Lateralisation and emotional expression regulation 1 RUNNING HEAD: Lateralisation and emotional expression regulation Linking children's neuropsychological processing of emotion with their knowledge of emotion expression regulation

Understanding of emotions has been shown to develop between the ages of four and ten years, however, individual differences exist in this development. Whilst previous research has typically examined these differences in terms of developmental and/or social factors, little research has considered the possible impact of neuropsychological development on the behavioural understanding of emotions. Emotion processing tends to be lateralised to the right hemisphere of the brain in adults, yet this pattern is not as evident in children until around the age of ten years. One hundred and thirty six children between five and ten years were given both behavioural and neuropsychological tests of emotion processing. The behavioural task examined expression regulation knowledge (ERK) for prosocial and self-presentational hypothetical interactions. The chimeric faces test was given as a measure of lateralisation for processing positive facial emotion. An interaction between age and lateralisation for emotion processing was predictive of children’s ERK for only the self-presentational interactions. The relationships between children’s ERK and lateralisation for emotion processing changes across the three age groups, emerging as a positive relationship in the 10-year-olds. The 10-years-olds who were more lateralised to the right hemisphere for emotion processing tended to show greater understanding of the need for regulating negative emotions during interactions that would have a selfpresentational motivation. This finding suggests an association between the behavioural and neuropsychological development of emotion processing.