Modifying infants’ sensitivity to audiovisual temporal mismatch

Abstract

Studies in adults reveal that a short-term exposure to asynchronous audiovisual signals induces temporal realignment between these signals (Di Luca et al., 2009; Fujisaki et al., 2004; Navarra et al., 2009; Vroomen et al., 2004). In contrast with this evidence in adults, Lewkowicz (2010) observed that infants increased their sensitivity to AV asynchrony after exposure to asynchronous AV speech. We investigated whether brief experience with an asynchronous AV event would increase infants’ ability to discriminate AV synchrony from asynchrony in non-speech stimuli or else induce temporal realignment as observed in adults. Twenty-four 6-month-old infants were tested in two phases (Test 1 and 2) using an intersensory paired-preference procedure, with simple stimuli (two balls bouncing against the floor — one ball bouncing in synchrony while the other one in asynchrony with respect to the bouncing sound). Between Test 1 and 2, infants were exposed to AV asynchrony (a presentation of an audiovisually asynchronous bouncing ball). The results revealed that infants detected the difference between AV synchrony and asynchrony only after being exposed to an asynchronous AV event. Our findings support the idea that experience with AV asynchrony has different consequences for adults and infants: while temporal AV recalibration is observed in adults, an increase of the sensitivity to AV asynchrony is observed in infants.