Deeply stimulating: Prof. Hagai Bergman (right) and MD-PhD student Boris Rosin A new method for dynamic, electronic deep brain stimulation (DBS) developed at the Hebrew University of Jerusalem offers promise for better treatment of the symptoms of Parkinson’s disease.
The research was carried out by MD-PhD student Boris Rosin, Prof. Bergman and other members of the research team.
The suggested treatment involves an improvement of the existing deep brain stimulation (DBS) method. In DBS an electrode is implanted in a deep region of the brain, serving as a “brain pacemaker” delivering electrical stimuli at the implantation site. The result is that the patient receives a measure of immediate relief from these symptoms.
The new system uses real-time adaptive stimulation which disrupts the pathological neuronal activity associated with Parkinson’s disease instead of delivering constant stimulus. The research shows that this adaptive disruption, which the authors term closed-loop deep brain stimulation, is much more efficient than the constant electrical current stimulation being used in DBS today.
Although the underlying principles of its actions are not entirely clear, DBS has provided significant therapeutic benefits for movement disorders like Parkinson’s and for disorders like chronic pain and major depression. Under current practice, stimulation parameters, such as frequency and intensity of stimulation, must be programmed and adjusted over several months by a highly trained clinician following implantation of the DBS device, the goal being to maximize clinical improvement and minimize stimulation-induced side effects.
These adjustments typically occur every three to 12 months when the patient visits the clinic, with the parameters remaining the same between visits. Unfortunately, this results in stimulation that does not keep up with the dynamic nature of Parkinson’s.
“In recent years, the role of Parkinson’s-driven aberrant discharge patterns of neuronal activity have emerged as pivotal in the pathophysiology of the disease, and there is an urgent need for an automatic and dynamic system that can continually adjust the stimulus in response to ongoing pathological changes,” explain Rosin and Bergman.
To meet this challenge, the researchers tested several new paradigms for real-time adaptive DBS in a primate model of Parkinson’s disease, in which the delivered stimulus was triggered by the ongoing brain activity.
The researchers discovered that real-time adaptive DBS paradigms alleviated Parkinson’s motor symptoms and reduced abnormal neural activity more efficiently than standard, periodically adjusted DBS, while also providing new insight into brain activity underlying Parkinson’s pathology.
“It is our hope that in the near future we will see a new era of DBS strategies, based on real-time adaptive paradigms targeted at different pathological brain activity,” conclude Rosin and Bergman.
“This new stimulation strategy has the potential of being instrumental in the treatment of additional brain disorders in which a pathological brain activity pattern can be recognized and targeted by closed-loop stimulation”, the researchers say.
“These disorders also include prevalent psychiatric disorders such as obsessive-compulsive disorder, depression and even schizophrenia, which display pathological patterns of brain activity that bear certain similarities to those seen in Parkinson’s disease.”
The Hebrew University of Jerusalem