ArticlePDF Available

Four individuals' experiences during and following a psilocybin truffle retreat in the Netherlands


Abstract and Figures

This article reports on the experiences of four healthy individuals who attended a legal psilocybin truffle retreat in the Netherlands. The study employed a qualitative phenomenological approach, using semi-structured interviews to gain an understanding of participants' psilocybin experiences and their after-effects. The experiential themes that emerged from these case studies closely match themes that have been identified in previous studies of psilocybin, including variability of the experience, the presence of mystical-type features, significant changes to subjective sense of self, and a generalized sense of connectedness. Participants framed their narrative accounts around moments of key insight, and these insights were related to a sense of connection: to self, others, and to a broader relational ontology. Embodiment, currently an understudied topic in psychedelic research, also emerged as a theme. The case studies presented here provide preliminary evidence to suggest that for healthy individuals in a well-controlled and supportive retreat setting, a high dose of psilocybin can lead to enduring positive after-effects that last up to twelve months.
Content may be subject to copyright.
Four individualsexperiences during and
following a psilocybin trufe retreat in the
The University of Sydney, Australia
Received: November 9, 2020 Accepted: February 22, 2021
This article reports on the experiences of four healthy individuals who attended a legal psilocybin truffle
retreat in the Netherlands. The study employed a qualitative phenomenological approach, using semi-
structured interviews to gain an understanding of participantspsilocybin experiences and their after-
effects. The experiential themes that emerged from these case studies closely match themes that have
been identied in previous studies of psilocybin, including variability of the experience, the presence of
mystical-type features, signicant changes to subjective sense of self, and a generalized sense of
connectedness. Participants framed their narrative accounts around moments of key insight, and these
insights were related to a sense of connection: to self, others, and to a broader relational ontology.
Embodiment, currently an understudied topic in psychedelic research, also emerged as a theme. The
case studies presented here provide preliminary evidence to suggest that for healthy individuals in a
well-controlled and supportive retreat setting, a high dose of psilocybin can lead to enduring positive
after-effects that last up to twelve months.
Studies suggest that the psychedelic compound psilocybin may be an effective treatment for a
variety of clinical issues, including treatment-resistant depression (Roseman, Nutt, & Car-
hart-Harris, 2018), anxiety and depression related to advanced stage cancer (Grifths et al.,
2016; Ross et al., 2016), obsessive compulsive disorder (Moreno, Wiegand, Taitano, & Del-
gado, 2006), tobacco use disorder (Garcia-Romeu et al., 2014; Johnson, Garcia-Romeu,
Cosimano, & Grifths, 2014, Johnson, Garcia-Romeu, & Grifths, 2017) and alcohol use
disorder (Bogenschutz et al., 2015, 2018). Psilocybin has also been associated with positive
outcomes in healthy individuals. For example, a recent study by Madsen et al., 2020 found
that a single dose of psilocybin had long lasting benecial effects on mood, personality, and
mindfulness in healthy volunteers. Additionally, Mason et al. (2019) found that a single
administration of psilocybin in a social retreat setting may be associated with sub-acute
enhancement of creative thinking, empathy, and subjective well-being.
Currently the mechanisms of action underlying the positive effects of psilocybin are
unknown. Preliminary research suggests there are multiple mediators of action, and scholars
from various disciplines have approached the issue from a number of perspectives. For
example, some have focused on neuropharmacological mechanisms (e.g., Carhart-Harris &
Friston 2019; Carhart-Harris & Nutt 2017), while others have investigated psychological
change processes (e.g., Watts, Day, Krzanowski, Nutt, & Carhart-Harris, 2017). Several
studies have found that psilocybin occasioned mystical experiences are related to long term
benecial outcomes (e.g., Doblin, 1991; Grifths et al., 2018; Russ, Carhart-Harris, Mar-
uyama, & Elliott, 2019). Possible mediators of this effect include ego dissolution experiences
(e.g., Carhart-Harris et al., 2018), feelings of awe(James, Robertshaw, Hoskins, & Sessa,
2020), post-experience behavioral changes such as engagement with meditation and other
spiritual practices (Grifths et al., 2018), and signicant changes to beliefs and worldviews
Journal of Psychedelic
© 2021 The Author(s)
pCorresponding author.
Unauthenticated | Downloaded 04/17/21 01:12 AM UTC
such as decreased self-identied atheism (Davis et al., 2020;
Grifths et al., 2019) and increased nature-relatedness
(Lyons & Carhart-Harris, 2018). Additionally, Hartogsohn
(2018) has argued that psychedelics have a meaning-
enhancing effect, so that under the inuence of psychedelics,
things appear to be profoundly more meaningful than usual.
Recently, a number of qualitative studies have analyzed the
psilocybin experience; specifically, the phenomenology of the
experience, the meanings that people attribute to the experi-
ence, and how the experience might facilitate subsequent after-
effects (Belser et al., 2017; Bogenschutz et al., 2018; Malone
et al., 2018; Nielson et al., 2018; Noorani et al., 2018; Swift
et al., 2017; Turton, Nutt, & Carhart-Harris, 2014; Zamaria,
2016). Qualitative studies offer a hypothesis-generating mode
of inquiry that may help to reveal underlying mechanisms of
action and contribute to the development of theory. Such an
approach is valuable in the eld of psychedelic studies, where
theoretical models are still underdeveloped (Belser et al., 2017).
For example, in their systematic review of patient experiences
in qualitative studies, Breeksema et al. (2020) report that
qualitative psychedelic research may help to differentiate
specic features of specic substances, which has implications
for the treatment of specic psychiatric disorders.
In particular, qualitative case studies serve an important
epistemological function, as over time they accumulate into
a body of knowledge which can then guide clinical practice
and suggest where research should turn to next. Case studies
can be conducted at various points in the research process,
and they may be particularly useful at early stages (e.g. pilot
studies) as they can generate ideas for future research. The
other benefit of the case study is that it captures the lived
realityof an experience; case studies offer a rich and holistic
account of a phenomenon and allow the researcher to
explore the uniqueness of a single case (Simons, 2009).
This article reports on the experiences of four healthy
individuals who consumed a high dose of psilocybin con-
taining truffles at a legal retreat center in the Netherlands. The
case studies presented here derive from a larger qualitative
study that is currently examining the phenomenology of the
psilocybin experience among healthy volunteers in a retreat
setting. The case studies in this article were chosen because as
a sub-sample they adequately represent the key themes that
emerged from the entire data set.
These themes were iden-
tied by the researcher during the interview process and will
be further investigated and developed in future research via
thematic analysis. As such these case studies function as a
pilot study for a more in-depth analysis of the larger data set.
Participants were four volunteers who attended a three day
legal psilocybin retreat at Synthesis in the Netherlands,
between the months of September 2019 and February 2020.
All four participants (3 male, 1 female) self-identified as
Caucasian and ranged between 43 and 55 years of age (M 5
51). Participants were from Europe (n52), North America
(n51) and Central America (n51). Religious afliation
was Atheist (n51) and Spiritual But Not Religious (SBNR)
(n53). Reasons for attending the retreat included heal a
mental health condition (MH),
explore consciousness
(EC),”“personal development (PD),”“increase creativity
(IC),and have a mystical experience (ME).
Prior to the retreat, all participants went through an
extensive screening process, which included questionnaires
and an interview, to check for any pre-existing health con-
ditions that might preclude attendance, and to determine
psychological readiness. In order to optimize set and setting,
individuals had a number of online preparation sessions in
the weeks leading up to the retreat, a full day of preparation
the day before the psilocybin session (day one of the retreat),
and a half day of preparation the day of the psilocybin
session (day two of the retreat). Preparation activities
included pre-reading, meditation, breathwork, and one-on-
one sessions with an expert facilitator. After the psilocybin
session (on day three of the retreat and for several weeks
afterward), participants took part in a structured integration
program which addressed somatic and social integration.
During the psilocybin session all participants took one
high dose of psilocybin containing truffles (dose range 5
3040 g) in the form of a tea. About 90 minutes into the
session participants could elect to take a second booster
dose of trufes (an amount up to the same initial dose). One
participant in this cohort elected to take the booster dose.
None of the participants had used psilocybin or any other
psychedelics prior to the retreat. All participants had good
recall of the psilocybin experience and all reported enduring
positive after-effects that had persisted since the retreat.
Data was collected via a short online survey which gathered
some basic demographic information, and a semi-structured
interview of approximately 1 h duration. Each interview was
conducted via Zoom and took a story-telling approach,
which involves asking questions in such a way that partici-
pants respond with a story (Minichiello, Aroni, & Hays
2008, p. 95). The rationale for encouraging stories is that it
enables the interviewee to feel comfortable with talking for
extended periods, as stories are usually extended mono-
logues. Because a psychedelic experience is often a difcult
experience to describe, a loose structure was suggested.
Participants were told that they could tell the interviewer
about their experience in any way they liked, and that one
possible approach could be to (1) start by talking about what
n511 (at the time of writing).
While the Synthesis three day retreat is not explicitly aimed at healing
mental health conditions, and participants who have contraindicated
mental illnesses are excluded via a screening process, one participant
(Ben) reported that during his life he had experienced periods of mild to
moderate depression.
