Observer pro 5.0 system

Two independent coders who have not been involved in the design of the study, the data collection, and interpretation, coded the data. The three phases were coded frame-by-frame, using the Noldus Observer-Pro 5.0 system [19 ]. The behavioural variables coded in this study were identical to the variables coded in Nagy’s earlier experiment that found evidence for neonatal responsivity to the SFP [3 (link)]. We chose to code the same variables, thus the results of the two studies could be directly comparable. Infants’ gaze behaviour (looking at the experimenter) was coded as approach behaviour. Distress was coded using the codes of distressed face (distress on the face with or without vocalization and fussing but not crying), and crying (audible crying). Sucking the fingers, hands and mouth, and sleeping were coded as self-regulatory behaviours. Gaze and negative affective behaviours such as distress and crying are the most commonly coded variables in the SFP literature, therefore the results are also comparable to results with older infants [6 ]. While coding, the part of the screen showing the experimenter was covered for the coders, who were unaware of the experimenter’s behaviour. All behaviours were coded and analysed for both their frequencies and durations.