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

Abstract

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.

Full text

Four individuals’experiences during and
following a psilocybin truffle retreat in the
Netherlands
ANNA LUTKAJTISp
The University of Sydney, Australia
Received: November 9, 2020 •Accepted: February 22, 2021
Published online: April 14, 2021
ABSTRACT
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.
INTRODUCTION
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 (Griffiths 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, & Griffiths, 2014, Johnson, Garcia-Romeu, & Griffiths, 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 beneficial 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
beneficial outcomes (e.g., Doblin, 1991; Griffiths 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 (Griffiths et al., 2018), and significant changes to beliefs and worldviews
Journal of Psychedelic
Studies
5 (2021) 1, 22–32
DOI:
10.1556/2054.2021.00162
© 2021 The Author(s)
ORIGINAL RESEARCH
PAPER
pCorresponding author.
E-mail: anna.lutkajtis@sydney.edu.au

such as decreased self-identified atheism (Davis et al., 2020;
Griffiths 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 influence 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 field 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
specificfeaturesofspecific substances, which has implications
for the treatment of specific 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
reality”of 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.
1
Thesethemeswereiden-
tified 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.
METHOD
Participants
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 affiliation
was Atheist (n51) and Spiritual But Not Religious (SBNR)
(n53). Reasons for attending the retreat included “heal a
mental health condition (MH),”
2
“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
30–40 g) in the form of a tea. About 90 minutes into the
session participants could elect to take a second “booster”
dose of truffles (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.
Interviews
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 difficult
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
1
n511 (at the time of writing).
2
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.
Journal of Psychedelic Studies 5 (2021) 1, 22–32 23

brought them to the retreat, (2) describe the actual psilo-
cybin experience, and (3) describe their journey since the
retreat, including any significant after-effects and changes.
All participants followed this general approach. Follow-up
questions were used for clarification 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-identified 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.
RESULTS
Jay
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. Specifically, 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
person”who 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 “Calliope”just 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. It’s true. It’s
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 first real “wow”moment that I had, you
know, it was a very clear answer to my intentions about the
creative flow 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, it’s 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
account:
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 it’s part of this perfect system. So relax, everything’s
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 significantly 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 significant 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 confi-
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
father’s passing, saying, “now I know that there’s 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 Jay’s 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 aware”person.
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
24 Journal of Psychedelic Studies 5 (2021) 1, 22–32

for those who are managing it and using it properly in
responsible terms.”
Ian
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
Pollan’s 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
“mystical”part, a “psychedelic”part, and a cognitive-psy-
chological part. These parts were delineated based on a
temporal structure, with the mystical part occurring during
the first third of the experience, when the psilocybin effect
was at its peak. What Ian described as the “typical psy-
chedelic”part of his experience involved “traditional psy-
chedelic visual effects”and occurred about halfway through
his experience. One particularly salient effect he described
was being able to “see the music in 3D,”noting “It’sbeyond
what you can explain. But I could kind of stop it [the
music]andlookatitfrom3608... in a way you could stop
time and look at music kind of stretched out as time.”The
final part of Ian’s experience was more cognitive and
involved “relaxing without the blindfold and contem-
plating.”
During his interview, Ian used the allegory of Plato’s
Cave to explain and make sense of his psilocybin experience,
which he described as being quite abstract yet incredibly
profound. One of the most significant 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 difficult 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 “mystical”part –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 flowing through him and flowing
from him, and said that he could “send out”this love to
other people in the room. The emotional intensity of the
experience was so strong that Ian’s 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 love”and
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 significant revision of his work priorities and an
increased sense of awareness regarding his interpersonal
relationships with others. Ian also reported significant
changes to his health and wellbeing; in particular, he lost
20 kg in the year following the retreat. Weight loss was not a
specific 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 significant
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 first 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 darkness”that 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 that’s 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 “depression”because that’s a clinical word and it’s not
a clinical depression. But okay, let’s use the word just as a
description of a “darkness”that’s 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 into”and
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
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. Carol’s 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.
Journal of Psychedelic Studies 5 (2021) 1, 22–32 25

