The sensitivity of Doppler imaging to line profile models

Abstract

Performance-intensity (PI) functions for Pediatric Speech Intelligibility (PSI) test materials were obtained in 40 normal-hearing children between 3 and 6 yrs of age. PSI messages were monosyllabic words and sentences presented in quiet and in the presence of a competing speech message. The message-to-competition ratio was constant across intensity levels: +4 dB (words) and 0 dB (sentences). Maximum speech intelligibility scores were 100% correct in all children for all conditions. The steepness of the PSI-PI functions, defined by the intensity range yielding performance between 20 and 80%, ranged from 8 to 12 dB. Threshold levels (50% correct) ranged from 21 to 26 dB SPL. With one exception, chronological age did not significantly influence the steepness of PSI-PI functions. The exception was the increasing steepness increasing age noted for sentences in competition. A significant chronological age developmental trend was noted for all speech threshold results.