High-resolution 7T fMRI reveals the visual sensory zone of the human claustrum

The claustrum is a thin subcortical gray matter structure located between the insula and the putamen. It has numerous bilateral connections with the cortex and is thought to play an important role in higher-level aspects of perception and cognition, with hypotheses including multisensory integration, attention and consciousness. The claustrums thin shape makes it difficult to investigate, leaving the hypothesis regarding its function largely untested. In the current study, we used high-resolution ultra-high field (7 Tesla) functional magnetic resonance imaging (fMRI) to measure claustrum activity in human participants, while they were presented with visual, auditory or audiovisual naturalistic stimuli. We found distinct visual responses in the claustrum at a spatial location that was consistent across participants, hemispheres and scanning sessions. This is the first study to demonstrate evoked sensory responses within the human claustrum. It opens the possibility for future noninvasive investigation of the claustrums role in sensory processing.