2Journal of Psychedelic Studies
Unauthenticated | Downloaded 04/17/21 01:12 AM UTC
brought them to the retreat, (2) describe the actual psilo-
cybin experience, and (3) describe their journey since the
retreat, including any signicant after-effects and changes.
All participants followed this general approach. Follow-up
questions were used for clarication and to probe for more
detail. Each interview was recorded and transcribed
verbatim. Three participants (Jay, Carol, and Ben) also
shared copies of journal entries that they had written
immediately after, or in the days following, the psilocybin
experience. All participant data was de-identied in order to
preserve anonymity. All individuals mentioned in this
article, including retreat staff members and individuals
mentioned in the narratives, have been given pseudonyms.
Jay was a male in his 50s, who worked as a journalist. Jay
had never taken a psychedelic before and said he found
Synthesis after googling psychedelic retreats in Europe, and
signed up on the spur of the moment.Going into the
retreat, Jay hoped to gain insight regarding his relationship
with fear and also regarding a creative block that he was
experiencing. Specically, Jay had been trying to write a
book for the past ten years but reported that It just wasn't
happening.Jay described himself as a very fact based
personwho also had a very spiritual side.
During the interview, Jay highlighted several salient in-
cidences that occurred during the psilocybin experience.
One of these was a breakthrough regarding his creative
block. Jay described a vision where he entered a space that
was very bright, very luminous, very beautiful and playful
and where he was dancing with giant gummy bears. He
recounted, I felt like a child, I felt like a happy, happy
child.Jay reported that during this vision:
The word Calliopejust popped into my mind. Calliope, C
A L L I O P E. I remember the impact of that word so vivid
that I actually wrote it down. And the next day when I was
reading my journal and I read that word, I looked it up and
it turns out that Calliope is the name of the ancient Greek
muse of creativity. I have it written down. Its true. Its
amazing ... what I interpreted from that was, the muse of
creativity was saying to me, listen, whenever you need me,
you know I'm inside of you. Just call me and I'll be there.So
that was the very rst real wowmoment that I had, you
know, it was a very clear answer to my intentions about the
creative ow in my life.
Jay also reported a significant experience where he met
with two deceased loved ones; his grandmother and an ex-
partner. Jay said his grandmother appeared to him as a
young woman, dressed in clothes from the early 1900s, and
he felt an overwhelming sense of love coming from her. She
communicated to him, we're all here. All of us are here and
we are all one. And none of us have ever gone because we're
all together.Jay also felt the presence of his ex-partner, who
was communicating to him, listen, its all ok.Jay described
this experience as, kind of like looking at the circle of life
and the message was: people come and people go and people
die and people are born, but our essence is ever, ever, ever,
ever present.This was a highly emotional experience for
Jay, and when he talked about it during the interview, he
began to cry.
Another salient incident involved an insight that was
delivered via an encounter with an oak tree. Jay gave an
The picture window was to my right and outside the picture
window was a garden and there was a huge oak tree. When
the tree saw me, she, and I say, she, because it was a
feminine energy, started dancing for me. [Then] she sud-
denly withered up and died. Literally withered up and
became dry, and all her leaves became dry and she died. But
then she would start coming back to life. And so she'd go
through this cycle of life and death, life and death for, I don't
know how long, but I kept staring at it. And the energy
coming from her was just absolute love and compassion and
comfort. And she was saying to me, listen this is a perfect
system that we're in. And all the chaos in our lives is okay,
because its part of this perfect system. So relax, everythings
going to be okay.
Jay described a change to his sense of self that was
persistent throughout the entire experience. He related, I
was just being, I wasn't a being, I was just there ... it was
like me at my absolute essence.He also reported feeling that
his experience was signicantly directed by the music, which
would carry him to different situations. He said, the musical
notes at one point became guides ... the music became a
physical guide that would take me towards somewhere.
In terms of after-effects, Jay described coming out of the
psilocybin experience with a lot of information, a lot of
knowledge, a lot of insights, a lot of peace.He started
writing his book the following week, and at the time of the
interview it was with a publisher. In the several months
following the retreat, Jay experienced two signicant losses
in his life; he split with his romantic partner, and his father
died. Jay credits the psilocybin experience with giving him
an increased ability to handle these challenges, as it just
gave me this feeling of serenity and acceptance and con-
dence in myself that weren't a constant before.He said the
psilocybin experience reminded him you have everything in
you that you need to deal with life. You have all those tools
already in you.Jay also revealed that the message he
received from his grandmother helped him deal with his
fathers passing, saying, now I know that theres another
realm out there ... and it might be within us ... it was very
comforting. I think I lost a lot of fear of death.There were
other changes to Jays spiritual life; after the retreat he
developed a regular meditation practice and reported that he
now connects to the sacred aspect of nature.He described
being a much more spiritually awareperson.
Finally, Jay expressed a desire to contribute to psyche-
delic research and to share his story with others. He said he
believes that the psilocybin experience is very important and
valuable, noting, I can't express enough how much grati-
tude I have and the respect I have for the substance itself and
Journal of Psychedelic Studies 3
Unauthenticated | Downloaded 04/17/21 01:12 AM UTC
for those who are managing it and using it properly in
responsible terms.
Ian was a male in his fifties, and was employed as the CEO
of a company. He was a self-described atheist and had
never taken a psychedelic before. After reading Michael
Pollans book How to Change Your Mind,Ian researched
psychedelics online and decided to attend a Synthesis
retreat. His main motivations for attending the retreat were
to explore consciousness, gain insight regarding his career
and to become calmer and more grounded.Ian said that
his psilocybin experience could be split into three parts:a
mysticalpart, a psychedelicpart, and a cognitive-psy-
chological part. These parts were delineated based on a
temporal structure, with the mystical part occurring during
the rst third of the experience, when the psilocybin effect
was at its peak. What Ian described as the typical psy-
chedelicpart of his experience involved traditional psy-
chedelic visual effectsand occurred about halfway through
his experience. One particularly salient effect he described
was being able to see the music in 3D,noting Itsbeyond
music]andlookatitfrom3608... in a way you could stop
time and look at music kind of stretched out as time.The
nal part of Ians experience was more cognitive and
involved relaxing without the blindfold and contem-
During his interview, Ian used the allegory of Platos
Cave to explain and make sense of his psilocybin experience,
which he described as being quite abstract yet incredibly
profound. One of the most signicant aspects of the expe-
rience was the presence of a light, which was always with
him. Ian said all the way through that trip, when I
encountered something difcult or scary, or something I
couldn't push through, I could always look up to see a light.
Most of the time, the light seemed to be partially obscured
by an opaque screen, however at a pivotal moment in the
experience what Ian described as the mysticalpart the
screen disappeared and the light broke through.When this
happened, Ian heard a female voice say you are not alone
and with this voice came a feeling of love that is every-
where,a sense of togetherness,and what he believes was
an ego dissolution experience. Ian described a very strong
experience of not being alone ... the certainty of not being
alone and this feeling of light and love that was shining
through everything ... everywhere.Ian described this
feeling of love as both owing through him and owing
from him, and said that he could send outthis love to
other people in the room. The emotional intensity of the
experience was so strong that Ians voice began to quaver
when he spoke of it during the interview, and he noted that
almost twelve months later, he still gets emotional when
talking about the experience.
Ian reported a number of significant life changes that
occurred after the psilocybin experience. He said the expe-
rience gave him a certainty of the importance of loveand
that since the experience he is closer to the world, the
people around me, more open, more warm, loving ... at
least my wife says so.He also described career changes,
including a signicant revision of his work priorities and an
increased sense of awareness regarding his interpersonal
relationships with others. Ian also reported signicant
changes to his health and wellbeing; in particular, he lost
20 kg in the year following the retreat. Weight loss was not a
specic intention going into the retreat, rather it was an
unexpected bonus.Ian attributed the weight loss to several
factors, including an absence of sugar cravings, a signicant
change to his sense of taste, so that everything I tasted was
much, much stronger,and a period of effortless change that
occurred in the month following the retreat. He reported
that after the retreat the ability to change was super easy.
Those rst three to four weeks, there was no effort at all.
Ian also believed that his previous unhealthy behaviors
were related to a feeling of existential darknessthat he had
felt since he was a teenager and that drove him to eat for
comfort. After the psilocybin experience, this feeling of
darkness disappeared:
obviously I've been eating less calories. So then you lose
weight. So thats some basic science there. But I think that
the most profound change from the experience is that since I
was a teenager, I think I've had some, I don't like to use the
word depressionbecause thats a clinical word and its not
a clinical depression. But okay, lets use the word just as a
description of a darknessthats always been there. And
that has disappeared. I'm much happier.
He also said that he now understands how his behaviors
and choices contributed to and influenced that sense of
darkness and how: I can foster that darkness and I can also
choose not to have it.
Almost twelve months later, Ian can still tap intoand
connect with the positive feeling associated with his psilocybin
experience, and he reported that this feeling is often connected
to sunlight, walking, running, or being outside. While he has
only discussed the mystical aspect of the experience with the
people closest to him, Ian has spoken to others about how the
experience in general changed his priorities and other aspects
of his life, noting I'm a strong believer in understanding Plato
in the sense that once you had seen the light in that cave, you
had an obligation to go out and talk about it somehow, in a
way to use that knowledge or that insight.While Ian said he
had no plan of becoming a preacher for psychedelics,he
believed that sharing his experience might help others in the
sense that his story could open that door for someone who
didn't know that that door was here.
