Widespread Cortical Beta Oscillations Linked to Shared Brain Networks Modulated by Dopamine

Core Concepts

Cortical beta oscillations are the most widely distributed resting brain rhythm, connected to a shared cortico-subcortical network that is modulated by dopamine signaling.

Abstract

The study investigated the spatial distribution, connectivity, and neurochemical correlates of cortical beta oscillations in the human brain. Key findings: Beta activity was the most widely distributed dominant resting brain rhythm, observed across the entire cortex, including frontal, temporal, cingulate, insular, and parietal regions. Cortical areas exhibiting dominant beta oscillations shared a common functional and structural brain network, characterized by strong connectivity to prefrontal, cingulate, and parietal areas, as well as subcortical regions like the basal ganglia. This beta-associated brain network showed significant overlap with spatial patterns of dopamine uptake, as measured by PET imaging, suggesting that beta oscillations are modulated by dopaminergic signaling. The widespread distribution of beta activity and its relationship to dopamine-modulated brain networks provide a unifying circuit-based framework for understanding the diverse functional correlates of beta oscillations, including motor control, cognition, memory, and emotion. These findings have implications for the use of beta oscillations as a biomarker and control signal in closed-loop neurotechnology for the treatment of dopaminergic disorders.

Stats

Beta oscillations were the dominant rhythm in 56.6% of the recorded cortical channels. The beta-associated brain network showed significant positive correlations with dopamine uptake in the cortex (rho=0.22) and basal ganglia (rho=0.50).

Quotes

"Beta activity was the most frequent and most widely distributed resting rhythm across all lobes of the human brain including frontal, temporal, cingulate, insula and parietal lobes." "The beta network showed significantly higher connectivity to prefrontal, cingulate and other large-scale brain areas with the basal ganglia, including substantia nigra, striatum, pallidum and subthalamic nucleus." "We found significant and specific overlap of the functional and structural connectivity maps seeded from beta-dominant cortical brain areas with the spatial patterns of dopamine uptake in the human brain."

Key Insights Distilled From

Cortical beta oscillations map to shared brain networks modulated by dopamine

by Chik... at www.biorxiv.org 02-17-2024

https://www.biorxiv.org/content/10.1101/2024.02.16.580657v1

Deeper Inquiries

How do the dynamic fluctuations of beta oscillations relate to phasic dopamine release and neural reinforcement processes in the brain?

The dynamic fluctuations of beta oscillations in the brain are closely related to phasic dopamine release and neural reinforcement processes. Beta oscillations have been found to be modulated by dopamine, a neurotransmitter critically involved in synaptic plasticity and reinforcement learning. Studies have shown that changes in dopamine levels can lead to alterations in beta activity, especially in conditions like Parkinson's disease where there is a loss of dopaminergic innervation. Phasic dopamine release, which refers to the rapid and transient release of dopamine in response to specific stimuli or events, can influence the amplitude and frequency of beta oscillations. Neural reinforcement processes involve the orchestration of neural population dynamics for the production of neural trajectories. Beta oscillations may serve as a signal of the maintenance of the "status quo" on a neural level, indicating whether a motor or cognitive state should be changed or maintained. This concept can be linked to neural reinforcement, where beta activity reflects the stability of neural dynamics in frontostriatal circuits modulated by dopamine. Higher beta activity may indicate a stable neural state, while lower beta activity could lead to the emergence of new neural trajectories and potential behavioral changes.

What are the potential limitations of using beta oscillations as a biomarker for dopaminergic disorders, given its widespread distribution and involvement in diverse functional domains?

While beta oscillations show promise as a potential biomarker for dopaminergic disorders, there are several limitations to consider. One major limitation is the widespread distribution of beta activity across various functional domains in the brain. Beta oscillations have been associated with motor control, cognition, memory, and emotion, making it challenging to pinpoint specific changes in beta activity solely related to dopaminergic dysfunction. The overlap of beta activity in different brain regions involved in diverse functions complicates the interpretation of beta oscillations as a specific biomarker for dopaminergic disorders. Additionally, the dynamic nature of beta oscillations and their modulation by various neurotransmitters and neural processes can introduce variability in the biomarker signal. Factors such as individual differences in neural circuitry, task demands, and environmental influences can impact beta activity, making it less specific as a biomarker for dopaminergic disorders. Furthermore, the complex interplay between beta oscillations, dopamine release, and neural dynamics requires a comprehensive understanding of the underlying mechanisms to effectively use beta activity as a biomarker.

Could targeted interventions to modulate beta activity serve as a neuroprosthetic approach to restore optimal dopaminergic tone and neural dynamics in clinical conditions?

Targeted interventions to modulate beta activity hold potential as a neuroprosthetic approach to restore optimal dopaminergic tone and neural dynamics in clinical conditions, especially in dopaminergic disorders like Parkinson's disease. By leveraging the relationship between beta oscillations and dopamine modulation, interventions can be designed to influence beta activity and, in turn, regulate dopaminergic tone and neural dynamics. One approach could involve closed-loop neurostimulation techniques that use beta activity as a feedback signal to adjust therapeutic interventions in real-time. Adaptive deep brain stimulation, for example, has shown promise in Parkinson's disease by using beta oscillations to adapt stimulation parameters based on the individual's therapeutic demand. By modulating beta activity through targeted interventions, it may be possible to restore optimal dopaminergic tone and neural dynamics in patients with dopaminergic disorders. Furthermore, advancements in neurotechnology and neural engineering could enable precise and personalized interventions to modulate beta activity in specific brain regions associated with dopaminergic dysfunction. By developing neuroprosthetic devices that can monitor and regulate beta oscillations, clinicians may have a new tool to restore neural dynamics and improve symptoms in patients with dopaminergic disorders. Ongoing research in this area may lead to innovative therapeutic approaches that harness the potential of beta modulation for neuroprosthetic interventions.