Physiological Regulation of Chronic Tinnitus

The present project involves research on humans with the aim to characterize the reduction of chronic, continuous, non-pulsatile and debilitating tinnitus in humans by comparing neurofeedback (fMRI or EEG) to the current gold standard behavioral cognitive therapy.

Chronic tinnitus is affecting 10-15% of people typically for many decades, with increasing prevalence with aging. Multiple therapy forms for tinnitus exist (including cognitive behavioral therapy, external white noise stimulation, meditation, and various kinds of alternative approaches), but up to now, no generally accepted successful treatment exists. Previously, it was shown that voluntary control of the activation of the auditory cortex can be learned by means of real-time functional Magnetic Resonance Imaging (fMRI) neurofeedback, and that it may alleviate tinnitus symptoms. The same seems to hold for learned increase of alpha activity localized in the auditory cortex through electroencephalography (EEG) neurofeedback. Given the high prevalence of chronic tinnitus, its significant burden for affected individuals, and given the absence of generally effective therapy, neurofeedback training for tinnitus has the potential to become a clinical application.

The main goal of this project is to comparatively assess tinnitus reduction using neurofeedback (fMRI or EEG) compared to cognitive behavioral therapy in participants with chronic severe tinnitus.

* The participants are assigned to 3 different experimental groups (EEG neurofeedback, fMRI neurofeedback, or cognitive behavioral therapy). The participation per subject will last from 4 to 12 months.
* The participants undergo medical tests including audiological tests as well as questionnaires related to tinnitus and quality of life at different timepoints of the study (pre and post training visits).
* At the end of the experimental visits, each participant will have one early and one late post-assessment evaluation visits.
* In order to evaluate the longer-term evolution of tinnitus over time, long-term follow-ups will be scheduled starting at 9 months after the final experimental visit, and will occur every 4.5 months thereafter, until research ends (for a maximum of 5 years).

Eligibility Criteria:
Inclusion Criteria:

1. Age between 18 to 80 years
2. Tinnitus Handicap Inventory ≥ 48
3. Chronic, persistent, non-pulsatile tinnitus for minimum 6 months
4. Functional hearing
5. Normal inner ear structure assessment using an ear microscope, normal tympanic membrane mobility
6. Participant willing, able and available to participate in the entire research, including completion of questionnaires and traveling to research sites for the duration of the trial

Exclusion Criteria:

1. Contraindication to MRI (e.g. non compatible cochlear implant, pacemaker, deep brain stimulation)
2. Conductive hearing loss exceeding 20 dB at two or more frequencies
3. Known diagnoses causing tinnitus or hearing loss:

   * Known systemic disease (vestibular schwannoma, endolymphatic hydrops)
   * Lesion in central nervous system, including history of severe cranio-cerebral trauma
   * Acute ear canal or middle ear inflammation or effusion
4. Significant neurologic disease, psychiatric disease, substance abuse or acute allergic disease
5. Ongoing medication that is known to treat, influence, or cause tinnitus (e.g. high-dose aspirin, quinidine, aminoglycosides)
6. Ongoing or recent (completed since less than 4 weeks) tinnitus therapy (e.g. tinnitus maskers, acupuncture)
7. Participation in competitive or pharmacological study
8. Pregnant woman