Carol was a female in her fifties, who worked in marketing
and had never taken a psychedelic before. Carol read about
psychedelic retreats in a trend report and was gifted the
Synthesis retreat by a friend. Carols intentions for her psi-
locybin experience were to gain clarity regarding relation-
ships, self-love and anger. During the interview, Carol
described two particularly salient aspects of the experience.
4Journal of Psychedelic Studies
Unauthenticated | Downloaded 04/17/21 01:12 AM UTC
The rst involved a signicant change to her sense of self
that occurred early on; specically Carol described
becoming the room.Carol found it difcult to articulate
this aspect of the experience as she said it didn't make
senseto her. She explained, I had trouble understanding
that I had become the environment around meand
described not understanding the expansiveness.While
Carol said she wasn't sure if the experience was an ego
dissolution, she expressed, I wasn't me anymore.
The other significant part of Carols experience involved
a connection she made with one of the guides, Jasmine. At
one point during the session, Jasmine came over to comfort
Carol during a moment of distress. During this encounter,
Jasmines face changed so that she looked like Carols
adoptive mother. Carol had been adopted as a baby, and her
adoptive mother had died when Carol was fteen years old,
so this experience was very meaningful to her. Carol inter-
preted this visual effect not as a hallucination, but as a
revelation of truth.She related:
I mean, she really looked like my mom ... the rst thing I
noticed is her face just like uidly morphed ...And it was not
like, Oh my God, I'm being tricked.Its revealing: this is the
truth of that energy and that love.And then she aged rapidly.
I'm watching this happen. And then she just went into
decrepitness and decay but it was okay. Because I had the
experience that those things were all true at the same time.
Every moment shesalive,shes dead. Like, same thing.
The interaction with Jasmine also involved a boundary
dissolution experience, which Carol described as a physical
experience of oneness:
what I remember is that I was clenching her hand and that
sometimes I would maybe go on a little journey inside and I
would lose track of whose hand was whose, and where was
the line? So there was a physical experience of oneness. And
I would bring my other hand over to check because I had
lost the boundary. And I'm like, Oh, who is the boundary?
Oh, its me. Okay got it.
During the encounter with Jasmine, Carol had a number
of insights; an experience she described as feeling like
mainlining the universe.One key insight was the under-
standing that she was always taken care of, always loved and
never alone. Part of this insight involved the realization that
despite losing both her mothers, she had never been aban-
doned and actually had three mothers: her birth mother, her
adoptive mother, and the universe, who had always been
taking care of her. Other insights Carol reported were: we
are all connected/all one,”“intimacy is an act of surrender,
and allow just let things, situations, people, ow through
and around me.During the interview Carol said she has
since come to understand this part of the experience as a
rebirth,explaining, What I have come to know now is
that I had just been reborn.The day after the psilocybin
experience, Carol had a conversation with one of the guides,
David, who interpreted Carols interaction with Jasmine in
terms of disconnection and reconnection. Carol recounted,
he [David] was like, Birth is a disconnection.And mine
especially [being adopted] was a disconnection. You get cut
off from source and thrown into this world. And he was like,
What you had with Jasmine was reconnection.’”
Embodiment was a key theme that emerged from the
interview with Carol. She described lying in the fetal po-
sitionfor quite some time during the session (a position she
understood as being symbolic of her rebirth), and referred to
her experience of insight as a visceral understandingthat
could be felt in every layer and every cell.Additionally, for
weeks after the experience, Carol would occasionally get
little shakes,which she interpreted as a type of therapeutic
tremoring, like something working itself outof her body.
Although she cried throughout most of the session, Carol
described the overall nature of the experience as being
extremely positive, blissful and cathartic, like fty years of
therapy in 5 h.She expressed, there were things that were
healed, that therapy could never do.Twelve months later,
Carol can still reconnect to the psilocybin experience via
music and via a scented room spray which contains the same
fragrance that was used during the session; she said that
when she smells the fragrance, she can go back there.
Carol reported a number of enduring positive after-ef-
fects from the experience. She stated that she is now happier,
has a greater sense of ease around other people, experiences
less anger, and has more peace in her life. She said that the
experience, revealed to me in a very clear and powerful way,
ways for me to be more loving and accepting of myself.
When she shares her story with other people, Carol tells
them that psilocybin is not a hallucinogen, rather, it is a
its a revelation. Its a revelation-ogen. Because basically its
showing you, whats all true in there. And that too, I think is
one of the reasons that people are so clear about remem-
bering it. You're like, Oh no, this is how it is. This is the truth
of the fabric of the universe right now.You're not dreaming.
Carol also reported changes to her spiritual beliefs; she
now really believesin some spiritual and New Age ideas
that before seemed questionable to her. She also reported
reduced anxiety regarding death, noting death is nothing to
be afraid of.
Ben was a male in his forties, who worked in finance and
had never taken a psychedelic before. Ben attended the
retreat because he wanted to become more connected to
nature and peopleand to love more.In the years prior to
the retreat, Ben had suffered with some depression, and he
hoped the psilocybin experience might also lead to improved
mental health.
One of the most significant parts of Bens psilocybin
experience involved a period where he becamehis
In follow-up email correspondence, Carol emphasized that during the
experience Jasmine did not merely look like her mother, she was her
mother. Carol explained that this is the reason she referred to psilocybin
as a revelation-ogen:”“I saw the truth, the actual thing not the looked
Journal of Psychedelic Studies 5
Unauthenticated | Downloaded 04/17/21 01:12 AM UTC
pregnant wife. At some point during the experience, Ben felt
that he was no longer in the session room, but was back in
his bed at home. He noticed that he had developed a
stomach ache, and when he felt his stomach with his hands
he realized it had become a lot bigger as well.Ben then
described realizing that he had become his wife:
So there I was, holding this big stomach and at this point, I
wasn't actually lying in the [retreat] room. I was back in my
room upstairs at home. And I was in our bed. I was rubbing
my tummy and it was really hurting and I realized I was
pregnant. I'm lying in bed pregnant and I'm hurting and I'm
uncomfortable. And then I realized that I'm actually my wife
at this point. I'm now my wife and Iwasn't there.
Ben described the experience as feeling unquestionably
real, saying its not like you're imagining you're there, you
are literally there in your room at home.He said the
experience allowed him to understand life from his wifes
perspective, noting you become someone else and you're in
their shoes and you actually feel what they're feeling, it was
just incredibly powerful.The experience gave him a new
insight into his marriage, and as a result, he decided to
replace his lost wedding ring:
for about 10 years I hadn't worn a wedding ring. And I didn't
think that was that important ... and then from being in her
shoes, I actually realized there is a symbolism in it and it
does matter ... I bought a ring from a jewelry store in
Amsterdam the day after [the experience] because it just felt
like the right thing to do.
Another significant part of Bens experience involved a
period where he became an animal in a forest:
So theres quite an interesting period where I was in a
forest and I was a really small animal in the forest. I was
aware of the forest around me. And then I was becoming
smaller and smaller. So, I started off as just a small ani-
mal, but then became a little ant or something. And then
I was conscious, I was still getting smaller and smaller. So
While in the forest, Ben described experiencing other
people from his life as roots of a tree.He reported realizing
that he was just one tiny atomin a whole complex sys-
temand how there was no need to judge other people
because they're just roots of a tree. At the end of the day
they're just another organism in the whole scheme of
things.Bens psilocybin experience contained other similar
ecological themes. He related that at one point during the
experience he looked up at the moon outside and saw it
transform into the Earth: I was looking at the Earth. Not
crystal clear, but it was the Earth, spinning, with me on it
me, inconsequential yet a key component.Ben also
described a period where he felt that the psilocybin mush-
room was speaking to him:
There was a period where it felt like nothing had
happened for a long time. And I was starting to wonder
why not loads of stuff was happening. And then I got this
sort of feeling or message that its actually all right, that
you actually don't need that much. It was as if the
mushrooms were talking to me, and saying you are okay,
you know, everythings okay. You don't actually need
much from me... it was sort of telling me, you're
Ben said that while he didn't think he had a full mystical
experience,the experiences he did have denitely changed
my understanding of my place in the world and my human
life and my connectedness to others.He said he received
clarication regarding what it means to loveand that
during the experience of becoming his wife he almost fell in
love again.Ben said the experience has made him more
tolerant, accepting and empathetic towards others. Since the
retreat, depression hasn't been a problemand Ben attrib-
uted this improvement in his mental health to both the
psilocybin experience and subsequent lifestyle changes
including reduced alcohol intake, regular exercise, healthy
eating, and a consistent meditation practice. Another sig-
nicant after-effect that Ben reported was a new interest in
spirituality, consciousness, psychedelics and quantum
physics, which he said has been life-dening,explaining
its given me a passion and something to learn about and
drive towards.Ben also reported feeling more connected to
nature,and he cited examples such as experiencing more
beauty in the sound of birdsong, increased awe at sunrises,
less killing of insects, becoming more conscious of meat
consumption and an increased sense of connectedness to
natural cycles such as the moon cycle, tides and equinoxes.
