An active role of inferior frontal cortex in conscious experience.

Inferior frontal cortex plays a causal role in resolving perceptual ambiguities, thereby determining what is consciously experienced. Computational modeling and two fMRI experiments showed that this region detects conflicts caused by ambiguous sensory information. Disrupting inferior frontal cortex activity with transcranial magnetic stimulation slowed the updating of conscious experience in response to such conflicts. These findings indicate that prefrontal cortex is not merely involved in introspection or action but actively contributes to shaping the contents of consciousness.

Study at a glance

Abstract

In the search for the neural correlates of consciousness, it has remained controversial whether prefrontal cortex determines what is consciously experienced or, alternatively, serves only complementary functions, such as introspection or action. Here, we provide converging evidence from computational modeling and two functional magnetic resonance imaging experiments that indicated a key role of inferior frontal cortex in detecting perceptual conflicts caused by ambiguous sensory information. Crucially, the detection of perceptual conflicts by prefrontal cortex turned out to be critical in the process of transforming ambiguous sensory information into unambiguous conscious experiences: in a third experiment, disruption of neural activity in inferior frontal cortex through transcranial magnetic stimulation slowed down the updating of conscious experience that occurs in response to perceptual conflicts. These findings show that inferior frontal cortex actively contributes to the resolution of perceptual ambiguities. Prefrontal cortex is thus causally involved in determining the contents of conscious experience.