Vocabulary and working memory in children fit with hearing aids

To determine whether children with mild-to-moderately severe sensorineural hearing loss (CHL) present with disturbances in working memory and whether these disturbances relate to the size of their receptive vocabularies.

Children 6 to 9 years of age participated. Aspects of working memory were tapped by articulation rate, forward and backward digit span in the auditory and visual modalities, Corsi span, parent surveys, and a sequential encoding task. Articulation rate, digit spans, and Corsi spans were also administered in low-level broadband noise.

CHL and children with normal hearing (CNH) demonstrated auditory advantage in forward serial recall. CHL demonstrated slower articulation rates than CNH, but similar memory spans. CHL with poor executive function presented with poorer performance on the Corsi span task. The presence of background noise had no effect on performance in either group. CHL presented with significantly smaller receptive vocabularies than their CNH peers. Across groups, receptive vocabulary size was positively correlated with digit span in quiet, Corsi span in noise, and articulation rate.

In the presence of mild-to-moderately severe hearing loss, children demonstrated resilient working memory systems. For all children, working memory and vocabulary were related; that is, children with poorer working memory had smaller vocabulary sizes.