The Development of Categorization

Project Summary The proposed project is designed to advance our understanding of the development of category learning – a fundamental component of human intelligence. The proposed research is based on the hypothesis of multiple mechanisms sub-serving category learning: (a) an early developing mechanism (Mechanism1) is based on distributed attention and learning of within-category statistics and (b) later developing mechanism (Mechanism2) is based on selective attention to category-relevant information. Under Mechanism1, both relevant and less relevant dimensions are encoded, with learned representations being similar to the input stimulus structure (i.e., no learning-based representational change). Under Mechanism2, learned representations are different from input stimulus structure (we refer to this difference as learning-based representational change). Differences between Mechanism1 and Mechanism2 will transpire in many performance indicators, including attention allocation during learning, memory for features, shapes of learning curves, and accuracy and response times during training and testing. To test these hypotheses, we will conduct a series of experiments with 4-9-year-old children, and adults. The proposed project has the following Specific Aims. Specific Aim 1 is to conduct cross-sectional experiments and a longitudinal study examining mechanisms of category learning across development. Mechanism1 and Mechanism2 predict qualitatively different patterns of (1) attention allocation, categorization, and memory and (2) pre- and post-learning representations of categories. Specific Aim 2 is to apply computational models to data collected within Study 1 to identify the differences between the two hypothesized mechanisms of category learning. To achieve this goal, eye gaze and categorization and memory choice and response time data will be submitted to a suite of models capturing the hypothesized mechanisms. The proposed project will advance our understanding of links among critical aspects of typical cognitive development – selective attention, category learning, and memory.