Categorical perception along the happy–angry and happy–sad continua in the first year of life

The current study investigated 6-, 9- and 12-month old infants' ability to categorically perceive facial emotional expressions depicting faces from two continua: happy-sad and happy-angry. In a between-subject design, infants were tested on their ability to discriminate faces that were between-category (across the category boundary) or within-category (within emotion category). Results suggest that 9- and 12 month-olds can discriminate between …