By the end of the 1970s, about 50 years of research had shown fairly clearly that prediction coefficients from measures of infant behaviour to later measures of intelligence in childhood were so low as to indicate that, except in extreme cases such as severe subnormality, the early measures had no predictive validity.1 2 From about this time, however, researchers began to question the nature and validity of the infant tests on which these findings were based. It was argued that the ‘mental scales’ on these tests primarily measured perceptual and motor development, rather than mental or cognitive growth, and there is little reason to expect measures of such abilities to predict later IQ.3 4

Accordingly, the search began for cognitive or information processing measures of infant performance which might more reasonably be considered to tap abilities that are similar to, and may be predictive of, the abilities measured by the childhood intelligence tests. A major focus of this research has been on measures of visual information processing and attentiveness, and it has become clear that a moderate degree of predictability may be possible, leading some to the view that the ‘promise of greater predictive accuracy using recognition memory and habituation rate represents one of the most exciting contemporary fields of inquiry’.5