Supervised Calibration Relies on the Multisensory Percept

Multisensory plasticity enables us to dynamically adapt sensory cues to one another and to the environment. Without external feedback, "unsupervised" multisensory calibration reduces cue conflict in a manner largely independent of cue reliability. But environmental feedback regarding cue accuracy ("supervised") also affects calibration. Here we measured the combined influence of cue accuracy and cue reliability on supervised multisensory calibration, using discrepant visual and vestibular motion stimuli. When the less reliable cue was inaccurate, it alone got calibrated. However, when the more reliable cue was inaccurate, cues were yoked and calibrated together in the same direction. Strikingly, the less reliable cue shifted away from external feedback, becoming less accurate. A computational model in which supervised and unsupervised calibration work in parallel, where the former only relies on the multisensory percept, but the latter can calibrate cues individually, accounts for the observed behavior. In combination, they could ultimately achieve the optimal solution of both external accuracy and internal consistency.