Widespread, perception-related information in the human brain scales with levels of consciousness

The human brain generates coherent, subjective perceptions by distributing stimulus-specific information throughout the whole brain, not just in dedicated regions. Using fMRI, researchers found that information about a stimulus, such as a banana, is spread across the neocortex, subcortex, and cerebellum, even in voxels typically considered noise. These signals are influenced by sedation levels, linking them to perception rather than mere sensory encoding. The findings challenge the traditional view that perception arises from processing in isolated brain regions and suggest that widespread, stimulus-specific, and consciousness-dependent signals may underlie coherent subjective experiences.

Study at a glance

Abstract

Abstract How does the human brain generate coherent, subjective perceptions—transforming yellow and oblong visual sensory information into the perception of an edible banana? This is a hard problem. According to the standard viewpoint, processing in groups of dedicated regions—identified as active “blobs” when using functional magnetic resonance imaging (fMRI)—gives rise to perception. Here, we reveal a new organizational concept by discovering that stimulus-specific information distributed throughout the whole brain. Using fMRI, we found stimulus-specific information across the neocortex, even in voxels previously considered “noise,” challenging traditional analytical approaches. Surprisingly, these stimulus-specific signals were also present in the subcortex and cerebellum and could be detected from across-subject variances. Finally, we observed that stimulus-specific signal in brain regions beyond the primary and secondary sensory cortices is influenced by sedation levels, suggesting a connection to perception rather than sensory encoding. We hypothesize that these widespread, stimulus-specific, and consciousness level-dependent signals may underlie coherent and subjective perceptions.