Qu’est-ce que la conscience, et quels sont ses mécanismes cérébraux ? (6) - S. Dehaene (2025-2026)

This lecture is a masterclass in cognitive neuroscience, delivered by one of the field’s leading experts. Dehaene’s presentation is rigorous, well-structured, and grounded in cutting-edge research. He systematically builds on his global neuronal workspace theory, providing clear predictions and then testing them with elegant experiments. The use of non-human primate models with advanced recording techniques (two-photon microscopy, electrophysiology) allows for detailed neural analysis that is not possible in humans. The findings from Liping Wang’s lab on orthogonal subspaces in the prefrontal cortex are presented with clarity, and the new experiment on subliminal stimuli directly addresses the question of whether unconscious information can enter working memory. The results are compelling: while unconscious stimuli can evoke a brief, transient response, they do not lead to sustained activity or flexible routing, supporting the idea that consciousness is necessary for flexible working memory. Dehaene also discusses clinical applications, such as coma and disorders of consciousness, highlighting the potential for these findings to inform diagnosis and treatment. The lecture is well-paced, with clear visuals and explanations. The only minor critique is that some sections may be dense for a non-specialist audience, but this is a university lecture, not a popular science talk. Overall, this is an excellent, authoritative presentation of the current state of research on consciousness and working memory.

The title accurately reflects the content, which focuses on consciousness and its brain mechanisms, specifically the relationship with working memory.

9/10

Lecture by a leading cognitive neuroscientist at Collège de France, based on peer-reviewed research, with rigorous methodology and clear presentation.

Markers derived by PSI from the transcript: the creator did not define chapters.

• 02:00Introduction to the lecture and definition of working memory.
• 05:00Predictions from the global neuronal workspace theory.
• 10:00Discussion of Liping Wang's work on neural coding in prefrontal cortex.
• 20:00Description of the new experiment on subliminal stimuli and working memory.
• 30:00Results showing that unconscious stimuli do not enter working memory.
• 40:00Clinical applications for disorders of consciousness.
• 50:00Summary and conclusions.

• Collège de France - Course page — Official course page for the lecture series.
• Stanislas Dehaene's chair page — Information about the professor's chair.
• YouTube playlist of the course — Playlist containing all lectures of the course.

• Collège de France — Institution hosting the lecture.

• www.fondation-cdf.fr
• fr.linkedin.com
• www.threads.net