Ferrante, O., et al,. (2025).
Nature.
Abstract
Different theories explain how subjective experience arises from brain activity. These theories have independently accrued evidence, but have not been directly compared. Here we present an open science adversarial collaboration directly juxtaposing integrated information theory (IIT) and global neuronal workspace theory (GNWT) via a theory-neutral consortium. The theory proponents and the consortium developed and preregistered the experimental design, divergent predictions, expected outcomes and interpretation thereof. Human participants (n = 256) viewed suprathreshold stimuli for variable durations while neural activity was measured with functional magnetic resonance imaging, magnetoencephalography and intracranial electroencephalography. We found information about conscious content in visual, ventrotemporal and inferior frontal cortex, with sustained responses in occipital and lateral temporal cortex reflecting stimulus duration, and content-specific synchronization between frontal and early visual areas. These results align with some predictions of IIT and GNWT, while substantially challenging key tenets of both theories. For IIT, a lack of sustained synchronization within the posterior cortex contradicts the claim that network connectivity specifies consciousness. GNWT is challenged by the general lack of ignition at stimulus offset and limited representation of certain conscious dimensions in the prefrontal cortex. These challenges extend to other theories of consciousness that share some of the predictions tested here. Beyond challenging the theories, we present an alternative approach to advance cognitive neuroscience through principled, theory-driven, collaborative research and highlight the need for a quantitative framework for systematic theory testing and building.
Here are some thoughts:
This research explores a major collaborative effort to empirically test two leading theories of consciousness: Global Neuronal Workspace Theory (GNWT) and Integrated Information Theory (IIT). These theories represent two of the most prominent perspectives among the more than 200 ideas currently proposed to explain how subjective experience arises from brain activity. GNWT suggests that consciousness occurs when information is globally broadcast across the brain, particularly involving the prefrontal cortex. In contrast, IIT posits that consciousness corresponds to the integration of information in the brain, especially within the posterior cortex.
To evaluate these theories, the Cogitate Consortium organized an “adversarial collaboration,” in which proponents of both theories, along with neutral researchers, agreed on specific, testable predictions derived from each model. IIT predicted that conscious experience should involve sustained synchronization of activity in the posterior cortex, while GNWT predicted that consciousness would involve a “neural ignition” process and that conscious content could be decoded from the prefrontal cortex. These hypotheses were tested across several labs using consistent experimental protocols.
The findings, however, were inconclusive. The data did not reveal the sustained posterior synchronization expected by IIT, nor did it consistently support GNWT’s predictions about prefrontal cortex activity and neural ignition. Although the results presented challenges for both theories, they did not decisively support or refute either one. Importantly, the study marked a significant step forward in the scientific investigation of consciousness. It demonstrated the value of collaborative, theory-neutral research and addressed a long-standing problem in consciousness science—namely, that most studies have been conducted by proponents of specific theories, often resulting in confirmation bias.
The project was also shaped by insights from psychologist Daniel Kahneman, who pioneered the idea of adversarial collaboration. He noted that scientists are rarely persuaded to abandon their theories even in the face of counter-evidence. While this kind of theoretical stubbornness might seem like a flaw, the article argues it can be productive when managed within a collaborative and self-correcting scientific culture. Ultimately, the study underscores how difficult it is to unravel the nature of consciousness and suggests that progress may require both improved experimental methods and potentially a conceptual revolution. Still, by embracing open collaboration, the scientific community has taken a crucial step toward better understanding one of the most complex problems in science.
