Proceedings of the Annual Meeting of the Cognitive Science Society

During the first year of life, infants develop a remarkable ability to group objects based on their similarities and differences. This ability of category formation represents one of the main mechanisms underlying the organisation of the semantic system. Early categories are formed spontaneously, in a non-supervised fashion and this type of category acquisition remains present even when more sophisticated forms of supervised category learning emerge. Even though there are various models of categorisation mechanisms across the lifespan, there is a gap in the research investigating implicit categorisation at different stages of cognitive development. Therefore, the aim of the current study was to compare processes of spontaneous concept formation in infants and adults using an experimental paradigm based on novelty preference. We discovered that both infants and adults show evidence of category learning (Experiment 1), though with different amount of training being needed to achieve the task. Adults successfully categorised objects already after a single block of training. Infants reached a level comparable to that of adults after twice the amount of training. As these tasks inevitably pose different cognitive and sensory demands to the two groups, in Experiments 2 and 3 we explored how varying parameters of the learning context affect dynamics of category formation. Decreasing memory demands of the task resulted in an acceleration of infants’ category formation (Experiment 2), whereas posing memory load in an implicit category learning task decelerated adults’ dynamics of category formation (Experiment 3).