Parent-to-child transmission of information processing biases to threat is a potential causal mechanism in the family aggregation of anxiety symptoms and traits. This study is the first to... Show moreParent-to-child transmission of information processing biases to threat is a potential causal mechanism in the family aggregation of anxiety symptoms and traits. This study is the first to investigate the link between infants' and parents' attention bias to dynamic threat-relevant (versus happy) emotional expressions. Moreover, the associations between infant attention and anxiety dispositions in infants and parents were explored. Using a cross-sectional design, we tested 211 infants in three age groups: 5-to-7-month-olds (n = 71), 11-to-13-month-olds (n = 73), and 17-to-19-month-olds (n = 67), and 216 parents (153 mothers). Infant and parental dwell times to angry and fearful versus happy facial expressions were measured via eye-tracking. The parents also reported on their anxiety and stress. Ratings of infant temperamental fear and distress were averaged across both parents. Parents and infants tended to show an attention bias for fearful faces with marginally longer dwell times to fearful versus happy faces. Parents dwelled longer on angry versus happy faces, whereas infants showed an avoidant pattern with longer dwell times to happy versus angry expressions. There was a significant positive association between infant and parent attention to emotional expressions. Parental anxiety dispositions were not related to their own or their infant's attention bias. No significant link emerged between infants' temperament and attention bias. We conclude that an association between parental and infant attention may already be evident in the early years of life, whereas a link between anxiety dispositions and attention biases may not hold in community samples. Show less