovered that intermittent electrical stimulation of the vagus nerve produces inhibition of neural processes, which can alter brain electrical activity and terminate seizures in dogs. Since then, approximately 6000 people worldwide have received vagus nerve stimulation for treatment-resistant epilepsy. We review the neurobiology and anatomy of the vagus nerve and provide an overview of the vagus nerve stimulation technique. We also describe the safety and potential utility of vagus nerve stimulation as a neuroscience research tool and as a putative treatment for psychiatric conditions. Vagus nerve stimulation appears to be a promising new somatic intervention that may improve our understanding of brain function and has promise in the treatment of neuropsychiatric disorders.

Vagus nerve stimulation. A potential therapy for resistant depression?

VNS builds on a long history of investigating the relationship of autonomic signals to limbic and cortical function and is one of the newest methods to physically alter brain function. VNS is a clinically useful anticonvulsant therapy in treatment resistant patients with epilepsy, and pilot data suggest that it has potential as an antidepressant therapy. The known anatomic projections of the vagus nerve suggest that VNS also might have other neuropsychiatric applications. Additional research is needed to clarify the mechanisms of action of VNS and the potential clinical utility of this intriguing new somatic portal into the CNS.