Abstract
Previous work has suggested that active motor learning of unisensory items enhances memory while leading to the involvement of motor systems during subsequent perception and recognition. However, the impact of active motor learning on the subsequent perception and recognition of multisensory associations has not been investigated. This is important because we commonly learn through multiple senses while using physical interaction. Therefore, a behavioral and fMRI study was performed in order to explore the impact of active motor learning on subsequent processing of audiovisual stimuli. These stimuli were twenty novel visual objects, viewed from an egocentric viewpoint, that each produced a unique sound when a specific action was performed on the object. Participants learned audiovisual associations from these stimuli either through self-generated actions on the objects (active learning condition), or by observing an experimenter produce the actions (passive learning condition). Immediately after the learning session, accuracy, reaction time, and BOLD fMRI measures were collected during associative perception and recognition tasks. Actively and passively learned stimuli were presented in unisensory (visual and auditory), correctly paired multisensory (congruent audiovisual), and incorrectly paired multisensory (incongruent audiovisual) forms. Active learning facilitated behavioral measures of audiovisual associative recognition. Premotor, motor, and somatosensory cortex were recruited more during the presentation of actively learned audiovisual associations compared to the presentation of passively learned audiovisual associations. Importantly these differences were modulated by the congruency of the paired associations. Overall, the current study demonstrates that active motor learning modulates subsequent audiovisual associative perception and recognition.