We tested 6- and 8-month-old White and non-White infants (N = 53 total, 28 girls) from Northern California in a visual search task to determine whether a unique item in an otherwise homogeneous display (a singleton) attracts attention because it is a unique singleton and "pops out" in a categorical manner, or whether attention instead…

This study explores how 7-month-old infants categorize graphical images varying in basic perceptual features by using a fast periodic visual stimulation (FPVS) task. Most participants were Caucasian and their parents had a higher education, but the family's socioeconomic background was mixed. Experiment 1 (N = 23) tested brain responses to…

Accurate perception of emotional (facial) expressions is an essential social skill. It is currently debated whether emotion categorization in infancy emerges in a "broad-to-narrow" pattern and the degree to which language influences this process. We used an habituation paradigm to explore (a) whether 14- and 18-month-old infants perceive…

There is evidence that 4.5-month-olds do not always use surface pattern to individuate objects but that they can be primed to attend to pattern differences through select experiences. For example, if infants are first shown events in which the pattern of an object predicts its function (dotted containers pound and striped containers pour), they…

Two studies examined whether object names and functions act as cues to categories for infants. Findings indicated that both 14- and 18-month-olds were more likely to select the category match after being shown a novel category exemplar with its function than when given no additional cues. Only at 18 months did naming the objects enhance…

Vocalizations of infants were classified and analyzed in a longitudinal sample of infants ranging in age from 2 to 14 weeks. Results suggest that infants performed different types of vocalizations that can be interpreted as affective states from 2 weeks of age on. Parents responded with a highly diversified pattern of reactions to different infant…

Nine experiments examined 6- to 10-month-olds' formation of an abstract category representation for "between." Findings indicated that older, but not younger infants, could form an abstract category representation for "between" when performing in an object-variation version of the between categorization task. Six- to…

Describes connectionist model showing exclusivity asymmetries when categorizing visual stimuli, similar to pattern shown by infants. Examines asymmetries in terms of an associative learning mechanism, distributed internal representations, and statistics of feature distributions in the stimuli. Details test of model with infants, finding that…

Two experiments used object-manipulation tasks to examine whether one- to two-year-olds form superordinate-like categories by attending to object parts. Findings indicated that 14- and 18-month-olds behaved systematically toward categories with different, but not matching, parts. Without part differences, none formed superordinate categories.…

Two experiments examined 6-month olds' ability to categorize natural infant-directed utterances. Infants heard seven different tokens from one class of utterance (comforting, approving). Findings indicated that infants who later heard a test stimulus from the unfamiliar class showed response recovery, whereas those who heard a novel stimulus from…