RecruitingNot ApplicableNCT07393880

Bimodal Electrical-Sound Stimulation and Auditory Training for Chronic Tonal Tinnitus

Non-Invasively Re-Training the Tinnitus Brain Using Bimodal Electrical-Sound Stimulation (NITESGON-ADT): Protocol for a Prospective, Double-Blind, Randomised Controlled Trial

Sponsor

University of Dublin, Trinity College

Enrollment

100 participants

Start Date

Jan 30, 2026

Study Type

INTERVENTIONAL

Conditions

Chronic Tinnitus Tinnitus Tinnitus, Subjective

Summary

This study tests whether pairing non-invasive stimulation of the greater occipital nerve (NITESGON) with an attentionally demanding auditory frequency discrimination training task reduces tinnitus loudness and tinnitus-related distress. One hundred adults with chronic tonal tinnitus will be randomised to one of four groups in a 2×2 factorial design: real versus sham NITESGON and active versus passive listening during auditory stimulation. Participants complete eight sessions across four weeks, with outcomes assessed at baseline, end of treatment, 28 days post-treatment, and 6 months post-treatment.

Eligibility

Min Age: 18 YearsMax Age: 80 Years

Inclusion Criteria7

Adults aged 18-80 years
Continuous subjective tinnitus for \>3 months and ≤5 years
Predominantly tonal tinnitus (unilateral or bilateral)
Screening THI score 28-76
Minimum Masking Level (MML) 20-80 dB HL
No prior tinnitus neuromodulation treatment
Able to comply with eight sessions over four weeks and follow-up assessments

Exclusion Criteria17

Objective tinnitus or predominantly somatic tinnitus
Pulsatile tinnitus
Evidence of conductive hearing loss (abnormal otoscopy or tympanometry)
Pure-tone audiometry exclusions: \>40 dB HL at any frequency 250 Hz-1 kHz OR \>80 dB HL at any frequency 2-8 kHz in either ear
Hearing aid use initiated within the past 90 days
Active implantable medical device (e.g., pacemaker, DBS, cochlear implant)
LDL \<30 dB SL at 500 Hz in either ear
Diagnosis of temporomandibular joint disorder or occipital neuralgia
Severe anxiety (STAI \>120/160)
Cognitive impairment (MMSE \<25)
Severe depressive symptoms (BDI ≥30)
Diagnosis of Menière's disease
Current pregnancy
Involvement in medicolegal cases
History of auditory hallucinations
Current prescription of central nervous system drugs likely to alter neuromodulatory function (e.g., noradrenergic, dopaminergic, serotonergic, benzodiazepine, cholinergic, or other psychoactive medications)
Currently enrolled in another interventional study

Print for Your Doctor

Interested in this trial?

Get notified about updates and connect with the research team.

Interventions

DEVICEReal NITESGON

Real NITESGON is delivered transcutaneously via two saline-soaked sponge electrodes (35 cm² each) positioned bilaterally over the C2 dermatomes to target the greater occipital nerve. Stimulation consists of a 20 Hz sinusoidal current at 1.5 mA peak-to-peak, ramped up over 30 seconds and ramped down over 5 seconds. It is administered concurrently with the task for \~45 minutes per session, across eight sessions (2/week) over 4 weeks.

DEVICESham NITESGON

Sham NITESGON is delivered using two saline-soaked sponge electrodes (35 cm² each) positioned bilaterally over the C2 dermatomes. The sham condition mimics real stimulation sensations via a 30-second ramp-up followed by a brief ramp-down, with no sustained current thereafter. Sham is administered concurrently with the task for \~45 minutes per session, across eight sessions (2/week) over 4 weeks.

BEHAVIORALActive Listening

ADT is delivered using a three-interval, three-alternative forced-choice (3I-3AFC) frequency discrimination task. Standard tone frequencies are individually selected using ERB/critical-band spacing, centered one octave below each participant's dominant tinnitus pitch and extending to lower frequencies; the highest standard is kept below the tinnitus pitch region. Tones are presented binaurally via headphones, with presentation levels calibrated to individual audiometric thresholds and matched for equal SPL in both ears.

BEHAVIORALPassive Listening (Control)

VisDT uses a three-interval, three-alternative forced-choice (3I-3AFC) paradigm with Gabor patches (sinusoidal gratings windowed by a Gaussian envelope) of fixed spatial frequency (6 cycles/degree) and fixed spatial spread; on each trial, one interval contains an orientation deviant relative to the standard. During VisDT, participants attend to the visual task while concurrent binaural tones are presented passively using a predetermined, non-adaptive schedule. Auditory tones are individually calibrated to audiometric thresholds and drawn from ERB-spaced frequencies centered one octave below the dominant tinnitus pitch and extending to lower frequencies, with the highest frequency kept below the tinnitus pitch region.