Introduction Part IV: The Spirit of Psychedelics

Written By Michael Angyus

Introduction

Welcome curious friends to Psychedelic Neuroscience, where we use advances in psychedelic research to learn about brain, mind, and soul. I’m your host, Michael Angyus, and today we’re going to stretch the imagination with discussions of subjective effects in the context of the science we have discussed previously. Today is when we get to focus on the mystery of psychedelics.

From molecule to mystery: introduction and caution

The mysterious nature of psychedelics has captivated the minds of scientists, artists, and mystics alike. I want this podcast to try and harmonize these distant modes of thought, forming a bridge between the molecule and the mystery. In this episode, I draw connections between the science of psychedelics and the spirituality of psychedelics, and since we are moving away from widely accepted ideas, I encourage you to hold these suggestions lightly. Additionally, the ideas discussed might conflict with some of your deeper beliefs, but I am only offering my own approach to harmonizing science and spirit, and I encourage you to use this to develop your own. I only argue that we should leave space in our minds for different types of thinking to coexist, the same way we should leave space for different types of people to coexist, even if the differences cannot be settled.

Psychedelics manifest the spirit: etymology

 ‘Psychedelic’ was initially coined from Greek words, ‘ψυχή’ (psychḗ) meaning 'soul’ or ‘mind' and ‘δηλείν’ (dēleín) meaning 'to manifest' or “to make clear”. To have a name that means the manifestation of the soul suggests that psychedelics are able to stimulate some of the most fundamental of our belief structures. For this to come from a molecule hitting some receptors in the brain, raises the mysterious, fascinating, and perhaps terrifying question: Can our spirit be completely reduced to activity in the brain?

I will argue that this question does not hold an obvious answer. Before we can look for one, we have to define what we even mean by these terms spirit and spirituality. To me, spirituality can be thought of as a set of tools, and these tools are what we use to guide our decision making when our logical thinking does not provide us with a clear direction. Spirituality tells us what to do when we don’t know what to do. In other words, it is our gut feeling, it is our message from God, it is our mysterious voice from the subconscious. Whichever language we use to describe it, there are always moments when concrete understanding falls short, when “knowing” falls short, and we are left to put our faith in something other than the logical approach. This is where we often differ in beliefs, because at the end of the day that’s what they are: beliefs. Beliefs do not bend to the crystalized structure of scientific truth, but instead can hold firmly against all reason. They have to hold firmly against all reason because that is what will help us recover stability and direction when the various dynamic features of life disseminate into complete chaos. Some of us use these tools more than others, but we all use them to navigate our lives. My proposition here is that the fundamental experience of what many of us call spirituality, the thinking we lean on when life gives us no clear path forward, is actually common between individuals, regardless of what they might conceptually identify with. This frames spirituality as an experience that is independent of any specific religion, and it frames religion as a specific set of tools drawn from exposures to the unknown.

In this episode, I am going to attempt to discuss the commonalities of spiritual experience, using their stimulation by psychedelics as a connection to their basis in biology. The ability of psychedelics to manifest the soul through stimulation of the brain gives us a chance to study the biological basis of spirit. And while this science will be something that can help us understand a conceptual basis for spiritual beliefs, it does not replace the need to develop and lean on spiritual beliefs, for these are tools that we can (and should) use to guide us through our lives.

Psychedelics and religious practice

A simple support for the claim that psychedelics can produce spiritual experiences is their long historical relationship with religious practice. There is evidence for indigenous tribes using them in spiritual ceremonies for thousands of years (George et al., 2020) and evidence has even turned up for highly developed civilizations like ancient Egypt and ancient Greece for the use of substances in ritual (Muraresku, 2020). Stepping into modern day, we see indigenous tribes continue to use psychedelics in their ceremonies, and some branches of Christianity are beginning to incorporate psychedelics as an adjunct to their spiritual pursuits. Introduced to popular culture in the 1950’s and 60’s, psychedelic use for spirituality became famously associated with hippie culture. Borrowing certain spiritual teachings and practices from the east, this group underwent a mystical distancing from mainstream culture. One of the practices adopted was “mindfulness meditation”, which has formed a reciprocal bond with psychedelics as they have both grown in popularity.

