Using a single feature to discriminate and form categories: the interaction between color, form and exemplar number

There is relatively little work that has focused on how infants use a single feature to discriminate objects or flexibly group objects together. Existing research suggests that the ease with which infants learn form and color discriminations is not equal. However, which of these dimensions is easier when discriminating between objects is still unclear. The studies in this paper tested how infants used these two dimensions under varying levels of diversity in a discrimination task. Combining traditional analyses with latent-states Markov-modeling, infant learning in these studies was characterized by a bend of overt behavior and attentional processes. Infants were able to learn both a color and form-based discrimination, but only generalized the form distinction to new stimuli. When presented with diversity on the irrelevant dimension, infants in the form condition learned quickly. However, infants in the color-condition did not show signs that they learned the distinction. The results show that infants could use both dimensions to distinguish between objects, but that form-based distinctions were easier and more likely to be generalized to new objects.