Current opinions on audiovisual integration in typical & atypical reading development (COAIR): How specific is the paired associate learning deficit in dyslexia to cross-modal working memory?

Purpose

Proficient reading requires the ability to create, store, and retrieve cross-modal bindings (e.g., letter and letter-sound mappings) from memory. This paired associate learning – or ‘binding’ - ability is shown to be impaired in individuals with atypical reading skills, such as those with developmental dyslexia. However, research to date has not addressed the specificity of this deficit.


Method

Here, we sought to ascertain the specificity of a cross-modal binding deficit in dyslexia, in the absence of verbal output demands, via a novel manipulation of the well-known n-back paradigm. We compared N=48 adults with and N=48 adults without dyslexia on two uni-modal conditions (visual: shape-colour; auditory: word-voice) and a cross-modal condition (shape-word). Accuracy and RTs reflected participant’s ability to detect whether a given item in a stream of items was identical to that presented on trial N-2.


Results

We predict that if dyslexia in adulthood is characterised by a specific cross-modal binding deficit, adults with dyslexia will be less accurate in the cross-modal condition compared with the uni-modal conditions, whereas no such difference in accuracy across conditions will appear in the adults without dyslexia.


Conclusions

This paradigm – in removing verbal task demands, and in better equating processing difficulty across conditions – will elucidate whether dyslexia involves a specific cross-modal binding deficit, thus speaking to an important debate in reading research: the nature of paired associate learning deficits in developmental dyslexia.