Five Tinnitus Phenotypes, One Sound Therapy: What a Study of 564 Patients Found

Researchers identified five distinct tinnitus phenotypes and found that a customized enriched acoustic environment reduced tinnitus severity by a clinically relevant margin in 78 percent of patients who completed four months of daily listening.

Tinnitus, the perception of ringing, hissing, or buzzing without an external sound source, is one of the most common hearing-related complaints in adults. For some people it is a passing nuisance; for others it disrupts sleep, concentration, and emotional wellbeing. One reason it has proven so difficult to treat is that tinnitus is not a single uniform condition: it varies in cause, sound quality, severity, and in how much distress it brings.

A research team in Spain and France asked whether tinnitus patients could be sorted into meaningful subtypes, or phenotypes, using data-driven clustering, and whether those subtypes respond differently to a sound-based therapy called an enriched acoustic environment. Their findings, published in Brain Sciences, suggest the answer to both questions is yes.

Background: Why the Researchers Looked at This

Clinicians have long observed that two people with tinnitus can have almost nothing in common. One may have substantial hearing loss and only mild annoyance, while another has a nearly normal audiogram and severe distress. Lumping such different patients together may be one reason clinical trials of tinnitus treatments so often produce mixed results. Subtyping, or phenotyping, aims to fix that by grouping patients according to shared, measurable characteristics.

The therapy studied here, an enriched acoustic environment, delivers a customized sound stimulus built around each person's hearing profile. The approach rests on evidence that enriching the auditory input reaching the brain can, over time, reduce how prominent tinnitus feels. What was missing was a clear picture of which kinds of patients respond best.

How the Study Was Done

The researchers analyzed a retrospective cohort of 564 people with tinnitus. First, a hierarchical decision cascade sorted each participant's audiogram into one of six hearing loss patterns. Then K-clustering, a statistical technique that groups similar cases without predefined labels, was applied to demographic, hearing, tinnitus, and emotional variables, including gender, average hearing threshold, hearing loss pattern, tinnitus onset age, duration, severity, lateralization, type of sound, aetiology, and emotional scores.

Participants received a customized enriched acoustic environment stimulus and were asked to listen to it for one hour every day over four months. Tinnitus severity and emotional scores were measured before and after the treatment period, allowing the team to compare outcomes across the phenotypes the clustering had identified.

What the Researchers Found

The clustering produced five distinct phenotypes, each with its own mix of hearing loss pattern, tinnitus characteristics, and emotional burden.

Among patients who completed the four-month program, the therapy delivered an average tinnitus severity reduction of 24.3 points, an improvement the authors describe as both clinically relevant and statistically significant, and 78 percent of completers improved.

Response was not uniform across the groups. The largest absolute improvements in both severity and emotional scores appeared in the two phenotypes, labeled PH3 and PH4, that started out with the highest tinnitus distress and emotional symptoms. At the same time, the relative change in severity was notably smaller in PH4, and the phenotypes differed clearly in who was excluded from treatment, who dropped out, and who failed to improve.

What It Means for People with Hearing Loss

The study strengthens two practical messages. First, tinnitus care may work better when it is matched to the patient: knowing someone's phenotype could eventually help clinicians predict who is most likely to benefit from a sound-based therapy and who may need a different approach. Second, sound enrichment itself continues to look promising, with a large share of patients improving on a treatment that is non-invasive and self-administered at home.

The finding that the most distressed patients gained the most absolute relief is especially notable, since those are the patients for whom effective options are needed most urgently.

Everyday Sound Enrichment Outside a Research Protocol

The treatment in this study worked by deliberately adding personalized sound to each patient's day. Outside the laboratory, the most common everyday source of enriched sound for people with hearing loss is amplification. Hearing aids do not treat or cure tinnitus; what clearer everyday sound can do, for some people whose tinnitus accompanies hearing loss, is make the tinnitus feel less noticeable against a fuller soundscape.

FDA-OTC hearing aids have made that kind of everyday sound access easier for adults with mild to moderate hearing loss. Panda Air is one example, a modern earbud-style hearing aid with 16-channel WDRC processing, multi-band adaptive noise reduction, Bluetooth for calls, TV, and music, and a fast-charge case providing 60 hours of total use, backed by a 5-year warranty and a 45-day trial that starts when the device is received.

In the same spirit as this study's customized stimulus, Air offers a self-fitting option: an optional app-based in-ear hearing test can measure hearing frequency by frequency and personalize gain and frequency response to the wearer's profile. The app and the test are optional, and Air works out of the box without either.

Limitations of This Research

This was a retrospective, cross-sectional analysis rather than a randomized controlled trial, so there was no untreated comparison group, and the observed improvement cannot be cleanly separated from placebo effects or the natural fluctuation of tinnitus over time. The headline 78 percent figure applies to patients who completed the four months of daily listening, and completion itself varied across phenotypes.

Cluster solutions also depend on the variables and methods chosen, so the five phenotypes will need confirmation in independent cohorts before they can guide routine care. Funding sources and conflicts of interest were not detailed in the abstract available through PubMed.

What to Do With This

For researchers, the study adds weight to the idea that tinnitus trials should stratify patients rather than treat them as one group. For people living with tinnitus, it offers grounded encouragement: a simple, structured daily listening therapy helped a large majority of those who stayed with it, and understanding your own tinnitus profile, ideally with a hearing professional, may be the first step toward the approach most likely to help.

Bouzou C, Fernández-Ledesma M, Cuesta M, Cobo P. Tinnitus Phenotypes and Their Response to the Enriched Acoustic Environment (EAE) Treatment. Brain Sciences. 2026. Retrieved from PubMed. https://doi.org/10.3390/brainsci16080894