While Ben struggled to reconcile some of the more spiritual
aspects of his psilocybin experience with his rational
worldview, he said the experience made him more curious
about spirituality and noted, I'm not worried about dying so
much.(Table 1)
Table 1. Participant demographics
Pseudonym Jay Ian Carol Ben
Age 50s 50s 50s 40s
Male Male Female Male
Ethnicity Caucasian Caucasian Caucasian Caucasian
None None None None
Education Master's
High High High High þ
Reason/s for
Retreat and
8 months
6Journal of Psychedelic Studies
Unauthenticated | Downloaded 04/17/21 01:12 AM UTC
The case studies in this article represent a sample of themes
that emerged during qualitative interviews. Each case study
provides a brief summary of the participants psilocybin
experience, but does not capture all the themes that emerged
for each participant; it only presents some of the highlights
from the experience. Despite the passage of time (the in-
terviews took place approximately eight to twelve months
after the retreat), all participants reported that the signicant
moments from their experience were still quite vivid. Salient
moments also appeared to be relatively easy to recall; for the
most part, participants spoke in the form of an extended
monologue, with very little prompting required from the
Based on these case studies, some general observations
can be made. Firstly, as noted by other researchers (e.g.,
Bogenschutz et al., 2018), the content of each psilocybin
experience was highly variable and each experience seemed
to uniquely match the perceived needs of the individual
participant. Sometimes the content of the experience related
directly to the participants specic intentions going into the
retreat, and at other times the content was meaningful but
unexpected. While the content of the experiences was
diverse, all participants reported typical psychedelic effects
including novel sensory-aesthetic effects, psychodynamic-
autobiographical experiences, symbolic-archetypal experi-
ences (particularly related to birth/death/rebirth and the
universal quality of love), heightened emotion, time distor-
tion, changes to sense of self, and mystical-type experiences
(e.g., Garcia-Romeu & Richards, 2018).
A key theme that emerged for all participants was the
experience of insight, both mystical and mundane. Partici-
pants framed their narrative accounts around key moments
of insight and described how these insights were related to
subsequent after-effects and significant changes in their
lives. Insights were primarily concerned with the theme of
connection: connection to self (e.g., increased self-confi-
dence, self-love, self-acceptance, creativity, and resourceful-
ness), connection to others (e.g., insights that involved
relationships with significant others, re-connecting with
deceased loved ones, connecting with other people present
during the session, and experiencing life from the perspec-
tive of others), and connection to a broader relational
ontology (e.g., understanding that one is connected to a
larger universe or ecological system). These findings are
consistent with studies that have found that psilocybin
promotes a generalized sense of connectednessto self,
others and the world (Carhart-Harris et al., 2018; Watts
et al., 2017). In these case studies, the concept of connection
or connectedness appeared as a common theme that
occurred throughout the general content of the experience,
but was most clearly articulated in relation to pivotal mo-
ments of insight.
Distortions to the subjective experience of self
(commonly termed ego dissolution) have been consis-
tently reported with high doses of psychedelics (e.g., Nour,
Evans, Nutt, & Carhart-Harris, 2016). Ego dissolution is
characterized by a reduction in the self-referential aware-
ness that denes normal waking consciousness, ultimately
disrupting self-world boundaries and increasing feelings of
unity with othersand ones surroundings(Mason et al.,
2020, p. 2003). All participants in this study reported sig-
nicant changes to self-other and self-world boundaries, a
reduced sense of personal identity/narrative self, and a
feeling of union with others and the world. Such ndings are
consistent with the phenomenon of ego dissolution. Inter-
estingly, while all participants in this study were familiar
with the term ego dissolution, some reported uncertainty
regarding the validity of their own self-dissolution experi-
ences. Specically, due to the inherent nonverbal nature of
such experiences, participants experienced difculty when
trying to articulate signicant changes to sense of self.
Additionally, participants all reported retaining a minimal
sense of a basic self (i.e., a sense of awarenessor of simply
being) throughout the experience, which made some
participants question whether what they had experienced
was truly ego dissolution.
Consistent with prior research on psilocybin occasioned
mystical experiences, participants in this study reported a
number of mystical-type experiences including noetic in-
sights, a feeling of transcending time and space, a sense of
passivity (feeling that they were not completely in control of
the experience), a sense of ineffability (difficulty describing
some aspects of the experience), and feelings of intercon-
nectedness and unity. Some scholars of mysticism (e.g.,
Hood, 1975; Stace, 1960) have argued that the unitive
experience(i.e., sense of onenessor unity) is a key
dening feature of the mystical experience. Further, it has
been posited that the phenomenology of the unitive expe-
rience overlaps with that of ego dissolution, and scholars
have found some support for this hypothesis (e.g., Nour
et al., 2016). Carhart-Harris et al. (2018) argue that
conceptually, the individual ego could be thought of as a
counter-forceto connectedness. Hence, the ego dissolution
experience or mystical unitive experience may be one
important factor that facilitates insights into connection.
The participants in this study also reported mystical-type
content that aligns more closely with animistic or shamanic
worldviews (e.g., ascribing a spirit or consciousness to a tree/
mushroom; experiencing oneself as an animal) and with
other anomalous experiences such as near death experiences
(e.g., meeting with deceased loved ones). Such experiences
might also play a significant role in facilitating or potenti-
ating key insights regarding connection to others and to a
broader relational ontology. Interestingly, only two partici-
pants mentioned a behavioral manifestation of nature-
relatedness as an after-effect (i.e., Jay described connecting
to the sacred aspect of natureand Ben noted a number of
changes), however it is possible that this theme will emerge
with a larger sample size or with direct questioning. For
example, in follow-up email correspondence, Carol reported
that she had experienced increased nature-relatedness and
that part of her integration practice involves bringing a
fragrant botanical into my life every day in sight and
Journal of Psychedelic Studies 7
Unauthenticated | Downloaded 04/17/21 01:12 AM UTC
smell and touch. When I do that its like a little jolt of this
experience. Its been one of the most powerful pieces of my
integration practices.She explained that this practice allows
her to retain a connection with her guide, Jasmine.
Embodiment was also a key theme. Participants reported
experiences such as inhabiting the body of another, insights
that were felt viscerally, and after-effects that involved
changes to the physical body. All participants said the psilo-
cybin experience was highly emotional, and all experienced
periods of heightened emotion when relaying the experience
during the interview. A common bodily response, both during
the psilocybin experience and during the interview, was
crying. However, while some participants recounted moments
of confusion or transient distress, all said that the overall
emotional tone of the psilocybin experience was over-
whelmingly positive. Hence, the crying seemed to be related
to a process of catharsis rather than sadness. Some partici-
pants mentioned being able to tap intoor reconnect with
the powerful positive feelings associated with their experience,
and that this was achieved via bodily sensations (e.g., sense of
smell) or through physical activity (e.g., walking or running).
Recently there has been a growing recognition that the mind-
body relationship is more profound than was initially
thought, and research in the area of embodied cognitionhas
demonstrated that the mind, rather than being an abstract
and isolated entity, is grounded in embodiment (e.g., Varela,
Thompson, & Rosch, 2016). In their study of psilocybin-
assisted psychotherapy for cancer patients, Belser et al. (2017)
also found that embodiment was a critical feature of psilo-
cybin experiences. Similarly, in their study of psilocybin for
treatment-resistant depression, Watts et al. (2017) reported
embodiment of emotions as a theme. Embodiment is
currently an understudied area in psychedelic research, and
future studies might consider how psilocybin-induced novel
bodily effects mediate the experience of insight.
In this study, no serious adverse events were reported.
One participant mentioned a brief period of transient
distress, which was then transformed into a cathartic
breakthrough experience. This nding is consistent with the
results of a recent survey study which found that 84% of
psilocybin users who experienced a bad tripultimately
beneted from the experience (Carbonaro et al., 2016).
Similarly, Belser et al. (2017, p. 379) suggest that periods of
transient distress may function as a necessary turning
pointin an unfolding process, as feelings of fear, panic, and
anxiety transmute into feelings of love, joy, and forgiveness.
The results from these case studies suggest there are
benefits for healthy individuals taking a high dose of psilo-
cybin. Participants reported a range of positive after-effects,
including psychological changes (e.g., improved mood,
increased resilience, reductions in anxiety and anger, feeling
more at peace, being kinder to oneself), interpersonal
changes (e.g., feeling more loving, tolerant, accepting and
empathetic towards others; having an increased sense of
awareness regarding others), and changes to health and
wellbeing (e.g., weight loss, exercise and dietary changes,
reduced alcohol consumption, development of new in-
terests). These after-effects were enduring and had persisted
for up to twelve months, a finding which is consistent with
other studies that have demonstrated that psilocybin has
long-term positive after-effects (e.g., Barrett et al., 2020;
Doblin, 1991). The three participants in this study who
identied as spiritual but not religious(SBNR) also re-
ported changes to their spiritual lives. These participants
reported changes to, or reinforcement of, their spiritual
beliefs, changes to spiritual practices (e.g., beginning and/or
maintaining a regular meditation practice), an increased
interest in spirituality, and becoming more spiritual.All
three SBNR participants reported a decreased fear of death, a
nding that is consistent with several survey studies of
psychedelic experiences (e.g., Davis et al. 2020; Grifths
et al., 2019; Yaden et al., 2017). Finally, an unexpected
nding was that during the interview two participants (Jay
and Ian) spontaneously reported a desire to share the story
of their psychedelic experience in the hope that it might
benet others.
