Infants Are Superior In Implicit Crossmodal Learning And Use Other Learning Mechanisms Than Adults
While adults have to continuously adapt their internal representations of the sensory world, infants need to first acquire these models. We used event-related potentials to test the hypothesis that infants extract crossmodal statistics implicitly while adults learn them when task relevant. Six-month-old infants and adults were passively exposed to frequent standard audio-visual combinations (A1V1, A2V2, p=0.35 each), rare recombinations of the standard stimuli (A1V2, A2V1, p=0.10 each), and a rare deviant audio-visual combination with an infrequent auditory and visual element (A3V3, p=0.10). While both infants and adults differentiated between rare deviants and standards at early processing stages, only infants discriminated standards from recombined stimuli at a later processing stage. A second experiment revealed that adults discriminated recombined from standard combinations only when crossmodal combinations were task relevant. These results demonstrate a heightened sensitivity for crossmodal statistics in infants and a change in learning mode from infancy to adulthood.