The relationship between prior night's sleep and measures of infant imitation.

We examined whether sleep quality during the night and naps during the day preceding a learning event are related to memory encoding in human infants. Twenty-four 6- and twenty-four 12-month-old infants' natural sleeping behavior was monitored for 24 hr using actigraphy. After the recording period, encoding was assessed using an imitation paradigm. In an initial baseline phase, infants were allowed to interact with the stimulus to assess spontaneous production of any target actions. Infants then watched an experimenter demonstrate a sequence of three target actions and were immediately given the opportunity to reproduce the demonstrated target actions to assess memory encoding. Analyses revealed significant correlations between nighttime sleep quality variables (sleep efficiency, sleep fragmentation) and immediate imitation in 6-month-olds, but not in 12-month-olds. High sleep quality in the preceding night was thus positively associated with next day's memory encoding in 6-month-old infants. © 2016 Wiley Periodicals, Inc. Dev Psychobiol 9999: 1-12, 2016

Mother's face recognition in newborn infants: learning and memory

Two studies are reported that address issues related to memory for faces in young infants. The first correlates the opportunity to view the mother’s face with expressed visual preference for that face, and shows that very little exposure is required, with greater levels of exposure showing stronger preferences. The second study examines the role of delay between exposure to the mother’s face and preference testing, finding that strength of preference is not significantly impacted by a 15-min delay. Implications for a model of face processing are discussed