48 | New Scientist | 4 June 2022with them. The extent of that intensity became
clear to Roland Griffiths, also at Johns Hopkins,
who collaborates with Yaden, about two
months after he ran his first psilocybin clinical
trial, when volunteers returned to report on
their progress. “It wasn’t uncommon for them
to say: ‘That’s the most meaningful experience
of my life, on a par with the birth of my firstborn
child’,” he says. Indeed, a third of participants
in that study said it was the single most
spiritually significant experience of their life.
This led Griffiths to design the Mystical
Experience Questionnaire (MEQ ), which
tries to quantify the importance of spiritual
experiences during psychedelic therapy,
although he is at pains to point out that
the MEQ measures a “secular spirituality”.
Different research groups describe these
kinds of experience with different metrics, but
whether it is “ego dissolution”, an “experience
of unity” or an “emotional breakthrough”, they
are broadly equivalent. “These are all what I’d“ The intensity
of experience
predicts how
successful the
treatment
will be”
CO
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Counterculture icon Timothy Leary
coined the term “set and setting” in the
1960s to emphasise how someone’s
initial mental state, together with their
physical and social environment, deeply
informs their psychedelic experience.
Now, while some seek to make “trip-free
psychedelics” (see main story), Robin
Carhart-Harris is painstakingly searching
for the perfect therapeutic trip.
A neuroscientist at the University of
California, San Francisco, Carhart-Harris
last year opened a lab called Neuroscape
to untangle which circumstances lead to
the best outcomes for people undergoing
psychedelic-assisted psychotherapy, and
how brain-imaging technology can guide
that process. There, Carhart-Harris and
his colleagues can tailor the therapeutic
environment during the trip itself.
For example, they are testing guided
meditations to prepare participants, as
well as more active and engaged therapy
during sessions. They are also working
with musicians and film directors tocreate immersive audiovisuals of wild
landscapes, complimented with natural
scents. “The psychedelic experience is, in
a sense, a return to a simpler state,” says
Carhart-Harris. “Just to be reminded of
our essence seems to harmonise very
nicely with the psychedelic experience.”
Intriguingly, Carhart-Harris and
his colleagues are even developing
technology that could inform therapists
about their patient’s state of mind during
a trip without having to ask. “When
you’re a guide in psychedelic therapy
sessions, most of the time you’re just
guessing where someone is,” he says.
“Are they in a pretty good place? Or are
they in a struggle state?” The therapist
could intervene accordingly to create asafer, more nurturing environment
for psychedelic therapy.
No one knows what the brain looks
like in those struggle states, so Carhart-
Harris is combining deep-learning
algorithms with functional magnetic
resonance imaging (fMRI) of the brain
to build a picture of how subjective
experiences map onto physical
brainwaves. Scanning a small number of
volunteers many times will allow him to
create a portrait of psychedelic substates
and so map which kinds of brain pattern
correspond to different experiences.
Similar technology has already been
used to create algorithms that can
accurately predict what people are
dreaming about from an fMRI read-out.
Carhart-Harris hopes that figuring
out the “winning formula” could also
offer solutions for people with existing
psychiatric conditions like schizophrenia
and bipolar disorder. They are more
likely to have bad trips, and are therefore
generally seen as too high risk for
psychedelic-assisted therapy. “We
lack enough treatments for the really
hard cases, so it’s kind of a protective
motivation,” he says.The perfect trip
consider self-transcendent experiences,” says
Yaden. And the upshot is that the intensity
of these events predicts how successful the
treatment will be weeks or months later.
Griffiths suspects the experiences provide a
new template for how people view themselves
within the world, and so alter how they make
decisions going forward. Still, he says that
while subjective experiences are probably
necessary for positive outcomes, the question
isn’t settled. The only bulletproof test, he says,
is to give psychedelics to people who are under
anaesthetic and so are unconscious. “Those
studies are really difficult, but people are
making a stab at them,” he says.
In the meantime, others are working on
more holistic, theoretical models of how
psychedelic substances work – something that
goes beyond the existing mechanistic idea of
chemicals modifying brain cells. Working with
Karl Friston at University College London,
Robin Carhart-Harris, a neuroscientist at theA therapy room at
Neuroscape in San
Francisco, California