"In that famous example of the dress, half of the people in the world saw [blue and black], half saw [white and gold]. It turns out there’s individual differences in how brains take into account ambient light. Colour is one example where it’s pretty clear that what we experience is a kind of inference: it’s the brain’s best guess about what’s going on in some way out there in the world. And that’s the claim that I’ve taken on board as a general hypothesis for consciousness: that all our perceptual experiences are inferences about something we don’t and cannot have direct access to." —Anil Seth

In today’s episode, host Luisa Rodriguez speaks to Anil Seth — director of the Sussex Centre for Consciousness Science — about how much we can learn about consciousness by studying the brain.

Links to learn more, highlights, and full transcript.

They cover:

What groundbreaking studies with split-brain patients and blindsight have already taught us about the nature of consciousness.
Anil’s theory that our perception is a “controlled hallucination” generated by our predictive brains.
Whether looking for the parts of the brain that correlate with consciousness is the right way to learn about what consciousness is.
Whether our theories of human consciousness can be applied to nonhuman animals.
Anil’s thoughts on whether machines could ever be conscious.
Disagreements and open questions in the field of consciousness studies, and what areas Anil is most excited to explore next.
And much more.

Chapters:

Cold open (00:00:00)
Luisa’s intro (00:01:02)
The interview begins (00:02:42)
How expectations and perception affect consciousness (00:03:05)
How the brain makes sense of the body it’s within (00:21:33)
Psychedelics and predictive processing (00:32:06)
Blindsight and visual consciousness (00:36:45)
Split-brain patients (00:54:56)
Overflow experiments (01:05:28)
How much can we learn about consciousness from empirical research? (01:14:23)
Which parts of the brain are responsible for conscious experiences? (01:27:37)
Current state and disagreements in the study of consciousness (01:38:36)
Digital consciousness (01:55:55)
Consciousness in nonhuman animals (02:18:11)
What’s next for Anil (02:30:18)
Luisa’s outro (02:32:46)

Producer: Keiran Harris
Audio engineering: Ben Cordell, Milo McGuire, Simon Monsour, and Dominic Armstrong
Content editing: Luisa Rodriguez, Katy Moore, and Keiran Harris
Transcriptions: Katy Moore

#206 – Anil Seth on the predictive brain and how to study consciousness

80,000 Hours Podcast