Beyond Vision: Response of the Mouse Visual Cortex to Multimodal Stimulation.

Sensory perception emerges from the integration of multiple inputs from different sensory modalities, a process previously attributed to higher-order cortices. However, increasing evidence suggests that the primary visual cortex also processes nonvisual stimuli. Here, we investigated the response of the primary visual cortex to visual, auditory and somatosensory stimuli in awake, head-fixed mice using evoked local field potentials, multi- and single-unit recordings. Our results demonstrate that the primary visual cortex responds to auditory and somatosensory inputs with distinct frequency band modulations and firing rate patterns across monocular and binocular regions. Notably, somatosensory stimuli elicited the fastest response latencies, suggesting a privileged role in murine sensory processing. Auditory and somatosensory stimuli modulated the primary visual cortex activity similarly to contralateral visual inputs, whereas ipsilateral visual stimulation resulted in weaker responses. These findings indicate that the primary visual cortex is not solely dedicated to vision but also responds to auditory and somatosensory stimuli, supporting a potential role in multisensory processing.