Divisively normalized integration of multisensory error information develops motor memories specific to vision and proprioception

ABSTRACT Both visual and proprioceptive information contribute to accurate limb movement, but the mechanism of integration of these different modality signals for movement control and learning remains controversial. Here, we aimed to elucidate the mechanism of integration by examining motor adaptation when various combinations of visual and proprioceptive perturbations were applied during reaching movements. We found that the movement corrections by adaptation were explained by a mechanism known as a divisive normalization, which was previously reported to be the mechanism underlying the integration of multisensory signals in neurons. Furthermore, we found evidence that the motor memory for each sensory modality was formed separately and the outputs from these memories were integrated. These results provide a novel view of the utilization of different sensory modality signals in motor control and adaptation.