Intelligent Brain Pacemaker to Help Reduce Parkinson’s Disease Symptoms

By HospiMedica International staff writers
Posted on 20 Aug 2024

Image: The implanted device responds to changes in brain signals, adjusting the amount of stimulation throughout the day (Photo courtesy of Phillp Starr Lab)

Parkinson’s disease (PD) which affects about 10 million people globally is due to the depletion of dopamine-producing neurons in deeper brain regions that regulate movement. This deficiency not only impairs motor skills but also impacts non-motor functions like mood, motivation, and sleep. Initially, treatment involves levodopa, which substitutes for dopamine. However, its side effects include dyskinesia, or uncontrolled movements, as it takes effect. When the drug's effect wears off, symptoms like tremors and stiffness return. Some patients resort to continuous deep brain stimulation (cDBS), which involves implanting electrodes that deliver steady electrical stimulation, reducing medication need and symptom fluctuation, though it may lead to imbalanced symptom control. Now, a new study has found that an implanted device regulated by the body’s brain activity can provide continuous and improved treatment for PD symptoms in some people with the disorder.

The feasibility study funded by the National Institutes of Health (NIH, Bethesda, MD, USA) and conducted by researchers at the University of California, San Francisco (San Francisco, CA, USA) found that adaptive deep brain stimulation (aDBS) showed greater efficacy in symptom control compared to traditional DBS, which provides uniform stimulation regardless of changing brain needs. In comparison, aDBS uses data taken directly from a person’s brain and utilizes machine learning to adjust the stimulation level in real-time as the person’s needs change over a period.

In the study, four participants already under conventional DBS identified their most persistent symptom despite ongoing treatment, often either involuntary movements or movement initiation difficulties. These participants then received aDBS in addition to their regular DBS. After months of refining the aDBS algorithm, they tested it at home, switching between standard DBS and aDBS. The study findings published in the journal Nature Medicine show that symptom management improved by about 50% with aDBS, with participants frequently recognizing when they were receiving aDBS due to noticeable improvements.

The fluctuating nature of brain drug levels post-medication could be more effectively managed with aDBS, which adapts to changing stimulation needs, thus enhancing its appeal for patients on high levodopa doses. Despite these promising results, broader application faces hurdles like the complex initial device setup, which demands significant expert intervention. Nevertheless, the researchers are optimistic about future automation that would minimize clinical visits for adjustments, facilitating wider clinical adoption and testing of aDBS therapy.

“This study marks a big step forward towards developing a DBS system that adapts to what the individual patient needs at a given time,” said Megan Frankowski, Ph.D., program director for NIH’s Brain Research Through Advancing Innovative Neurotechnologies® Initiative, or The BRAIN Initiative®, which helped fund this project. “By helping to control residual symptoms while not exacerbating others, adaptive DBS has the potential to improve the quality of life for some people living with Parkinson’s disease.”

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