Thalamic deep brain stimulation for tourette syndrome increases cortical beta activity

Area of Science:

• Neuroscience
• Clinical Neurology
• Biomedical Engineering

Background:

• Tourette syndrome (TS) is a neurological disorder characterized by involuntary tics.
• Deep brain stimulation (DBS) of the thalamus is an effective treatment for severe TS.
• The impact of thalamic DBS on cortical oscillatory activity in TS remains unclear.

Purpose of the Study:

• To investigate whether thalamic DBS influences beta activity in fronto-central electrodes in TS patients.
• To explore the relationship between concurrent electroencephalography (EEG) sources and probabilistic stimulation maps during DBS.

Main Methods:

• Resting-state EEG data were collected from TS patients during both DBS-on and DBS-off conditions.
• Statistical analysis utilized a mixed-effects linear model, with EEG source localization performed using eLORETA.
• Probabilistic stimulation maps were generated by correlating beta power changes with thalamic stimulation sites.

Main Results:

• A significant increase in beta power was observed during DBS-on compared to DBS-off states.
• Cortical beta activity modulation was localized to the midcingulate cortex.
• Posterior thalamic stimulation, particularly in the ventral posterior nucleus, showed more pronounced beta modulation.

Conclusions:

• Thalamic DBS in TS patients modulates beta frequency oscillations.
• These oscillations are presumed to be crucial for sensorimotor functions.
• The findings suggest a potential mechanism for DBS efficacy in TS pathophysiology.