Distinct brain signal patterns across connected regions may help explain Parkinson’s symptoms and inform more targeted treatments, a study suggests.
Researchers identified two types of beta activity, low-beta and high-beta, with different spatial, temporal and potential functional roles across brain networks involved in Parkinson’s.
The findings suggest that the timing, coordination and direction of these electrical signals may be key to understanding the disease’s symptoms.
The study was carried out at UT Southwestern Medical Center and involved 23 people undergoing deep brain stimulation (DBS) implantation surgery for Parkinson’s disease.
DBS involves implanting electrodes that deliver controlled electrical impulses to the brain.
The procedure allowed researchers to record electrophysiological signals, or patterns of electrical brain activity, from multiple brain networks at the same time and examine how they were related.
“We’ve known for many years that abnormal electrophysiological activity in the brain is present in Parkinson’s disease, but it was believed to be isolated to a single region,” said senior author Nader Pouratian, chair and professor of neurological surgery at UT Southwestern and an investigator in the Peter O’Donnell Jr. Brain Institute.
“These findings suggest that Parkinson’s disease involves a sequence of precisely timed events across an individual’s brain networks that reflect a deficiency in dopamine, the chemical messenger that plays a key role in many physical and emotional body functions.”
Dopamine deficiency leads to common Parkinson’s symptoms including bradykinesia, or slowness of movement, rigidity and resting tremors.
The researchers tracked beta activity, a type of electrical brain oscillation, during DBS implantation.
They found that low-beta and high-beta signals had distinct spatial, temporal and potential functional roles across the Parkinson’s network.
The results suggest Parkinson’s is not explained simply by the presence or strength of beta activity, but also by the coordination, timing and direction of the two signals across interconnected brain regions.
“These novel findings shift the field for future therapeutic development, especially as it relates to deep brain stimulation, which involves implanting electrodes to deliver controlled electrical impulses,” said first author Jeong Woo Choi, assistant professor of neurological surgery at UTSW.
“Current DBS is relatively simple, using a system that is turned on with constant stimulation to reduce abnormal neural activity and improve movement symptoms.
“By developing a deeper understanding of the dynamic network processes involved in Parkinson’s, we may find that high-beta and low-beta oscillations need to be measured and targeted separately for more precise and responsive forms of DBS.”
The study builds on previous research at UT Southwestern into the causes and treatments of Parkinson’s disease, including detailed work on excessive beta oscillations.
“We are one of only a handful of centre in the country that have optimised the use of this opportunity to simultaneously measure brain signals during surgery from multiple brain regions,” Pouratian said.
“This enables us to link and understand how activity across brain regions interacts to produce symptoms of disease and to understand how treatments affect these brain networks.”
