Research on perceptual and cognitive capacities of the newborn has revealed that state variables typically interfere with or override the neonate's attentional and stimulus processing tendencies. This finding argues for the power of early state variables as behavioral determinants and, further, that neonatal state measures might provide good…

Uses findings from Seattle Longitudinal Study of adult cognitive development to assist discussion of event history analysis. Illustrates its application to data involving changes of states in individual behavior related to human aging. Describes hazard functions which permit assessment of future decline risk and prediction as to when individual…