Mindfulness meditation and psychedelics are both used by the general population with the intention of improving well-being. Studies on psychedelic use & meditation practice show that they are correlated in populations with improved well-being (Qiu & Minda, 2022; Simonsson & Goldberg, 2023; Azmoodeh et al., 2023), lending validity to the claim that they are working as intended. What’s interesting, though, is that they aren’t just working alongside one another, but instead interacting positively with each other. One study found that an introduction to mindfulness meditation before psychedelics can better prepare people for a psychedelic experience (Payne et al., 2021). Additionally, another study found that the long-term benefits of psychedelics are improved if participants develop meditation practices first (Griffiths et al., 2018). These studies suggest that mindfulness meditation can improve the experience, as well as long term benefits of psychedelics, but the relationship may actually go both ways. Studies have shown that experience with psychedelics can improve the depth of meditation reached by participants (Soler et al., 2016), and long-term benefits of meditation retreats have been improved by the addition of psychedelics (Smigielski et al., 2019). This relationship between psychedelic use and the spiritual practice of meditation makes me wonder what common neurological or psychological processes are taking place in the brain that both psychedelics and meditation seem to affect.

Perhaps it’s a shift towards a type of thinking that we are not so accustomed to, a type of thinking that exists beyond words, and perhaps beyond reason. A common experience on psychedelics is the feeling of a greater presence, which for many users can be interpreted as an encounter with God (Griffiths et al., 2019; Yaden et al., 2017). These encounters can leave a potent impression. In a large survey (N = 2561), more than half of the participants that previously identified as atheist no longer did so after an experience with DMT (Davis et al., 2020). These impressionable encounters with something greater fit nicely into our operational definition of spirituality. It’s possible that psychedelics are helping people communicate with something other than that logical mind, and different people may conceptualize that experience in different ways.

Language is not all of reality

For me, this common experience of spirituality, whether reached through meditation or with psychedelics, points out a common assumption that we make during our regular daily lives that seems to be dissolved by these experiences. That assumption is that the thoughts in our head that we use to describe reality are indeed reality itself. What I mean is that there is something about psychedelic and meditative experiences that helps us observe our thoughts from a distance, rather than accepting them as truth. To separate thought from self, we have to recognize the level of abstraction on which ideas interact in our minds that sits beyond the verbal train of thought. This is the area of the mind which an artist taps for creation, finding ways to express the undeveloped feelings churning within the mind’s eye. It is a place beyond logic. A place beyond words. A place one step closer to spirit, where our emotions dance together before they can be named. It is a place where stories are born, but these stories are never perfect depictions of the experience that they draw from. No matter the medium, whether it be words, pictures, music, or dance, the deeper feeling that inspired it will always be something separate from its description.

Not only is an artist aware of this disconnect between experience and language, but neuroscientists also recognize the layered nature of the mind, as well as the limitations the brain has when attempting to pass information between these layers. For example, the sensory levels of the brain create abstract representations of what the eyes, nose, ears, mouth, and body feed to them. These abstractions are not the final result that you experience, but premature representations that are then spun around in the higher levels of the brain to be processed and compared with each other so that a cohesive depiction of reality can be produced. Importantly, we neuroscientists recognize that these abstractions will always fall short of the true reality they represent. This is the truth of any translation, whether it be translating reality into inner experience, or translating the inner experience into words, pictures, or sounds, descriptions are always different from that which they are describing.

Some things seem to escape explanation more than others. It’s as if these phenomena are deeper within the brain’s layers of abstraction, existing in a more complex form that cannot be easily understood by “us” – the conscious mind that observes the senses. It’s in this deeper space that I think the wisdom of spirituality is generated, and it’s possible that psychedelics and meditation both shift the mind’s eye towards this confusing space.

