Abstract
Individuals with intellectual disability (ID) exhibit deficits in both selective attention and visual short-term memory (VSTM). However, whether attentional deficits directly constrain VSTM performance in ID remains unknown. Here, we examined the interplay between these two processes in ID and their correlates with fluid intelligence across individuals with varying levels of intellectual functioning. Nineteen adults with ID and twenty-two chronologically matched neurotypical adults (TDA) carried out the Attentional Orienting Task (AOT), in which they briefly viewed a memory array, followed by a probe and indicated whether the probe was previously presented in the memory array. Visuospatial attention cues were shown before (pre-cues) or after (retro-cues) the memory array to assess attentional orienting in service of VSTM encoding and maintenance, respectively, compared to neutral, baseline attention cues. Additionally, participants completed Raven's 2, a non-verbal reasoning test. TDA adults outperformed individuals with ID across all conditions. Importantly, while TDA demonstrated clear attentional orienting benefits in service of VSTM, individuals with ID showed no cueing benefits either before encoding into VSTM or during VSTM maintenance. Correlation and regression analyses showed that attentional orienting abilities predicted fluid intelligence beyond baseline VSTM performance. Current results show for the first time that attentional deficits constrain VSTM performance in ID, whereas individual differences in attentional orienting in service of VSTM predict non-verbal reasoning abilities. These findings speak to the overall functioning difficulties individuals with ID face and highlight the need to consider the dynamic relation between these cognitive processes when designing assessments and interventions for intellectual disabilities.