Compensation by cerebral cortex in Parkinson’s

Editorial

November 1, 2023

Cortical compensation largely determines the severity of motor and cognitive symptoms in Parkinson’s disease, new research shows.1 “Future interventions should focus on strengthening cortical compensation, and not just on normalizing dopamine levels in the basal ganglia,” says co-researcher and neurologist Rick Helmich, from Radboud university medical center.

In Parkinson’s, a severe deficiency of dopamine occurs, causing the basal ganglia to function less well. Dopamine is produced in the substantia nigra and released in basal ganglia. “Dopaminergic medication helps to relieve symptoms, but an earlier study2 already showed that people with Parkinson’s also benefit from non-drug treatments such as regular exercise,” says Helmich. “In this new study, we tested the hypothesis that inter-individual differences in the severity of Parkinson’s symptoms are determined by compensatory cortical mechanisms.”

“Some patients drew a zebra crossing in their own home to walk better with those visual patterns”

Researcher and neurologist Rick Helmich

Research

Using functional MRI, brain activity was measured during a task in which people had to make movements that varied in difficulty. A total of 353 people with Parkinson’s disease (≤5 years of disease duration) and 60 healthy controls were measured. Consistent with the researchers’ hypothesis, increased brain activity was visible in the parie