Social and communicative not a prerequisite: Preverbal infants learn an abstract rule only from congruent audiovisual dynamic pitch-height patterns.

Learning in the everyday environment often requires the flexible integration of relevant multisensory information. Previous research has demonstrated preverbal infants' capacity to extract an abstract rule from audiovisual temporal sequences matched in temporal synchrony. Interestingly, this capacity was recently reported to be modulated by crossmodal correspondence beyond spatiotemporal matching (e.g., consistent facial emotional expressions or articulatory mouth movements matched with sound). To investigate whether such modulatory influence applies to non-social and non-communicative stimuli, we conducted a critical test using audiovisual stimuli free of social information: visually upward (and downward) moving objects paired with a congruent tone of ascending or incongruent (descending) pitch. East Asian infants (8-10 months old) from a metropolitan area in Asia demonstrated successful abstract rule learning in the congruent audiovisual condition and demonstrated weaker learning in the incongruent condition. This implies that preverbal infants use crossmodal dynamic pitch-height correspondence to integrate multisensory information before rule extraction. This result confirms that preverbal infants are ready to use non-social non-communicative information in serving cognitive functions such as rule extraction in a multisensory context.