A Global-to-Basic Trend in Early Categorization: Evidence From a Dual-Category Habituation Task.

A series of 3 experiments are reviewed in which infants between 4 and 10 months of age were familiarized with members of 2 basic-level object categories. The degree of distinctiveness between categories was varied. Preference tests were intended to determine whether infants formed a single category representation (at a more global level) or 2 basic-level representations. Across 3 experiments, 10-month-old infants appeared to have formed multiple basic-level categories, whereas younger infants tended to form broader, more inclusive representations. The tendency to form multiple categories was influenced to some extent by category distinctiveness. Whereas 10-month-olds formed separate categories for all contrasts, 7-month-olds did so only when the 2 familiarized categories were from separate global domains. A perceptual account of the global-to-basic shift in early categorization is offered. Task dependencies in early categorization are also discussed.