At the origins of emotions: a pilot study on the facial expression of distress and smiling in very low gestational age preterm newborns

The aim of the study was to test the presence of smiling and distress, two fundamental facial expressions in early infancy, in a group of very low gestational age preterm newborns. The facial behaviour of 9 healthy preterm newborns with an average weight of 945.6 grams (DS = 132) at birth, appropriate for gestational age (AGA), videorecorded at 30 post-conceptional weeks, was analyzed by using two coding systems, Baby FACS (Oster, in press) and MAX (Izard, 1979). The results showed that more than one-half of the sample presented both expressions bilaterally and at the higher muscular intensity level (b/x; Ekman & Friesen, 1978). The frequency of unilateral actions was higher during smiling than during distress, which was by contrast almost totally bilateral. Furthermore, mean duration of distress was significantly longer than smiling. The data suggest an early asynchrony between the emergence of smiling and distress expressions.