Residual Inhibition of 40 Hz Burst Sound in Tinnitus Patients

Not Applicable

Completed

• Conditions: Tinnitus

• Registration Number: NCT06646302
• Lead Sponsor: Eye & ENT Hospital of Fudan University

Brief Summary

Tinnitus affects 10-15% of adults and is frequently associated with impaired quality of life, anxiety, and sleep disturbance. Conventional sound therapies based on continuous masking provide inconsistent and short-lived relief, and the neural mechanisms underlying residual inhibition (RI) remain unclear.

This study aims to determine whether 40 Hz burst stimulation with high-frequency carriers can achieve longer-lasting RI than continuous sound, and to explore its underlying neural mechanisms using EEG.

Detailed Description

Residual inhibition (RI) refers to the temporary reduction or disappearance of tinnitus following sound stimulation and provides an important clue for identifying patients who may benefit from acoustic therapy. However, the effects of different sound stimulation strategies on RI remain poorly understood.

This study evaluates whether 40 Hz burst-modulated sound achieves stronger and longer RI compared with conventional continuous stimulation. The trial follows a four-phase design:

Phase 1: Exploratory testing of burst versus continuous tones at different frequencies.

Phase 2: Large-scale validation in 265 patients. Phase 3: Development of a personalized stimulation protocol using adaptive spectral optimization.

Phase 4: EEG investigation of neural mechanisms, focusing on gamma oscillations and functional connectivity changes.

The primary outcomes are the strength and duration of tinnitus suppression. Secondary outcomes include EEG markers such as γ-band power spectral density and phase-locking value.

By combining behavioral and neurophysiological measures, this study aims to establish 40 Hz burst stimulation as a novel rhythm-based sound therapy and to provide mechanistic insights that may enable more effective, personalized tinnitus management.

Study Timeline

• Study First Submitted: 2024-10-09
• Study First Submitted QC: 2024-10-15
• Study First Posted: 2024-10-17
• Study Start: 2024-10-28
• Primary Completion: 2025-07-18
• Study Completion: 2025-07-18
• Status Verified: 2025-09
• Last Update Submitted: 2025-09-05
• Last Update Posted: 2025-09-11

Recruitment & Eligibility

• Status: COMPLETED
• Sex: All
• Target Recruitment: 265

Inclusion Criteria

1. Diagnosed with subjective tinnitus;
2. Chronic tinnitus: tinnitus course ≥ 1 month;
3. Normal middle ear function;
4. The average hearing threshold (defined as mean of 0.5, 1, 2, and 4 kHz) of the unaffected ear < 60 dB;
5. Tinnitus can be heard under normal circumstances.
6. Subjects are able to understand the purpose of the study, volunteer to participate and cooperate with the instructors to complete the experiment, and be willing to sign the informed consent.

Exclusion Criteria

1. Acute phase tinnitus;
2. Fluctuating tinnitus loudness;
3. Severe psychiatric disorders;
4. Inability to complete tinnitus testing;
5. Fluctuating or retrocochlear hearing loss;
6. Conductive hearing loss;
7. Currently participating in other research projects that may affect tinnitus;
8. Subjects who are not considered suitable for this clinical trial by the researchers.

Study & Design

• Study Type: INTERVENTIONAL
• Study Design: CROSSOVER

Primary Outcome Measures

Name	Time	Method
Tinnitus suppression strength	Immediately after the sound stimulation session.	Residual inhibition depth, 0-100% reduction
Residual inhibition duration	Immediately after the sound stimulation session.	Time in seconds until tinnitus returns to baseline after stimulation

Secondary Outcome Measures

Name	Time	Method
EEG spectral power changes	measured across the entire 10-minute EEG recording session (baseline, during stimulation, and post-stimulation)
EEG functional connectivity changes	measured across the entire 10-minute EEG recording session (baseline, during stimulation, and post-stimulation)

Trial Locations

Locations (1)

Eye & ENT Hospital of Fudan University; 🇨🇳 Shanghai, Shanghai Municipality, China