Psilocybin occasioned mystical-type experiences
| Thomas L Robertshaw
| Mathew Hoskins
| Ben Sessa
School of Pharmacy and Pharmaceutical
Sciences, Cardiff University, Cardiff, UK
Division of Psychological Medicine and
Clinical Neurosciences, School of Medicine,
Cardiff University, Cardiff, UK
Cardiff and Vale University Health Board,
Neuropsychopharmacology Unit, Department
of Medicine, Imperial College London,
Edward James, School of Pharmacy and
Pharmaceutical Sciences, Cardiff University,
King Edward VII Avenue, Cardiff, Wales CF10
Ben Sessa, Neuropsychopharmacology Unit,
Department of Medicine, Imperial College
London, London W12 0NN, UK.
Objective: Research into psychedelic therapy models has shown promise for the
treatment of specific psychiatric conditions. Mystical-type experiences occasioned
by psilocybin have been correlated with therapeutic benefits and long-term improve-
ments in positive mental outlook and attitudes. This article aims to provide an over-
view of the topic, highlight strengths and weaknesses in current research, generate
novel perspectives and discussion, and consider future avenues for research.
Design: This narrative review was designed to summarise and assess the state of
research on psilocybin occasioned mystical-type experiences and applications for the
treatment of specific psychiatric conditions.
Results: Contemporary methods on the quantification of mystical-type experiences and
their acute subjective effects are discussed. Recent studies provide some understanding of
the pharmacological actions of psychedelics although the neurological similarities and dif-
ferences between spontaneous and psychedelic mystical-type experiences are not well
described. Applicability to modern clinical settings is assessed. Potential novel therapeutic
applications include use in positive psychology interventions in healthy individuals.
Conclusions: Since 2006 significant advancements in understanding the therapeutic
potential of psilocybin-assisted psychotherapy have been made; however, more work is
required to understand the neuromechanistic processes and applicability in modern clinical
settings. Despite promising results in recent studies, funding issues for clinical trials, legal
concerns and socio-cultural resistance provide a counterpoint to experimental evidence.
Psilocybin, mystical-type experiences, psychotherapy, clinical applications, quantum change,
After 100 years of modern psychiatry, there remains a lack of consis-
tency in the provision of effective services for people with mental
health disorders. While the popular media often present a negative,
stigmatising picture of mental disorders and a lack of effectiveness of
treatments (Stuart, 2006), large meta-analyses have demonstrated
that in reality psychiatric treatments—when delivered appropriately
by well-resourced services—are comparable in efficacy to general
medical interventions (Seemüller, Möller, Dittmann, & Musil, 2012).
The negative perception persists, nevertheless, with particular empha-
sis placed on the potential adverse impact of the pharmaceutical
industry, which has prompted significant criticism (Greenberg, 2010).
Polypharmacy (the use of two or more medications to treat the
same illness) is often observed and is frequently associated with a lack
of efficacy and increased harms from combining multiple drug
Received: 15 November 2019 Revised: 2 May 2020 Accepted: 11 May 2020
This is an open access article under the terms of the Creative Commons Attribution-NonCommercial License, which permits use, distribution and reproduction in any
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Hum Psychopharmacol Clin Exp. 2020;e2742. wileyonlinelibrary.com/journal/hup © 2020 John Wiley & Sons Ltd 1of8
treatments (Kukreja, Kalra, Shah, & Shrivastava, 2013). Polypharmacy is
especially the case when lack of attention is paid to the provision of
non-drug, psychosocial interventions—especially outpatient psychother-
apy (Mojtabai & Olfson, 2008). In this context, what has emerged in the
last 50 years of biological psychiatry is an urgent need to rationalise
pharmacological treatments and bolster the efficacy and efficiency of
psychotherapies. It is into this environment that psychedelic-assisted
psychotherapies are becoming increasingly explored as viable innovative
approaches for the future of psychiatry (Sessa, 2012).
