Understanding the effects of one's actions upon hidden objects and the development of search behaviour in 7-month-old infants

Pupillometric VoE paradigm reveals that 18- but not 10-month-olds spontaneously represent occluded objects (but not empty sets)

Object permanence has been investigated with a variety of paradigms and measures, yielding heterogeneous findings. The current study employed a novel Violation-of-Expectation paradigm measuring pupil dilation as indicator of cognitive effort and surprise. Across repeated trials, infants watched videos of animated toys either stopping in an open door frame or moving across the open door frame off screen. The door then closed and opened up again to reveal either the toy, or an empty space. In Experiment 1, 18-month-olds's pupils dilated in response to the unexpected empty outcome more than to the expected empty outcome, establishing the paradigm as a suitable measure of violation of object expectation. Using the same paradigm, Experiment 2 revealed an absence of this object expectation effect for 10-month-olds. Results are discussed with regard to paradigmatic aspects and developmental differences. It is suggested that young infants do not automatically represent occluded objects upon perceiving occlusion events, and that occlusion events may initially require relevance in terms of individual activity or social interaction.

Means-end problem solving in infancy: Development, emergence of intentionality, and transfer of knowledge

Behaviors and performance of 23 typically developing infants were assessed longitudinally at 6, 9, 12, 18, and 24 months in two means-end tasks: pulling a towel or rotating a turntable to obtain a supported object. With age, infants performed more goal-directed behaviors, leading to increased problem-solving success. Intentionality emerged earlier in the towel task than in the turntable task (6.9 vs. 10.8 months). Potential knowledge transfer between the tasks was first observed at 9 months. This study provides insight into the development of means-end learning, the emergence of intentionality, and potential transfer of knowledge in tasks involving a similar concept (support) but requiring different modes of action for success (pulling vs. rotating).

Prematurity may negatively impact means-end problem solving across the first two years of life

Preterm infants are at risk for delays in motor, perceptual, and cognitive development. While research has shown preterm infants may exhibit learning delays in the first months of life, these delays are commonly under-diagnosed. The purpose of this study was to longitudinally evaluate behavioral performance and learning in two means-end problem-solving tasks for 30 infants born preterm (PT) and 23 born full-term (FT). Infants were assessed at 6, 9, 12, 18, and 24 months-old in tasks that required towel pulling or turntable rotation to obtain a distant object. PT infants performed more non-goal-directed and less goal-directed behavior than FT infants throughout the study, resulting in a lower success rate among PT infants. PT infants showed delayed emergence of intentionality (prevalence of goal-directed behaviors) compared to FT infants in both tasks. Amount and variability of behavioral performance significantly correlated with task success differentially across age. The learning differences documented between PT and FT infants suggest means-end problem-solving tasks may be useful for the early detection of learning delays. The identification of behaviors associated with learning and success across age may be used to guide interventions aimed at advancing early learning for infants at risk.