The fact that a single molecule can shift our brain towards this spiritual state suggests a neuroscientific basis for spirituality. In the next sections, I’m going to bring together the research on the neuroscience of psychedelics with common characteristics of spiritual experiences.

The hero’s journey and psychedelics

To study the process of a spiritual experience scientifically, we have to have some way to measure these experiences. Researchers over the years have developed and refined the mystical experience questionnaire (MEQ) (Barrett et al., 2015) to measure the mystical aspects of a psychedelic experience. The MEQ was initially developed to try and identify the things that are common across spiritual experiences, untethered to a specific religion, making it a useful tool in the study of spirituality more broadly. High scores on this scale have been correlated with positive long-term outcomes of psychedelic assisted therapy in numerous studies (Griffiths et al., 2008; Griffiths et al., 2006; Griffiths et al., 2011; Barsuglia et al., 2018), which suggests a relationship between spirituality and well-being.

To dig into the experience of spirituality from an angle that will tie nicely with the neuroscience, I’m going to bring in Joseph Campbell’s hero’s journey (Campbell, 2003). Similar to the approach of the mystical experience questionnaire, Campbell derived his hero’s journey from a broad review of cross-cultural and historical religion and mythology to outline a common theme: “A hero ventures forth from the world of common day into a region of supernatural wonder: fabulous forces are there encountered, and a decisive victory is won: the hero comes back from this mysterious adventure with the power to bestow boons on his fellow man.” In every hero’s journey we have a stage in which the hero becomes uncomfortable and uncertain. Their character is challenged by an adventure away from home, and they must take the necessary risks and sacrifices that ultimately lead to their success. The transformational experience is often described as a rebirth because they sacrificed themselves to become what the challenge demanded of them. After they adopt this new self, they integrate what they have learned into what was previously familiar, bringing the rewards of their exploration back home. This entire process results in a development of the hero. In other words, their soul is manifested.

 Pivotal Mental States

            The inspiration to use the hero’s journey as a tool to describe the spirituality of the psychedelic experience came from Robin Carhart-Harris and Ari Brouwer’s theory on Pivotal Mental States (PiMS) (Brouwer & Carhart-Harris, 2021). In their paper, they offer a neurobiological explanation for what have been previously labeled as “quantum changes” (Miller and C’de Baca, 2001) or “psychological transformations” (Paul, 2014). These experiences are moments of rapid destabilization of a previous identity or set of behaviors which is often associated with an experience that is deemed spiritual. Negative cases this transition can destabilize the individual to produce maladaptive behaviors we might deem as psychotic. PiMS suggests that these states are primed by chronic stress or neurotic traits which upregulate 5HT-2A receptor expression in the brain. With high concentrations of 5HT-2A, an acute stressor – some dramatic event or tipping point – releases a burst of serotonin that fills the available receptors and triggers the PiMS. These authors are suggesting that psychedelics are tapping into this natural system for transformation, noting that both experiences are often spiritual. Within the paper, they briefly cite Joseph Campbell’s hero’s journey (Campbell, 2008) as another, more mythological description of this same type of experience. In the interest of harmonizing science and spirit, I’m focusing on the hero’s journey for the remainder of the episode to tie the psychological and neurobiological findings to a mystical framework. Throughout this introductory series I’ve brought up the different levels of analysis on which we can investigate psychedelics. We have worked from the molecule, to the neuron, to the population of neurons, to the whole brain. At each level of increasing abstraction we are losing our certainty in what we are talking about, but we are also approaching the levels of understanding that are often most comprehensible to us. We are now working into a psychological and perhaps literary level of understanding. We can use the hero’s journey to examine the different stages and characteristics of this spiritual transformation, offering a very general but tantalizing connection between neuroscience and spirituality.