The prodrug psilocybin, from Psilocybe mushrooms (Figure 1), is dem-
onstrating therapeutic potential for the treatment of psychiatric con-
ditions including alcohol use disorder (Bogenschutz et al., 2015),
tobacco addiction (Garcia-Romeu, Griffiths, & Johnson, 2014), depres-
sion (Carhart-Harris et al., 2016) and existential anxiety in palliative
care (Griffiths et al., 2016; Grob et al., 2011; Ross et al., 2016). In
many of these clinical studies, subjects' mystical-type experiences
have been correlated with therapeutic outcomes and improvements
in various aspects of mental well-being such as reductions in anxiety
and an increase in the personality domain of openness (Griffiths
et al., 2016; Johnson, Garcia-Romeu, & Griffiths, 2017; MacLean,
Johnson, & Griffiths, 2011).
In 2006 a Roland Griffiths publication reported that “psilocybin
can occasion mystical-type experiences having substantial and
sustained personal meaning and spiritual significance”(Griffiths,
Richards, McCann, & Jesse, 2006). Since then, a number of
psilocybin-assisted psychotherapy studies have been conducted
which employ experimental features such as randomisation and
double-blind crossover designs to mitigate the effects of expectation
in both participants and clinicians (Griffiths et al., 2016; Ross
et al., 2016). While double-blinding in a clinical trial for psychedelic
therapy presents inherent challenges the long-term enduring effects
have been recorded to discern the applicability of psychedelic expe-
riences as a form of psychiatric therapy (Barnby & Mehta, 2018).
Contemporary research indicates that if medical health care profes-
sionals could reliably induce psychedelic experiences of an insightful
and mystical-type nature eliciting sudden, dramatic and enduring
transformations that affect personal emotion, cognition and behav-
iour (a phenomenon referred to as quantum change) then there
could be improvements in public health and well-being (Griffiths
et al., 2018; Griffiths, Richards, Johnson, McCann, & Jesse, 2008;
Johnson, Hendricks, Barrett, & Griffiths, 2019; Miller, 2004).
Effects of psilocybin on cognitive processes and mental function-
ing of a participant during a psilocybin trial are typically measured by
inviting the participant to complete validated questionnaires such as:
5-Dimension Altered States of Consciousness; the States of Con-
sciousness Questionnaire (SOCQ); and the Mystical Experience Ques-
tionnaire (Barrett, Johnson, & Griffiths, 2015; Griffiths et al., 2016;
MacLean, Leoutsakos, Johnson, & Griffiths, 2012; Maji
c, Schmidt, &
Gallinat, 2015). In order to determine whether a participant has had a
“complete mystical-type experience”the results of questionnaires are
totalled rendering a score—such as 60% on each subscale of the
SOCQ (MacLean et al., 2011). The core phenomenology of mystical
experiences, as described by previous work, include feelings of unity
and interconnectedness with all people and things, a sense of sacred-
ness, feelings of joy, peace and awe, a sense of transcending normal
time and space, ineffability and an intuitive belief that the experience
is a source of objective truth about the nature of reality (Griffiths
et al., 2006, 2018; James, 1902; Kundi, 2013; MacLean et al., 2011;
Roseman, Nutt, & Carhart-Harris, 2018; Stace, 1960).
3|PSYCHEDELIC AND NON-
PSYCHEDELIC MYSTICAL EXPERIENCES
The results of recent studies into both psychedelic-induced and non-
psychedelic-induced mystical experiences suggest that mystical expe-
riences are “biologically normal”(Griffiths et al., 2011) and can occur
in both religious and non-religious individuals (Yaden et al., 2017).
