Science annotation · annotations/sa-008

The brain's primary function is to restrict consciousness rather than produce it, filtering out most of what could be perceived.

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Partially Confirmed

The brain's primary function is to restrict consciousness rather than produce it, filtering out most of what could be perceived.

Claim source
The Doors of Perception, Chapter 1
Current evidence · confidence: high
The REBUS model (Carhart-Harris & Friston, Pharmacological Reviews, 2019) formalizes this: the brain generates top-down predictions (priors) that suppress most bottom-up sensory information. Default Mode Network activity, the brain's self-referential processing system, was reduced under psilocybin in early fMRI work (Carhart-Harris et al., PNAS, 2012), allowing more sensory information through. Linking Huxley's reducing valve to the default mode network is an interpretation; it is a useful model, not an established fact.
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Carhart-Harris & Friston (2019); Carhart-Harris et al., PNAS (2012)

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From Reducing Valve to REBUS: Huxley's Neuroscience, Seventy Years On, the editorial draft this item belongs with
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