Did the popsicle melt? Preschoolers' performance in an episodic-like memory task

Episodic memory has been tested in non-human animals using depletion paradigms that assess recollection for the "what", "where" and "when" (i.e., how long ago). This paradigm has not been used with human children, yet doing so would provide another means to explore their episodic memory development. Using a depletion paradigm, preschool-aged children were presented in two trials with a preferred food that was only edible after a short interval and a less-preferred food that was edible after the short and long intervals. Younger (mean = 40 months) and older (mean = 65 months) children tended to choose their preferred food after the short intervals, but did not switch to selecting their less-preferred food after the long intervals. Importantly, their choices did not differ with age. Although older children better remembered "what", "where", and "what is where" than did younger children, neither age group successfully estimated "how long ago" an event occurred. Finally, both age groups spontaneously recalled information about Trial 1. We also analysed the relation between the different measures used in the study but no clear patterns emerged. Results are discussed with respect to the cognitive mechanisms necessary to succeed in depletion paradigms and the measurement of episodic memory more broadly.