Future research might investigate whether
this is a reliable and robust nding, and if so, whether there
is a link between psilocybin use and altruism.
In this article, case studies have been utilized to provide a
detailed and in-depth report of a single psilocybin experience.
However, it is important to point out that a key disadvantage
of the case study approach is the potential for both researcher
bias and lack of representativeness. For example, Guba and
Lincoln (1981, p. 378) argue: An unethical case writer could
so select from among available data that virtually anything he
[sic] wished could be illustrated." While this study has
attempted to minimize bias by selecting four case studies that
the researcher believes adequately represent themes that were
common to the entire data set, it must be noted that the
inherent variability of the psilocybin experience means that it
is difcult to make generalizations based on a small sub-
sample. In addition, there are sometimes outliers (e.g., expe-
riences that are very abstract and have little to no narrative
content). Hence, future research will involve a thematic
analysis of the entire data set, which should contribute to a
more comprehensive narrative.
Further, future analysis will take into account the impact
of set and setting, which has been shown to play an important
role in the psychedelic experience (e.g., Hartogsohn, 2017).
Synthesis retreats involve extensive preparation (including
guidance from facilitators before the retreat, the setting of
intentions, suggested daily practices leading up to the retreat
and suggested pre-reading), facilitator support during the
experience, and post-experience integration (including inte-
gration workshops during the retreat, one-on-one integration
coaching with facilitators, an additional group call after
returning home, and the option of further integration
coaching sessions after the retreat). The Synthesis retreat
This was the case for both the sub-sample and the complete data set.
It should also be noted that all four case study participants, in their de-
brieng conversations with the researcher, expressed their desire to
contribute to psilocybin research in the hope that it might benet others.
8Journal of Psychedelic Studies
Unauthenticated | Downloaded 04/17/21 01:12 AM UTC
program is explicitly aimed at personal transformation and
includes a number of supportive practices that may potentiate
the psychedelic experience and direct it towards this aim.
These practices include group workshops, meditation, self-
reective journaling and breathwork. While an in-depth
analysis of how these factors might shape participantsex-
periences is beyond the scope of this article, future research
will consider the inuence of set and setting.
Finally, this study is unique in that it might be the first
study to examine participant experiences where high dose
psilocybin was consumed in the form of whole truffles. A
recent study by Mason et al. (2019) utilized whole trufes
consumed in a retreat setting when examining the sub-acute
effects of psilocybin on creative thinking, empathy, and well-
being. However, the Mason et al. (2019) study used a dose of
15 g, while in the present study the dose range was 3080 g.
The study of the effects of psilocybin when consumed in
whole trufe form might be an important avenue for future
research. Currently, clinical studies of psilocybin use syn-
thetic psilocybin; however, there is evidence to suggest that
psilocybin mushrooms contain other compounds which lead
to an entourage effect(a synergistic interaction between
two or more different molecules when those molecules are
co-administered) and that this effect could inuence both
the nature of the psychedelic experience and its associated
behavioral outcomes (e.g., Gartz, 1994; Matsushima et al.,
2009; Zhuk et al., 2015). While the results of the present
study were comparable to results obtained in studies using
synthetic psilocybin, it is possible that future analysis of a
larger data set might reveal subtle differences between
trufes and synthetic psilocybin.
In conclusion, the experiential themes that emerged from
these case studies closely match themes that have been
identified in previous studies of psilocybin, including vari-
ability of the experience, the presence of mystical-type fea-
tures, significant changes to subjective sense of self (i.e., ego
dissolution), and insights related to a generalized sense of
connection (to self, others, and to a broader relational
ontology). Additionally, the theme of embodiment and its
relationship to insight is an understudied area in psychedelic
research and warrants further investigation. Finally, this
study provides preliminary evidence to suggest that in a
well-controlled and supportive retreat setting, a high dose of
psilocybin can lead to enduring positive after-effects in
healthy individuals. In such a setting, psilocybin appears to
be safe and well tolerated. While further interviews with
additional participants should provide more insight into key
phenomenological themes, the case studies presented here
provide preliminary evidence that complements existing
studies of psilocybin and that could be used to generate new
hypotheses for future research.
This study was approved by and carried out in accordance
with the recommendations of The University of Sydney
Human Research Ethics Committee. Participation was
voluntary and no incentive to participate was provided. All
participants gave their written informed consent to partici-
pate and were told that they could withdraw from the study
at any time.
Barrett, F. S., Doss, M. K., Sepeda, N. D., et al. (2020). Emotions
and brain function are altered up to one month after a single
high dose of psilocybin. Scientic Reports,10:2214, 114.
Belser, A. B., Agin-Liebes, G., Swift, T. C., et al. (2017). Patient
experiences of psilocybin-assisted psychotherapy: An interpre-
tive phenomenological analysis. Journal of Humanistic Psy-
chology,57(4), 354388.
Bogenschutz, M. P., Forechimes, A. A., Pommy, J. A., et al. (2015).
Psilocybin-assisted treatment for alcohol dependence: A proof-
of-concept study. Journal of Psychopharmacology,29(3), 289
Bogenschutz, M. P., Podrebarac, S. K., Duane, J. H., et al. (2018).
Clinical interpretations of patient experience in a trial of psi-
locybin-assisted psychotherapy for alcohol use disorder. Fron-
tiers in Pharmacology,9:100,17.
Breeksema, J. J, et al. (2020). Psychedelic treatments for psychiatric
disorders: A systematic review and thematic Synthesis of pa-
tient experiences in qualitative studies. CNS Drugs,34(9), 925
Survey study of challenging experiences after ingesting psi-
locybin mushrooms: Acute and enduring positive and nega-
tive consequences. Journal of Psychopharmacology,30(12),
Carhart-Harris, R. L., Erritzoe, D., Haijen, E., et al. (2018). Psyche-
delics and connectedness. Psychopharmacology (Berl),235(2),
Carhart-Harris, R. L., & Friston, K. J. (2019). REBUS and the
anarchic brain: Toward a unied model of the brain action of
psychedelics. Pharmacological Reviews,71(3), 316344.
Carhart-Harris, R. L., & Nutt, D. J. (2017). Serotonin and brain
function: A tale of two receptors. Journal of Psychopharmacol-
ogy,31(9), 10911120.
Davis, A. K., Clifton, J. M., Weaver, E. G., et al. (2020). Survey
of entity encounter experiences occasioned by inhaled
N,N-dimethyltryptamine: phenomenology, interpretation, and
enduring effects. Journal of Psychopharmacology,34(9),
Doblin, R. (1991). Pahnkesgood friday experiment: A long-term
follow-up and methodological critique. Journal of Trans-
personal Psychology,23(1), 128.
Garcia-Romeu, A., Grifths, R. R., & Johnson, M. W. (2014).
Psilocybin-occasioned mystical experiences in the treatment
of tobacco addiction. Current Drug Abuse Reviews,7(3), 157
Garcia-Romeu, A., & Richards, W. A. (2018). Current perspectives
on psychedelic therapy: Use of serotonergic hallucinogens in
Journal of Psychedelic Studies 9
Unauthenticated | Downloaded 04/17/21 01:12 AM UTC
clinical interventions. International Review of Psychiatry,30(4),
Gartz, J. (1994). Extraction and analysis of indole derivatives from
fungal biomass. Journal of Basic Microbiology,34(1), 1722.
Grifths, R. R., et al. (2018). Psilocybin-occasioned mystical-type
experience in combination with meditation and other spiri-
tual practices produces enduring positive changes in psy-
chological functioning and in trait measures of prosocial
attitudes and behaviors. Journal of Psychopharmacology,
32(1), 4969.
Grifths, R. R., Hurwitz, E. S., Davis, A. K., et al. (2019). Survey of
subjective God encounter experiences:Comparisons among
naturally occurring experiences and those occasioned by the
classic psychedelics psilocybin, LSD, ayahuasca, or DMT. PloS
Grifths, R. R., Johnson, M. W., Carducci, M. A. et al. (2016).
Psilocybin produces substantial and sustained decreases in
depression and anxiety in patients with life-threatening cancer:
A randomized double-blind trial. Journal of Psychopharmacol-
ogy,30(12), 11811197.
Guba, E., & Lincoln, Y. (1981). Effective evaluation. San Francisco,
CA: Jossey-Bass.
Hartogsohn, I. (2017). Constructing drug effects: a history of set
and setting. Drug Science, Policy and Law,3(0), 117.
Hartogsohn, I. (2018). The meaning-enhancing properties of psy-
chedelics and their mediator role in psychedelic therapy,
spirituality, and creativity. Frontiers in Neuroscience,12:129,
Hood, R. (1975). The construction and preliminary validation of a
measure of reported mystical experience. Journal for the Sci-
entic Study of Religion,14(1), 2941.
James, E., Robertshaw, T. L., Hoskins, M., & Sessa, B. (2020).
Psilocybin occasioned mystical-type experiences. Human Psy-
chopharmacology: Clinical and Experimental,35(5), 18.
Johnson, M. W., Garcia-Romeu, A., Cosimano, M. P., & Grifths,
R. R. (2014). Pilot study of the 5-HT2AR agonist psilocybin in
the treatment of tobacco addiction. Journal of Psychopharma-
cology,28(11), 983992.
Johnson, M. W., Garcia-Romeu, A., & Grifths, R. R. (2017). Long-
term follow-up of psilocybin-facilitated smoking cessation. The
American Journal of Drug and Alcohol Abuse,43(1), 5560.
