Is one ear good enough? Unilateral hearing loss and preschoolers’ comprehension of the English plural

Purpose: The plural is one of the first grammatical morphemes acquired by English-speaking children with normal hearing (NH). Yet, those with hearing loss show delays in both plural comprehension and production. However, little is known about the effects of unilateral hearing loss (UHL) on children's acquisition of the plural, where children's ability to perceive fricatives (e.g., the /s/ in cats) can be compromised. This study therefore tested whether children with UHL were able to identify the grammatical number of newly heard words, both singular and plural.

Method: Eleven 3to 5-year-olds with UHL participated in a novel word two-alternative forced choice task presented on an iPad. Their results were compared to those of 129 NH 3to 5-year-olds. During the task, children had to choose whether an auditorily presented novel word was singular (e.g., tep, koss) or plural (e.g., teps, kosses) by touching the appropriate novel picture.

Results: Like their NH peers, children with UHL demonstrated comprehension of novel singulars. However, they were significantly less accurate at identifying novel plurals, with performance at chance. However, there were signs that their ability to identify novel plurals may improve with age.

Conclusion: While comparable to their NH peers at identifying novel singulars, these results suggest that young children with UHL do not yet have a robust representation of plural morphology, particularly on words they have not encountered before.