            As we learned in Episode 2, researchers have shown that psychedelics stimulate the growth of new connections between neurons (Vargas et al., 2021). While many researchers are trying to decouple the experience of psychedelics from this plasticity (Olson, 2022; Halberstadt et al., 2020; Hesselgrave et al., 2021), there is a large body of research that suggests the psychological experience is important for therapeutic success (Roseman et al., 2018; Griffiths et al., 2008; Zeifman et al., 2022). So while the PiMS article suggests that the process is part of the same system in natural occurrences, we still do not know the relationship between such uniquely transformative experiences and the neurobiological activity of the brain.

Curiously, upon reviewing the the far more general research area of neuroplasticity, Stanford Neuroscientist Dr. Andrew Huberman has arrived at a protocol for optimizing neuroplasticity that can be fit into the hero’s journey. He discusses his protocol during Episode #6 of his Huberman Lab Podcast, where he reviews studies on neuroplasticity to offer guidance on how we can optimize learning. He describes a two-stage process: 1) maximal focused effort towards a new task, and 2) Sleep or deep rest and recovery during which neural circuits physically rewire themselves. This runs parallel with the hero venturing away from home and then returning to integrate the rewards. In my own life, I can see this cyclical process of learning and growth and creation acting on multiple timescales. It can be as simple as pushing my comfort to learn a new scale on the guitar, or as complex as creating an entire album. The different processes of learning can all be broken down into a moment of discomfort in a new territory followed by an integration of new information with the rest of our knowledge.

While it’s hard to relate the cellular level of neuroplasticity to experiences of spirituality, we may be able to find neural activity associated with subjective experience using neuroimaging. In Episode 3, I discussed the idea of brain entropy, which is an adapted term from information theory used to assess the “exploratory behavior” of the brain (Carhart-Harris, 2020; Carhart-Harris & Friston, 2019). This measure of brain activity is basically assessing the repetitive nature of the brain’s activity over time, with more repetition being quantified as low entropy, and less repetition, more diverse or exploratory behavior, being quantified as high entropy. As I mentioned in episode three, one of the most consistent findings in psychedelic neuroimaging is that they increase measures of entropy across the brain. The increase in entropy by psychedelics is thought to be representative of the chaotic and unfamiliar experience of these drugs (Carhart-Harris, 2020; Carhart-Harris & Friston, 2019). In terms of our analogy to the hero’s journey, this might reflect the entire brain entering a state of exploration, venturing away from home. Consciousness research on brain entropy has shown it is decreased during sleep (Casali et al., 2013; Schartner et al., 2017, Zhang et al., 2001; Abasolo et al., 2015; Aamodt et al., 2021), and is even able to differentiate between different levels of coma (Casali et al., 2013). An active and awake brain has higher entropy perhaps indicating its exploration, while a sleeping brain has lower entropy because it is reinforcing and integrating pathways in the brain. We can perhaps think of entropy as a very general measure of where the brain is during its cycle between exploration and rest. Entropy could be a biological marker for the two phases of the hero’s journey. Remember that the hero’s journey captures what is maintained across various religions and mythology. It’s fascinating to think that the hero’s journey – a set of common elements maintained across culturally central stories – can find roots in the neuroscience. This early neuroimaging work, and psychedelic research more broadly, may be taking us towards a scientific understanding of our spirituality. This work can show us, on a new level, the ways in which we are similar, giving us a more concrete understanding of what makes us human.

In the next sections, I’m going to use the psychological research on psychedelics to examine some more specific elements of the hero’s journey, moving from our simplified, two-stage process to the more specific elements of Joseph Campbell’s analysis.

