Modulation of limbic resting-state networks by subthalamic nucleus deep brain stimulation

Area of Science:

• Neuroscience
• Neurology
• Medical Imaging

Background:

• Subthalamic nucleus deep brain stimulation (STN-DBS) is established for Parkinson's disease motor symptoms.
• Its impact on non-motor symptoms and broader brain networks is less understood.
• Disseminated network modulation by STN-DBS requires quantitative evaluation.

Purpose of the Study:

• To quantitatively evaluate network-specific modulation induced by STN-DBS using Leading Eigenvector Dynamics Analysis (LEiDA).
• To assess the impact of STN-DBS on resting-state network (RSN) occupancy in Parkinson's disease patients.
• To compare RSN activity between STN-DBS ON and OFF conditions and with healthy controls.

Main Methods:

• Functional MRI data from 10 Parkinson's disease patients with STN-DBS were analyzed.
• Leading Eigenvector Dynamics Analysis (LEiDA) was employed to calculate RSN occupancy.
• Statistical comparisons were made between STN-DBS ON and OFF states, and against 49 age-matched healthy controls.

Main Results:

• STN-DBS significantly increased the occupancy of an orbitofrontal limbic subsystem compared to both DBS OFF and healthy controls (p < 0.006).
• A diffuse limbic RSN showed increased occupancy in patients OFF STN-DBS versus controls (p = 0.021), normalizing when STN-DBS was ON, indicating network rebalancing.
• These findings highlight STN-DBS's specific modulation of limbic system components, including the orbitofrontal cortex.

Conclusions:

• STN-DBS specifically modulates limbic RSNs, notably affecting the orbitofrontal cortex involved in reward processing.
• Quantitative LEiDA analysis provides valuable biomarkers for assessing the widespread effects of brain stimulation.
• These insights support personalized therapeutic strategies for Parkinson's disease by understanding network-level STN-DBS impacts.