Psilocybin

Dimensions of consciousness and the psychedelic state

This theoretical review (2018) critically analyzes whether psychedelic-induced experiences constitute a higher state of consciousness and argues that a unidimensional mode of classification is not appropriate, given that there are multiple ways in which altered states of consciousness may be ‘higher’ or ‘lower’ from one another across multiple dimensions.

Authors

  • Olivia Carter

Published

Neuroscience of Consciousness
meta Study

Abstract

Introduction

It has often been suggested in the popular and academic literature that the psychedelic state qualifies as a higher state of consciousness relative to the state of normal waking awareness. This article subjects this proposal to critical scrutiny, focusing on the question of what it would mean for a state of consciousness to be ‘higher’.

Methods

We begin by considering the contrast between conscious contents and conscious global states. We then review the changes in conscious global state associated with psychedelic drug use, focusing on the effects of two serotonergic hallucinogens: psilocybin and lysergic acid diethylamide. Limiting our review to findings obtained from lab-based experiments and reported in peer-reviewed journals, we prioritize the more common and reliably induced effects obtained through subjective questionnaires and psychophysical measures.

Results

The findings are grouped into three broad categories (sensory perception, cognitive function, and experiences of unity) and demonstrate that although certain aspects of consciousness are improved or enhanced in the psychedelic state, many of the functional capacities that are associated with consciousness are seriously compromised.

Discussion

Psychedelic-induced states of consciousness are indeed remarkable in many ways, but it is inappropriate to regard them as ‘higher’ states of consciousness. The fact that psychedelics affect different aspects of consciousness in fundamentally different ways provides evidence against the unidimensional (or ‘level-based’) view of consciousness, and instead provides strong support for a multidimensional conception of conscious states. The final section of the article considers the implications of this analysis for two prominent theories of consciousness: the Global Workspace Theory and Integrated Information Theory.

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Research Summary of 'Dimensions of consciousness and the psychedelic state'

Introduction

Bayne and colleagues open by drawing a standard distinction in consciousness science between the 'contents of consciousness' (the particular things one is conscious of) and 'states of consciousness' (global conditions that shape which contents can appear and how they are used). They note that while contents are relatively well characterised, the notion of a conscious state is less settled and is often framed in terms of unidimensional "levels of consciousness"—a framing the authors question because it assumes all states can be placed on a single ordered scale. This paper sets out to examine how the psychedelic state, as induced by two serotonergic hallucinogens (psilocybin and LSD), bears on the prospect of treating conscious states as higher or lower relative to ordinary waking awareness. Focusing on subjective reports and psychophysical measures obtained in lab-based, peer-reviewed studies, Bayne and colleagues aim to determine whether psychedelic-induced changes support the idea of a single dimension of consciousness or instead favour a multidimensional conception. They organise the empirical literature into three domains—sensory/perceptual experience, cognitive function, and experiences relating to time, self and space—and use these to assess whether the psychedelic state can plausibly be described as "higher."

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Study Details

References (23)

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