Investigation of Anatomical Correlates of Speech Discrimination

Steward St. Elizabeth's Medical Center of Boston, Inc.186 enrolled

Overview

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.

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

186

Conditions

Sensorineural Hearing Loss

Interventions

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.

Eligibility

Sex: ALLMin age: 18 YearsMax age: 100 YearsHealthy volunteers:

Medical Language ↔ Plain English

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

Outcomes

Primary Outcomes

Regression analysis

Regression analysis will be used to look for a correlation between measures of sensory cell and auditory neuron survival and speech recognition performance.

Time frame: June 2024