Tinnitus Relief: 2021 Study on Sound Masking Efficacy

Sound Masking in Tinnitus: What a 2021 Clinical Trial Reveals About Partial vs. Total Relief

In a 2021 University of Iowa clinical trial, 44% of participants using total masking reported a significant reduction in tinnitus distress. The study, led by Dr. Richard Tyler, directly compared total masking, partial masking, and counseling alone. It provides some of the most recent and direct clinical evidence on how sound masking devices perform as part of a structured therapeutic program. The findings challenge straightforward assumptions about these devices and highlight the complex, individualized nature of tinnitus treatment.

What Are Total and Partial Sound Masking?

Sound masking is a therapeutic sound therapy strategy. It uses external noise to alter a patient’s perception of their internal tinnitus sound.

Total masking involves playing an external sound, such as white noise or nature sounds, at a volume loud enough to completely cover or “drown out” the tinnitus. The goal is to render the tinnitus inaudible, providing temporary relief and quiet. This approach is often what people first imagine when they think of using a sound machine for tinnitus relief.

Partial masking uses an external sound at a lower volume, one that blends with the tinnitus rather than covering it entirely. The tinnitus remains audible but becomes less prominent or distinct. The theory is that by reducing the contrast between tinnitus and silence, the brain’s auditory system can begin to habituate to the tinnitus signal, learning to classify it as unimportant background noise.

How a Sound Masking Clinical Trial Was Structured

The study, published in the Journal of the American Academy of Audiology, divided treatment into arms. Participants first chose whether to use hearing aids based on their own hearing needs and preference. They were then randomly assigned to one of three treatment groups: Tinnitus Activities Treatment (TAT) counseling alone, TAT counseling with partial masking, or TAT counseling with total masking. The Tinnitus Handicap Questionnaire (THQ) served as the primary outcome measure to track changes in distress and life impact.

This two-factor design—hearing aid use and masking type—allowed researchers to see how masking interacted with other common interventions. Importantly, all groups received the same foundational counseling, isolating the specific additive effect of the masking sound.

Key Outcomes: Average Scores Masked Individual Variation

The results revealed no statistically significant difference in average benefit between counseling, partial masking, and total masking groups. However, averages tell only part of the story.

For participants not using hearing aids, total masking produced the largest average decrease in THQ score (25%), followed by counseling alone (15%) and partial masking (14%). When looking at the proportion of individuals who achieved a “significant benefit,” total masking appeared more effective: 62% (8 of 13) in the total mask group reported significant improvement, compared to 36% (8 of 22) in counseling alone and 33% (8 of 24) in partial masking.

For hearing aid users, the pattern shifted. Partial masking yielded the highest average improvement (16%) and the highest proportion of individuals with significant benefit (46%, or 6 of 13).

The trial’s major conclusion, stated frankly by the authors, was that “Individual differences were large. Many benefited from their treatment, but some did not.” They suggested a patient’s expectations might be a key influence on outcomes.

The Neuroplasticity Rationale Behind Sound Therapy

Sound masking works on principles of neuroplasticity—the brain’s ability to reorganize its neural connections. Chronic tinnitus is believed to involve maladaptive neural networks that give the phantom sound excessive salience, tagging it as a threatening or important signal that demands attention.

By introducing consistent, neutral external sound, masking devices can help alter this neural activity. Total masking may provide immediate negative reinforcement (relief from an unpleasant sound), while partial masking aims for long-term habituation by reducing the neural contrast between tinnitus and the auditory environment. Both strategies are part of broader neuroplasticity-based approaches to tinnitus management that seek to retrain the brain’s response.

When Hearing Aids and Smartphone Apps Enter the Mix

The interaction between hearing aids and masking in the Tyler trial is noteworthy. For individuals with hearing loss, amplification of ambient environmental sounds through hearing aids can itself provide a form of partial masking, which may explain the altered effectiveness of separate masking devices in that group.

Further, the rise of smartphone apps has made sound therapy more accessible. A separate 2021 study by Perreau, Tyler, and colleagues in the American Journal of Audiology evaluated the ReSound Tinnitus Relief app in cochlear implant users with tinnitus. They found that patients could successfully use a phone app to select acceptable masking sounds, and word recognition scores were not negatively affected by the therapy. This supports the feasibility of app-based delivery, a convenient method for administering partial or total masking soundscapes.

Practical Applications: How to Use Sound Masking Effectively

Based on clinical evidence, sound masking is not a one-size-fits-all solution. Its effectiveness is part of a broader, personalized management plan.

Integration with Counseling is Non-Negotiable

The Tyler trial embedded masking within Tinnitus Activities Treatment, a comprehensive counseling protocol. Successful tinnitus management almost never involves a device alone. Effective counseling helps patients understand their condition, reduces fear and anxiety, and provides strategies for attention management and sleep improvement. This psychological component is critical for positive long-term outcomes.

Navigating the Choice Between Partial and Total Masking

Patients and clinicians must consider the goal. Is the primary need immediate relief during acute distress or difficulty sleeping? Total masking might be a suitable tool. Is the goal long-term habituation and reducing tinnitus awareness during daily activities? Partial masking, often recommended at a volume just below or mixed with the tinnitus sound, may be the preferred strategy. A clinical trial period for each method can help determine personal preference and effectiveness.

Acknowledgement of Limitations and Comorbidities

Sound masking is not appropriate for everyone. Patients with hyperacusis (heightened sensitivity to sound) or certain forms of misophonia (a strong negative emotional reaction to specific sounds) may find the additional sound irritating or exacerbating. Understanding a patient’s full profile of sound sensitivity is essential. For those with conditions like hyperacusis, strategies must be carefully calibrated, a topic explored in our review of sound sensitivity patterns. Furthermore, as the research shows, a significant minority of patients do not find meaningful relief from masking, underscoring the need for a diversified toolkit of management strategies.

Key Takeaways

• Total and partial masking are distinct strategies. Total masking aims to cover the tinnitus; partial masking blends with it to promote habituation.
• A 2021 clinical trial found large individual differences in effectiveness. While total masking showed a higher rate of significant benefit for non-hearing aid users (62%), there was no statistically significant winner overall, highlighting the need for personalized choice.
• Sound masking should be part of a comprehensive plan. It is most effective when combined with structured counseling, as the evidence for standalone device use is weak.
• Hearing aids can change the masking equation. For those with hearing loss, hearing aids provide ambient sound that may affect the utility of a separate masking device.
• Smartphone apps are a viable delivery method. Research supports the use of dedicated apps to deliver masking sounds, offering convenience and personalization.
• Masking is not for all sound sensitivities. It may be unsuitable or need careful adjustment for individuals with hyperacusis or certain types of misophonia.
• Patient expectations likely influence outcomes. A clear understanding of the goals and realistic expectations for sound therapy are important components of success.

This article is for informational purposes only. Consult a qualified professional for personalised advice.

Sources:
https://pubmed.ncbi.nlm.nih.gov/34965596/
https://pubmed.ncbi.nlm.nih.gov/34314254/
https://pubmed.ncbi.nlm.nih.gov/31210635/