Relationship between Behavioral Infant Speech Perception and Hearing Age for Children with Hearing Loss

Abstract

(1) Background: Research has demonstrated that early intervention for children who are hard-of-hearing (CHH) facilitates improved language development. Early speech perception abilities may impact CHH outcomes and guide future intervention. The objective of this study was to examine the use of a conditioned head turn (CHT) task as a measure of speech discrimination in CHH using a clinically feasible protocol. (2) Methods: Speech perception was assessed for a consonant and vowel contrast among 57 CHH and 70 children with normal hearing (CNH) aged 5-17 months using a CHT paradigm. (3) Results: Regardless of hearing status, 74% of CHH and 77% of CNH could discriminate /a-i/, and 55% of CHH and 56% of CNH could discriminate /ba-da/. Regression models revealed that both CHH and CNH performed better on /ba-da/ at 70 dBA compared to 50 dBA. Performance by hearing age showed no speech perception differences for CNH and children with mild hearing loss for either contrast. However, children with hearing losses ≥ 41 dB HL performed significantly poorer than CNH for /a-i/. (4) Conclusions: This study demonstrates the clinical feasibility of assessing early speech perception in infants with hearing loss and replicates previous findings of speech perception abilities among CHH and CNH.

Keywords: congenital hearing loss; early intervention; hearing aids; infant speech perception.

Figure 1

Time-amplitude waveforms and spectrograms for stimuli tested during the speech perception task. The top panel shows the /a/ and /i/ speech sounds for the vowel contrast and the bottom panel shows the /ba/ and /da/ speech sounds for the consonant.

Figure 2

Flow-chart representing the testing protocol consisting of two visits: visit 1 is shown in the upper half of the chart and visit 2 in the lower half of the chart.

Figure 3

(a) Performance on /a-i/ as a function of intensity (50, 60, and 70 dBA SPL) represented in columnar format. Each intensity column contains d’ scores for each of three hearing groups: normal hearing (NH; squares), mild hearing loss (HL-mild; circles), and moderate+ hearing loss (HL-moderate+; triangles). Empty symbols represent participants with an age at test less than nine months and filled symbols represent participants with an age at test greater than nine months. Regression lines for each of the hearing groups as a function of intensity level are plotted across the intensity columns (thick grey line = NL; dashed line = HL-mild; dotted line = HL-moderate+). (b) Performance on /ba-da/ as a function of intensity (50, 60, and 70 dBA SPL) represented in columnar format. Each intensity column contains d’ scores for each of three hearing groups: normal hearing (NH; squares), mild hearing loss (HL-mild; circles), and moderate+ hearing loss (HL-moderate+; triangles). Empty symbols represent participants with an age at test less than nine months and filled symbols represent participants with an age at test greater than nine months. Regression lines for each of the hearing groups as a function of intensity level are plotted across the intensity columns (thick grey line = NL; dashed line = HL-mild; dotted line = HL-moderate+).