Over the past decade, numerous open-label studies and early clinical trials have shown that psychedelics hold promise for the fast and possibly lasting relief of a wide range of conditions ranging from major depressive disorder, end-of-life anxiety, and obsessive-compulsive disorder to smoking, alcohol use, and eating disorders (e.g., Ko, Kopra, Cleare, & Rucker, 2023; Mitchell & Anderson, 2024; Sharma, Batchelor, & Sin, 2023).

Among the questions still to be resolved in this endeavor – and there are many, ranging from the role and nature of psychotherapy in the psychedelic-assisted therapy to commercialization and the question of who should lead psychedelic assisted therapy sessions – are questions related to the importance of the subjective aspects of the psychedelic experience. Are the hallucinatory experiences engendered by classical psychedelics necessary to their therapeutic action, or could a trip that doesn't go anywhere have the same effect on depression and other conditions? (Olson, 2021; Peterson & Sisti, 2022; Rasmussen & Olson, 2022; Yaden & Griffiths, 2021).

Of course, that leads to a deeper question. The psychedelic experience itself can, at least at times and under certain therapeutic circumstances, offer a suffering patient a journey into the core of the self and a visionary experience described by many as one of the most profound experiences of their lives (Griffiths, Richards, McCann, & Jesse, 2006, 2008; Hartogsohn, 2018). If such an experience can be discarded as unessential to recovery from a self-referential illness like major depression in favor of neurochemical processes alone with no phenomenological expression, what does that say about the superfluity of consciousness, or of any of the phenomenological experiences of our lives?

As a clinical psychologist who teaches doctoral courses in psychological interventions, I have a strong professional interest in this field. In addition, as a patient/participant in Psylodep 1, Imperial College Londonʻs first major test of the effectiveness of psilocybin for treatment-resistant depression in 2015 (Carhart-Harris et al., 2016), I have a strong personal interest in this discussion as well.

The psychedelic research field has grown exponentially over the last several years. A decade ago, the number of academic centers of research into psychedelics could be counted on one hand. Presently, there are new research centers and programs opening seemingly every month, from academic centers at several campuses of the University of California, the University of Wisconsin, Kings College London, Vancouver Island University in Canada, and Tel Aviv University, to independent programs operated by private psychiatric clinics across the globe. At the same time, hundreds of millions of dollars are being invested in this new pharmacopeia by companies around the world (Aday, et al., 2023). With these investments has come an understandable emphasis on one aspect of the psychedelic experience, the effect of these drugs on the neurochemical functioning of specific regions of the brain.

It's relatively straightforward, at least in theory, to relate some of the neurochemical effects of psychedelics to specific improvements in patients' functioning. For example, the disruption in long-standing canalization of brain circuits such as those within the default mode network, along with the facilitation of neuroplasticity and novel lines of neuronal communication, may be associated with an increased ability to break out of entrenched ways of thinking or feeling and an enhanced capacity to seek out and benefit from pleasurable life experiences (Carhart-Harris et al., 2023). Overcommitment to such a neuroscience-privileged approach to the psychedelic experience, however, is bound to miss or downplay the importance to the individual of the content of those new thoughts, and how an affected individual internalizes and incorporates those thoughts into their individual self-schemata. My professional and personal view, each informed by the other, is that while such efforts may be successful to a degree, they're akin to trying to develop an orange that delivers a health-promoting dose of Vitamin C, folic acid, and potassium, without any of the unique and extraordinary fragrance, taste, and texture that make an orange “the taste of summer,” as Sandra Dallas wrote (2014).

To be sure, some investigators do give careful consideration to the subjective aspects of the psychedelic experience. Researchers have examined the role of mystical experience, awe, and encounters with spiritual entities in the antidepressant effect of psychedelics (Griffiths, et al., 2018; Hartogsohn, 2018; Hendricks, 2018), and studies have noted the importance of internal events such as emotional breakthroughs, increased salience of intra- and interpersonal connectedness, and an increased capacity for psychological insight (Roseman et al., 2019; Watts, Day, Krzanowski, Nutt, & Carhart-Harris, 2017).

Even researchers who work with non-human participants have noted the importance of the subjective experience in humans. In a particularly succinct commentary on this point while studying the effect of psilocybin on rats' depression-like behaviors, Jefsen, et al. (2019) rather slyly noted, “In humans, psychedelic trips are often highly profound and meaningful, but we do not currently know whether this is the case in rats” (p. 218).