The psychedelic experience demands that the hero act with faith

The psychedelic journey is unique from those of other illicit drugs in that it does not guarantee a pleasant experience (Barrett et al., 2016). In fact, when Humphry Osmond coined the term ‘psychedelic’ in a letter he wrote to Aldous Huxley in 1956, his exact words were, “To fathom hell or soar angelic/Just take a pinch of psychedelic.” Borrowing concepts from dynamical systems theory, psychedelics have been suggested to shift the brain towards a critical state (Carhart-Harris, 2018; Carhart-Harris & Friston 2019; Girn et al., 2023). One characteristic of the critical state is high sensitivity to perturbations from which the system is slow to recover (Hancock et al., 2022). Subjectively, this manifests as a deeply vulnerable state in which the individual could be thrown into heaven or hell by normally insignificant psychological material. Our interpretations of the world are what make us who we are, so when this familiar self is wiped away, our conscious mind enters a new mental territory. This may be another perspective on the commonly discussed psychedelic induced “ego-dissolution” (Nour et al., 2016). This is akin to the hero venturing away from home.

 

            “You cannot discover new oceans unless you have the courage to lose sight of the shore”

                                                                                                                        -Andre Gide

We have to venture away from home if we want to change. In psychedelic preparation sessions one of the key points emphasized is to trust the experience and surrender to it. This kind of test of faith is a common feature of the hero’s journey. A classic example is Luke Skywalker (a walker of the sky, certainly indicative of someone who spends time away from ‘the shore’ mentioned in the above quote by Andre Gide) putting his trust in the force. This recurring theme throughout the movie comes to fruition at the moment of his final victory, when he sets aside the missile guiding computer and instead puts his faith in the force to make the fatal blow that destroys the death star. Psychedelics appear to knock out our own computer systems without our choice, reminding us of our ultimate vulnerability as human beings and driving us to put our faith into something outside of ourselves. An important component of faith is the assumption that the forces that are now in control are inherently good, and some researchers have developed scales to measure this faith. By asking questions about willingness to surrender before the person takes the drug, studies have found that it improves the likelihood of positive and even mystical experiences (Russ et al., 2019a; Russ et al., 2019b). It may therefore be fundamental to a positive psychedelic experience that the individual develops faith, surrendering to the forces that have taken control, under the assumption that these forces are inherently good. What the psychedelic user puts their faith in seems to differ between individuals, but the language we use around faith might be something other than the faith itself. Faith might not be something we can understand in a way that can be explained, yet we seem to gain an intuition for its necessity through our respect for the hero’s journey.

 

Religion: joining again

Psychedelic research on ‘connectedness’ has shown that participants report improvements in their connectedness to themselves, others, and the world after they finish a psychedelic journey (Carhart-Harris et al., 2018). What exactly is meant by connectedness is unclear, but perhaps the vulnerable and transformative process of the hero’s journey allows the individual to be molded by the experience. By surrendering themselves to be transformed, they find themselves connected to the things that molded them. If we take the word religion down to its Latin roots, we have and ‘ligos’ (to join) and ‘re’ (again). This interaction with the world does more than manifest the hero, it also connects the hero to the broader world through their vulnerability to it.

 

Joining again with people

When a hero ventures into new territory, it’s important there are mentors and helpers encountered along the way. They usually give some unique piece of information that the hero can take with them to make their decisive victory. Sticking with our Star Wars example, Obi Wan’s voice echoes in Luke’s head as he faces his ultimate challenge, “Use the force Luke”. Similarly, psychedelic trips are known to be more positive and mystical when there is a positive relationship between guides and participants (Kettner et al., 2021; Murphy et al., 2021, Kamilar-Britt et al., 2023). These guides cannot solve the problems for the participant, but they can give advice and wisdom that can be used in a critical moment.

Regarding the discussion of faith, it isn’t clear whether the participant is putting their faith in the guide, the knowledge, or something else. I would argue that a spiritual experience does not have to involve a god or the universe but could simply involve putting faith in a community of other human beings. Psychedelics improve prosocial behaviors such as decreasing scores on narcissism (van Mulukom et al., 2020) and increases in empathy (Pokorny et al., 2017; Mason et al., 2019; Dolder et al., 2016). Despite the hero emerging victorious, there is usually a humble component to their nature. This could be related to the realization of one’s own fragility, which triggers in them compassion and empathy towards other human beings who share in their fragility.

