Optimising word learning in post-secondary students with Developmental Language Disorder: The roles of retrieval difficulty and retrieval success during training

Abstract

Purpose

Learning words to the level that they can be readily retrieved and produced can be challenging. The primary aim of the current study is to determine how retrieval difficulty, based on the level of cuing provided, and retrieval success during training relate to the phonological precision with which words are produced after a delay.

Method

We performed additional analyses on data from McGregor, Gordon, Eden, Arbisi-Kelm, & Oleson, (Encoding deficits impede word learning and memory in adults with Developmental Language Disorders. Journal of Speech, Language, and Hearing Research, 60, 2891–2905) in which post-secondary students with Developmental Language Disorder (DLD, n = 23) and typical development (n = 25) were trained on words via free and cued recall practice and tested 24-h later.

Results

Training via free recall led to more precise productions after the delay than training via cued recall for both groups. Additionally, the number of successful retrievals during training positively predicted retrieval after the delay. Furthermore, the precision of participants’ last production and worst production of each word were the best predictors of production precision after the delay.

Conclusion

To optimally support encoding and delayed retrieval, students with and without DLD should utilise free recall practice. Additionally, words should be studied until they are successfully retrieved multiple times at a high level of phonological precision to support delayed retrieval.

Keywords:

• testing effect
• retrieval practice
• developmental language disorder

Declaration of interest

There were no competing interests for the authors at the time of publication.

Notes

1 Historically this disorder has been referred to by a variety of terms, most notably Language Impairment and Specific Language Impairment. To address the problem of the various terms being used for the same disorder, Bishop organised a panel of 59 experts across ten fields (Bishop, Snowling, Thompson, & Greenhalgh, 2017). This panel decided on the term Developmental Language Disorder.

2 Within the clinical word-learning literature, free recall trials typically involve showing the participant a trained referent and asking the participant to name it. Cued recall trials typically involve asking the participant to name a referent when they are given cues to the target word form, such as the first phoneme or first syllable of the word. This differs from the retrieval-based learning literature. Within this literature, a free recall trial typically involves the participant writing down or verbally producing everything that he or she remembers about the target material without any of the visual or verbal information that was presented during study. Whereas a cued recall trial involves providing a cue such as a visual image of each trained word-referent pair, or the target word that participants are then asked to define. For the current manuscript, we utilize the labels free recall and cued recall in a manner that is consistent with the clinical literature and consistent with McGregor, Gordon, et al. (2017). However, the reader should note that our free recall trials include an important cue, a visual presentation of the referent; and the cued recall trials include two important cues, a visual presentation of the referent and the first syllable of the target word form.

3 One participant with typical development was excluded from McGregor, Gordon, et al. (2017) because she did not complete the last session, a visual-world paradigm task conducted one week after training. Thus, McGregor, Gordon et al. (2017) includes data from 24 individuals with TD in their analyses. However, because we are not including data from the last session, we conducted the current analyses with 25 individuals with TD.

4 All words included in McGregor, Gordon, et al. (2017) had stress placed on the first syllable and the second syllables only included reduced vowels (i.e. all second syllable vowels were lax and centralised). Given these characteristics of the forms, it is unclear if individuals with DLD would demonstrate a similar weakness with learning the second syllable when learning forms with different characteristics. Through future research we can determine the specific characteristics of word forms that contribute to specific learning outcomes for individuals with DLD.