Autor: |
Deiters KK; Stephenson and Stephenson Research and Consulting (SASRAC), Forest Grove, Oregon 97116, USA., Flamme GA; Stephenson and Stephenson Research and Consulting (SASRAC), Forest Grove, Oregon 97116, USA., Tasko SM; Stephenson and Stephenson Research and Consulting (SASRAC), Forest Grove, Oregon 97116, USA., Murphy WJ; National Institute for Occupational Safety and Health (NIOSH), Cincinnati, Ohio 45226, USA., Greene NT; United States (U.S.) Army Aeromedical Research Lab (USAARL), Fort Rucker, Alabama 36362, USA., Jones HG; United States (U.S.) Army Aeromedical Research Lab (USAARL), Fort Rucker, Alabama 36362, USA., Ahroon WA; United States (U.S.) Army Aeromedical Research Lab (USAARL), Fort Rucker, Alabama 36362, USA. |
Abstrakt: |
Middle ear muscle contractions (MEMC) can be elicited in response to high-level sounds, and have been used clinically as acoustic reflexes (ARs) during evaluations of auditory system integrity. The results of clinical AR evaluations do not necessarily generalize to different signal types or durations. The purpose of this study was to evaluate the likelihood of observing MEMC in response to brief sound stimuli (tones, recorded gunshots, noise) in adult participants (N = 190) exhibiting clinical ARs and excellent hearing sensitivity. Results revealed that the presence of clinical ARs was not a sufficient indication that listeners will also exhibit MEMC for brief sounds. Detection rates varied across stimulus types between approximately 20% and 80%. Probabilities of observing MEMC also differed by clinical AR magnitude and latency, and declined over the period of minutes during the course of the MEMC measurement series. These results provide no support for the inclusion of MEMC as a protective factor in damage-risk criteria for impulsive noises, and the limited predictability of whether a given individual will exhibit MEMC in response to a brief sound indicates a need to measure and control for MEMC in studies evaluating pharmaceutical interventions for hearing loss. |