By combining multimodal neuroimaging data, a framework was developed that demonstrates the fundamental principles of bidirectional coupling between neuronal and neurotransmitter dynamical systems. The work causally explains the functional effects of stimulating specific serotoninergic receptors (5-HT2AR) with psilocybin in healthy humans. This could lead to a better understanding of why psilocybin shows promise as a therapeutic intervention for neuropsychiatric disorders such as depression, anxiety, and addiction.
Access of sensory information to consciousness depends on neural activity crossing a threshold in the prefrontal cortex (PFC), yet how brain state fluctuations interact with conscious content is unclear. Using multielectrode recordings during a no-report binocular rivalry task in animals, two distinct prefrontal states were identified: low-frequency (1-9 Hz) bursts that precede spontaneous switches in conscious perception (perceptual update), and beta-band (20-40 Hz) bursts correlated with stable perception. Beta bursts synchronize neural ensembles coding the perceived stimulus. Similar fluctuations occur during rest, suggesting they are endogenous. The findings indicate that global cortical states, not selective spiking, drive internal switches in conscious perception.
The prefrontal cortex can represent the contents of conscious perception even when no overt report is required. Recordings from macaque monkeys during binocular rivalry—where perception alternates between two conflicting images—showed that neural ensemble activity in the prefrontal cortex decoded which image the animal was seeing as accurately as when images were presented without competition. This decoding remained significant even when eye movements were suppressed, indicating that the signals were not solely due to oculomotor confounds. The findings suggest that prefrontal population dynamics reflect internally driven changes in conscious perception during multistable vision.