Can Closed-Set Word Recognition Differentially Assess Vowel and Consonant Perception for School-Age Children With and Without Hearing Loss?

Abstract

Vowels and consonants play different roles in language acquisition and speech recognition, yet standard clinical tests do not assess vowel and consonant perception separately. As a result, opportunities for targeted intervention may be lost. This study evaluated closed-set word recognition tests designed to rely predominantly on either vowel or consonant perception and compared results with sentence recognition scores. Participants were children (5-17 years of age) and adults (18-38 years of age) with normal hearing and children with sensorineural hearing loss (7-17 years of age). Speech reception thresholds (SRTs) were measured in speech-shaped noise. Children with hearing loss were tested with their hearing aids. Word recognition was evaluated using a three-alternative forced-choice procedure, with a picture-pointing response; monosyllabic target words varied with respect to either consonant or vowel content. Sentence recognition was evaluated for low- and high-probability sentences. In a subset of conditions, stimuli were low-pass filtered to simulate a steeply sloping hearing loss in participants with normal hearing. Children's SRTs improved with increasing age for words and sentences. Low-pass filtering had a larger effect for consonant-variable words than vowel-variable words for both children and adults with normal hearing, consistent with the greater high-frequency content of consonants. Children with hearing loss tested with hearing aids tended to perform more poorly than age-matched children with normal hearing, particularly for sentence recognition, but consonant- and vowel-variable word recognition did not appear to be differentially affected by the amount of high- and low-frequency hearing loss. Closed-set recognition of consonant- and vowel-variable words appeared to differentially evaluate vowel and consonant perception but did not vary by configuration of hearing loss in this group of pediatric hearing aid users. Word scores obtained in this manner do not fully characterize the auditory abilities necessary for open-set sentence recognition, but they do provide a general estimate.