Testing of an Interface for Synchronizing tACS-DBS With a Phase-locked-loop

NCT07139093 | Completed

• 2 other identifiers: PV7207_1SCHW 2023/2-1
• Study Type: interventional
• Target: 2
• Locations: 1 country
• Sites: 1

Brief Summary

The investigators aim to test an interface to phase-lock transcranial alternating current stimulation (tACS) and deep brain stimulation (DBS) for future studies investigating the effects of different time-lags between DBS and tACS on the behavioural and neural level. To test if the interface works in patients with DBS, the investigators record EEG during synchronized tACS-DBS in several patients. The investigators hypothesize that they can apply tACS at the desired phase-lags relative to DBS pulses and confirm this with EEG measurements of the DBS and tACS artifact.

Conditions

Deep Brain Stimulation; Parkinson's Disease (PD)

Keywords

deep brain stimulation; transcranial alternating current stimulation; EEG; synchronization; brain-computer interface

Outcome Measures

Primary Outcomes (1)

• Phase-locking success (delay to intended phase)

  The investigators will measure the temporal precision of the locking of the tACS to the DBS pulses should be seen. To this end, the tACS-DBS artifact and the triggers given from the interface device will be analysed offline in MATLAB.

  during stimulation procedure

Study Arms (1)

phase-lags

EXPERIMENTAL

Device: phase-lags * DBS will be applied at a fixed frequency between 15-30 Hz in one hemisphere only using the contact(s) of the clinical DBS settings. The amplitude of the electrode in the other hemisphere will be set to 0mA. * tACS will be applied closed-loop at the same frequency as DBS; with 4 phase lags relative to the DBS pulse (0°, 90°, 180°, 270°). tACS will be administered using the neuroConn DC-STIMULATOR PLUS. * EEG will be measured during this intervention with an analog (Digitimer) amplifier.

Device: DBS-coupled tACS

Interventions

DBS-coupled tACS DEVICE

tACS will be applied in a phase-coupled manner, so that tACS and DBS are synchronized

phase-lags

Eligibility Criteria

• Age: 35 Years - 85 Years
• Sex: all
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• Provision of written informed consent by the patient
• Age 35 - 85
• patient groups: Parkinson's disease, essential tremor, dystonia
• \>3 months after surgery for DBS

You may not qualify if:

• Epilepsy or history of seizures
• Existence of heart pacemaker or other metal implants in the body (except DBS)
• Pregnancy

Sponsors & Collaborators

• Universitätsklinikum Hamburg-Eppendorf: lead
• University of Twente: collaborator
• University of Oxford: collaborator

Study Sites (1)

University Medical Center Hamburg-Eppendorf

Hamburg, 20246, Germany

Location

Study Officials

• Bettina C. Schwab, PhD

  UKE Hamburg

  PRINCIPAL INVESTIGATOR

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: NA
• Masking: NONE
• Purpose: BASIC SCIENCE
• Intervention Model: SINGLE GROUP
• Sponsor Type: OTHER
• Responsible Party: SPONSOR

Model Details: Active DBS and active tACS with different phase-lags (at least 4: 0°, 90°, 180°, 270°)

Study Record Dates

• First Submitted: August 17, 2025
• First Posted: August 24, 2025
• Study Start: September 30, 2025
• Primary Completion: February 27, 2026
• Study Completion: February 27, 2026
• Last Updated: June 30, 2026

Record last verified: 2026-03

Data Sharing

• IPD Sharing: Will not share

Locations

DE (1)