Keynote Series: Lucia Melloni — Adversarial Collaboration : Large scale collaborations to help define and measure the neural correlates of consciousness

By Alexander Albury

What makes someone conscious? What is consciousness? Scientists and philosophers have been asking these questions for millennia. And the field of consciousness has made significant progress in the last century. But questions still remain and competing viewpoints have arisen to define what consciousness is and, more recently, how it presents itself in the brain. One group of researchers set out to rigorously test two competing theories of consciousness using a large-scale collaborative consortium spanning multiple labs and using several neuroimaging methodologies. The pre-registered, ongoing project stands as a prime example of open science and reproducibility.

Dr. Lucia Melloni, one of OHBM’s keynote speakers for the 2024 Annual Meeting, is one of the leaders of this massive project. On the surface, the goal was simple: design a protocol to test Global Neuronal Workspace Theory and Integrated Information Theory, two of the most prominent theories in modern consciousness research. These two theories have progressed independently of each other, and while both make claims about the neural correlates of consciousness, some of these claims are opposing. Dr. Melloni and collaborators set out to rigorously test both of these theories.

First, they chose key claims from both theories with an emphasis on those that were most contradictory to each other. They then employed two complementary experiments that were designed to confirm some of the theories’ predictions while challenging others. The protocols were tested in multiple samples using fMRI, MEG, and intracranial EEG for a total of 250 subjects across all modalities. However, these protocols will also be completed in duplicate in two independent laboratories, bringing the total number of participants to 500. The final data set will then be divided in half with equal amounts of data from each lab. 

After the data is collected, the researchers will then implement a phased analysis approach with an emphasis on replicability. In the first phase of analysis, one half of the data will be used to identify and design the best analysis techniques to test each of the theories claims. This will be done in collaboration with expert advisors in the fields of consciousness, neuroscience, and statistics, and the final analyses and results will be preregistered in a public repository. After this, the preregistered analyses will be conducted on the remaining half of the data as a built-in replication.

Although no research design and methodology can be perfect, this team’s commitment to open science and reproducibility serves as the gold standard of how we can tackle controversial scientific questions in an unbiased and rigorous way. With this project Dr. Melloni and her collaborators are on track to discover the neural correlates of consciousness and how we can quantify conscious experience.

Original Research:

Melloni, L., Mudrik, L., Pitts, M., Bendtz, K., Ferrante, O., Gorska, U., Hirschhorn, R., Khalaf, A., Kozma, C., Lepauvre, A., Liu, L., Mazumder, D., Richter, D., Zhou, H., Blumenfeld, H., Boly, M., Chalmers, D. J., Devore, S., Fallon, F., … Tononi, G. (2023). An adversarial collaboration protocol for testing contrasting predictions of global neuronal workspace and integrated information theory. PLOS ONE, 18(2), e0268577. https://doi.org/10.1371/journal.pone.0268577

If you’d like to learn more about Dr. Melloni’s research, check out our interview with her here.