"Smart" electrodes
Deep brain stimulation has been used to treat Parkinson's disease for more than 25 years, but the significant limitations of this method have pushed scientists to find ways to improve it. American researchers led by Professor Philip Starr from the University of California at San Francisco have developed the first fully implantable system for electrical stimulation, which uses feedback directly from the brain to fine-tune its work.
Traditionally, deep brain stimulation in Parkinson's disease involves the surgical implantation of a thin wire electrode into the brain, which provides constant stimulation of the region known as the basal ganglia. This approach is associated with undesirable side effects that require the intervention of a qualified specialist.
The method proposed by the authors, on the contrary, is adaptive, that is, it provides stimulation that is adjusted in real time in accordance with the signals coming from the patient's brain.
In a short-term study, two patients with Parkinson's disease were implanted with devices for adaptive deep brain stimulation. These devices differ from traditional ones in that they simultaneously monitor and modulate brain activity. Monitoring is provided by an electrode implanted on the surface of the primary motor cortex responsible for the normal movement of the body. The signals from this electrode are recorded by the program installed on the device, which determines the need for brain stimulation at the current time.
The program tested in the framework of the study perceived as a signal of the need to correct the stimulating effect of the profile of brain activity associated with dyskinesia or uncontrolled movements, which are a side effect of deep brain stimulation in Parkinson's disease. The level of stimulation decreased when brain activity associated with dyskinesia was detected and increased in its absence.
The results of the observations made by the authors demonstrated the effectiveness of adaptive deep brain stimulation in regulating motor activity disorders in Parkinson's disease. The improvements it provides are comparable to the results of continuous feedback-free stimulation, manually regulated by specialists.
In addition, adaptive stimulation provides savings of approximately 40% of the energy of the device's battery, compared with the energy costs of traditional devices. Due to the short duration of the observation periods, the researchers were unable to compare the number of periods of dyskinesia developing using different approaches. However, they suggest that variable brain stimulation will reduce the frequency of side effects and plan to find out this issue in longer clinical studies.
If the developers' hopes come true, adaptive deep brain stimulation will solve the problem of patients who are poorly amenable to treatment, in whom excessive brain stimulation is associated with severe dyskinesia.
Article by Nicole C Swann et al. Adaptive deep brain stimulation for Parkinson's disease using motor cortex sensing is published in the Journal of Neural Engineering.
Evgenia Ryabtseva, portal "Eternal Youth" http://vechnayamolodost.ru according to NIH/National Institute of Neurological Disorders and Stroke: Self-tuning brain implant could help treat patients with Parkinson's disease.