Education
Psychedelics 101
A plain-language introduction to psychedelic medicines — how researchers think they work, and how they are being studied in supervised therapy.
A brief history
Psychedelics have been part of healing and spiritual practices for centuries. They entered Western science in the mid-20th century — Albert Hofmann’s synthesis of LSD and R. Gordon Wasson’s documentation of psilocybin mushrooms sparked a wave of research in the 1950s and 60s.
Most of that research stopped when the compounds were criminalized in the 1970s. Over the last two decades, a new generation of clinical studies has renewed scientific interest in their potential role in mental-health care — the basis of today’s psychedelic-assisted therapy.
What are psychedelics?
A group of compounds that temporarily change perception, mood, and thought. In a therapeutic context they fall into a few broad classes, each with different effects and safety considerations.
Tryptamines
e.g. psilocybin
Tend to produce visual and emotional shifts and reflective, philosophical states over roughly four to six hours. Studied in relation to depression, anxiety, and existential distress.
Empathogen-entactogens
e.g. MDMA
Associated with emotional openness and a sense of trust while thinking stays clear. Studied largely in the context of trauma and PTSD.
Dissociatives
e.g. ketamine
Work through a different mechanism and are the most established in Canadian clinical practice today. Studied for treatment-resistant depression.
All of these are controlled substances. Access is only within authorized legal and regulatory frameworks.
How they work in the brain
Researchers are still mapping exactly how psychedelics act, but a few mechanisms come up consistently.
Serotonin 2A receptors
Most classic psychedelics bind to 5-HT2A receptors in brain regions involved in perception, emotion, and cognition.
The default mode network
They temporarily quiet the network tied to habitual, self-referential thinking — which may allow new perspectives to surface.
Neuroplasticity
They appear to promote new neural connections, opening a window of heightened flexibility in the days and weeks afterward.
Why integration matters
That window is why the integration phase — therapeutic work after a session — is considered central to lasting change, not the session alone.
Safety & considerations
Used in controlled, screened, and supervised settings, classic psychedelics have a comparatively low physiological toxicity and no known potential for physical dependence. The main risks are psychological — a challenging experience, or the potential to affect people with certain predispositions.
This is why comprehensive medical and psychological screening is essential before any treatment. Some conditions and medications — for example cardiovascular conditions, or psychiatric medications such as SSRIs or lithium — require particular caution and are assessed by a qualified clinical team.
Where the research stands
Psychedelic research is in an active renaissance, with clinical trials underway across several mental-health conditions. Early findings are encouraging, and some benefits appear durable.
It remains an emerging field: results vary, studies are ongoing, and psychedelic-assisted therapy is not a fit for everyone. Whether it is appropriate for any individual is determined with a qualified clinical team.
Is it legal in Canada?
The landscape is evolving. Most psychedelic compounds remain controlled substances, but Health Canada provides access through specific channels — the Special Access Program, approved clinical trials, practitioner training, and individual exemptions. ATMA CENA operates within these regulations and works to provide legal, supervised access for eligible clients.
Have questions about psychedelic-assisted therapy?
Book a free information call and our team will help you understand your options.