Abstract

Objective We describe a sensor and source space electroencephalography (EEG) analysis method for clinically established high frequency (140 Hz) deep brain stimulation (DBS) of the anterior nucleus of thalamus (ANT). We demonstrate this by evaluating the EEG effects time locked to DBS in a single participant.

Methods We used 1 s on and 5 s off stimulation on/off durations, providing a large number of trials. After artifact cleaning, the stimulation on-off EEG were averaged, and sensor and source space signals were determined and assessed.

Results We found an event-related potential (ERP) time locked to the DBS stimulation offset. Source localization analysis revealed that the main sources of this ERP were localized in the limbic system (Papez circuit). Further, the sources in the anterior cingulate cortex were found to oscillate in synchrony with the ERP.

Conclusions

This study shows that time-locked EEG analysis related to monopolar bilateral 140 Hz ANT DBS stimulation is feasible.

Significance The developed toolset reveals novel time-locked effects of high frequency ANT DBS on brain activity, which shows the future potential of sensor and source space analysis for DBS. The ERP findings might also prove useful in the optimization of epilepsy treatment with ANT DBS.

Highlights

We present a toolset for analyzing EEG effects during high frequency deep brain stimulation of the anterior nucleus of thalamus.

Time locked to DBS offset, an event-related potential (ERP) occurred in EEG.

Source analysis pointed to the limbic system and found synchronization of the anterior cingulate cortex with the ERP.

Competing Interest Statement

The authors have declared no competing interest.

Funding Statement

This work was supported by the Research Council of Finland (Flagship of Advanced Mathematics for Sensing Imaging and Modelling grant 359185).

Author Declarations

I confirm all relevant ethical guidelines have been followed, and any necessary IRB and/or ethics committee approvals have been obtained.

Yes

The details of the IRB/oversight body that provided approval or exemption for the research described are given below:

The study was conducted in accordance with the Code of Ethics of the World Medical Association (Declaration of Helsinki) and the Ethical Committee of Pirkanmaa Hospital District approved the study (R17132). Written informed consent was obtained from the participating patient.

I confirm that all necessary patient/participant consent has been obtained and the appropriate institutional forms have been archived, and that any patient/participant/sample identifiers included were not known to anyone (e.g., hospital staff, patients or participants themselves) outside the research group so cannot be used to identify individuals.

Yes

I understand that all clinical trials and any other prospective interventional studies must be registered with an ICMJE-approved registry, such as ClinicalTrials.gov. I confirm that any such study reported in the manuscript has been registered and the trial registration ID is provided (note: if posting a prospective study registered retrospectively, please provide a statement in the trial ID field explaining why the study was not registered in advance).

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Data Availability

Research data is conditionally available from the authors with a formal data sharing agreement.

AbbreviationsANTanterior nucleus of thalamusDBSdeep brain stimulationEEGelectroencephalographyDMNdefault mode networkGABAgamma-aminobutyric acidMRImagnetic resonance imagingfMRIfunctional magnetic resonance imagingSEEGstereo electroencephalogramLFPlocal field potentialERPevent related potentialFIASfocal impaired awareness seizuresASManti-seizure medicationCTcomputed tomographyEOGelectrooculogramECGelectrocardiogramDCdirect currentIPGimplantable pulse generatorEMGelectromyogramnTMSnavigated transcranial magnetic stimulationFIRfinite impulse responseICAindependent component analysisBEMboundary element methoddSPMdynamic statistical parametric mappingRTFrandom field theorySANTEstimulation of anterior nucleus of thalamus for epilepsyMRmagnetic resonance