Locomotion-dependent auditory gating to the parietal cortex mediates flexible multisensory decisions

Decision-making in mammals is fundamentally based on the integration of several senses. When different sensory inputs guide conflicting outcomes, animals make decisions following the prepotent sensory modality. However, the neural basis of state-dependent flexibility in sensory dominance and multisensory decisions remains obscure. Here, we found that locomotion switched auditory-dominant decisions to visual-dominant ones in mice with audiovisual conflicts. When mice made auditory-dominant decisions, the visual representation in the posterior parietal cortex (PPC) was weakened. Prolonged locomotion restored visual representation in the PPC and induced visually dominant decisions by inhibiting the auditory cortical neurons projecting to the PPC (AC _PPC ). In contrast, it had no effect on the AC projection to the striatum, which mediated auditory decisions. Locomotion activated the AC-projecting secondary motor cortex neurons, which preferentially inhibited the AC _PPC neurons. Our findings demonstrate that animals make flexible multisensory decisions by gating auditory afferents to the association cortex depending on locomotor conditions.