Lyons, T., & Carhart-Harris, R. L. (2018). Increased nature related-
ness and decreased authoritarian political views after psilocybin
for treatment-resistant depression. Journal of Psychopharma-
cology,32(7), 811819.
Madsen, M. K., Fisher, P. M., Stenbæk, D. S., et al. (2020). A single
psilocybin dose is associated with long-term increased mind-
fulness, preceded by a proportional change in neocortical 5-
HT2A receptor binding. European Neuropsychopharmacology,
assisted psychotherapy. Frontiers in Pharmacology,9:256,1
Mason, N. L., Kuypers, K. P. C, M
uller, F., et al. (2020). Me, myself,
bye: Regional alterations in glutamate and the experience of ego
dissolution with psilocybin. Neuropsychopharmacology,45(12),
Mason, N. L., Mischler, E., Uthaug, M. V., et al. (2019). Sub-acute
effects of psilocybin on empathy, creative thinking, and sub-
jective well-being. Journal of Psychoactive Drugs,51(2), 123
Matsushima, Y., et al. (2009). Effects of psilocybe argentipes on
marble-burying behavior in mice. Bioscience, Biotechnology,
and Biochemistry,73(8), 18661868.
Minichiello, V., Aroni, R., & Hays, T. (2008). In-depth inter-
viewing (3rd ed.). Melbourne, VIC: Pearson Education
Moreno, F. A., Wiegand, C. B., Taitano, E. K., & Delgado, P. L.
(2006). Safety, tolerability, and efcacy of psilocybin in 9 pa-
tients with obsessive compulsive disorder. Journal of Clinical
Psychiatry,67(11), 17351740.
Nielson, E. M., May, D. G., Forcehimes, A. A., et al. (2018). The
psychedelic debrieng in alcohol dependence treatment: Illus-
trating key change phenomena through qualitative content
analysis of clinical sessions. Frontiers in Pharmacology,9:132,
Noorani, T., Garcia-Romeu, A., Swift, T. C., et al. (2018). Psyche-
delic therapy for smoking cessation: Qualitative analysis of
participant accounts. Journal of Psychopharmacology,32(7),
Nour, M. M., Evans, L., Nutt, D., & Carhart-Harris, R. L. (2016).
Ego-dissolution and psychedelics: Validation of the ego-disso-
lution inventory (EDI). Frontiers in Human Neuroscience,
Roseman, L., Nutt, D. J., & Carhart-Harris, R. (2018). Quality of
acute psychedelic experience predicts therapeutic efcacy of
psilocybin for treatment-resistant depression. Frontiers in
Ross, S., Bossis, A., Guss, J. et al. (2016). Rapid and sustained
symptom reduction following psilocybin treatment for anxiety
and depression in patients with life-threatening cancer: A
randomized controlled trial. Journal of Psychopharmacology,
30(12), 11651180.
Russ, S. L., Carhart-Harris, R. L., Maruyama, G., & Elliott, M. S.
(2019). Replication and extension of a model predicting response
to psilocybin. Psychopharmacology,236(11), 32213230.
Simons, H. (2009). Case study research in practice. Los Angeles,
Stace, W. T. (1960). Mysticism and philosophy. London, UK: Macmillan
and Co. Ltd.
Swift, T. C., Belser, A. B., Agin-Liebes, G., et al. (2017). Cancer at
the dinner table: Experiences of psilocybin-assisted psycho-
therapy for the treatment of cancer-related distress. Journal of
Humanistic Psychology,57(5), 488519.
Turton, S., Nutt, D. J., & Carhart-Harris, R. L. (2014). A qualitative
report on the subjective experience of intravenous psilocybin
administered in an fMRI environment. Current Drug Abuse
Reviews,7, 117127.
Varela, F. J., Thompson, E., & Rosch, E. (2016). The embodied mind
(Revised Edition). Cambridge, MA and London, England: The
MIT Press.
10 Journal of Psychedelic Studies
Unauthenticated | Downloaded 04/17/21 01:12 AM UTC
Watts, R., Day, C., Krzanowski, J., Nutt, D., & Carhart-Harris, R.
(2017). Patientsaccounts of increased connectednessand
acceptanceafter psilocybin for treatment-resistant depres-
sion. Journal of Humanistic Psychology,57(5), 520564.
Yaden, D. B., LeNguyen, K. D., Kern M. L., et al. (2017). Of roots and
fruits: A comparison of psychedelic and nonpsychedelic mystical
experiences. Journal of Humanistic Psychology,57(4), 338353.
Zamaria, J. A. (2016). A phenomenological examination of psilo-
cybin and its positive and persisting after-effects. Neuro-
Quantology,14(2), 285296.
Zhuk, O., Jasicka-Misiak, I., Poliwoda, A., et al. (2015). Research on
acute toxicity and the behavioral effects of methanolic extract
from psilocybin mushrooms and psilocin in mice. Toxins,7(4),
Open Access. This is an open-access article distributed under the terms of the Creative Commons Attribution-NonCommercial 4.0 International License (https://, which permits unrestricted use, distribution, and reproduction in any medium for non-commercial purposes, provided the
original author and source are credited, a link to the CC License is provided, and changes if any are indicated.
Journal of Psychedelic Studies 11
Unauthenticated | Downloaded 04/17/21 01:12 AM UTC
... Previous research has highlighted that qualitative methods offer an in-depth understanding of patients' subjective experiences (Meikle et al., 2020) and the information can supplement the data obtained through quantitative measures (Watts, 2020). Therefore, by exploring patients' experiences, researchers could improve their understanding of the underlying psychological mechanisms and processes of PAT to ensure more effective treatment (Lutkajtis, 2021). Similarly, quantitative measures might not capture the full extent of the highly personalised psilocybin-induced experience. ...
... Research conducted in various settings using qualitative and/or quantitative methodologies, recognises the value of a facilitator (Breeksema et al., 2020;Wheeler & Dyer, 2020). In this context, the beneficial outcome of psilocybin is dependent on a compassionate environment where administration is guided by a healthcare professional and supplemented with psychotherapy (Al-Nagger et al., 2021;Breeksema et al., 2020;Lutkajtis, 2021). Conversely, Bienemann et al. (2020) noted that negative outcomes can occur when using psilocybin recreationally, specifically when ingesting multiple doses of psilocybin in the same session or combining it with other substances. ...
Full-text available
There has been a surge in research on Psilocybin-Assisted Therapy (PAT) over the past three decades. PAT has yielded positive results across clinical trials and demonstrated efficacy in treating various mental disorders. However, limited qualitative research exists that explores peoples’ experiences of PAT. This study aims to review the current literature on the experiences of individuals that have participated in PAT, as well as individuals that have facilitated PAT. This study aims to increase our understanding of PAT to guide and improve therapeutic effectiveness. A scoping review was conducted from English language studies published in peer-reviewed journals. Searches were conducted from PsycInfo, CINAHL, PubMed, Web of Science, and Cochrane Library databases. Inclusion criteria were qualitative studies involving PAT that were conducted between January 1990 and December 2022; articles published in peer-reviewed journals; and psychedelic practitioners’ experiences of facilitating PAT. In total, 13 articles were extracted to be included in the review. Articles were published between 2017 and 2021, and were divided into (1) Participant Studies (10) and (2) Facilitator Studies (3). Six themes were identified: the influence of set and setting; PAT was personalised and meaningful; PAT can be highly emotive; transcendental experiences; reduction of symptoms and long-lasting changes; and boundaries and responsibility. The literature revealed numerous interrelated therapeutic elements that may have contributed to a meaningful experience during PAT. This may play a role in attaining long-lasting positive therapeutic outcomes. The studies were varied and highlighted the usefulness of further exploring PAT.
... Psilocybin is a nonselective serotonin receptor agonist that can alter individuals' perceptions, moods, and cognitive processes (Nichols and Barker 2016). Termed a "classic psychedelic", psilocybin has been found to be associated with positive, long-term effects on healthy individuals' mindfulness (Madsen et al. 2020;McCulloch et al. 2021), connectedness (Lutkajtis 2021;Studerus et al. 2010), and ties to nature (Kettner et al. 2019). Although this research is in a nascent stage, each of these long-term effects offers a unique mechanism of action by which psilocybin could potentially decrease individuals' willingness to allocate their finite time to their employer. ...
Despite the recent and sharp rise in psychedelic research, few studies have investigated how classic psychedelic use relates to employees' work-related outcomes. This is surprising given that the increased use, decriminalization, and legalization of classic psychedelics in the United States (U.S.) has the potential to impact both employees and their organizations. Addressing this gap, the current study explores how employees' lifetime psilocybin use relates to the amount of overtime they work, thereby offering insight into what current trends in psilocybin use could mean for businesses. Using pooled, cross-sectional data from the National Survey on Drug Use and Health (2002-2014) on 217,963 adults employed in the U.S. full-time, this study tests whether lifetime psilocybin use is associated with employees' number of overtime hours worked in the past week. After adjusting for sociodemographics and other substance use, a significant negative association is found between employees' lifetime psilocybin use and the amount of overtime they reported working. Specifically, the findings suggest that lifetime psilocybin use in the U.S. full-time working population is associated with an estimated 44,348,400 fewer overtime hours worked per year and may help explain recent findings linking employees' lifetime psilocybin use to a reduction in sick leave taken.
