Speed of sensory information processing has long been recognized as an important characteristic of global intelligence, though few studies have concurrently investigated the contribution of different types of information processing to nonverbal IQ in children, nor looked at whether chronological age vs. months of early schooling plays a larger role. Thus, this study investigated the speed of visual information processing in three tasks including a simple visual inspection time (IT) task, a visual-verbal processing task using Rapid Automatic Naming (RAN) of objects as an accepted preschool predictor of reading, and a visuomotor processing task using a game-like iPad application, (the “SLURP” task) that requires writing like skills, in association with nonverbal IQ (Raven’s Coloured Progressive Matrices) in children (n = 100) aged 5–7 years old. Our results indicate that the rate and accuracy of information processing for all three tasks develop with age, but that only RAN and SLURP rates show significant improvement with years of schooling. RAN and SLURP also correlated significantly with nonverbal IQ scores, but not with IT. Regression analyses demonstrate that months of formal schooling provide additional contributions to the speed of dual-task visual-verbal (RAN) and visuomotor performance and Raven’s scores supporting the domain-specific hypothesis of processing speed development for specific skills as they contribute to global measures such as nonverbal IQ. Finally, RAN and SLURP are likely to be useful measures for the early identification of young children with lower intelligence and potentially poor reading.

Objective: The primary aim of the present study was to examine the predictive contribution of age and speed of visual processing measures to the determination of visual working memory (VWM) and auditory working memory (AWM) in children aged 5–7 years. Method: The present study has used structural equation models (SEM) for determination of speed of visual processing measures (visual inspection time, visual–verbal rapid automatic naming of objects, and a visuo-motor game-like iPad application) to working memory (WM) using forward and backward visual and auditory verbal digit span (FDS and BDS, respectively) tasks as the dependent working memory (WM) measures. Results: Analysis of variance revealed that visual and auditory FDS and BDS improved significantly with school grade being consistent with the notion that VWM and AWM are experimentally dissociable cognitive domains that develop at differential rates in early years of schooling as the child becomes progressively more familiar with the translation of visual symbols into their verbal equivalents. Furthermore, our SEM does not support Baddeley’s multicomponent model of working memory, with visual information processing significantly contributing to VWM but not to AWM in primary school-aged children. Conclusions: Our findings provide evidence of continuing WM development paralleling brain maturation of children. Overall, our results support a developmental cognitive neuroscience approach to WM development.

Conscious, goal-directed behaviours in adults require attention and access to working memory (WM) and utilize the same visually driven parieto-frontal neural networks of the brain. Logically, the development of this goal-directed network must also underpin all learning and cognitive maturation.in children. Thus, we sought to systematically review the current literature relating to development of cognitively defined constructs of attention and WM in children from birth to 7 years old from the perspective of functional brain development. Abstracts were extracted from electronic databases (Medline, PsycINFO, EMBASE, Science Direct, and PubMed) and 24/4212 studies were identified as meeting the inclusion, risk of bias and validity criteria. Only 3/24 studies investigated visual attention in infants using preferential looking tasks and monitoring of eye movements. Twenty-one out of the 24 studies investigating attention in children aged 2+ years used visually based tasks that required participants to possess the ability to visually and auditorily attend to the presented stimuli, have adequate receptive language to understand and remember the verbal instructions, and WM and executive functions to respond verbally or manually. All studies found attention and WM to be significantly related. Few studies controlled for the inherent maturation of assumed cognitive skills or motor development, though a number have measured time required to perform a task. Further, there are very few studies in the literature where concurrent psychophysical, gaze tracking or brain imaging techniques have been used to investigate the functional neuroanatomy of attention and working memory networks in young children. Future exploration with more biologically and cognitively integrated paradigms are needed to clarify relationships between each aspect of attention and WM (verbal and visual), especially with respect to the timing and source localization of the temporal trajectory of neural activation during task completion.