A recent study has rigorously tested two prominent neuroscience theories of consciousness: Integrated Information Theory (IIT) and Global Neuronal Workspace Theory (GNWT). The research employed intracranial EEG (iEEG), magnetoencephalography (MEG), and functional magnetic resonance imaging (fMRI) to overcome the limitations of individual measurement techniques.
The study challenged IIT's prediction regarding sustained synchronization in the posterior cortex, finding no long-lasting synchrony in these regions. This discovery casts doubt on IIT's neural basis of consciousness.
GNWT also faced challenges, with the absence of "ignition" at stimulus offset. The global workspace model anticipates widespread neuronal activity updating with changes in conscious content. However, robust offset responses were not observed in the prefrontal cortex. The research questions GNWT's assertion that the prefrontal cortex broadcasts the complete content of conscious experience, suggesting it may only transmit abstract information.
The study utilized preregistered hypotheses and protocols to minimize bias, focusing on the contents of consciousness, such as category and orientation. Researchers advocate for computational models to balance prediction centrality and measurement noise, promoting openness and transparency in consciousness research.