Commentary: The entropic brain: a theory of conscious states informed by neuroimaging research with psychedelic drugs

The entropic brain hypothesis proposes that conscious states are linked to the brain's entropy, with psychedelic states exemplifying primary states where brain activity becomes more random and harder to predict than in normal wakeful consciousness. This suggests psychedelic-induced brain activity exhibits criticality, while normal wakefulness is subcritical. However, the text questions whether entropy can uniquely indicate the quality of consciousness and raises doubts about whether psychedelic-induced activity is truly critical.

Study at a glance

Abstract

The “entropic brain hypothesis” holds that the quality of conscious states depends on the system’s \nentropy (Carhart-Harris et al., 2014). Brain activity is said to become “more random and so harder \nto predict in primary states – of which the psychedelic state is an exemplar.” Psychedelic-induced \nbrain activity would be associated with elevated entropy in some of its aspects with respect to \nnormal wakeful consciousness. This would indicate that psychedelic-induced brain activity would \nexhibit criticality, while normal wakeful consciousness would be subcritical. \nBut can entropy be a unique indicator of the “quality of consciousness?” Are there reasons to \nbelieve that psychedelic-induced activity is not critical?