Audio recordings of mother-infant interactions were collected during a brief play session. Parents were asked to "play with their child as they normally would" using some age appropriate soft toys and anything in the room as though they were "at home".
Audio data were collected using a head set microphone, or microphone to record the vocalisations of the mother and infant for acoustic analysis. Acoustic variables include mean, maximum, minimum and range fundamental frequency (F0; hertz). Ratings were also given by undergraduate university students to indicate the level of “valence” and “arousal” in low-pass filtered excerpts of the mother's speech to her infant.
