Sources of errors in nonword repetition in children with reading and/or language impairment: Encoding vs. retrieval

Sources of errors in nonword repetition in children with reading and/or language impairment: Encoding vs. retrieval

First Author: Anna Ehrhorn -- University of South Carolina
Additional authors/chairs: 
Suzanne Adlof; Daniel Fogerty
Keywords: Nonword Repetition, Dyslexia, Language impairment, Phonological processing, children
Abstract / Summary: 

Purpose: Children with reading or language impairment frequently show poor nonword repetition (NWR), but the source of NWR difficulties has been debated. We build on a prior study by Bishop and colleagues (2012) to examine two possible sources of phonological difficulty, encoding and retrieval, within a larger sample that controls for the co-occurrence of DLD and dyslexia and includes multiple measures.

Method: Participants include 7-9-year old children in four groups: DLD-only (n=39), dyslexia-only (n=22), DLD+dyslexia (n=40), and TD (n=55). In the encoding task, participants repeated the same three multi-syllable nonwords across a series of five trials. Following an unrelated distractor task, retrieval was measured with an old/new recognition memory task and a delayed final repetition of the same nonwords.

Results: Preliminary analyses of the encoding task indicate significant effects of group and trial number with no interaction. The TD group showed the highest level of accuracy, the DLD+dyslexia group showed the lowest accuracy, and DLD-only and dyslexia-only groups performed in the middle. Across groups, there was significant improvement in accuracy between the first repetition and all subsequent repetition trials. All groups maintained repetition accuracy between the fifth repetition and the delayed final repetition. Descriptively, group differences for the old/new recognition memory task and the delayed final repetition mirror those of the encoding task.

Conclusions: Results suggest that NWR difficulties for all groups are primarily encountered upon initial encoding and persist across multiple repetitions and during subsequent retrieval. Theoretical implications and directions for future research will be discussed.