Connecting with others is a core element of religious and spiritual practice. As social creatures we have the ability to shift our interests from ourselves to other people and even other organisms who may be helpful to us. Calling those other organisms “who’s” rather than “it’s” may be an evolutionary capacity that motivates our support for social and ecological systems. If we dehumanize groups, we can easily act indifferently toward them, which can be seen in wars and oppression. Psychedelics appear to increase our anthropomorphic tendancies, with studies showing increased attributions of consciousness to non-human things of the world after a single psychedelic experience (Timmerman et al., 2021; Nayak & Griffiths, 2022). It was even shown that this shift was greater in participants who had more mystical experience (as can be seen in the figure from Nayak & Griffiths, (2022) below), suggesting a relationship between spirituality and anthropomorphizing. I would argue that this increased attribution of human qualities improves the ability to form communities, a core aspect of most religious practices.

  

Figure 1: From Nayak & Griffiths, (2022)

Closing

The scientific research around psychedelics has helped their public image shift into a more credible and respectable movement. The reason for this might be that our western culture has come to trust hard science much more than the flexible stories of religion and myth. While the rigid nature of science has done spectacular things, it is important to recognize the areas of life in which science does not yet provide useful approaches. Psychology and neuroscience may be the early stages of a mental and spiritual science, but when we compare our success rates in treating the body vs the mind, we find it’s easier to replace someone’s heart than it is to cure their depression. While the various religions of the world tend to conflict with each other in specifics, we have to recognize that their teachings have survived for thousands of years, laying the bedrock for our modern social and cultural interactions in ways we cannot possibly imagine. We therefore should not abandon these teachings but instead do our best to salvage the meaning behind them, for these are what guide us in what to do when we don’t know what to do.

In this episode, I’ve used the hero’s journey to describe the spiritual effects of psychedelics because it appears that spiritual experiences are best described using stories rather than scientific language alone. Joseph Campbell intended to find themes and teachings that survive across religion and myth, a universal experience which to me indicates a potential biological underpinning of spirituality. With psychedelics we find that this experience can be stimulated using a chemical, a chemical of known structure, that poetically resembles the shape of a key. A key to that mysterious 5HT-2A receptor. A key to the God button. This may be the key to understanding the neuroscience of spirituality, a task that may frighten those who hold specific beliefs about spirituality. To me these discoveries will not invalidate spiritual experiences but instead validate them, providing a scientific explanation for their existence without reducing the insight that is taken from them.

If psychedelics are a way to stimulate the hero’s journey, then what a powerful tool they might be for the personal development of human beings. Acting as a spiritual training ground, psychedelics may provide a universal stage on which individuals can deeply explore the various religious and mythological texts that have guided them through their naturally induced pivotal mental states. Within this secular spirituality we may better understand the diversity of the pursuit of happiness, opening our minds to the different ways people find meaning and stability in life.

How a molecule is able to evoke these experiences is still very much a speculation, but the surge in research interest and advent of new neuroscientific tools may help us reach some firm answers in the near future. These answers will help us understand the connection between molecule, brain, and spirit, and I will explore these scientific findings in the episodes to come.

In this episode, I chose to stay close to the spiritual development that psychedelics bring, but I want to add that the diversity of psychedelic experiences is vast. Future episodes will expand on the science behind the numerous topics not discussed, including music enjoyment, cognitive flexibility, creativity, social connection, psychosis, consciousness and much more. I hope that this introductory series has given you the context necessary to joyfully explore these topics in the coming episodes.

 

Welcome to Psychedelic Neuroscience

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Introduction Part III: Neuroimaging and Models of Psychedelic Action