To some investigators, however, the psychedelic experience per se, with its vast range of possible specific qualia within what is generally a remarkably universal frame, is often dealt with as though it were epiphenomenal and of little interest. Online repositories of individuals' experiential reports such as the Erowid experience vaults and the Shroomery trip reports (Erowid, n.d.; Shroomery, 2002) are replete with stories of encounters with a numinous other, but to those who downplay the importance of the subjective psychedelic experience, they might as well be stories of taking a bus to work, or going to the corner store.

I entered the Imperial College study as someone with a long-standing history of double depression – episodes of major depressive disorder plus dysthymia, which had resisted treatment with multiple medications and psychotherapeutic approaches. Although I had never been hospitalized, engaged in self-harm, or attempted suicide, I often felt fated and resigned to an early death, and thus sought out one of the early contemporary psilocybin trials.

At one point during the first of my two trips at Imperial College Hammersmith Hospital – an initial “mild dose” of 10 mg – I was lucid enough to be talking with the study's director, Dr. Robin Carhart-Harris (now at UC San Francisco), who was standing in a corner of the room. Standing next to him, just as clearly and objectively as I saw Robin, I saw Death in the persona of the Grim Reaper – the full-on character from so much Western imagery, a greater-than-life-size skeleton dressed in a black, hooded robe and carrying a scythe.

I looked at Death, Death looked at me, and – calmly and amicably – we struck up a conversation, as if between two old friends, beginning with, “Oh, hello. How are you doing?” and “Not bad, thanks. How are you?”

Over the next several minutes, in addition to catching each other up on what we'd been doing recently (and Death found the whole pseudo-60's hippie look of the hospital room quite hilarious), we came to an understanding. We both acknowledged that, like anyone else, I would go with Death when he called for me one day, but – and this was the important part – this was not that day.

Today, nearly nine years later, if I'm having a bad day, I can still sit down in my living room and invite an imaginal Death in for a nice cup of tea. Of course, I'm no longer tripping, so I don't hallucinate the Grim Reaper the way I did that day, but I can remember the perceived reality of that conversation in just as much detail as one I might have had with a close friend, and I can come away from a new imagined conversation with the same self-compassionate self-understanding that I felt while in the treatment room at the hospital.

Death was not the only character I met on my two psilocybin experiences in the hospital, which often took on a religious tone. I began the first trip by floating down a river accompanied by Buddha and Quan Yin; I ended the second by dancing for and finally becoming Shiva, destroying what had been to give room to create what was to be. In between, I had an intimate conversation with an unseen Jesus. who reminded me of his commandment to love everyone, and who, when I very tearfully asked, “Even me?” replied with a whisper in the words of the well-known meme, “Did I stutter?”

To the extent that our emotional life is a product of our experience and our interpretations of our experiences, I find it hard to imagine that any benefit I received from my participation in the study would have been as strong and as long-lasting without those particular hallucinated aspects of my experience, in which God – several gods, actually – told me, directly and personally, “You are our child, and you are loved.” Regardless of the true nature of those experiences (and I remain ontologically agnostic), one cannot sit and chat with Death or walk and talk with gods without being fundamentally changed.

I'm well aware that my experience was unique. Obviously, not everyone who takes psilocybin will have the same journey, meet the same characters and archetypes, see the same images. But while the journey and the cast of characters may differ, we know that many people who take a strong enough dose of a psychedelic, at least in certain therapeutic combinations of set and setting, will have an often-healing felt experience of another reality, one that their existing images of their self, their world, and their future simply cannot contain.

Our thoughts – and, during psychedelic experiences, our visions – may be the product of our neurons and neurotransmitters, but we are more than that. We are creatures who can almost literally feel the burning from the very fires of hell in the midst of depression, and who, in moments of relief and awe, can listen to a Puccini aria and hear the voices of angels. We may not have an answer to the hard problem of consciousness (Chalmers, 1995), but regardless of our capacity to understand it, our consciousness is, and whether we reach the depths and heights of hell and heaven, or only muddle around the smaller vales and hillocks in-between, for most of us, our phenomenal experience is all that is – all that makes us who we are, and all that gives our brief lives meaning.

It may well be that psychopharmacological research will develop drugs that can provide many of the psychotherapeutic benefits of psychedelics without any of the risks inherent in voluntarily transporting oneself outside the boundary of ordinary reality. But given the potential of psychedelics to allow someone to so viscerally experience a new phenomenal consciousness of self – to converse with the gods within and to experience the possibility of transfiguration – I fear we'd be giving up far too much in return.

Given the choice between a vitamin C capsule and an orange, there's much to be said for choosing the orange.