... Numerous empirical studies have demonstrated that classic psychedelics, including lysergic acid diethylamide (LSD), psilocybin (magic mushrooms), and mescaline (peyote), are safe and of high therapeutic use for treating mental health disorders such as depression and anxiety (for reviews see Aday, Mitzkovitz, Bloesch, Davoli, & Davis, 2020;Carhart-Harris & Goodwin, 2017;Chi & Gold, 2020;Elsey, 2017). These serotonin receptor agonists, which can alter individuals' perceptions, moods, and cognitive processes (Nichols, 2016), are believed to help individuals process difficult feelings like anxiety and distress by increasing their feelings of connectiveness with the world and others (Lutkajtis, 2021;Studerus, Kometer, Hasler, & Vollenweider, 2010) and decreasing their fear of death (Gasser, Kirchner, & Passie, 2015;Sweeney et al., 2022). Although clinical studies into the effects of these psychoactive substances are still quite new, they have been used for healing purposes for millennia (Strassman, 1995). ...
Full-text available
Background Despite recent research linking lifetime classic psychedelic use to positive mental health outcomes, little work has explored the role played by classic psychedelics in healthy users' ability to cope with ordinary, yet stressful, life situations. Aims This study begins to fill this gap by exploring whether lifetime classic psychedelic use is associated with attenuated or exacerbated psychological distress in unemployed job seekers. Methods Drawing on openly-available data from the National Survey on Drug Use and Health (2013–2019) on 208,136 adults in the United States, this study tests whether lifetime classic psychedelic use interacts with employment status to predict differences in respondents' psychological distress experienced in the last 30 days. Results After adjusting for sociodemographics, health factors, and other substance use, unemployed job seekers with lifetime classic psychedelic use are found to report greater psychological distress relative to unemployed job seekers without lifetime psychedelic use. No differences in psychological distress based on lifetime classic psychedelic use were found in employed individuals. Conclusion This study suggests that lifetime classic psychedelic use (of indoleamines specifically) may exacerbate stressful phases of life and provides context to previous studies linking lifetime classic psychedelic use to predominantly positive mental health outcomes in healthy populations. Declaration of interest/funding This research received no specific grant from any funding agency in the public, commercial, or not-for-profit sectors. Furthermore, the author declares that there is no conflict of interest.
... In particular, studies suggest that psychedelics may be an effective treatment for a variety of clinical issues, including treatment-resistant depression , cancer-related distress Ross et al., 2016), obsessive compulsive disorder (Moreno et al., 2006), substance use disorders (Bogenschutz et al., 2015(Bogenschutz et al., , 2018Johnson, Garcia-Romeu, & Griffiths, 2017), eating disorders (Spriggs, Kettner, & Carhart-Harris, 2020), and neurodegenerative disorders (Saeger & Olson, 2021). Psychedelics have also been posited to promote healthy lifestyle changes (Lutkajtis, 2021;Madsen et al., 2020;Teixeira et al., 2022), increase nature-relatedness (Lyons & Carhart-Harris, 2018) and foster environmental virtues (Kirkham & Letheby, 2022). Additionally, Gandy, Bonnelle, Jacobs, and Luke (2022) argue that psychedelics might act as potential catalysts of scientific creativity and insight. ...
Full-text available
This article reports on integration challenges that were experienced by nine individuals who attended a three-day legal psilocybin truffle retreat in the Netherlands. The study employed a qualitative phenomenological approach, using semi-structured interviews to gain an understanding of participants' ( n = 30) psilocybin experiences and their after-effects. While the study did not actively seek to measure integration issues or unexpected side effects, nine out of thirty participants (30%) spontaneously reported a post-experience integration challenge. These challenges included: mood fluctuations, ‘post-ecstatic blues’, disconnection from community, re-experiencing symptoms, spiritual bypass and perceived lack of support. Integration challenges were transient; they occurred immediately after the psilocybin experience (once the main psychedelic effects had worn off) and in the days and weeks following the retreat, and resolved with time. Integration challenges were also correlated with positive after-effects including long-term remission of significant health conditions. The experiences related in this article align with existing literature that describes the ‘spiritual emergency’ phenomenon; that is, the potential challenges that can arise after ecstatic experiences and how these challenges may be integral to the transformative potential of such experiences. We discuss the implications for psychedelic integration and harm reduction practices and for future psychedelic research.
Full-text available
Recently there has been a surge of renewed interest in the psychedelic compound psilocybin. In particular, psilocybin is being studied in clinical settings as a potential breakthrough treatment for depression. Alongside this growing therapeutic interest, there has been a rise in the religious use of psilocybin, as evidenced by the creation of a number of psilocybin mushroom churches in the United States. While the dominant popular discourse surrounding psilocybin is currently clinical, psilocybin churches offer an alternative form of meaning making regarding the psychedelic experience. Specifically, this article argues that psilocybin churches enable their followers to participate in a dynamic social process of sacred sensemaking, whereby psilocybin mushrooms are considered to be a sacrament, church members follow a ritual-based psychopharmacological practice, and the psychedelic experience is interpreted in terms of a direct encounter with the divine. Different psilocybin churches have unique approaches, ritual practices and cosmologies, nonetheless this article suggests that they may be united by this common process of 'sacred sensemaking'.
Full-text available
Introduction Interest in the use of psychedelic substances for the treatment of mental disorders is increasing. Processes that may affect therapeutic change are not yet fully understood. Qualitative research methods are increasingly used to examine patient accounts; however, currently, no systematic review exists that synthesizes these findings in relation to the use of psychedelics for the treatment of mental disorders. Objective To provide an overview of salient themes in patient experiences of psychedelic treatments for mental disorders, presenting both common and diverging elements in patients’ accounts, and elucidating how these affect the treatment process. Methods We systematically searched the PubMed, MEDLINE, PsycINFO, and Embase databases for English-language qualitative literature without time limitations. Inclusion criteria were qualitative research design; peer-reviewed studies; based on verbalized patient utterances; and a level of abstraction or analysis of the results. Thematic synthesis was used to analyze and synthesize results across studies. A critical appraisal of study quality and methodological rigor was conducted using the Critical Appraisal Skills Programme (CASP). Results Fifteen research articles, comprising 178 patient experiences, were included. Studies exhibited a broad heterogeneity in terms of substance, mental disorder, treatment context, and qualitative methodology. Substances included psilocybin, lysergic acid diethylamide (LSD), ibogaine, ayahuasca, ketamine and 3,4-methylenedioxymethamphetamine (MDMA). Disorders included anxiety, depression, eating disorders, post-traumatic stress disorder, and substance use disorders. While the included compounds were heterogeneous in pharmacology and treatment contexts, patients reported largely comparable experiences across disorders, which included phenomenological analogous effects, perspectives on the intervention, therapeutic processes and treatment outcomes. Comparable therapeutic processes included insights, altered self-perception, increased connectedness, transcendental experiences, and an expanded emotional spectrum, which patients reported contributed to clinically and personally relevant responses. Conclusions This review demonstrates how qualitative research of psychedelic treatments can contribute to distinguishing specific features of specific substances, and carry otherwise undiscovered implications for the treatment of specific psychiatric disorders.
Full-text available
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 improvements in positive mental outlook and attitudes. This article aims to provide an overview 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 differences 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.
Full-text available
There is growing interest in the therapeutic utility of psychedelic substances, like psilocybin, for disorders characterized by distortions of the self-experience, like depression. Accumulating preclinical evidence emphasizes the role of the glutamate system in the acute action of the drug on brain and behavior; however this has never been tested in humans. Following a double-blind, placebo-controlled, parallel group design, we utilized an ultra-high field multimodal brain imaging approach and demonstrated that psilocybin (0.17 mg/kg) induced region-dependent alterations in glutamate, which predicted distortions in the subjective experience of one’s self (ego dissolution). Whereas higher levels of medial prefrontal cortical glutamate were associated with negatively experienced ego dissolution, lower levels in hippocampal glutamate were associated with positively experienced ego dissolution. Such findings provide further insights into the underlying neurobiological mechanisms of the psychedelic, as well as the baseline, state. Importantly, they may also provide a neurochemical basis for therapeutic effects as witnessed in ongoing clinical trials.
Full-text available
Background Experiences of having an encounter with seemingly autonomous entities are sometimes reported after inhaling N,N-dimethyltryptamine. Aim The study characterized the subjective phenomena, interpretation, and persisting changes that people attribute to N,N-dimethyltryptamine-occasioned entity encounter experiences. Methods Two thousand, five hundred and sixty-one individuals (mean age 32 years; 77% male) completed an online survey about their single most memorable entity encounter after taking N,N-dimethyltryptamine. Results Respondents reported the primary senses involved in the encounter were visual and extrasensory (e.g. telepathic). The most common descriptive labels for the entity were being, guide, spirit, alien, and helper. Although 41% of respondents reported fear during the encounter, the most prominent emotions both in the respondent and attributed to the entity were love, kindness, and joy. Most respondents endorsed that the entity had the attributes of being conscious, intelligent, and benevolent, existed in some real but different dimension of reality, and continued to exist after the encounter. Respondents endorsed receiving a message (69%) or a prediction about the future (19%) from the experience. More than half of those who identified as atheist before the experience no longer identified as atheist afterwards. The experiences were rated as among the most meaningful, spiritual, and psychologically insightful lifetime experiences, with persisting positive changes in life satisfaction, purpose, and meaning attributed to the experiences. Conclusion N,N-dimethyltryptamine-occasioned entity encounter experiences have many similarities to non-drug entity encounter experiences such as those described in religious, alien abduction, and near-death contexts. Aspects of the experience and its interpretation produced profound and enduring ontological changes in worldview.
