When medications alone are not effective enough to relieve the symptoms of depression or when people are unable to take medications due to conditions such as pregnancy, non-pharmaceutical medical therapies may be of help. These therapies include electroconvulsive therapy (ECT), light therapy, vagal nerve stimulation (VNS), and several other currently experimental therapies including transcranial magnetic stimulation (TMS), and deep brain stimulation.
Electroconvulsive Therapy (ECT)
Electroconvulsive Therapy, or ECT, is perhaps the most successful non-pharmaceutical medical therapy for depression. Often referred to as "shock therapy", ECT involves passing an electric current through the brain to create an artificial seizure. ECT is typically used for people with severe, treatment-resistant depressions and/or other people requiring non-pharmaceutical treatment of depression.
The ECT procedure takes about 10 or 15 minutes, with an additional 30-45 minutes for preparation and recovery, and can be performed either during a hospital stay or as an outpatient procedure. In either case, ECT requires brief general anesthesia (i.e., the person is asleep during the procedure). Prior to the procedure, patients are given muscle relaxants to prevent damage from convulsions, which occur during the seizure. An electrode (or electrodes) is placed on the side or the front of the person's forehead, and a short, controlled electrical current is passed through the brain.
Most patients receive 6 to 12 ECT treatments over the course of several weeks. Usually, treatment is administered two to three times a week until symptoms improve. Then, maintenance treatments will be administered at less frequent intervals. Though the procedure has the side effect of causing temporary short term-memory loss and concentration problems, it can work wonders when other treatments fail.
Historically, ECT was thought of as a barbaric, inhumane treatment. This is not at all the case today. Today's ECT technique is well-researched and regulated, quite safe, and provides very fast relief from forms of depression that will not otherwise respond to treatment. Furthermore, because there are no systemic (body) effects, ECT may be the safest treatment option for pregnant women or nursing mothers suffering from depression.
It is not clear exactly how ECT helps people with depression, but many neurochemical and neuronal aspects of brain functioning are altered during and after seizure activity. It is thought that when ECT is administered on a regular basis, these changes build upon one another, somehow reducing depression. In addition, as mentioned before in the section on neuroplasticity, ECT increases neuronal growth, which may lead to relief from depressive symptoms.
Light Therapy (Phototherapy)
Phototherapy involves controlled exposure to intense light under specified conditions. This therapy is most effective for people who suffer from seasonal affective disorder (SAD), a type of depression discussed previously that seems related to seasonal variations in sunlight. It is not entirely clear how phototherapy exerts its antidepressant effects; but researchers think that the light entering the eyes influences the hypothalamus, possibly via altered melatonin production (melatonin, a hormone product of the brain's pineal gland, is built out of serotonin), which in turn affects circadian and seasonal rhythms. Phototherapy is an inexpensive technique that can be done at home or at the office. There are no major side effects associated with its use.
Phototherapy sessions require a specialized light box with fluorescent bulbs and a diffusing screen. The light produced by the box is comparable to outdoor light just after sunrise or just before sunset - an intensity that is at least five times greater than ordinary indoor light. During a session, a person sits near a light box placed on a table. The person keeps their eyes open, but does not look directly at the light (i.e., you can read during the session). Researchers recommend phototherapy sessions lasting between 15 minutes and two hours, once a day, in the morning.
Recent research suggests that naturalistic dawn simulation and high-density negative air ionization delivered during the final hours of sleep may be effective alternatives to light therapy for people who suffer from SAD.
Vagal Nerve Stimulation (VNS)
The vagus nerve emerges from the base of the brain and travels down the neck into the chest and abdomen. This long nerve regulates a number of vital bodily functions such as digestion and heart function. In addition, the vagus nerve seems to play a role in regulating mood. Recently, the Food and Drug Administration approved vagal nerve stimulation or VNS for treating depressed individuals who have not responded to other therapies.
Stimulation of the vagus nerve is achieved by surgically implanting a small electrical pulse generator the size of a pocket watch in the upper-left side of the chest. Tiny wires, which transmit intermittent electrical pulses, are routed under the skin and up to the neck, where they wrap around the vagus nerve. Once the pulse generator is in place, the electrical pulses must be monitored and modified periodically by a neurologist in his or her office. This doctor controls how long pulses last and how frequently pulses are sent to the vagus nerve, depending on a person's response to therapy. The most common side effects of VNS include hoarseness and cough during stimulation. Although this treatment is effective, it is not instant. VNS takes several months to impact depressive symptoms.
Transcranial Magnetic Stimulation (TMS)
Currently, Transcranial Magnetic Stimulation or TMS is considered an experimental treatment, but this therapy appears to show great promise for helping people overcome depression. In TMS, a medical device is used to create a strong magnetic pulse that passes through the scalp and skull, stimulating neurons within the brain. TMS is usually administered in an outpatient setting (not in a hospital) and takes about 20 to 30 minutes. The patient is awake and alert during the procedure. In current experimental protocols, TMS is most effective in treating depression when administered once daily for two or more weeks.
TSM is somewhat similar to ECT in that the brain is stimulated with both techniques. However, ECT requires the passage of electrical current through the brain, while TMS involves the passage of magnetic waves through the brain.
TMS does not interfere with people's memory or concentration in the way that ECT does. However, the TMS procedure does on occasion cause a seizure to occur. Apart from the seizure risk, there are no significant side effects associated with the procedure. Treatment-resistant depression has been shown to improve with TMS.
Deep Brain Stimulation (DBS)
As mentioned previously, deep brain stimulation (DBS) is an experimental surgical treatment involving the implantation of a medical device that sends electrical impulses to specific parts of the brain. DBS has been approved for treating tremor (a disease where parts of the body, usually the hands, shake when someone is intentionally moving) dystonia (a disorder where muscle contractions cause twisting and repetitive movements or abnormal postures) and Parkinson's Disease. DBS has also shown some promise in helping people with treatment-resistant depression.
The pacemaker or stimulator that controls DBS is placed in specific areas of a person's brain (mapped out ahead of time using imaging technology such as a CT scan or MRI) during a surgical procedure where the patient is anesthetized (i.e., feels no pain), but awake. The device is then calibrated to provide optimal amounts of stimulation for each person. After approximately 3 to 5 years, the brain pacemaker must be replaced, because the batteries wear out across time.
In individuals with treatment resistant depression, the pacemaker is placed in the subgenual cingulate region (SCR or Brodmann's area 25) or the nucleus accumbens (a part of the brain that controls our ability feel pleasure). It is unclear why the treatment works, but the stimulation of these brain regions seems to help with emotional regulation and decreasing depressive thoughts and feelings. Preliminary research results are promising; DBS patients experienced a remission in depression symptoms for 6 months. However, the procedure is still considered experimental; very few people have undergone this type of treatment for depression.
DBS is not without potential side effects, including: apathy, hallucinations, compulsive gambling, hypersexuality, cognitive dysfunction (problems with remembering words, paying attention, and learning new material), suicidal behavior, personality changes, and brain swelling or bleeding. However, the side effects may be temporary and related to the placement and calibration of the pacemaker.