Scientists have successfully remotely tracked the brain activity of people using a wireless device that transmits a continual stream of neural recordings. Describing their work in the journal Nature Biotechnology, the study authors explain how the implant allowed them to monitor five Parkinson’s disease patients' brain activity as they went about their daily lives for a period of up to 15 months.
Based on the information transmitted by the device, the researchers were able to remotely adjust the level of deep brain stimulation (DBS) delivered to each patient. Commonly used to treat Parkinson’s, seizure disorders, and even depression, DBS involves the use of electrodes to stimulate certain brain areas, thereby counteracting erratic activity and alleviating symptoms.
However, tracking the brain activity underlying these conditions has always been a challenge, primarily because such recordings could previously only be made while patients were physically present in a hospital or laboratory. Until now, it had never been possible to monitor individuals’ brain activity over long periods of time while they were at home.
Yet as study author Philip Starr explained in a statement, "if you ever hope to use in-hospital recordings to modify a disease state through adaptive stimulation, you must show that they are also valid in the real world."
In their write-up, the researchers reveal how they implanted electrodes into the motor cortex of each patient, allowing them to wirelessly stream participants’ neural activity as they went about their lives. This data was then cross-referenced with information about patients’ movement, collected using wearable sensors, in order to help the study authors identify the neural patterns associated with Parkinson’s related motor deficiencies.
As a result, the researchers were able to identify the unique neural signatures underlying each patient’s symptoms, and could therefore customize the level of DBS delivered to each individual.
"Because we are able to build a biomarker library for each patient, we can now program each DBS unit according to a patient's individual needs," said study co-author Ro’ee Gilron. "This includes personalized stimulation programs that adapt as the patient's needs change throughout the day."
While this new technology opens up new possibilities for the treatment of Parkinson’s disease and numerous other neurological disorders, the prospect of having one’s brain activity continuously observed also raises some important ethical concerns, primarily involving privacy.
"We have had patients approach us with concerns regarding privacy," said Dr Starr. "Although we are not at the point where we can distinguish specific normal behaviors from brain activity recording, it is an absolutely legitimate concern.”
Ultimately, Starr says that each patient must make the choice as to how deeply they wish to allow researchers to peer into their brains. “We have told patients to feel free to remove their wearable devices and to turn off their brain recordings whenever they engage in activities they would like to keep private," he said.