This study examined contributions of maternal personality and infant temperament to infant vocabulary and cognitive development both directly and indirectly through parental stress. Participants were recruited at birth and included 63 infant twin pairs and their mothers. Assessments were completed at 6, 9, 12, and 18 months of age and included…

Examined whether early differences in stress reactivity were related to self-recognition at 18 months. Found that self-recognition was related to greater cortisol response and less rapid quieting at 6 to 18 months, whereas cortisol and quieting responses of 2- to 4-month-olds did not differentiate self-recognizers and non-self-recognizers,…

Investigated whether, in a sample of 30 infants, anger could reliably be observed in facial expressions as early as seven months of age. Also considered was the influence of several variables on anger responses: infants' familiarity with the frustrator, repetition of trials, and sex of the child. (Author/RH)

Examines strategies for studying individual differences in infant behavior from the standpoints of the distinction between individual differences and developmental function and the need to study change with multivariate techniques. These themes are applied to the study of mental development, behavior genetics, temperament, and attachment. (RJC)

Tests of conditionability in infants were used in a longidudinal study of 32 subjects in the first year of life. The research was based on Eysenck's hypothesis that conditionability i s a unitary factor related to introversion-extroversion and attention span. The objective of the investigators was to devise a battery of conditioning tasks…

This document consists of four research reports and one research note focusing on several aspects of the cognitive and emotional development of young children. The first article explores two theories of the relationship between cognition and emotion, reporting on an investigation of that relationship in a simple learning task involving 60 Japanese…