BOLD fMRI investigation of auditory and visual interactions in the inferior colliculus

Abstract

Multisensory interaction is crucial for forming an accurate representation of the environment and facilitating behavioral responses. Previous studies of multisensory interaction are focused on the cortex. The midbrain inferior colliculus (IC) is a pivotal station in the auditory pathway. Although evidence suggests that the IC receives non-auditory anatomical and signal input, it remains unclear how other sensory signals interact with auditory processing within the IC. Using BOLD fMRI, this study shows that a strong visual stimulation inhibits IC responses to following noise stimulation. Multisensory interaction therefore occurs much earlier before sensory signals reach the cortex.