Studies suggest that mystical experiences and quantum change can
occur in non-drug conditions with reports of spontaneous occur-
rences in times of crisis or stagnation (Miller, 2004). While subjective
effects of psychedelic and non-psychedelic-induced mystical
FIGURE 1 Wild Psilocybe semilanceata
2of8 JAMES ET AL.
experiences differ, there are certain similarities such as the sense of
transcendence of time and space which imply there are continuities
between the psychological states (Yaden et al., 2017). In the case of
mystical experiences induced through disciplined contemplative prac-
tices an individual is typically required to spend months or years train-
ing their mind in order to reliably occasion meaningful mystical
experiences (Kundi, 2013). While in the case of psychedelic-induced
mystical-type experiences, research suggests that the quality of the
experience is improved while the probability of occurrence is also
increased enabling this generally rare state to become more readily
accessible (Winkelmann, 2017; Yaden et al., 2017).
3.1 |Cultural debate about the validity of
psychedelic-induced mystical-type experiences
The subject of psychedelics' place in the study of comparative reli-
gions has been well explored by the likes of Alan Watts (Watts, 1968)
and Aldous Huxley (Huxley, 1954). But from the beginning of dis-
course on the subject there were opposing viewpoints. Following
Huxley's widely read description of his mescaline experience in 1953
there came a rebuttal from other academics, notably Professor Robert
Zaehner, who warned of the dangers of conflating the transient, drug-
induced psychedelic state with attainment of mystical states through
non-drug religious experiences (Zaehner, 1957). The debate increased
as the 1960s progressed and whilst Zaehner later agreed that drug-
induced states could provide some useful guidance towards leading a
spiritual life he also highlighted examples of the misuse of psychedelic
spirituality and its capacity to do harm (Zaehner, 1974).
This article focuses on the capacity of psilocybin to induce acute
mystical-type and insight experiences which can mediate persisting
changes in perspective and psychological well-being. While mystical
experiences can occur spontaneously in non-drug conditions and the
reported subjective effects and long-term alterations of the two types
are comparable, the two experiences are not the same due to differing
Psilocin, the pharmacologically active dephosphorylated metabolite of
psilocybin, is highly structurally related to serotonin with a dimethyl
tertiary amine as opposed to a primary amine on the two carbon ali-
phatic chain and a hydroxyl group at the 40carbon as opposed to the
50carbon on the indole phenyl ring being the sole differences in the
chemical structures of psilocin and serotonin (Figure 2). Psilocin is a
functional agonist of the G protein-coupled 5-HT
tors and modulation of these receptors has been implicated in neuro-
plasticity, environmental sensitivity, learning and psychological
adaptability (Carhart-Harris et al., 2018b; Carhart-Harris &
Nutt, 2017; Erritzoe et al., 2019).
Research suggests that psychedelics mediate their subjective
effects partly by decreased connectivity within the default mode
network (DMN) (Johnson et al., 2019; Speth et al., 2016;
Winkelmann, 2017), modulation of the anterior and posterior cingu-
late cortex (Carhart-Harris, Leech, Williams, et al., 2012) and whole
brain integration (Hendricks, 2018). The subjective mystical-type
effects of psilocybin including ego dissolution have been at least par-
tially attributed to disruption of the DMN (Griffiths et al., 2006). Psy-
chedelics down-regulate expression of 5-HT
receptors in the
prefrontal cortex (Hendricks, 2018); and subjective effects of psyche-
delics may result from 5-HT
receptor-mediated excitation of deep
pyramidal cells leading to a desynchronization of oscillatory rhythms
in the cortex (Muthukumaraswamy et al., 2013). Disruption of the pre-
frontal cortex allows ancient brain systems such as the mirror neuron
system (Winkelmann, 2017), which is located in numerous cortical
regions, to occupy a more central role in subjective awareness
(Rizzolatti & Sinigaglia, 2016). Current research into the effects of psi-
locybin on brain function suggests an increase in communication
between brain networks accompanied by a decrease in communica-
tion within those networks (Hendricks, 2018).
The function of brain serotonin is reportedly “an enigma”
(Carhart-Harris & Nutt, 2017) and the exact role of 5-HT
nin receptor signalling and how it relates to both psilocybin
occasioned mystical-type experiences and naturally occurring
spontaneous mystical experiences is poorly understood (Barnby &
Mehta, 2018; Carhart-Harris & Nutt, 2017). Conducting controlled
experiments to elucidate the neuromechanistic similarities and dif-
ferences between the two types of experience presents significant
challenges due to the difficulty of eliciting spontaneous mystical
experiences in experimental settings.
