A child’s word
knowledge or vocabulary supports oral and written language learning. Children
with developmental language disorders (DLD; also known as specific language
impairment) have difficulty learning new vocabulary in naturalistic contexts
because they need more exposures to learn new words and tend to forget the
words they just learned. A large body of research has shown positive effects on
learning from an approach called distributed learning, which involves spacing
out learning episodes with longer intervals between them.
This study
looked at whether such a spaced learning approach would be effective for vocabulary
learning in children with DLD. Specifically, the researchers examined how
vocabulary learning was influenced by increasing the number of exposures
(frequency effects) and spreading out the exposures over time (spacing effects)
for children with and without DLD. To answer this question, researchers taught
four nonwords to preschool-aged children with either 12 or 18 exposures spread
out over either 1 or 4 days. With this study design, each word was taught using
a different schedule (i.e., 12 exposures on 1 day, 12 exposures over 4 days, 18
exposures on 1 day, or 18 exposures over 4 days).
Overall, results
showed that word learning among children with typical language skills was the
same regardless of number or spacing of exposures. For children with DLD,
however, word learning was better when the exposures were spread out over 4
days. There was also a frequency effect for children with DLD, but only for
words taught on a single day. If the exposures were spread out over 4 days, the
number of exposures didn’t seem to matter. Finally, testing a week after the
completion of training showed poorer retention for children with DLD when they
were asked to name the target words. In comparison, children with typical
language showed no evidence of forgetting. These findings suggest that children
with language impairment may benefit from spaced vocabulary learning rather
than from exposures en masse.
Blogger: Laura Pauls is a PhD student in
the Language and Working Memory Lab
