Developmental delays in phonological recoding among children and adolescents with Down syndrome and Williams syndrome.
Williams syndrome can talk well yet still lack the inner sound code that aids memory, so pair verbal tasks with visual or gesture cues.
01Research in Context
What this study did
The team compared three groups: kids with Down syndrome, kids with Williams syndrome, and typically developing peers.
Everyone tried two short-term memory tasks that show whether we turn words into sounds in our head.
The study used a quasi-experimental design, so no one was randomly placed—each child already had their diagnosis.
What they found
Down syndrome kids used only one kind of sound trick, while Williams syndrome kids used none.
Typical kids used both tricks easily.
The result flips the old idea that strong talking skills in Williams syndrome mean normal memory strategies.
How this fits with other research
Poloczek et al. (2016) saw that teens with mild ID do use verbal rehearsal at their mental-age level.
Henrik’s team now shows Down syndrome kids only half-use it, and Williams kids skip it—so not all ID groups are alike.
Menghini et al. (2013) found bigger cerebellar vermis in Williams links to worse verbal short-term memory.
Together the papers say: poor phonological recoding in Williams has a brain base, not just a delay.
Why it matters
When you teach reading or memory games to a child with Williams syndrome, don’t bank on their chatty strength.
Give visual anchors, shorten sound chains, and check understanding without relying on echoic prompts.
For Down syndrome, expect partial help from sound cues but still add extra supports.
Want CEUs on This Topic?
The ABA Clubhouse has 60+ free CEUs — live every Wednesday. Ethics, supervision & clinical topics.
Join Free →Add picture cards or written keywords to any verbal list you ask a Williams child to remember.
02At a glance
03Original abstract
This study examined the development of phonological recoding in short-term memory (STM) span tasks among two clinical groups with contrasting STM and language profiles: those with Down syndrome (DS) and Williams syndrome (WS). Phonological recoding was assessed by comparing: (1) performance on phonologically similar and dissimilar items (phonological similarity effects, PSE); and (2) items with short and long names (word length effects, WLE). Participant groups included children and adolescents with DS (n=29), WS (n=25) and typical development (n=51), all with average mental ages around 6 years. The group with WS, contrary to predictions based on their relatively strong verbal STM and language abilities, showed no evidence for phonological recoding. Those in the group with DS, with weaker verbal STM and language abilities, showed positive evidence for phonological recoding (PSE), but to a lesser degree than the typical group (who showed PSE and WLE). These findings provide new information about the memory systems of these groups of children and adolescents, and suggest that STM processes involving phonological recoding do not fit with the usual expectations of the abilities of children and adolescents with WS and DS.
Research in developmental disabilities, 2016 · doi:10.1016/j.ridd.2016.03.012