Where does consciousness come from? Two rival theories face scientific scrutiny

Where Does Consciousness Come From? Two Theories Face Off in Landmark Neuroscience Study

A high-stakes experiment tests rival ideas about the origins of consciousness—and the results may redefine the field

The nature and origin of consciousness has long puzzled scientists and philosophers alike. Despite decades of inquiry, neuroscience still lacks a definitive explanation for how conscious awareness arises in the brain. Now, a massive, multi-lab experiment has pitted the two most influential theories of consciousness against each other, yielding results that could shift the scientific consensus on one of humanity’s oldest questions.

Published this week in Nature, the study from the Cogitate Consortium compared the predictions of Integrated Information Theory (IIT) and Global Neuronal Workspace Theory (GNWT), two fundamentally different frameworks for understanding conscious experience. Yet instead of crowning a victor, the research revealed significant challenges for both.

The two leading theories of consciousness

Integrated Information Theory, developed in part by Christof Koch of the Allen Institute, starts with an abstract definition of consciousness and asks what kinds of physical systems could give rise to it. It proposes that consciousness corresponds to the degree of "integrated information" processed within a system—essentially, the richer and more interconnected the information flow, the more conscious the system may be.

Global Neuronal Workspace Theory, on the other hand, is rooted in cognitive neuroscience. It suggests that consciousness functions like a mental stage where information becomes "spotlighted" when it’s globally broadcast across the brain. According to GNWT, this ignition is driven by activity in the brain’s frontal regions, such as the prefrontal cortex.

Though based on different foundations, both theories offer testable hypotheses—something rare in consciousness research, which often struggles with the challenge of studying subjective experience through objective methods.

Testing theories in the lab

To assess their claims, the Cogitate Consortium enlisted 12 theory-neutral laboratories and recruited 256 participants—an unusually large sample for neuroscience. Researchers used three types of brain-imaging techniques while subjects engaged in visual recognition tasks designed to involve conscious awareness.

The predictions diverged: GNWT anticipated neural "ignition" in the prefrontal cortex when subjects became aware of a stimulus. IIT predicted a sustained synchronization of neural activity in posterior regions of the brain. But neither theory’s predictions were conclusively supported.

“The fact that you didn’t see that [GNWT ignition] is something that I think is a significant challenge,” said Anil Seth, a neuroscientist at the University of Sussex who was not involved in the study.

Likewise, IIT’s expected synchrony in the brain’s rear regions failed to materialize clearly, raising questions about the accuracy of both models.

A scientific draw—but not a dead end

The outcome has stirred debate across the neuroscience community. Koch, who co-authored the study, and David Chalmers, a philosopher of mind, had a 25-year wager that neuroscience would crack the consciousness puzzle by 2023. Koch conceded the bet at a conference last summer, acknowledging the complexity of the problem.

Shortly after, a group of more than 100 scientists and philosophers signed an open letter labeling IIT "pseudoscience," arguing that its core claims are not falsifiable with current methods. The controversy, however, did not arise directly from the Cogitate study, according to Seth, but rather from broader concerns over methodological rigor in consciousness science.

Despite the inconclusive results, researchers say the study represents a crucial step forward. By requiring rival theories to generate precise, testable predictions in a shared experimental framework, the field may finally begin to converge on answers.

“It’s not about proving or disproving a single theory,” said Seth. “It’s about shifting the community’s collective understanding.”

A new model for neuroscience collaboration

The Cogitate study is a high-profile example of adversarial collaboration, a method that pits competing scientific ideas against each other under neutral conditions. The goal is not to “win” but to refine or discard theories based on empirical evidence.

Such collaborations mirror historical moments in science—most famously, the 1919 eclipse that tested and ultimately confirmed Einstein’s theory of general relativity over Newton’s model of gravity.

More studies of this kind are underway. Seth himself is involved in another adversarial collaboration that compares IIT with two other consciousness theories, aiming to clarify which aspects of brain activity are essential for subjective experience.

Why this matters beyond theory

Understanding consciousness has implications that extend far beyond academic debate. From assessing awareness in coma patients to refining anesthesia protocols, the stakes are real and immediate.

“There are people that are taken off life support because they’re assumed to be unconscious,” said Robert Chis-Ciure, a consciousness researcher at the University of Sussex. “The stakes are too high to not tackle the problem head-on.”

Even without a unified theory, neuroscience is already applying insights from this research to clinical and ethical challenges involving human awareness.

While the Cogitate study may not have delivered a definitive answer, it has laid the groundwork for a new, more rigorous era of consciousness research. In the coming years, theory-neutral experimentation and collaborative studies may provide the clarity that abstract models alone have failed to offer.

Stay tuned to The Horizons Times as the science of consciousness continues to evolve