Depression is a common psychological disorder with a prevalence rate of 3% to 8%. Clinically, it is mainly characterized by significant and persistent depressed mood with persistent fatigue and loss of energy, insomnia, anxiety, irritability, appetite and weight changes, and in severe cases, even hallucinations, delusions and suicide. Depression is a chronic disease with a high disability rate, and its incidence and suicide rate are very high. The World Health Organization predicts that depression will become one of the three major diseases that will endanger human health in the 21st century, along with cancer and AIDS. The exact pathogenesis of depression is still unclear, but it is generally believed to be the result of the interaction of biological, psychological and social factors. At present, the main methods of treating depressed patients are medication and psychotherapy. The efficiency of existing antidepressants and various psychological treatments for depression is generally around 60% to 80%. Thus, there are always some patients who are not effective in treatment, and these patients may be “refractory depression” patients. Refractory depression is generally defined as depression that has not been treated with adequate amounts and courses of at least two antidepressants with different mechanisms of action. Although there are still concerns about electroconvulsive therapy (ECT), it remains one of the best options for major depressive disorder and refractory depression. ECT has a rapid onset of action and is particularly indicated for patients at serious risk of suicide. Nevertheless, there are many depressed patients who respond poorly to ECT or whose effects do not last, and there are many contraindications and adverse effects to ECT. In order to treat these patients with refractory depression, it is imperative to develop new treatment methods, and the DeepBrainStimulation (DBS) method, in which a pacemaker is placed in the brain to continuously release pulsed electrical currents, is one of the new methods currently under investigation. Deep brain stimulation with a pacemaker is a new, minimally invasive surgical procedure used in functional neurosurgery to treat Parkinson’s disease and other idiopathic movement disorders. The method uses a very small electrode piece that is placed in a designated area of the brain with the aid of computerized 3D imaging and then connected to a small pulse generator that is placed under the patient’s collarbone. This is very similar to a cardiovascular pacemaker. The pulse generator continuously generates a very small electrical current so that patients with Parkinson’s disease can use a special magnet to adjust the amount of stimulation when a tremor occurs, just like a pacemaker, to control the symptoms of the tremor. The main advantage of deep brain stimulation is that it does not damage normal brain tissue and is a reversible procedure, so that the stimulator can even be removed if there are adverse side effects. In a recent study, Dr. Helen and others from Emory University School of Medicine in Atlanta, GA, used deep brain stimulation to treat patients with refractory depression with more satisfactory results, which have been published in a recent issue of the world-renowned neurology journal Neuron. The team rigorously screened six patients who were not responding to current antidepressant medications, psychotherapy and ECT. Each of the six patients was subjected to deep brain stimulation, in which pacemakers – microelectrodes – were implanted in the white matter of the brain adjacent to the subgenus of the cingulate gyrus, where high-frequency, low-voltage pulsed currents were continuously emitted. Immediately after implantation, all patients felt relief from their depression, and six months after implantation, clinical symptoms had almost completely disappeared in three patients. Various studies have now shown that depression is associated with abnormal brain function in areas of the patient’s brain such as the prefrontal cortex, limbic system and adjacent subcortical structures. The study, using positron emission computed tomography (PET), also found changes in glucose metabolism in the brains of the six patients after treatment, and a return to normal levels of local brain function in the prefrontal-cingulate cortex, a part of the brain closely related to human mood. Therefore, the researchers concluded that the use of electrical stimulation in a pacemaker to block pathological firing in local circuits of the limbic-cortical system could be effective in relieving the symptoms of these patients with refractory depression. Pacemakers have been implanted in the human body for many years to treat diseases. Pacemakers are actually electrodes implanted in the heart to replace the firing work of cardiac muscle cells. Since the world’s first pacemaker was implanted in 1950, the procedure has been performed on millions of people worldwide. Pacemakers, which are now widely used to treat cardiac arrhythmias, can even automatically adjust the pacemaker to the patient’s physiological needs according to the patient’s activity (e.g., exercise), greatly improving the patient’s quality of life. However, the human brain is very complex in structure and function, and the neuroelectrical activity of the brain is much more complex than the electrical activity of the heart, and there are still many uncharted territories. The mechanism by which pacemakers relieve depression symptoms is not well understood either. Further research is needed to confirm whether brain pacemakers will be as safe and effective as pacemakers in modulating brain electrical activity in the treatment of patients with refractory depression. Nevertheless, deep brain stimulation is at least a new therapeutic opportunity for refractory depression.