PRINCE22 System Complete Performance Study

The Concurrent OLSA test (CC-OLSA) is a speech recognition test with three turn-taking talkers presenting sentences of the Oldenburg sentences test at fixed signal-to-noise ratios.

CC-OLSA is the only one-talker-at-a-time speech test that is sensitive at the desired SNR and uses sentences with an intelligibility function with slopes of 10-17 %/dB.

The measure of the subjective speech recognition threshold is an alternative procedure to evaluate the subjective speech intelligibility in different listening conditions. The subjective speech recognition threshold is defined as the speech presentation level of running speech needed to just follow conversation. Subjects have to adjust the presentation level of speech so that they are just able to understand the speech, using a slider on a touch screen. This adjustment is repeated 10 times. Each adjustment results in a value for the subjective speech recognition threshold in dB SNR. The outcome measure is the mean value of the 10 repetitions. The HEISS-Test will be repeated four times for the secondary objective: test for 2 test conditions (Reference, novel approach) against 2 target directions (better ear side, back).

This test uses a dual-task-paradigm assessing vigilance for auditory and visual triggers concurrently. The primary task is to listen to a novel (Harry Potter) and respond on two trigger words by pressing the appropriate button (one in each hand). The secondary task is to observe a monitor showing a sequence of random signs and respond on a target sign by pressing both buttons. The test includes at least 100 triggers (50 auditory, 50 visual) and takes 10 minutes per condition (side vs. back; novel approach vs. reference; 40 minutes in total). The multitask test will be repeated four times for the secondary objective: 2 conditions (Refrence, novel approach) against 2 target directions (better ear side, back). Following data are provided from each multitask Test measure: (1) subjective rating of the perceived ability to perform the visual and the auditory test simultaneously. (2) reaction times to auditory and visual tasks, and (3) accuracy.

In addition to the tests mentioned above a subjective assessment will be used to determine the subjective perception as this measure is often a good indication for clinical relevance.

For this purpose, the same speech material as used in the HEISS-test is presented by a loudspeaker in the same noisy environment as in the other three tests. The subjects rate his/her perception of the presented speech using a questionnaire on the dimensions "listen effort and speech intelligibility". The subject will rate his perception on the 100 point scale with pencils with different colors to get either absolute and relative ratings.

The subjective assessment will be repeated four times for the secondary objective: 2 test conditions (Rference and novel approach) against 2 target directions (better ear side, back). Following data are provided from assessment: rating on a 100-point scale per condition and per dimension.