A qualitative report on the subjective experience of intravenous psilocybin administered in an FMRI environment

This interview study (n=15) investigated the phenomenology of individuals under the acute influence of psilocybin (intravenously injected – quicker onset) in an fMRI scanner.

Abstract

“Background: This report documents the phenomenology of the subjective experiences of 15 healthy psychedelic experienced volunteers who were involved in a functional magnetic resonance imaging (fMRI) study that was designed to image the brain effects of intravenous psilocybin.

Methods: The participants underwent a semi-structured interview exploring the effects of psilocybin in the MRI scanner. These interviews were analysed by Interpretative Phenomenological Analysis. The resultant data is ordered in a detailed matrix, and presented in this paper.

Results: Nine broad categories of phenomenology were identified in the phenomenological analysis of the experience; perceptual changes including visual, auditory and somatosensory distortions, cognitive changes, changes in mood, effects of memory, spiritual or mystical type experiences, aspects relating to the scanner and research environment, comparisons with other experiences, the intensity and onset of effects, and individual interpretation of the experience.

Discussion: This article documents the phenomenology of psilocybin when given in a novel manner (intravenous injection) and setting (an MRI scanner). The findings of the analysis are consistent with previous published work regarding the subjective effects of psilocybin. There is much scope for further research investigating the phenomena identified in this paper.”

Authors: Samuel Turton, David J. Nutt & Robin L. Carhart-Harris

Summary

The use of rating scales limits the opportunity to report uncommon or unexpected effects, and stereotypes the effect description between individuals. Furthermore, experiences in unusual settings, such as a scanner environment, may not be sufficiently described by these rating scales.

Psilocybin has been documented to cause visual disturbances, hallucinations, loss of attention to outside stimuli, changes in time perception, altered mood, changes in thought and memory, and mystical or spiritual experiences.

Psilocybin experiences can have long-term personal meaning for participants, and may cause lasting personality changes. The intensity and nature of the experienced drug effects are poorly predicted by drug dose, and may be influenced by psychological and environmental factors.

Recent research into the effects of psilocybin in humans has used PET and fMRI to collect quantitative data on experience. These studies have shown increased anxiety in participants receiving psilocybin in a scanner environment.

15 psychedelic-drug experienced volunteers took part in an fMRI experiment in which they were injected with psilocybin. Their subjective experiences are described, and similarities and differences in subjective effects are highlighted.

Methods

Fifteen volunteers were recruited via word of mouth and underwent a thorough medical examination, including a full medical history, physical examination, routine blood tests, and urine test for drugs of abuse and pregnancy. They completed the State Trait Anxiety Inventory and the Beck Depression Inventory.

Each participant underwent two consecutive fMRI scans separated by at least 7 days. They were given psilocybin or placebo over 60 seconds and were required to complete a 0-10 visual analogue scale task.

Participants received saline during the first scan (placebo), and 2mg psilocybin during the second scan. They were blinded as to which scan was a placebo scan, and which scan was the psilocybin scan.

Participants were instructed to relax and focus on the displayed fixation cross during their psilocybin and placebo scans. They were also given the opportunity to ask any further questions regarding safety in the scanner.

All participants were interviewed following the second scan, and were asked questions based on the visual analogue scale they had completed in the scanner. They were also invited to elaborate on any other aspects of the experience raised during the interview.

Interviews were analysed using Interpretative Phenomenological Analysis (IPA), a qualitative method that focuses on exploring human experience rather than testing hypotheses.

Early proponents of phenomenology included Husserl, who developed transcendental phenomenology. Interpretative phenomenology recognises that the use of language to describe an experience is inevitably an interpretative process, and that both research participants and researchers are unable to fully exclude past knowledge and experience.

The researcher transcribed each interview, created descriptive and interpretative commentaries, associations, comments on language use and descriptive labels, and then created themes from each participant’s data. These themes were compared and combined with those from all other participants, and ordered in a matrix.

Reflexive Practice

The researcher analysing the qualitative reports had prior knowledge of the previous published research in psychedelic drugs and the effects of psilocybin, and had undergone a task based functional MRI scan to allow a degree of understanding of the scanner environment.

Results

The Onset and Intensity of the Effects

All participants reported rapid onset of drug effects, which gradually subsided over 10-15 minutes. However, all participants were still mildly affected by the drug during the interviews.

The reported intensity of the effects varied between two and seven. All reported that the effects came in intermittent ‘waves’, with periods of intense effects alternating with periods of comparative normality.

Perceptual Effects

Altered somatosensory, visual, auditory and proprioceptive sensations were reported in all participants, and one participant described a positive mood change as the main effect.

Seven participants reported distortions in the sounds of the scanner, and five reported that the scanner sounds were influencing their visual hallucinations.

Ten participants reported a change in their sense-of-self. Most had difficulty expressing this experience in words.

Nine participants reported a degree of loss of control over their thoughts, although most had difficulty expressing what this meant.

One participant described active control in directing the experience, while others described laughter and euphoria. All participants reported some sense of anxiety in anticipation of the drug effects, but this resolved following the onset of the drug effects.

Effect of Memories

Eleven participants reported no thoughts of their past during the experience, one reported a significant autobiographical recollection related to a distressing memory, and overall one participant summarised his experience as positive.

Surroundings and Environment

The scanner environment was described as strange, enclosed, machine, tube, womb-like and claustrophobic by eleven participants. One participant described the scanner as warm, safe and nice.

All participants described the fixation cross as being the focus of their visual hallucinations, and nine stated a preference for a more ‘natural’ setting. Five participants expressed concerns about ‘ruining’ the experiment or difficulty completing the rating scales.

Spiritual or Mystical Experiences

Six participants reported difficulties differentiating between terms such as ‘mystical’, ‘spiritual’ and ‘magical’, and nine participants described spiritual aspects of their experience.

Six participants reported a decreased likelihood of a spiritual experience, three explained why, and five reported a religious significance.

Discussion

15 research participants experienced a variety of phenomenological changes following administration of intravenous psilocybin while in an fMRI scanner. These experiences were consistent with previous literature on psilocybin and Altered States of Consciousness.

Most participants had difficulty describing certain aspects of the psilocybin experience, and many made comparisons between the psilocybin experience and other drug and non-drug induced altered states of consciousness.

Participants described mystical or spiritual aspects of the experience in different ways. Some participants explicitly stated that the research environment decreased the likelihood of having a spiritual experience, while others said that the experience would have spiritual meaning otherwise.

Participants described how their belief systems and cultural background influenced how they interpreted certain aspects of their experience. This was particularly evident in the descriptions of the fixation cross, which was associated with religious symbolism in Western Europe.

Participants may have been primed to report positive effects by completing the Visual Analogue Scale four times in each scan, and by discussing their experience with a researcher whilst being recorded with a video camera.

All participants experienced some residual effects of psilocybin during the interview, albeit at a much-reduced intensity compared to the peak effects. The majority consensus was that the scanner environment is not ideal for experiencing the effects of psilocybin, possibly diminishing positive effects and spiritual or mystical qualities.

The broad research question and unfocussed interview questions do not provide detailed data relating to any specific single aspect of the experience, but rather identify the major important categories of the experience and the phenomenological themes within.

This study identified certain key effects that are reproducible between subjects, and also reported on a wider range of potential individual effects.

The functional MRI results from this study indicated reduction in cerebral blood flow in both cortical and subcortical and cortical regions, which may be the reason why alteration of the function of these brain regions causes the profound and unusual effects on consciousness described in this report.

This study identified several key phenomena of intravenous Psilocybin within an MRI scanner. It has identified a large area for future research, including further exploration of the Psilocybin experience.