Repeated but not incremental training enhances cross-modal recalibration

Sensory representations are constantly realigned. For instance, in the ventriloquism aftereffect, short exposure to audiovisual stimuli with a consistent spatial disparity results in an adjustment of auditory spatial representations. Here we tested whether repeated audiovisual training over several sessions enhances recalibration in the ventriloquism aftereffect. One group of participants (n = 16) received incremental training in which the presented degree of audiovisual spatial disparity increased over the course of 3 days, whereas a second group (n = 16) was constantly exposed to the largest disparity during all three sessions (constant training). Within each session, a significant ventriloquism aftereffect was observed in both groups. However, the size of the final ventriloquism aftereffect was larger in the constant group, due to an increase over days that was not evident in the incremental group. These findings replicated results obtained in two prestudies that either used a smaller sample size or included constant training only. Taken together, our findings provide strong evidence that recalibration effects are retained and consolidated between sessions, contrary to the intuitive assumption that natural audiovisual stimulation outside the laboratory would immediately overwrite recalibration. Repeated training seems to be particularly effective for consistent changes in cross-modal stimulation.