A neural circuit for integration of visual-auditory conflicts in the mouse

Abstract

When simultaneous visual and auditory signals have spatial or temporal mismatch, animal resolves these conflicts via brain circuits for integration and elicits coherent responses. During the integration of conflicts, one perception often dominates the other. However, we still do not understand the neural mechanism of sensory integration of conflicts. Here, we devised the visual-auditory discrimination tasks both under the actual and artificial conditions. In head-fixed mice, audition dominated vision in perception of audiovisual conflicts, a process mediated by interaction between primary visual (V1) and primary auditory (A1) cortices in posterior parietal cortex (PTLp). Inactivation of PTLp by muscimol or optogenetic inhibition of PV+ interneurons switched the auditory dominance to visual dominance without affecting visual or auditory perception. Furthermore, only V1-selective neurons in PTLp showed significant reduction in their responses to simultaneous V1 and A1 stimulation. Thus, our data demonstrate that A1 input-specific feed-forward inhibition of V1 inputs in PTLp mediates the auditory-dominant perception during the integration of visual-auditory conflict.