Researchers were successful in wirelessly recording the direct brain activity of patients with Parkinson disease, while also showcasing the first demonstration of adaptive deep brain stimulation at home.
Long-term recording of brain activity in patients with Parkinson disease (PD) was found to be possible through a project funded by the National Institutes of Health (NIH) Brain Research Through Advancing Innovative Neurotechnologies (BRAIN) Initiative.
The project, whose findings were published this week in Nature Biotechnology, assessed neural recordings via invasive deep brain stimulation (DBS) devices. DBS, an effective therapy for PD associated with motor function improvement, was cited by researchers to be further improved by a better understanding of how its stimulation pulses influence signs and symptoms of PD.
“One approach to addressing this knowledge gap has been the analysis of invasive cortical or subcortical field potential recordings from externalized leads, either during lead implantation surgery or for a few days afterwards in the hospital setting,” said the study authors.
As brain activity patterns, or neural signatures, that identify PD symptoms are typically recorded in clinical settings over short periods of time, researchers sought to assess whether these recordings could instead be conducted over extended periods of time and in a home environment.
Using an adaptive version of DBS developed in the laboratory of Philip Starr, MD, PhD, at the University of California, San Francisco, they examined 5 patients with PD for up to 15 months after implantation.
“This device can transmit neural data at a sampling rate of up to 1000 Hz to an external Windows-based tablet up to 12 meters away, allowing freedom of movement,” explained the study authors. “The interface can be tailored for easy at-home use and for different disease indications by programming customized functions within its application programming interface.”
After streaming the bilateral 4-channel motor cortex and basal ganglia field potentials at home at levels over 2600 Hz, researchers then paired these findings with behavioral data from wearable monitors to identify the neural states of inadequate or excessive movement.
They were found to successfully validate patterns in individual-specific neurophysiological biomarkers during normal daily activities, which was then leveraged to adjust the levels of stimulation provided through the DBS device based on patients’ personalized needs.
"This is the first device that allows for continuous and direct wireless recording of the entire brain signal over many hours," said Starr in a statement. "That means we are able to perform whole brain recording over a long period of time while people are going about their daily lives."
Addressing ethical and privacy concerns on all-day brain recording, Starr said that he and fellow researchers have told patients to feel free to remove wearable devices and turn off their brain recordings when engaging in private activities.
Researchers concluded that similar approaches may be applicable to other neurologic and psychiatric disorders treatable by invasive neuromodulation.
Gilron R, Little S, Perrone R, et al. Long-term wireless streaming of neural recordings for circuit discovery and adaptive stimulation in individuals with Parkinson’s disease. Nat Biotechnol. Published online May 3, 2021. doi:10.1038/s41587-021-00897-5