ABSTRACT: We investigated whether brain electrical activity during early  childhood was associated with anxiety symptoms and emotion regulation during a  stressful situation during middle childhood. Frontal electroencephalogram (EEG)  asymmetries were measured during baseline and during a cognitive control task  at
4 years. Anxiety and emotion regulation were assessed during a stressful  situation at age 9 (speech task), along with measures of heart rate (HR) and  heart rate variability (HRV). Questionnaires were also used to assess anxiety  and emotion regulation at age 9. Results from this longitudinal study indicated  that children who exhibited right frontal asymmetry in early childhood  experienced more physiological arousal (increased HR, decreased HRV) during the  speech task at age 9 and less ability to regulate their emotions as reported by  their parents. Findings are discussed in light of the associations between  temperament and development of anxiety disorders.