Assessment of Novel Sound Changing Principles in Hearing Instruments to Determine Their Application - 2019_33

Assessment of Novel Sound Changing Principles in Hearing Instruments to Determine Their Application - 2019_33

Participants will complete a listening task in a simulated reverberant environment. Participants are seated and instructed to look at a fixation cross while a sentence is played. Sentences are varied with respect to their speech rate. While listening to the sentences participant's pupil dilation is measured by means of pupillometry which is a non-invasive physiological measurement. Participants are asked to repeat back the sentences loud. At fixed intervals, subjective ratings are collected by asking participants to move an on-screen slider using a game controller. Two hearing aid programs will be compared, one intended for speech perception in quiet and the other to reduce reverberation in reverberant environments. The study is designed as factorial, with 2 speech rates, 2 room simulations and 2 hearing aid programs. The same conditions will be re-tested once after a minimum of one day. A pilot study will determine appropriate speech rates by applying a different factorial, with 4 speech rates, 2 room simulations and 1 hearing aid program. Participants complete all conditions (within-subjects) in one experimental sessions that lasts around 1 hour.

Each participant will be fitted with the 2 different Sound Changing principles on the same hearing aid, saved to 2 manual programs (ensures exact same hearing loss compensation for each intervention). Reverberation Canceller principle is a sound processing algorithm to remove reverberation from a speech signal to improve the speech intelligibility and comfort. The active comparator condition is without Reverberation Canceller principle enabled.

Each participant will be fitted with the 2 different Sound Changing principles on the same hearing aid, saved to 2 manual programs (ensures exact same hearing loss compensation for each intervention). Reverberation Canceller principle is a sound processing algorithm to remove reverberation from a speech signal to improve the speech intelligibility and comfort. The experimental condition applies the Reverberation Canceller and is predicted to provide a benefit in reverberant room simulations.

Pupil dilations will be recorded from the participant during the performance of the auditory tasks. Analyses will be carried out relative to the pre-trial baseline (measured one second prior to the onset of the stimulus), in order to account for differences in baseline physiological activity. It is planned to analyze event-related-pupil-dilations.

1. Words recalled correctly: words repeated back by participants are logged and the percentage of words recalled correctly calculated.

Subjective ratings: using a game controller, participants rate the difficulty of the sentences and listening effort on a visual analog scale. The scale is continuous and ranges from minimal to maximal difficulty/effort. The position of the cursor on the scale is then used to calculate a percentage from 0-100% difficulty/effort.

The Trail Making Test is a neuropsychological test of visual attention and task switching. It consists of two parts in which the subject is instructed to connect a set of 25 dots as quickly as possible while still maintaining accuracy. The data, serving as an outcome measure, are time-to-complete the set in seconds

Inclusion Criteria: Healthy outer ear (without previous surgical procedures) Ability to fill in a questionnaire conscientiously Informed Consent as documented by signature Mild-Moderate/Severe (N2-N4) hearing loss Exclusion Criteria: Contraindications to the MD in this study, e.g. known hypersensitivity or allergy to the investigational product Limited mobility and not in the position to attend weekly appointments Limited ability to describe listening impressions/experiences and the use of the hearing aid Inability to produce a reliable hearing test result Massively limited dexterity Known psychological problems Known central hearing disorders