Memory and speed: their role in the relation of infant information processing to later IQ.

This study examined the extent to which memory and processing speed accounted for relations we had found earlier between infant information processing and childhood IQ. The measures of speed and memory were obtained when the children were 11 years of age using paper-and-pencil tasks and an extensive battery of computer-administered tasks. The relations of 7 months visual recognition memory and 1 year cross-modal transfer to 11 year IQ were both substantially reduced with statistical control of factors derived from these measures. These results suggest that speed and memory underlie some of the infant-childhood continuities in cognition. Path and structural equation modeling indicated that the significant pathways from 7 month visual recognition memory to 11 year IQ were both direct and indirect, the indirect paths going through memory and speed.