Combined Regulatory Effects of 40 Hz eTNS and Multisensory Stimulation on Brain Networks

NCT07668167 | Recruiting

• 1 other identifier: 20260612
• Study Type: interventional
• Target: 30
• Locations: 1 country
• Sites: 1

Brief Summary

The purpose of this study is to investigate the independent and interactive effects of 40Hz auditory, visual, and external trigeminal nerve stimulation (eTNS) on brain state dynamics and functional connectivity. While 40Hz visual and auditory sensory stimulation have been explored for potential cognitive and therapeutic benefits, the underlying mechanisms on large-scale brain networks and the potential effects of combining multiple modalities remain unclear. This study aims to determine whether multimodal co-stimulation genuinely compounds network-level effects or if targeted dual-pairings are more efficient for brain network reorganization. In this within-subject study, 23 participants will receive all eight possible combinations of 40Hz auditory, visual, and eTNS (targeting the maxillary branch) in a randomized order. Each stimulation condition will last for 5 minutes, separated by 1-minute inter-stimulus intervals. Continuous electroencephalography (EEG) will be recorded throughout the procedures to evaluate brain responses. The collected EEG data will be analyzed using microstate analysis, functional connectivity analysis, and graph-theoretic network analysis. Ultimately, the study seeks to understand how these non-invasive stimulation techniques, independently and together, drive large-scale network reorganization and optimize the balance between local specialization and global integration in the brain.

Conditions

Healthy Participants

Keywords

External trigeminal nerve stimulation (eTNS); 40Hz stimulation; Multimodal neuromodulation; Brain network reorganization; Network topology; Functional connectivity; EEG microstates

Outcome Measures

Primary Outcomes (1)

• Whole-Brain Functional Connectivity (Phase-Locking Value)

  Day1 (during the single experimental session)

Secondary Outcomes (3)

• EEG Microstate Dynamics (Mean Duration and Segment Density)

  Up to 1 hour (during the single experimental session)

• EEG Phase-Locking Value (PLV)-Derived Global Efficiency

  Day1 (during the single experimental session)

• EEG Phase-Locking Value (PLV)-Derived Small-World Propensity

  Day 1 (during the single experimental session)

Study Arms (1)

Experimental Crossover Group

EXPERIMENTAL

All participants are enrolled in this single crossover arm. Each participant will receive all eight combinations of 40Hz stimulation (auditory, visual, and external trigeminal nerve stimulation \[eTNS\] targeting the maxillary branch) in a randomized order, including a sham condition. Each stimulation condition lasts for 5 minutes, separated by 1-minute inter-stimulus intervals.

Device: 40 Hz External Trigeminal Nerve Stimulation; Device: 40 Hz Auditory Stimulation; Device: 40 Hz Visual Stimulation; Other: Sham Stimulation

Interventions

40 Hz Auditory Stimulation DEVICE

Auditory sensory stimulation delivered at 40 Hz for 5-minute durations

Experimental Crossover Group

40 Hz Visual Stimulation DEVICE

Visual sensory stimulation delivered at a frequency of 40 Hz for 5-minute durations

Experimental Crossover Group

40 Hz External Trigeminal Nerve Stimulation DEVICE

Electrical stimulation targeting the maxillary branch of the trigeminal nerve at a frequency of 40 Hz

Experimental Crossover Group

Sham Stimulation OTHER

Inactive control stimulation designed to mimic the sensory experience of the active modalities without delivering actual 40 Hz therapeutic stimulation

Experimental Crossover Group

Eligibility Criteria

• Age: 18 Years+
• Healthy Volunteers: Yes
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• Healthy adults aged ≥18 years old.
• Normal or corrected-to-normal vision and hearing (essential for 40Hz visual and auditory stimulation).
• Right-handedness.
• Willing to participate in the study and capable of providing written informed consent.

You may not qualify if:

• Personal or family history of epilepsy or seizures (crucial safety criteria for 40Hz flicker and electrical stimulation).
• History of any neurological or psychiatric disorders.
• Presence of metallic implants in the head, cardiac pacemakers, or other implanted electronic medical devices.
• Skin lesions, infections, or hypersensitivity at the eTNS stimulation site (maxillary branch of the trigeminal nerve).
• Current use of psychoactive medications or substances that may significantly alter EEG signals or brain state dynamics.
• Pregnant or lactating individuals.
• Poor sleep quality or irregular sleep-wake cycles prior to the experiment.

Sponsors & Collaborators

• Xidian University: lead
• Xi'an Central Hospital: collaborator

Study Sites (1)

Xidian University

Xi'an, Shaanxi, 71000, China

RECRUITING

Study Officials

• Xue-Juan Yang

  Xidian University

  PRINCIPAL INVESTIGATOR

Central Study Contacts

Xue-Juan Yang, Phd

CONTACT

86-029-81891070; xjyang@xidian.edu.cn

Xue-Juan Yang

CONTACT

15691826100; xjyang@xidian.edu.cn

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

Study Record Dates

• First Submitted: June 12, 2026
• First Posted: June 25, 2026
• Study Start: June 16, 2026
• Primary Completion: June 22, 2026
• Study Completion: June 23, 2026
• Last Updated: July 1, 2026

Record last verified: 2026-06

Data Sharing

• IPD Sharing: Will not share

Locations

CN (1)