Pupillometry in Developmental Psychology

Pupillometry holds tremendous potential for developmental psychology. The empirical evidence overwhelmingly suggests that psychologically mediated pupil dilation is a real phenomenon in human development. The general interest in studying systematic changes in pupil dilation in infants, young children, and beyond is anchored in such changes being a non-invasive, (neuro-)physiological variable, which - in addition to reflecting arousal state - indexes sudden surges in attention. Developmental psychology benefits from decades of adult and comparative research through which the mechanisms underlying pupil dilation are well-understood. This chapter provides an overview of how developmental pupillometry continues to emerge within three distinct areas of research: (1) surprise and violation of expectation paradigms, (2) task-evoked pupil dilation and neural activity, and (3) arousal state and motivation. The current heterogeneity in how pupil data are analysed and interpreted is evidence of developmental pupillometry, as a research discipline, being in a period of scientific growth as the method’s potential continues to be explored. Moving forward, pupillometry research across child development will look to further orchestrate and streamline processing pipelines to assert the extent to which the many psychological mechanisms identified to date are in fact evidence of broader psychological phenomena.