Main image courtesy of Britannica.

Every year, approximately 16 million adults in the United States are affected by clinical depression. Common symptoms include persistent feelings of sadness or hopelessness, loss of interest in daily activities, and changes in sleep and appetite. 

The most common treatments for depression are drugs such as antidepressants and psychotherapies such as cognitive behavioral therapy, or CBT. However, these treatments don’t work for everybody, and often other options must be considered. That’s where neuromodulation comes in. 

Neuromodulation is technology that acts directly on the nerves and alters their activity in order to relieve symptoms of conditions such as depression. The first modern application of neuromodulation dates back to the 1960s in the form of deep brain stimulation (DBS). Today, there are many forms of neuromodulation that patients can be treated with. 

Electroconvulsive therapy

What this alternative treatment, which was first developed in 1938, entails

Electroconvulsive therapy (ECT) electrically induces a generalized seizure in order to manage mood disorders like depression. The patient is placed under anesthesia while their brain is briefly stimulated by an electric current. 

ECT is highly effective at treating severe major depression, with a success rate of approximately 80 percent. ECT treatment has been associated with short-term memory loss and learning difficulties which usually resolve with time. Psychiatrists have been working, and continue to work, on improving the safety of ECT for patients with severe mental illnesses. 

Other forms of ECT include:

Focal electrically administered seizure therapy

Focal electrically administered seizure therapy (FEAST) delivers focused electrical stimulation to the patient’s right prefrontal cortex. This minimizes the cognitive side effects of traditional ECT while maintaining its efficacy. 

Magnetic seizure therapy

Magnetic seizure therapy (MST) utilizes targeted magnetic pulses to induce a seizure. By being able to target specific parts of the brain, which is more difficult when electrically stimulating the brain, side effects are reduced while the treatment itself remains effective in patients.

Invasive brain stimulation

While these treatments are more invasive, they are highly effective in many cases

Early forms of brain surgery such as the prefrontal leucotomy and and prefrontal lobotomy were explored by scientists, but dwindled in use as their risks and complications came to light. Antipsychotic and antidepressant medications became available around the same time, making these surgeries unfavorable. 

However, with decades of research, scientists have discovered more precise, safe forms of brain surgery such as image-guided cingulotomy and capsulotomy. There are also other types of neuromodulation that have become possible due to developments in brain-imaging techniques. 

Deep brain stimulation

Deep brain stimulation (DBS) involves the implantation of electrodes in certain areas of the brain. These electrodes produce electrical impulses that are controlled by a device that is implanted under the skin of the upper chest. 

This procedure is generally well-tolerated and successful at treating conditions ranging from Parkinson’s to epilepsy, but is not currently FDA-approved for depression. The only psychiatric condition it can be used to treat as of now is severe obsessive-compulsive disorder (OCD).

Vagus nerve stimulation 

Vagus nerve stimulation (VNS) is similar to DBS and involves implanting an electrical pulse generator under the skin of the chest, connecting to and stimulating the vagus nerve. It may take several months to feel the effects. 

A less invasive form is transcutaneous VNS, which stimulates the vagus nerve through the skin instead. 

Noninvasive techniques 

These methods can help relieve depression without directly invading the body

​​

Repetitive transcranial magnetic stimulation (rTMS) is a noninvasive procedure that uses magnetic pulses to stimulate the brain and relieve symptoms of depression. It involves multiple sessions, but can relieve symptoms within a few weeks. 

Clinical trials typically focus on the area of the brain that has been found to play a crucial role in mental health and wellbeing —  the left dorsolateral prefrontal cortex. Accelerated rTMS involves multiple sessions in a day, which are about 40 minutes each. 

This treatment does not require anesthesia, has no cognitive side effects, and does not impose on daily routines. Patients can work, drive, and continue their lives as normal while being treated with rTMS, which makes it a promising neuromodulation method for depression. 

Alternatives to mainstream treatments for depression such as antidepressants and talk therapies can be necessary for people who have treatment-resistant depression. Although some forms of neuromodulation may have a bad reputation because of their historical misuse, scientific research in the field continues to grow. 

There are a variety of options available for patients nowadays, ranging from invasive procedures such as brain surgeries to other noninvasive procedures which may be safer and more well-tolerated. 

Regardless of your situation, know that you have options, and there is always hope. More advancements and improvements in neuromodulation are on the horizon!