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Updated: Jul 24, 2026
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Intra-Operative Behavioral Tasks in Awake Humans Undergoing Deep Brain Stimulation Surgery
Published on: January 6, 2011
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Functional network differences between unilateral and bilateral deep brain stimulation of the subthalamic nucleus
Brendan Santyr1,2, Alexandre Boutet1,3, Mohamad Abbass2
1Division of Neurosurgery, Department of Surgery, University of Toronto, Toronto, ON, Canada.
NPJ Parkinson'S Disease
|July 17, 2025
Summary
Bilateral deep brain stimulation for Parkinson's disease enhances motor hub activity and improves outcomes compared to unilateral approaches. This surgical strategy may offer a mechanistic advantage for motor function recovery.
Area of Science:
- Neuroscience
- Neurosurgery
- Medical Imaging
Background:
- Deep brain stimulation (DBS) is a key treatment for Parkinson's disease (PD).
- The choice between unilateral and bilateral electrode implantation is a critical surgical decision.
- The precise therapeutic differences and underlying mechanisms between unilateral and bilateral DBS remain unclear.
Purpose of the Study:
- To investigate the neurophysiological effects of unilateral versus bilateral DBS in Parkinson's disease patients.
- To compare the recruitment of brain networks and associated clinical outcomes between the two surgical approaches.
- To elucidate potential mechanistic differences underlying motor improvements.
Main Methods:
- Functional magnetic resonance imaging (fMRI) was employed during active DBS.
- Brain activity in key motor and non-motor hubs was assessed during unilateral and bilateral stimulation.
- Clinical outcomes, particularly motor function, were correlated with imaging findings.
Main Results:
- Bilateral DBS significantly reinforced the activation of crucial motor network hubs.
- Unilateral DBS was associated with notable non-motor responses, which were reduced with bilateral stimulation.
- Enhanced recruitment of motor hubs during bilateral DBS correlated with improved motor outcomes.
Conclusions:
- Bilateral DBS in Parkinson's disease may offer superior motor control by optimizing the engagement of motor circuits.
- The reduction in non-motor responses suggests a more targeted therapeutic effect with bilateral implantation.
- These findings provide a potential mechanistic explanation for the observed clinical benefits of bilateral DBS.
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