9-MONTH-OLD INFANTS LEARN ABOUT A PHYSICAL EVENT IN A SINGLE SESSION - IMPLICATIONS FOR INFANTS UNDERSTANDING OF PHYSICAL PHENOMENA

Infants' ability to learn about physical phenomena after only brief tr aining was observed. During training, infants first observed and handl ed a weighted ball or an identical-looking empty ball, then watched an experimenter place a ball in the bottom of a tube connected to a padd le. When infants pressed the paddle, the empty ball ascended the tube while the weighted ball stayed down. During test trials infants experi enced trials that were consistent and inconsistent (i.e., heavy ball a scended and empty ball did not) with training trials. Infants pressed and looked longer at the inconsistent events. A second experiment repl icated the findings and ensured that infants were not using prior know ledge about gravity and weight. Infants formed a representation of wha t was inside the balls, remembered what each ball did during training, and detected a violation of expectations about the ball's movement.