The encoding of word forms into memory may be challenging for college students with developmental language impairment

Abstract

Purpose: To describe the word-learning problems characteristic of developmental language impairment (LI).

Method: College students with LI (n = 39) or normal language development (ND, n = 40) attempted to learn novel word forms. Training for half of the words was meaning-focused; training for the other half was form-focused. Form recognition and stem completion tasks administered immediately after training tapped encoding of the lexical configuration and a repetition of the stem completion task one week later tapped consolidation. A visual world paradigm tapped lexical engagement.

Result: At the immediate post-test, the LI group was poorer at recognition and completion of word forms than their ND peers, suggesting a deficit in encoding the lexical configuration. However, the gap between the LI and ND groups in stem completion did not grow over the week, suggesting intact consolidation. Form-focused training yielded better performance than meaning-focused training at immediate- and one week tests. For both groups, newly trained words slowed the recognition of familiar English words, revealing lexical engagement.

Conclusion: The encoding of word-form configurations is challenging for some, but not all, college students with LI. Training that encourages a focus on the form may be a useful part of vocabulary intervention for those affected.

Keywords:

• Developmental language impairment
• word learning
• memory

Acknowledgements

We thank the participants for their generosity and Efthymia Kapnoula and Katherine Gordon for feedback on an earlier version of this manuscript. This work was supported by NIH-NIDCD [grant number DC011742].

Declaration of interest

The authors report no conflicts of interest. The authors alone are responsible for the content and writing of the paper.