4.1 |Sensitivity to meaning response
Psychotherapeutic benefits of psilocybin are not reportedly as depen-
dent on dose or intensity of drug effect as they are dependent on the
quality of the experience (Carhart-Harris, Roseman, et al., 2018;
Griffiths et al., 2006; Roseman et al., 2018). While expectation and
mood play a role in the therapeutic effects of all therapies, through
the innate placebo and nocebo effects universal to all forms of medi-
cal treatment, psychedelics render the participant especially sensitive
to the effects of set (the psychological mind-set in the build up to the
experience including expectations and intentions) and setting (the
FIGURE 2 The chemical structures of psilocin and serotonin
JAMES ET AL.3of8
physical, social and political environment in which the experience
takes place) (Hartogsohn, 2016, 2017; Metzner, Litwin, & Weil, 1965).
It has been proposed that the effects of set and setting and the
placebo effect are not two differing extra-pharmacological compo-
nents which contribute to mediating effects of treatment but are both
expressions of meaning response. Meaning response is a broader con-
cept which includes the many ways in which extra-pharmacological
elements, including ritualistic and medical symbology, exert positive
and negative effects on health in a variety of contexts. Psychedelics
such as psilocybin are putative meaning response enhancers
suggesting that one of their modes of action is to directly enhance the
placebo effect itself. As potential magnifiers of the placebo response
patients' expectations of the outcome of treatment may be more fun-
damental to successful therapeutic outcomes than in other forms of
medical intervention (Hartogsohn, 2016). Furthermore, use of psilocy-
bin to induce psychological transformations may result in modification
of the epigenome via the enhanced placebo response (intent-oriented
gene expression modulation) (Carey, 2012; Martin & Nichols, 2017).
The psychological construct “awe”has been proposed to be a key
feature of spontaneous and psychedelic occasioned mystical-type
experiences. The experience of awe can lead to the sensation of the
“small self”—the feeling that one is small in comparison with the
cosmos—and this has been proposed as being a psychological media-
tor of mystical experience (Piff, Dietze, Feinberg, Stancato, &
Keltner, 2015). Individuals with high personality trait openness report-
edly demonstrate a greater capacity to experience awe as participants
who are able to fully absorb themselves in an external stimulus such
as music are more likely to experience “chills”—an indication of subjec-
tively experienced awe (Hendricks, 2018). Commonly reported elici-
tors of awe include the natural environment, art, music and religious/
spiritualistic imagery. Greater emotional sensitivity to the environ-
ment may facilitate enhanced feelings of connectedness (Carhart-
Harris et al., 2018a) and subjective effects of awe resulting in a psy-
chological mind-set more receptive to mystical-type experience.
4.2 |Improved psychological flexibility mediates
Recent studies have elucidated certain functional characteristics of a
model of psychedelic-induced quantum change. Mystical-type and
insight experiences as measured using validated questionnaires were
found to be highly correlated with one another while only indirectly
correlated with improved psychological well-being. Regression ana-
lyses showed mystical-type and insight experiences to be highly cor-
related with improved psychological flexibility and feelings of personal
meaningfulness which in turn were highly correlated with improved
psychological outlook (Davis, Barrett, & Griffiths, 2020; Garcia-Romeu
et al., 2019; Garcia-Romeu et al., 2020). Therefore, these studies sug-
gest that it is the improved psychological flexibility and personal
meaningfulness associated with mystical-type and insight experiences
which enables depressed and anxious individuals and people with sub-
stance use disorders to reframe how they view their medical
conditions, themselves, their lives and relationships with others
(Belser et al., 2017; Davis et al., 2020; Garcia-Romeu et al., 2019,
2020; Spiegel, 2016; Watts, Day, Krzanowski, Nutt, & Carhart-
5|PATIENT APPLICABILITY OF
MYSTICAL-TYPE EXPERIENCES IN
“Siempre se tomaron para que los enfermos sanaran (They were
always taken to cure the sick)”- Maria Sabina (Estrada, 1977)
As psilocybin is a putative meaning response enhancer, it is
important that the medical health care profession inspires confidence
that the treatment will be effective otherwise critical attitudes
towards psilocybin use and mystical-type experiences among the gen-
eral population may impair therapeutic efficacy (James et al., 2019).
