Yearly cognitive tests were administered to adoptive and nonadoptive siblings between one and seven years of age and identical and nonidentical twins between one and three years. Results indicated that genetic influences are a source of continuity and change in mental development, whereas shared and nonshared environmental effects contribute to…

Reviews bases for contemporary discontinuity theories of mental development, presents findings that support alternative proposition of continuity and scrutinizes assessment methods from which these continuity results derive. Also offers several models that help explain the continuity findings, and argues that individual differences in mental…

Examined the joint and unique predictive significance of emergent literacy skills for later emergent literacy skills and reading in two samples of preschoolers. Structural equation modeling revealed significant developmental continuity of these skills, particularly for letter knowledge and phonological sensitivity from late preschool to early…