Investigation of Anatomical Correlates of Speech Discrimination

March 10, 2026 updated by: Steward St. Elizabeth's Medical Center of Boston, Inc.
Understanding speech is essential for good communication. Individuals with hearing loss and poor speech discrimination often have little success with hearing aids because amplifying sound improves audibility, but not clarity of the speech signal. The purpose of this study is to determine the relative importance of the sensory cells of the inner ear and auditory neurons on speech discrimination performance in quiet and in noise. This information may be used as a predictor of hearing aid benefit. The investigators expect to find decreased speech understanding ability resulting from both loss of sensory cells and the loss of auditory neurons.

Study Overview

Status

Completed

Conditions

Intervention / Treatment

Detailed Description

Patients receiving routine audiologic evaluations who meet study criteria will be asked to participate in the study. Study participants will receive an ABR and DPOAE evaluation and speech-in-noise testing. Participants who are hearing aid candidates will be fit with loaner hearing aids with noise reduction technology for 2 weeks. Wave 1 amplitudes from the ABR, DPOAE levels, speech discrimination scores, unaided and aided speech0in-noise performance age, and pure tone thresholds will be recorded, as well as any audiologic diagnosis that may confound the results.

Study Type

Observational

Enrollment (Actual)

186

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Locations

  • United States
    • Massachusetts
      • Brighton, Massachusetts, United States, 02135
        • Steward St. Elizabeth's Medical Center

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Ages Eligible for Study

18 years to 100 years (Adult, Older Adult)

Accepts Healthy Volunteers

Yes

Sampling Method

Non-Probability Sample

Study Population

Adult patients referred from the St. Elizabeth's Department of Otolaryngology and self-referred patients to the Audiology Clinic.

Description

Inclusion Criteria:

  • Normal hearing to moderate sensorineural hearing loss
  • Sufficient English proficiency to complete speech discrimination testing in English

Exclusion Criteria:

  • Hearing loss less than a 45 dB HL pure tone average (average hearing thresholds at 500, 1000 and 2000 Hz)
  • Conductive hearing loss
  • Neurodegenerative disease

