title: Smiling in newborns during communicative wake and active sleep.
abstract: Many studies have investigated infant smiling behaviour during wake and active sleep. In the majority of studies authors agreed that two month-old infants exhibit social smiles. However it is not clear if newborns exhibit different kinds of smiles during wake and active sleep to two month-old infants and if the communicative context can affect the quantity and quality of these smiles. The aim of this study was to test if different kinds of communication affects the amount and the quality of smiles during different behavioural states. Smiling behaviour was analyzed during interactive wake (IW) and active sleep (AS), in 40 newborns randomly assigned to 4 groups of 10 newborns each: continuous tactile communication group, discontinuous non periodic tactile communication group, discontinuous periodic tactile communication group, absent communication group. In the total sample the open/closed mouth (social/non social) smiles ratio was 38/5 during IW and 1/28 during AS (p < .001). Moreover these ratios were different between the four groups. Different kinds of tactile communication affect amount and quality of the smiles of newborns during IW and AS. Moreover the morphological difference of the smiles during IW and AS suggested that for newborns the smiling behaviour during IW could have a social meaning, as it does for two month-old infants.
authors.affiliation: Department of Dynamic and Clinical Psychology, University of Rome Sapienza, Rome, Italy.
authors.forename: Marco
authors.initials: M
authors.lastname: Cecchini
authors.forename: Eleonora
authors.initials: E
authors.lastname: Baroni
authors.forename: Cinzia
authors.initials: C
authors.lastname: Di Vito
authors.forename: Carlo
authors.initials: C
authors.lastname: Lai
mesh_terms: D003142:Communication; D005149:Facial Expression; D005260:Female; D006801:Humans; D018730:Infant Behavior / Q000502:physiology*; D007231:Infant, Newborn; D008297:Male; D012890:Sleep / Q000502:physiology*; D012904:Smiling / Q000502:physiology*