The two functions of imitation in the second year of life: A longitudinal study.

Infant imitation serves a cognitive and a social function. As part of their temperament, infants' attention and social orientation mirror these two functions. This longitudinal study investigated the development of the two functions within the second year of life in German infants ( = 136, 74 female), using standardized tests at the ages of 12, 18, and 24 months, conducted in 2018 and 2019.

Stability and structure of infant and toddler temperament in two longitudinal studies in Germany.

The present study investigated the factor structure and longitudinal stability of infant and toddler temperament measured with the Infant Behavior Questionnaire-Revised (IBQ-R) and the Early Childhood Behavior Questionnaire (ECBQ) in two German samples. Since the few studies using the German IBQ-R failed to replicate the commonly assumed three factors of infant temperament, another exploration of its factor structure was necessary. Whereas previous stability measurements are usually based on groups with relatively large age ranges, we investigated stability between concrete ages.