Performance of the TENHL Test on Acclimated Users with Frequency Lowering Amplification
Maryrose McInerney, St John’s College of Liberal Arts and Sciences, Department of Communications Sciences and Disorders
Abstract: The purpose was to determine if performance on the TENHL(Threshold Equalizing Noise) test would have supported individual candidacy or impacted the prescription for frequency lowering amplification. Moore and colleagues created a clinically feasible strategy to measure off frequency listening, which is associated with diagnosis of cochlea dead regions in the IHCs and/or associated neurons. This study population had been previously binaurally fit, acclimated to, and reported exclusive use of either of two commercially available strategies of frequency lowering technology (spectral shifting/transposing or frequency compression) primarily due to their degree and configuration of hearing loss. Absolute & masked thresholds (TENHL) were measured in each ear. Verification of their binaural prescription was measured electroacoustically (2cc & REM). Validation measures, including subjective (IOI-HA) performance and speech discrimination & recognition in quiet (HRF) and in noise (QuickSINTM), were obtained. Results demonstrated half the participants to have positive TENHL results in one or both ears at one or more thresholds and one subject CNT w/TENHL due to HL. All 9 subjects reported benefits on IOI with their frequency lowering binaural fitting and no differences were observed between new and experience users of traditional HAs. All participants demonstrated speech recognition benefit in quiet and in noise. The TENHL identified one participant as positive for off frequency listening that would not have been identified by configuration alone. The TENHL was also negative for one participant that by configuration would support likelihood of off frequency listening and/or dead regions. Recommendations are made for future studies.