Preconceptions in any treatment will impact its efficacy as demon-
strated by the fact that the placebo effect is different across cultures
and personality types (Hartogsohn, 2016). The attitudes of partici-
pants in psilocybin trials are key to successful therapeutic outcomes
as participants should reportedly have a desire to improve their condi-
tion, demonstrate a “clear intention and an open, enquiring attitude”
and be willing to “surrender”to the experience (Carhart-Harris
et al., 2018b; Russ, Carhart-Harris, Maruyama, & Elliot, 2019). In addi-
tion, trait absorption which is correlated with openness to experience
has been indicated as being the second strongest predictor of
mystical-type experience after drug dose (Hendricks, 2018; Studerus,
Gamma, Kometer, & Vollenweider, 2012).
Consequently, inducing mystical-type experiences as a form of
treatment is primarily likely to apply to specific groups of patients
such as the types of patients who are currently included in psilocy-
bin studies. These patients seek psilocybin treatment because they
think it will help them and often on the basis of past experience.
Additionally, many of the participants in psilocybin trials who report-
edly meet the criteria for a complete mystical-type experience regu-
larly engage in some form of spiritual practice (MacLean
et al., 2011). Patients high in personality trait neuroticism may be
less likely to benefit from psilocybin (Studerus et al., 2012). Patients
currently taking medications prescribed to treat a range of psychiat-
ric conditions such as tricyclic antidepressants, lithium, selective
serotonin reuptake inhibitors, monoamine oxidase inhibitors and the
antipsychotic medication haloperidol are typically excluded from psi-
locybin trials due to impaired psychopharmacological effects of psi-
locybin (Johnson, Richards, & Griffiths, 2008). These patients would
likely need to go through a period of abstinence from their medica-
tions prior to psilocybin-assisted psychotherapy and such a require-
ment demands individual assessment to determine if the potential
risk to reward is acceptable.
Due to clinical literature and case reports of psychedelics (typi-
cally LSD) inducing prolonged psychoses, patients with psychotic dis-
orders and people with a family history of psychotic disorders or
bipolar disorder are currently excluded from psilocybin trials (Johnson
4of8 JAMES ET AL.
et al., 2008; Ross et al., 2016). Psilocybin can induce periods of anxi-
ety, fear, panic, paranoia, sadness, depressed mood, anger, loss of san-
ity, delusions, dysphoria, perceptual effects and physiological
symptoms (e.g., nausea and increased heart rate). Patients with disor-
ders on the psychotic spectrum may be at increased risk of suffering
paranoia whilst experiencing the effects of psilocybin (Johnson
et al., 2008). Overwhelmingly difficult challenging experiences while
under the influence of psychedelics can lead to dangerous behaviour
such as leaving the study site and patients attempting to cause physi-
cal harm to themselves or others—with rare reports of attempted sui-
cides. Challenging experiences have also been associated with
apparent onset of psychotic symptoms although prolonged psychoses
are rare and typically dissipate within 48 hr (Carbonaro et al., 2016;
Johnson et al., 2008).
