A new study will test whether implanting an electrode to stimulate a brain circuit can safely treat depression caused by bipolar disorder. To monitor the effect of the stimulation on activity and mood, the study subjects will use smart watches and rings and smartphones that track their responses to the experimental treatment.

“We hope to use wearables and other sensor systems to map out how the stimulation is affecting patients’ mood and energy levels — to make it possible to monitor and tune deep brain stimulation therapy to treat this difficult-to-treat disorder,” said Jeffrey Herron. He is the project’s lead engineer and an assistant professor of neurological surgery at the University of Washington School of Medicine.

Bipolar disorder is a mental illness that causes extreme mood swings. Individuals with the condition can experience periods of profound depression as well as manic episodes marked by high energy, impulsiveness and reckless decision-making.

The lifelong disorder affects about 1 in 100 people worldwide. The bouts of mania can disrupt relationships and contribute to unemployment and financial ruin. In most cases, depression predominates, often with disastrous consequences: About one-third to one-half of bipolar patients will attempt suicide at least once. 

Current treatment focuses on psychotherapy and medication, including antidepressants for depression and antipsychotics for mania. But because these treatments often fail, researchers are exploring the use of deep brain stimulation, or DBS.

With this procedure, a thin electrode is placed in the brain through which a low-level electrical pulse is introduced to alter the function of neural networks. The electrode is powered and controlled by a generator implanted under the skin.

The pulses’ strength and frequency can be adjusted wirelessly from a tablet device, allowing the healthcare team to fine tune the treatment’s effect.

Ten patients will participate in the five-year study.

DBS is used with success to treat epilepsy, Parkinson’s disease, tremor and obsessive-compulsive disorder (OCD), and has been investigated for treatment-resistant depression.

In the new study, the researchers will evaluate whether placing electrodes in the same brain circuit implicated in OCD — a brain structure called the ventral capsule/ventral striatum (VC/VS) — can reduce or prevent depression without triggering mania.

This is of particular concern because bipolar patients can develop a mixed state of mania and depression that is linked to an increased risk for suicide.

The researchers think the VC/VS circuit may be involved bipolar depression because the circuit is linked to two OCD behaviors that resemble behaviors that also seen in individuals with a bipolar disorder: avoidant behavior, which resembles bipolar depression, and hyperactivity, which resembles bipolar mania.

To monitor the effect of the neuromodulation and alert patients’ healthcare providers of any trouble, the patients will be monitored with smart watches and rings that can record heart rate, body temperature, activity level, and sleep quality and duration. This data can be examined with data collected by the implanted electrode, which can monitor neuronal activity in the brain circuit.

Herron’s team will be charged with creating the software and system needed to capture, process and interpret the data collected by the devices. The challenge, he said, will be to collect and integrate all these data so they provide meaningful information for the patient and the healthcare team. These data will not only help tell how well the treatment is working, but also alert a care team when the patient is showing signs of depression or mania.

Source: https://newsroom.uw.edu/blog/study-to-test-deep-brain-stimulation-for-bipolar-depression