Computer use and letter knowledge in pre-school children: a population-based study.

AIM: To explore the link between pre-school children's general home computer use and their letter knowledge. METHODS: As part of the Early Language in Victoria Study, a community cohort of 1539 four-year-old children was tested on letter knowledge as well as on non-verbal intelligence, oral language, articulation and phonological awareness. Performance on these measures was examined in relation to parent-questionnaire responses exploring home literacy environment and the amount of time children spent using the computer. RESULTS: A positive correlation between computer use and letter knowledge was found, and this association was still evident after controlling for other cognitive and environmental factors known to predict the development of letter knowledge in young children. CONCLUSIONS: Greater computer use in pre-school children appears to have a positive association with emerging literacy development. Future research needs to examine the nature of that association.

Visual temporal processing in dyslexia and the magnocellular deficit theory: the need for speed?

A controversial question in reading research is whether dyslexia is associated with impairments in the magnocellular system and, if so, how these low-level visual impairments might affect reading acquisition. This study used a novel chromatic flicker perception task to specifically explore temporal aspects of magnocellular functioning in 40 children with dyslexia and 42 age-matched controls (aged 7-11). The relationship between magnocellular temporal resolution and higher-level aspects of visual temporal processing including inspection time, single and dual-target (attentional blink) RSVP performance, go/no-go reaction time, and rapid naming was also assessed. The Dyslexia group exhibited significant deficits in magnocellular temporal resolution compared with controls, but the two groups did not differ in parvocellular temporal resolution. Despite the significant group differences, associations between magnocellular temporal resolution and reading ability were relatively weak, and links between low-level temporal resolution and reading ability did not appear specific to the magnocellular system. Factor analyses revealed that a collective Perceptual Speed factor, involving both low-level and higher-level visual temporal processing measures, accounted for unique variance in reading ability independently of phonological processing, rapid naming, and general ability.

No evidence for a prolonged attentional blink in developmental dyslexia.

When two targets are presented within 500 msec of each other in rapid serial visual presentation (RSVP), the accuracy of second target identification is significantly reduced; a phenomenon termed the attentional blink. Recent studies have reported that children and adults with dyslexia exhibit deficits tied to the attentional blink; however, some ambiguity remains as to the nature of these impairments and how they relate to reading difficulties. The current study aimed to address these issues by examining attentional blink deficits in relation to orthographic, phonological, and fluency aspects of reading impairment. Twenty-two children with dyslexia were compared to 22 children with normally developing reading skills on an attentional blink task with results indicating the dyslexia group exhibited impaired performance regardless of the temporal lag between targets. These deficits appeared tied to general RSVP performance rather than a prolonged attentional blink and differences between groups fell below significance when the influence of general performance factors were controlled for.