The Cat is Out of the Bag: Previous Experience and Online Comparison Jointly Influence Infant Categorization.

We examined the effect of 4-month-old infants previous experience with dogs and/or cats and their on-line comparison on their learning of the adult-defined category of cat in a visual familiarization task. In Experiment 1, 4-month-old infants (N=97) learning in the laboratory was jointly determined by whether or not they had experience with pets at home and their level of on-line comparison during familiarization. Specifically, only infants with pets at home who were also high comparers during familiarization remembered the individual cat exemplars or formed a summary representation of those cats. In Experiments 2 and 3, 4-month-old infants (N = 33) who were low comparers and/or did not have pets at home failed to discriminate among the individual items. These results are consistent with recent theorizing about the processes of how infants categorical representations are formed, and provide new understanding into how infants categorization unfolds over time.