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

  • Observational Models: Cohort
  • Time Perspectives: Cross-Sectional

Cohorts and Interventions

Group / Cohort
Intervention / Treatment
low HIN difficulty- anesthetized
Subjects with normal OHC function and who will be undergoing an previously scheduled anesthetized procedure will be assigned into 2 groups based on their self-perceived HIN difficulty (high and low difficulty), and then undergo a test battery consisting of auditory threshold tests, objective HIN assays, OHC measurements, cognitive processing, and central auditory processing evaluations. Immediately after anesthetization, electrocochleography (ECochG) will be used to measure CAP amplitudes, which will be correlated with measurements obtained from unanesthetized subjects as described below. This aim will determine the optimal CAP recording method with the strongest correlation with HIN performance in humans
high HIN difficulty- anesthetized
Subjects with normal OHC function and who will be undergoing an previously scheduled anesthetized procedure will be assigned into 2 groups based on their self-perceived HIN difficulty (high and low difficulty), and then undergo a test battery consisting of auditory threshold tests, objective HIN assays, OHC measurements, cognitive processing, and central auditory processing evaluations. Immediately after anesthetization, electrocochleography (ECochG) will be used to measure CAP amplitudes, which will be correlated with measurements obtained from unanesthetized subjects as described below. This aim will determine the optimal CAP recording method with the strongest correlation with HIN performance in humans
Hearing Aid fitting: MAD
Microphone adaptive directionality (MAD) feature will be activated, the WDC set to linear, and the DNR minimized
Device: Hearing Aid fitting
Subjects with hfPTAs ranging from 0-55 dB HL will be recruitedwith 100 persons self-reporting difficulty HIN (> 50% of the time), and 100 persons reporting little difficulty HIN (< 50% of the time) will be randomly assigned to one of five groups (n = 200) based on enabled HA features using an online random assignment tool. Unaided HIQ and HIN assessments will be conducted in the sound field, and baseline DPOAE and CAP assessments will be measured. Subjects will be fit with binaural premium level receiver-in-the canal HAs (Phonak B90 or equivalent model at the start of the study) with 56 dB SPL gain receivers, using closed domes, and programmed to NAL-NL2 target gain, and randomly assigned to the groups.
Hearing Aid fitting: WDC
Wide dynamic compression (WDC) feature will be set to target levels, the MAD feature set to omnidirectional, and the DNR minimized.
Device: Hearing Aid fitting
Subjects with hfPTAs ranging from 0-55 dB HL will be recruitedwith 100 persons self-reporting difficulty HIN (> 50% of the time), and 100 persons reporting little difficulty HIN (< 50% of the time) will be randomly assigned to one of five groups (n = 200) based on enabled HA features using an online random assignment tool. Unaided HIQ and HIN assessments will be conducted in the sound field, and baseline DPOAE and CAP assessments will be measured. Subjects will be fit with binaural premium level receiver-in-the canal HAs (Phonak B90 or equivalent model at the start of the study) with 56 dB SPL gain receivers, using closed domes, and programmed to NAL-NL2 target gain, and randomly assigned to the groups.
Hearing Aid fitting: DNR
Digital noise reduction (DNR) set to maximum, MAD set to omnidirectional, and WDC set to linear
Device: Hearing Aid fitting
Subjects with hfPTAs ranging from 0-55 dB HL will be recruitedwith 100 persons self-reporting difficulty HIN (> 50% of the time), and 100 persons reporting little difficulty HIN (< 50% of the time) will be randomly assigned to one of five groups (n = 200) based on enabled HA features using an online random assignment tool. Unaided HIQ and HIN assessments will be conducted in the sound field, and baseline DPOAE and CAP assessments will be measured. Subjects will be fit with binaural premium level receiver-in-the canal HAs (Phonak B90 or equivalent model at the start of the study) with 56 dB SPL gain receivers, using closed domes, and programmed to NAL-NL2 target gain, and randomly assigned to the groups.
Hearing Aid fitting: Positive control
All hearing aid features enables
Device: Hearing Aid fitting
Subjects with hfPTAs ranging from 0-55 dB HL will be recruitedwith 100 persons self-reporting difficulty HIN (> 50% of the time), and 100 persons reporting little difficulty HIN (< 50% of the time) will be randomly assigned to one of five groups (n = 200) based on enabled HA features using an online random assignment tool. Unaided HIQ and HIN assessments will be conducted in the sound field, and baseline DPOAE and CAP assessments will be measured. Subjects will be fit with binaural premium level receiver-in-the canal HAs (Phonak B90 or equivalent model at the start of the study) with 56 dB SPL gain receivers, using closed domes, and programmed to NAL-NL2 target gain, and randomly assigned to the groups.
Hearing Aid fitting: Negative control
All hearing aid features disabled
Device: Hearing Aid fitting
Subjects with hfPTAs ranging from 0-55 dB HL will be recruitedwith 100 persons self-reporting difficulty HIN (> 50% of the time), and 100 persons reporting little difficulty HIN (< 50% of the time) will be randomly assigned to one of five groups (n = 200) based on enabled HA features using an online random assignment tool. Unaided HIQ and HIN assessments will be conducted in the sound field, and baseline DPOAE and CAP assessments will be measured. Subjects will be fit with binaural premium level receiver-in-the canal HAs (Phonak B90 or equivalent model at the start of the study) with 56 dB SPL gain receivers, using closed domes, and programmed to NAL-NL2 target gain, and randomly assigned to the groups.

What is the study measuring?

Primary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Regression analysis
Time Frame: June 2024
Regression analysis will be used to look for a correlation between measures of sensory cell and auditory neuron survival and speech recognition performance.
June 2024

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Sponsor

Steward St. Elizabeth's Medical Center of Boston, Inc.

Investigators

  • Principal Investigator: Mark Parker, PhD, Steward St. Elizabeth's Medical Center

Publications and helpful links

The person responsible for entering information about the study voluntarily provides these publications. These may be about anything related to the study.

General Publications

Helpful Links

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start (Actual)

January 1, 2013

Primary Completion (Actual)

December 12, 2019

Study Completion (Actual)

December 12, 2019

Study Registration Dates

First Submitted

January 29, 2013

First Submitted That Met QC Criteria

January 30, 2013

First Posted (Estimated)

January 31, 2013

Study Record Updates

Last Update Posted (Actual)

March 12, 2026

Last Update Submitted That Met QC Criteria

March 10, 2026

Last Verified

March 1, 2026

More Information

Terms related to this study

Keywords

Additional Relevant MeSH Terms

Other Study ID Numbers

  • 00652

Drug and device information, study documents

Studies a U.S. FDA-regulated drug product

No

Studies a U.S. FDA-regulated device product

No

product manufactured in and exported from the U.S.

No

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

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