Simultaneous Encoding Facilitates Multisensory Category Learning

Categories in the real world are often comprised of information from multiples senses, yet most studies of category learning focus on a single modality. It is imperative to study multisensory category learning not only to capture processes involved in naturalistic learning, but also because multisensory information may impact the underlying mechanisms supporting learning. In the current study, we examined how learning of audiovisual categories is impacted by presenting the same information simultaneously across modalities or separately within the same trial. Overall, simultaneous presentation led to better generalization performance across all trial types including when information was only presented in one modality or when audiovisual information was presented separately. Simultaneous presentation also encouraged learners to attend more to the auditory modality. These findings suggest that simultaneous presentation of category information across different modalities can facilitate learning relative to separate presentation of the same information. These results challenge current theoretical approaches to category learning that specifically focus on learning in single modalities. More broadly, these results demonstrate the necessity of investigating multisensory learning to reveal mechanisms supporting learning in more naturalistic multisensory contexts.