Full-text available
Psilocybin is a classic psychedelic compound that may have efficacy for the treatment of mood and substance use disorders. Acute psilocybin effects include reduced negative mood, increased positive mood, and reduced amygdala response to negative affective stimuli. However, no study has investigated the long-term, enduring impact of psilocybin on negative affect and associated brain function. Twelve healthy volunteers (7F/5M) completed an open-label pilot study including assessments 1-day before, 1-week after, and 1-month after receiving a 25 mg/70 kg dose of psilocybin to test the hypothesis that psilocybin administration leads to enduring changes in affect and neural correlates of affect. One-week post-psilocybin, negative affect and amygdala response to facial affect stimuli were reduced, whereas positive affect and dorsal lateral prefrontal and medial orbitofrontal cortex responses to emotionally-conflicting stimuli were increased. One-month post-psilocybin, negative affective and amygdala response to facial affect stimuli returned to baseline levels while positive affect remained elevated, and trait anxiety was reduced. Finally, the number of significant resting-state functional connections across the brain increased from baseline to 1-week and 1-month post-psilocybin. These preliminary findings suggest that psilocybin may increase emotional and brain plasticity, and the reported findings support the hypothesis that negative affect may be a therapeutic target for psilocybin.
Full-text available
This paper formulates the action of psychedelics by integrating the free-energy principle and entropic brain hypothesis. We call this formulation relaxed beliefs under psychedelics (REBUS) and the anarchic brain, founded on the principle that—via their entropic effect on spontaneous cortical activity—psychedelics work to relax the precision of high-level priors or beliefs, thereby liberating bottom-up information flow, particularly via intrinsic sources such as the limbic system. We assemble evidence for this model and show how it can explain a broad range of phenomena associated with the psychedelic experience. With regard to their potential therapeutic use, we propose that psychedelics work to relax the precision weighting of pathologically overweighted priors underpinning various expressions of mental illness. We propose that this process entails an increased sensitization of high-level priors to bottom-up signaling (stemming from intrinsic sources), and that this heightened sensitivity enables the potential revision and deweighting of overweighted priors. We end by discussing further implications of the model, such as that psychedelics can bring about the revision of other heavily weighted high-level priors, not directly related to mental health, such as those underlying partisan and/or overly-confident political, religious, and/or philosophical perspectives. Significance Statement Psychedelics are capturing interest, with efforts underway to bring psilocybin therapy to marketing authorisation and legal access within a decade, spearheaded by the findings of a series of phase 2 trials. In this climate, a compelling unified model of how psychedelics alter brain function to alter consciousness would have appeal. Towards this end, we have sought to integrate a leading model of global brain function, hierarchical predictive coding, with an often-cited model of the acute action of psychedelics, the entropic brain hypothesis. The resulting synthesis states that psychedelics work to relax high-level priors, sensitising them to liberated bottom-up information flow, which, with the right intention, care provision and context, can help guide and cultivate the revision of entrenched pathological priors.
Full-text available
Background Recent research demonstrated the potential of psychedelic drugs as treatment for depression and death-related anxiety and as an enhancement for well-being. While generally positive, responses to psychedelic drugs can vary according to traits, setting, and mental state (set) before and during ingestion. Most earlier models explain minimal response variation, primarily related to dosage and trust, but a recent study found that states of surrender and preoccupation at the time of ingestion explained substantial variance in mystical and adverse psilocybin experiences. Objectives The current study sought to replicate the previous model, extend the model with additional predictors, and examine the role of mystical experience on positive change. Method A hierarchical regression model was created with crowdsourced retrospective data from 183 individuals who had self-administered psilocybin in the past year. Scales explored mental states before, during, and after psilocybin ingestion, relying on open-ended memory prompts at each juncture to trigger recollections. Controlled drug administration was not employed. Results This study replicated the previous model, finding a state of surrender before ingestion a key predictor of optimal experience and preoccupation a key predictor of adverse experience. Additional predictors added to the explanatory power for optimal and adverse experience. The model supported the importance of mystical experiences to long-term change. Conclusion Mental states of surrender or preoccupation at the time of ingestion explain variance in mystical or adverse psilocybin experiences, and mystical experiences relate to long-term positive change. The capacity to recognize this optimal preparatory mental state may benefit therapeutic use of psilocybin in clinical settings.
Full-text available
Naturally occurring and psychedelic drug–occasioned experiences interpreted as personal encounters with God are well described but have not been systematically compared. In this study, five groups of individuals participated in an online survey with detailed questions characterizing the subjective phenomena, interpretation, and persisting changes attributed to their single most memorable God encounter experience (n = 809 Non-Drug, 1184 psilocybin, 1251 lysergic acid diethylamide (LSD), 435 ayahuasca, and 606 N,N-dimethyltryptamine (DMT)). Analyses of differences in experiences were adjusted statistically for demographic differences between groups. The Non-Drug Group was most likely to choose "God" as the best descriptor of that which was encountered while the psychedelic groups were most likely to choose "Ultimate Reality." Although there were some other differences between non-drug and the combined psychedelic group, as well as between the four psychedelic groups, the similarities among these groups were most striking. Most participants reported vivid memories of the encounter experience, which frequently involved communication with something having the attributes of being conscious, benevolent, intelligent, sacred, eternal, and all-knowing. The encounter experience fulfilled a priori criteria for being a complete mystical experience in approximately half of the participants. More than two-thirds of those who identified as atheist before the experience no longer identified as atheist afterwards. These experiences were rated as among the most personally meaningful and spiritually significant lifetime experiences, with moderate to strong persisting positive changes in life satisfaction, purpose, and meaning attributed to these experiences. Among the four groups of psychedelic users, the psilocybin and LSD groups were most similar and the ayahuasca group tended to have the highest rates of endorsing positive features and enduring consequences of the experience. Future exploration of predisposing factors and phenomenological and neural correlates of such experiences may provide new insights into religious and spiritual beliefs that have been integral to shaping human culture since time immemorial.
Full-text available
Creative thinking and empathy are crucial for everyday interactions and subjective well-being. This is emphasized by studies showing a reduction in these skills in populations where social interaction and subjective well-being are significantly compromised (e.g., depression). Anecdotal reports and recent studies suggest that a single administration of psilocybin can enhance such processes and could therefore be a potential treatment. However, it has yet to be assessed whether effects outlast acute intoxication. The present study aimed to assess the sub-acute effects of psilocybin on creative thinking, empathy, and well-being. Participants attending a psilocybin retreat completed tests of creative (convergent and divergent) thinking and empathy, and the satisfaction with life scale on three occasions: before ingesting psilocybin (N = 55), the morning after (N = 50), and seven days after (N = 22). Results indicated that psilocybin enhanced divergent thinking and emotional empathy the morning after use. Enhancements in convergent thinking, valence-specific emotional empathy, and well-being persisted seven days after use. Sub-acute changes in empathy correlated with changes in well-being. The study demonstrates that a single administration of psilocybin in a social setting may be associated with sub-acute enhancement of creative thinking, empathy, and subjective well-being. Future research should test whether these effects contribute to the therapeutic effects in clinical populations.
A single dose of the serotonin 2A receptor (5-HT2AR) agonist psilocybin can have long-lasting beneficial effects on mood, personality, and potentially on mindfulness, but underlying mechanisms are unknown. Here, we for the first time conduct a study that assesses psilocybin effects on cerebral 5-HT2AR binding with [¹¹C]Cimbi-36 positron emission tomography (PET) imaging and on personality and mindfulness. Ten healthy and psychedelic-naïve volunteers underwent PET neuroimaging of 5-HT2AR at baseline (BL) and one week (1W) after a single oral dose of psilocybin (0.2–0.3 mg/kg). Personality (NEO PI-R) and mindfulness (MAAS) questionnaires were completed at BL and at three-months follow-up (3M). Paired t-tests revealed statistically significant increases in personality Openness (puncorrected = 0.04, mean change [95%CI]: 4.2[0.4;∞]), which was hypothesized a priori to increase, and mindfulness (pFWER = 0.02, mean change [95%CI]: 0.5 [0.2;0.7]). Although 5-HT2AR binding at 1W versus BL was similar across individuals (puncorrected = 0.8, mean change [95%CI]: 0.007 [−0.04;0.06]), a post hoc linear regression analysis showed that change in mindfulness and 5-HT2AR correlated negatively (β [95%CI] = −5.0 [−9.0; −0.9], pFWER= 0.046). In conclusion, we confirm that psilocybin intake is associated with long-term increases in Openness and – as a novel finding – mindfulness, which may be a key element of psilocybin therapy. Cerebral 5-HT2AR binding did not change across individuals but the negative association between changes in 5-HT2AR binding and mindfulness suggests that individual change in 5-HT2AR levels after psilocybin is variable and represents a potential mechanism influencing long-term effects of psilocybin on mindfulness.