In 2022, British neuroscientist Anil Seth and I compiled a review that included 22 theories grounded in brain biology. Fast forward to 2024, and US public intellectual Robert Kuhn has identified over 200 theories, each proposing different insights about this enigmatic subject.
This backdrop sets the stage for Nature’s recent publication detailing the findings from an “adversarial collaboration” involving the Cogitate Consortium. Their focus was on two leading theories: global neuronal workspace theory and integrated information theory.
With numerous theories out there—some converge, some diverge—testing them has proved quite challenging. Discussions, or, frankly, debates among theorists have often been heated. At one point in 2023, following the announcement of the Cogitate findings, many experts signed an open letter declaring that integrated information theory was not only incorrect but lacked scientific validity.
Nonetheless, both global neuronal workspace theory and integrated information theory are among the most influential theories currently influencing consciousness discourse, alongside higher-order representation theories and local re-entry theory. Summarizing these theories isn’t easy, but each connects consciousness to the activity of neurons in distinct brain regions.
Proponents of these theories, along with some independent theorists, formulated predictions regarding the types of brain activity linked to consciousness. For instance, integrated information theory suggests that conscious perception should correspond to ongoing synchronization and activity in the posterior cortex, while global neuronal workspace theory posits that “neural ignition” should be observable at the onset and conclusion of a stimulus. Basically, one can supposedly deduce what a person is conscious of by analyzing their prefrontal cortex activity.
The posterior cortex consists of parts like the parietal, temporal, and occipital lobes, while the prefrontal cortex is at the front of the frontal lobe. The hypotheses put forth by this collaboration were examined by various unbiased teams worldwide.
Ultimately, the results were inconclusive. Some findings appeared to align with predictions from one theory or the other, yet others posed significant challenges. For example, the anticipated synchronization in the posterior cortex, as proposed by integrated information theory, was not observed. Conversely, the global neuronal workspace theory faced scrutiny since not all conscious contents could be decoded from the prefrontal cortex, and there was no detectable neural ignition upon stimulus presentation.
Even though this study didn’t seem to favor either theory, it marked a significant advancement for scientific inquiry. It demonstrates a new, more rigorous approach to theory testing in the consciousness community.
Often, researchers lean toward supporting their own theories rather than critically assessing them. However, a pivotal 2022 paper by members of the Cogitate Consortium revealed how the design of a study could predict which theory it backed. This highlights a tendency to focus on confirming rather than questioning established theories.
A noteworthy accomplishment of this collaboration was getting competing theorists to agree on specific, testable predictions—quite a feat, considering the abstract nature of both theories. Additionally, they managed to conduct experiments across various labs, which presented its own set of challenges given the differing commitments to each theory.
During the project’s early phases, the team sought guidance from psychologist Daniel Kahneman, a proponent of adversarial collaboration in research. He cautioned that one shouldn’t expect results to alter anyone’s allegiance to their theories, even if they favor one over another. Scientists, understandably, are often devoted to their ideas and may resist changing perspectives, even against contradictory evidence.
Now, this kind of stubbornness might appear counterproductive, but in the right context, it could spur scientific progress. Since the ideal approach to understanding consciousness is still unclear, the scientific community should tackle the issue from multiple angles. There’s a need for self-correction within the research field, yet it can be beneficial for scientists to remain true to their theoretical frameworks, even when faced with challenging outcomes.
Consciousness is a particularly complex issue. It’s uncertain whether the current methodologies are enough to unravel it, or if we need entirely new conceptual frameworks. What’s evident, however, is that if we aim to decipher the intricacies of subjective experience, embracing collaborative research models will be crucial.
