Relation of Infants' Memory and Expectation Formation: Evidence from Anticipatory Eye Movements and Pupil Diameter Changes

Theories have suggested that infants’ ability to form expectations and exhibiting anticipatory eye movements, highlight our memory’s function of providing a foundation upon which expectations for future events are formed. This study aimed to assess this hypothesis by investigating the relation between long-term memory and expectation formation in 3-month-old infants. Infants underwent the Visual Expectation Paradigm and after a delay of 24 hours, infants were tested with either a change in the stimuli or the same stimuli. Infants’ level of anticipatory eye movements were measured on both test days. This study also aimed to study the relation between working memory and long-term memory by investigating if temporal decay (a limitation of working memory), would affect infants’ long-term memory. To this end, this study assessed the effect of two different interstimulus intervals (ISIs) on infants’ long-term memory performance. Finally, changes in pupil diameter during encoding and retrieval were also measured.