Using altered auditory feedback to improve speech fluency in people who stutter

Effects of Altered Auditory Feedback on Speech Fluency

Not applicable Interventional Massachusetts Institute of Technology · NCT06011837

This study is testing whether using the Mumble Melody app, which changes how your voice sounds, can help people who stutter speak more fluently over a month of daily use.

Quick facts

PhaseNot applicable
Study typeInterventional
Enrollment100 (estimated)
Ages18 Years to 100 Years
SexAll
SponsorMassachusetts Institute of Technology Academic / other
Locations1 site (Cambridge, Massachusetts)
Trial IDNCT06011837 on ClinicalTrials.gov

What this trial studies

This study investigates the effects of the Mumble Melody app, which applies real-time voice transformations to enhance speech fluency in individuals who stutter. Participants will use the app daily for a month, selecting from various voice modes such as Unaltered, Whisper, Reverberated, and Harmonious. They will also engage in weekly at-home testing sessions to record their speech with and without the app, allowing researchers to assess the long-term impact of altered auditory feedback on fluency. The study aims to gather data on how these interventions affect speech over time in a naturalistic setting.

Who should consider this trial

Good fit: Ideal candidates are adults who identify as people who stutter and have access to compatible Apple devices.

Not a fit: Patients who do not stutter or those without access to the required Apple devices may not benefit from this study.

Why it matters

Potential benefit: If successful, this approach could significantly improve speech fluency and communication confidence for individuals who stutter.

How similar studies have performed: While the use of altered auditory feedback has been explored in other studies, this specific approach using a mobile app is relatively novel.

Eligibility criteria

Show full inclusion / exclusion criteria
Inclusion Criteria:

* Identifies as a person who stutters
* Is US citizen or green card holder currently residing in the US
* Has one of the following Apple devices:
* iPhone with iOS 12.0 or later
* iPad with iPadOS 12.0 or later
* iPod touch with iOS 12.0 or later
* Mac with macOS 11.0 or later and an Apple M1 chip or later
* Has a SEPARATE browser-supporting device with a microphone
* Is able to conduct the study in English
* Qualifies based on an initial screening evaluation (Greater than 2.5% Stuttering-Like Dysfluencies per syllable)

Exclusion Criteria:

-

Where this trial is running

Cambridge, Massachusetts

Study contacts

How to participate

  1. Review the eligibility criteria above with your treating physician.
  2. Visit the official trial page on ClinicalTrials.gov for the most current contact information and recruitment status.
  3. Contact the listed study coordinator or principal investigator to request pre-screening. Pre-screening is free and never obligates you to enroll.
Conditions Stuttering, Adult
Last reviewed 2026-06-15 by the Find a Trial editorial team. Information on this page is for educational purposes and is not medical advice. Always consult qualified healthcare professionals about clinical trial participation.