Assessment of Novel Sound Changing Principles in Hearing Instruments to Determine Their Application - 2018_12

The sound quality ratings will be assessed with the aid of a Multi-Stimulus Test. The data, serving as the primary outcome measure, are collected in the laboratory and will use a continuous rating scale. The scale ranges from 0 "very bad" to 100 "very good" in increments of 1.

The data, serving as secondary outcome is a Signal to noise ratio (SNR) in decibel (dB) where a 50% speech reception threshold is reached. This outcome measurement will be carried out in the laboratory.

A dual task paradigm will be used in which the Oldenburg Sentence test in noise will be administered as a primary task, and the subject will manually track a point on a computerised elliptical track as a secondary task. The aim is to recall as many words from the presented sentence at a predefined SNR and track the point as accurately as possible at the same time. The SNR is set as the level at which a subject reaches a speech reception threshold of 80-90%. The data derived, serving as a secondary outcome measure, are a [%] of time on target and distance error from the target.

The ACALES procedure determines self-reported individual listening effort on a scale from "extreme effort" to "no effort" within a signal-to-noise ratio range that corresponds to individual subject perceptions.

The data, serving as a secondary outcome, are a set of points on a categorial scale (subjectively perceived listening effort) as a function of different SNRs.

A qualitative questionnaire with predefined questions and comment sections to gather information on individual perceptions regarding the comparison of two different hearing programs during different laboratory-based acoustic scenes. For details of the hearing aid settings, see study arms. The data collected from this questionnaire are scores on a continuous rating scale ranging from "hearing program A is much worse than hearing program B" to "hearing program B is much better than hearing program A" and any subjective comments given.

A 2 Interval - 2 Alternative Forced Choice task to measure the psychometric function of IPD detection with changing stimulus frequency. The data, serving as an outcome measure, is the individual interaural phase difference (IPD) frequency threshold (the frequency up to which 75% correct answers are given).

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.

The color-word- interference test ("Farb-Wort-Interferenztest nach J.R.Stroop" (version: "Günther Bäumler")) is a neuropsychological test of visual attention and interferer suppression and will be carried out in the laboratory. In the first trial, the subject has to read the names of colours written on a card as fast and accurately as possible. In the second trial, the subject has to name the colour ink of filled boxes on a card as quickly and accurately as possible. In the third trial, the names of colours are written on a card in a dissimilarly coloured ink. The participant must read aloud the written words, whilst ignoring the colour of the ink. The data, serving as an outcome measure, are time-to-complete the sets in seconds.