Estimation of auditory thresholds via a psychometric test based on the method of limits

Abstract

Psychoacoustics deals with studying human hearing abilities, such as sound detection, differentiation, and recognition. It is an important field, since hearing health is essential for well-being, directly influencing communication and social interaction abilities. Aiming to familiarize students with classical psychoacoustical methods, a didactic experiment was conducted in the Psychoacoustics course of the Federal University of Santa Maria's (UFSM) Acoustical Engineering program. The goal was to estimate the auditory thresholds of volunteers through a psychometric test based on the method of limits. The experiment was implemented in Matlab and the volunteers were exposed to audio signals reproduced via headphones. Initially inaudible, the signals gradually increased in amplitude, and participants were instructed to press a button when they heard the sound, which then began to decrease in intensity. The volunteer had to press the button again when the sound was no longer perceived, characterizing the ascending and descending thresholds. These measurements made it possible to estimate the average auditory threshold. Compared with reference curves from the literature, the results indicated the experiment's success. Ultimately, with a hands-on approach, students engaged with the activity and were able to better comprehend the topic, thus contributing to knowledge transfer and retention.