The effects of changes in stimulus properties on acoustic stapedius reflex response: a systematic review

Background The acoustic stapedius reflex is formed by the contraction of the stapedius muscle in the middle ear cavity when a loud sound is given to both ears. Changes in properties such as the intensity, frequency, duration, and speed of stimulus affect reflex responses. Methods As a result of the literature review conducted between 2005 and 2020, 2846 articles were reviewed and 30 articles evaluating the effects of stimulus changes on acoustic reflex responses were included in the study. Main text In the studies reviewed, it was observed that lower threshold values were obtained by using noise as a stimulus instead of pure sound. Different results were found regarding the duration and frequency of the stimulus. It has been reported that stimulus frequency does not have a significant effect on acoustic reflex delays and the acoustic stapedius reflex threshold increases in the presence of opposite side noise. Conclusion As a result of the studies reviewed, it was seen that the changes in many properties of the stimulus that activate the middle ear muscles affected the reflex response.