The entropic brain - revisited.
Neuropharmacology November 1, 2018 DOI: 10.1016/j.neuropharm.2018.03.010 via PubMed
Summary
AI-generated from the abstractThe entropic brain hypothesis proposes that the entropy of spontaneous brain activity, within certain limits, indexes the informational richness of conscious states. Four years after its original publication, evidence from separate studies increasingly supports the principle that brain entropy is elevated in the psychedelic state, and evidence for greater brain criticality under psychedelics is also highlighted. Heightened brain criticality may make the brain more sensitive to intrinsic and extrinsic perturbations, translating as a heightened susceptibility to 'set' and 'setting'. This updated hypothesis offers more concrete information on specific measures of brain entropy and suggests new studies to scrutinize its utility for conditions such as depression and disorders of consciousness.
Study at a glance
| Characteristics | Review Peer reviewed |
|---|---|
| Topics | Depression Serotonin |
| Keywords | 5-ht2a Criticality Entropy Psychedelics |
| Key finding | Evidence increasingly supports that brain entropy is elevated in the psychedelic state and that brain criticality is heightened under psychedelics, potentially increasing sensitivity to set and setting. |
Abstract
The entropic brain hypothesis proposes that within upper and lower limits, after which consciousness may be lost, the entropy of spontaneous brain activity indexes the informational richness of conscious states. Here the hypothesis is revisited four years on from its original publication. It is shown that the principle that the entropy of brain activity is elevated in the psychedelic state is increasingly well supported by separate and independent studies and analyses, and evidence for greater brain criticality under psychedelics is also highlighted. It is argued that heightened brain criticality enables the brain to be more sensitive to intrinsic and extrinsic perturbations which may translate as a heightened susceptibility to "set" and "setting". This updated version of the original entropic brain hypothesis now offers more concrete information on specific measures of brain entropy and suggests new studies to scrutinise it further, as well as examine its utility for describing and informing the treatment of psychiatric and neurological conditions such as depression and disorders of consciousness. This article is part of the Special Issue entitled 'Psychedelics: New Doors, Altered Perceptions'.