Effects of self-generated noise on quiet threshold by transducer type in school-age children and adults

Abstract

This study tested the hypothesis that higher levels of self-generated noise in children results in larger child-adult differences for the detection of low-frequency sounds when testing is conducted using transducers associated with a pronounced occlusion effect. Detection thresholds were measured at 125, 250, 500, and 1000 Hz using standard clinical procedures with supra-aural headphones, insert earphones, or a loudspeaker. Probe microphone recordings were made during testing with each transducer. Listeners were 4.5- to 11-year-olds, and adults. Preliminary results are consistent with the a priori hypothesis. For all listeners, thresholds at 125 and 250 Hz were highest with supra-aural headphones and lowest with free-field presentation. This transducer effect was most pronounced for younger children. Child-adult differences were smaller at 500 and 1000 Hz, an observation consistent with reduced effects of self-generated noise with increasing frequency. Trial-by-trial analysis of probe microphone recordings will be presented.