DiLalla, L.F., & Bishop, E G (1997). Genetic and maternal influences on infant/toddler task behaviors. Paper presented to the Behavior Genetics Association, July, Toronto, Canada. Abstracted in Behavioral Genetics, 27, 587-588.

Examination of differential maternal treatment of infant twins can elucidate our understanding of some of the factors contributing to early attention behaviors, which may be important precursors to later measures of intelligence as well as social development. A prior report (DiLalla, L.F., & Bishop, E G, 1996, Behav. Genet. 26, 535-542) showed that global measures of task orientation and enthusiasm in 7 and 9 month olds were influenced primarily by unique environment as well as shared environment and that there was little differential parental treatment by zygosity. Further exploration of this sample longitudinally at 14, 24, and 36 months of age utilizes a model whereby unique environment and additive genetic influences as well as maternal behaviors predict child behaviors. LISREL models showed significant effects of both unique environment (average e² = 44) and maternal behaviors (average B = .63) at each age. Additionally, a heritable component was significant at 7, 9, and 24 months (average h² = .26) but not at 14 or 36 months. Maternal behaviors could be related to child attention behaviors through genetic and/or environmental pathways but are clearly important correlates of child behaviors.