Groups of patients with psychotic illnesses such as schizophrenia,
schizoaffective disorder, bipolar affective disorder, delusional disorder
and severe depression with psychosis present significant complica-
tions to an already complex treatment model. Great care should be
taken when considering psychedelic treatment for individuals in these
groups to minimise the potential psychedelics have for exacerbating
psychotic symptoms (Barrett, Bradstreet, Leoutsakos, Johnson, &
Griffiths, 2016; Carbonaro et al., 2016). This risk may also translate to
populations who are at high risk for developing psychosis. While the
established wisdom is that psychedelics are contraindicated for indi-
viduals with a family history of psychosis; studies have suggested that
psychedelics are not demonstrated to cause lasting anxiety, depres-
sion or psychosis and are associated with reduced negative mental
health outcomes (Johnson et al., 2008; Krebs & Johansen, 2013). It
could be that some patients currently excluded from psilocybin trials
are not at significant risk from psilocybin use although there is no con-
sensus on the issue of psychedelic use and psychosis and further
research is warranted (Nesvag, Bramness, & Ystrom, 2015).
Investigations of challenging psychedelic experiences have shown
a majority of individuals attribute increased life satisfaction to the
event, and while the duration of the challenging experience has been
negatively correlated with enduring increased well-being, increased
life satisfaction is reportedly positively and significantly related to the
difficulty of a psychedelic experience. As such it has been suggested
that therapeutic interventions should focus on reducing the duration
of a challenging experience rather than reducing its peak difficulty
(Barrett et al., 2016; Carbonaro et al., 2016).
EXPERIENCES AS A MEDICAL TREATMENT
A considerable amount of time is spent on the preparation and moni-
toring of the participants for psilocybin-assisted psychotherapy in
order to ensure an acceptable level of safety and efficacy of
Patients meet with monitors (also referred to as guides) on sev-
eral occasions and visit the site where the experience will take place
so that they are comfortable in that environment. Monitors are
typically a female–male dyadic pair although male–male and female–
female dyads have also been utilised (Eisner & Cohen, 1958; Johnson
et al., 2008). Participants are required to establish rapport with the
monitors and the monitors should demonstrate supportive clinical
sensitivity such as empathy and respect (Johnson et al., 2008). In
recent studies participants are encouraged to wear a mask over their
eyes, relax, listen to music and focus their attention inward while
being monitored throughout the usual 7- to 8-hr session (Belser
et al., 2017; Johnson et al., 2008; Kaelen et al., 2018). Due to the
afterglow effect and the potential long-term therapeutic window of
psilocybin it may be possible to enhance the benefits of mystical-type
experiences by preliminary and follow up activities. Meditation, mind-
fulness or other spiritual practices combined with exposure to stimuli
that maintain awe such as nature, art and music are potential
approaches to maintaining and enhancing the long-term benefits of
mystical-type experiences (Brewer et al., 2011; Griffiths et al., 2018;
Some patients such as meditation and hallucinogen-naive individ-
uals are likely to require more extensive preparation than others
(Studerus et al., 2012). It will be challenging to adapt psychedelic ther-
apy to already overstretched public health care services and psyche-
delic therapy may initially be adopted as a form of private health care.
However, the psychedelic treatment model, while costlier in terms of
delivery in comparison with conventional therapies for mental illness,
may ultimately be cost-saving in certain situations where individuals
with severe and treatment-resistant anxiety, depression and trauma-
related conditions could be saved years of conventional treatment by
a course of controlled and supported psychedelic therapy sessions
(Carhart-Harris et al., 2018b).
7|FUTURE DIRECTIONS FOR
7.1 |Alternative applications of mystical-type
Research has suggested that psilocybin use can lead to positive changes
in personality and increased altruism such as enhanced nature-
relatedness (Lyons & Carhart-Harris, 2018), pro-environmental behav-
iour (Forstmann & Sagioglou, 2017), decreased violent and criminal
behaviour (Hendricks et al., 2018; Walsh et al., 2016), reduced suicidal
ideation (Hendricks, Thorne, Clark, Coombs, & Johnson, 2015), tem-
pered politically authoritarian views (Lyons & Carhart-Harris, 2018) and
an increase in the personality domain of openness (MacLean
et al., 2011; Nour, Evans, & Carhart-Harris, 2017). In light of the previ-
ously highlighted research, it could be argued that use of psilocybin in
positive psychology interventions to induce changes in domains of per-
sonality could have benefits to society and the global environment
(Elsey, 2017; James, Robertshaw, & Westwell, 2019; Shelton &
Hendricks, 2016; Watts et al., 2017).
