Phonemic discrimination and reproduction in 4-5-year-old children: Relations to hearing

The long-term objective of this research is to highlight the importance of speech perception assessment in children with developmental language disorder (DLD), and to investigate how hearing contributes to speech and language skills. As a first step in fulfilling this aim, the present study explored relations between phonemic discrimination and reproduction, and sensitive measures of hearing in young healthy children.

The American Listen-Say test was developed and served as speech perception tool. This test reports speech discrimination of phonemic contrasts quantitatively for both quiet and in noise conditions, along with reproduction scores, all measured within one session. Speech tokens were perceptually homogenized in noise. Forty-one 4-5-year-old American children participated. Phonemic discrimination (quiet and speech shaped noise) and phonemic reproduction, audiometric thresholds in the conventional (1-8 kHz) and extended high frequency (EHF; 10-16 kHz) range, and distortion product otoacoustic emissions (DPOAEs) were examined.

All children had normal hearing thresholds within the conventional range (mean PTA bilaterally 8.6 dB HL). Ten (24.3%) of the children had elevated EHF thresholds (> 20 dB HL) for one or more frequencies or ears, and six (14.6%) had DPOAE signal to noise ratios (SNR) < 6 dB. EHF thresholds and DPOAE SNRs were significantly associated. Children's phonemic discrimination was impaired in noise, relative to quiet. There was a moderate, significant correlation between overall phonemic discrimination in noise and EHF audiometric thresholds.

Overall, the present study showed that sensitive hearing measures enabled the detection of subtle hearing difficulties in young healthy children. In particular, phonemic discrimination in noise showed associations with hearing. Implications of including sensitive hearing measures in children with DLD are discussed.