Everyday Parameters for Episode-to-Episode Dynamics in the Daily Music of Infancy

Abstract

Experience-dependent change pervades early human development. Though trajectories of developmental change have been well charted in many domains, the episode-to-episode schedules of experiences on which they are hypothesized to depend have not. Here, we took up this issue in a domain known to be governed in part by early experiences: music. Using a corpus of longform audio recordings, we parameterized the daily schedules of music encountered by 35 infants ages 6-12 months. We discovered that everyday music episodes, as well as the interstices between episodes, typically persisted less than a minute, with most daily schedules also including some very extended episodes and interstices. We also discovered that infants encountered music episodes in a bursty rhythm, rather than a periodic or random rhythm, over the day. These findings join a suite of recent discoveries from everyday vision, motor, and language that expand our imaginations beyond artificial learning schedules and enable theorists to model the history-dependence of developmental process in ways that respect everyday sensory histories. Future theories about how infants build knowledge across multiple episodes can now be parameterized using these insights from infants' everyday lives.

Keywords: Burstiness; Dynamics; Input; LENA; Music; Spacing.

Fig. 1

One day‐in‐the‐life of an infant encountering music episodes. Three thousand nine hundred and forty‐one musical seconds distributed across 164 episodes. (a) Histogram of this day's episode (purple) and interstice (green) durations, which are mostly brief together with some extended durations of each. (b) Music episodes and interstices distributed in an overall clustered daily temporal schedule.

Fig. 2

Durations of everyday music episodes and interstices between music episodes. Histograms of the durations of all (a) music episodes (N = 4798) and (b) interstices between music episodes (N = 4763) in the corpus. Dashed lines are each distribution's median duration.

Fig. 3

Bursty rhythms of music episodes over a day. (a) Histogram of the burstiness parameter from each recording in this corpus (N = 35). Dashed line depicts median burstiness. (b) Three illustrative daily schedules (top: B = 0.67, middle: B = 0.63, bottom: B = 0.59; episodes in purple and interstices in green).