Psychedelics have been used to attempt to treat narcissistic per-
sonality disorder due to their effects on the ego (Maji
c et al., 2015).
JAMES ET AL.5of8
Spontaneously occurring quantum change experiences have been
associated with reduced egotistical attitudes and greater prosocial dis-
position (Miller, 2004). Using psilocybin to induce mystical-type expe-
riences may be beneficial for individuals who excessively ruminate on
the self. With the continually rising prevalence of social media and the
reported crisis of meaning within society (Roberts, 2007), psilocybin's
effects on the ego and connectedness could be of use to the mental
healthcare profession (Carhart-Harris, 2018a).
7.2 |Clinical settings
The emergence of evidence-based psychedelic-assisted therapies will
present new opportunities and challenges for existing health care sys-
tems; many aspects of psychedelic-assisted therapies will look familiar
to doctors, nurses and therapists, with drug-free preparation sessions
and integration sessions requiring little change from the logistics of
usual practice. However, drug-assisted sessions are novel and will
require specially dressed and comfortable rooms, the use of music,
supportive and reassuring interaction, the presence of two therapists,
overnight stays with night sitters in most cases and intensive clinical
contact in between sessions. In some circumstances purpose-built
facilities may be more suitable than using existing infrastructure.
In the long-term, in order for psilocybin treatment to become
established practice, rescheduling from Schedule I needs to be
achieved and specific training for psychedelic therapy must be devel-
oped, standardised and licensed to maintain patient safety and effi-
cacy of treatment (Carhart-Harris et al., 2018b; Rucker, Iliff, &
Nutt, 2018). Despite the growing awareness of their potential thera-
peutic capabilities many regulatory authorities continue to consider
these compounds to be controversial (Nutt, 2014). Such opinions
threaten to hold back clinical research and deny patients the thera-
peutic potential of psychedelics. In addition, as psilocybin is a natural
product the issues surrounding intellectual property mean that the
investment route for progression through clinical trials and eventual
approval by the FDA and EMA is challenging. Therefore, the funding
for clinical trials will likely have to come via charitable or non-profit
Whilst this article has focused on mystical-type experiences and
applicability for the treatment of specific conditions, it is worth noting
that alternative treatment modalities such as microdosing may have
therapeutic value and the treatment of obsessive compulsive disorder
and cluster headaches are reported to be a result of pharmacological,
rather than psycho-spiritual, mechanisms (Cameron, Benson, DeFelice,
Fiehn, & Olson, 2019; Maji
c et al., 2015). Psilocybin occasioned
mystical-type experiences represent an intriguing novel form of treat-
ment; however, the cognitive and neural mechanistic processes are
not well understood (Barnby & Mehta, 2018; Lieberman &
Shalev, 2016). Correlation does famously not equal causality and
although current evidence suggests that inducing experiences of a
highly “mystical”nature could lead to novel forms of psychiatric treat-
ment, more work is needed to inform the psychiatry profession on
how to reliably induce such experiences in clinical settings.
This research received no specific grant from any funding agency,
commercial or not-for-profit sectors.
CONFLICT OF INTEREST
Dr Hoskins has received MDMA-assisted therapy training and travel
expenses from the Multidisciplinary Association for Psychedelic Stud-
ies (MAPS), and is a principal investigator on a MAPS sponsored phase
II clinical trial of MDMA.
Dr Sessa is Managing Director of Mandala Therapy Ltd and has
authored and co-authored several books on psychedelics for which he
Edward James https://orcid.org/0000-0002-9158-0762
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How to cite this article: James E, Robertshaw TL, Hoskins M,
Sessa B. Psilocybin occasioned mystical-type experiences.
Hum Psychopharmacol Clin Exp. 2020;e2742. https://doi.org/
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