The first involved a significant change to her sense of self
that occurred early on; specifically Carol described
“becoming the room.”Carol found it difficult to articulate
this aspect of the experience as she said it “didn't make
sense”to her. She explained, “I had trouble understanding
that I had become the environment around me”and
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 Carol’s 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,
Jasmine’s face changed so that she looked like Carol’s
adoptive mother. Carol had been adopted as a baby, and her
adoptive mother had died when Carol was fifteen 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 first thing I
noticed is her face just like fluidly morphed ... And it was not
like, “Oh my God, I'm being tricked.”It’s 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 she’s alive, she’s dead. Like, same thing.
3
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, it’s 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, flow 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 Carol’s 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-
sition”for 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 understanding”that
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 out”of 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 “fifty 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
“revelation-ogen:”
it’s a revelation. It’s a revelation-ogen. Because basically it’s
showing you, what’s 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 believes”in 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
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 people”and 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 Ben’s psilocybin
experience involved a period where he “became”his
3
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
like’thing.”
26 Journal of Psychedelic Studies 5 (2021) 1, 22–32

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 “I”wasn't there.
Ben described the experience as feeling unquestionably
real, saying “it’s 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 wife’s
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 Ben’s experience involved a
period where he became an animal in a forest:
So there’s 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
I ended up just being an atom basically, in this forest
scape.
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 atom”in a “whole complex sys-
tem”and 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.”Ben’s 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 it’s 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, everything’s okay. You don't actually need
much from me”... it was sort of telling me, “you're
actually not that bad.”
Ben said that while he didn't think he had a “full mystical
experience,”the experiences he did have “definitely changed
my understanding of my place in the world and my human
life and my connectedness to others.”He said he received
clarification regarding “what it means to love”and 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 problem”and 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-
nificant after-effect that Ben reported was a new interest in
spirituality, consciousness, psychedelics and quantum
physics, which he said has been “life-defining,”explaining
“it’s 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
Gender
Identity
Male Male Female Male
Ethnicity Caucasian Caucasian Caucasian Caucasian
Prior
Psychedelic
Use
None None None None
Education Master's
Degree
Master's
Degree
Master's
Degree
Bachelor's
Degree
Religious
Orientation
SBNR Atheist SBNR SBNR
Psilocybin
Dose
High High High High þ
Booster
Reason/s for
Attending
EC, IC,
ME
EC, PD IC, PD MH, ME
Months
Between
Retreat and
Interview
12
months
10
months
12
months
8 months
Journal of Psychedelic Studies 5 (2021) 1, 22–32 27

DISCUSSION
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 participant’s 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 significant
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
researcher.
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 participant’s specific 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 “connectedness”to 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 defines normal waking consciousness, ultimately
disrupting self-world boundaries and increasing feelings of
unity with others’and one’s surroundings”(Mason et al.,
2020, p. 2003). All participants in this study reported sig-
nificant 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 findings 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. Specifically, due to the inherent nonverbal nature of
such experiences, participants experienced difficulty when
trying to articulate significant changes to sense of self.
Additionally, participants all reported retaining a minimal
sense of a basic self (i.e., a sense of “awareness”or 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 “oneness”or “unity”) is a key
defining 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-force”to 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 nature”and 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
28 Journal of Psychedelic Studies 5 (2021) 1, 22–32

smell and touch. When I do that it’s like a little jolt of this
experience. It’s 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 into”or 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 cognition”has
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.
4
One participant mentioned a brief period of transient
distress, which was then transformed into a cathartic
breakthrough experience. This finding is consistent with the
results of a recent survey study which found that 84% of
psilocybin users who experienced a “bad trip”ultimately
benefited 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
point”in 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
identified 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
finding that is consistent with several survey studies of
psychedelic experiences (e.g., Davis et al. 2020; Griffiths
et al., 2019; Yaden et al., 2017). Finally, an unexpected
finding 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
benefit others.
5
Future research might investigate whether
this is a reliable and robust finding, 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 difficult 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
4
This was the case for both the sub-sample and the complete data set.
5
It should also be noted that all four case study participants, in their de-
briefing conversations with the researcher, expressed their desire to
contribute to psilocybin research in the hope that it might benefit others.
Journal of Psychedelic Studies 5 (2021) 1, 22–32 29

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-
reflective journaling and breathwork. While an in-depth
analysis of how these factors might shape participant’sex-
periences is beyond the scope of this article, future research
will consider the influence 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 truffles
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 30–80 g.
The study of the effects of psilocybin when consumed in
whole truffle 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 influence 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
truffles 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.
ETHICS STATEMENT
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.
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32 Journal of Psychedelic Studies 5 (2021) 1, 22–32