Why the Pineal Gland Became a Spiritual Fixation

TOGETHER WITH

The word “science” is derived from the Latin root scire, which means literally “to know.” It suggests a gradual, methodical process of stripping away the layers of misperception and misunderstanding separating our senses from a hypothetical base reality. And there are few ideas that have been more thoroughly cut away by the blade of science than that of the soul. 

Yet in the mid-seventeenth century, with the Scientific Revolution in full bloom, one of the most impactful thinkers in the history of Western philosophy made it abundantly clear that he not only believed in the existence of the soul, but that it could be traced back to a single, seemingly nondescript little piece of brain tissue known as the pineal gland.

“Although the soul is joined to the whole body, there’s a certain part of the body where it exercises its functions more particularly than in all the others,” René Descartes wrote in The Passions of the Soul, published in 1649. “I can clearly see that the part of the body in which the soul directly does its work is…a certain very small gland deep inside the brain…”

That “certain very small gland” — about 0.8 centimeters in diameter, the size of an eraser on the end of a pencil — has long held a singularly potent sway over the human imagination. 

It’s long been shrouded in myth; even if you have no familiarity with neuroscience or anatomy, you’ve probably heard the pineal gland discussed in its supposed connection with ancient philosophy and medicine. Today, it’s widely claimed — particularly in modern New Age and spiritual discourse — that ancient Egyptians and Hindus attributed spiritual significance to the pineal gland, casting it as a “third eye” that served as a gateway between physical and spiritual planes, the locus from which the soul’s divinity emanated. Those are historically inaccurate modern inventions, however; there’s no clear historical record that either ancient culture afforded spiritual significance to the pineal gland itself.

That hasn’t stopped legions of modern-day spiritual influencers from discussing this thimbleful of neuronal tissue as if it were imbued with supernatural power. (It’s true that the ancient Greeks identified the pineal gland as the physical location where pneuma, or spirits, entered into the human body; the famed Greek-Roman physician Galen referred to the gland as kônarion, Greek for “little cone,” based on its pine cone-like shape, which later informed the term “pineal.”). YouTube is littered with extended-focus and productivity music playlists (like this one) that claim to tune into the pineal gland, as if this will somehow unlock creativity and inspiration in the mind of the listener. There’s even an app on the iOS App Store called PinealApp, which has a library of audio tracks that “allow you to access, activate, and enhance the ‘jewel of the brain,’ the Pineal Gland,” according to its description.

At a purely anatomical level, it isn’t at all clear why such a tiny gland should be so captivating. One possible explanation, according to University of Greenwich psychologist David Luke, is its physical location near the center of the brain, which could be interpreted as a direct link to the subjective experience of selfhood. “Because we're heavily driven by our visual perception system, we perceive ourselves usually in the middle of our head,” says Luke. “It feels like we exist somewhere where our pineal gland is.”

Aside from that, there isn’t much that’s obviously physically remarkable about this gland. It stands out from other major parts of the brain because of its bilateral asymmetry — if you divide the human brain evenly between its two hemispheres, it’s one of the few parts that won’t perfectly mirror itself on either side — but this doesn’t exactly scream “seat of the soul,” as Descartes described it.

To understand the modern obsession with the pineal gland, we first need to examine its functional role.

Melatonin and Dreams

Like every other part of the human endocrine system, the pineal gland is responsible for releasing and regulating hormones — biochemicals which relay messages throughout the brain and body to initiate certain functions related to mood, development, metabolism, and other processes. Specifically, the pineal gland regulates the release of melatonin. 

While it’s probably best known as an over-the-counter sleep aid, melatonin is in fact an endogenous compound produced by the pineal gland to regulate your circadian rhythm, or sleep-wake cycle. Since we evolved to be diurnal animals — awake during the day and asleep through the night — this gland in the human brain uses the presence or absence of light, specifically high-frequency blue light, conveyed from the retinas as a cue to ramp up or slow down production of melatonin. (This is why sleep experts advise against staring at your phone before going to bed: the artificial blue light blasting from the screen tricks your brain into thinking that the sun is still shining, and thereby delays the release of melatonin.)

But at least in humans, sleep is more than just a vital biological function: it also produces dreams, which, to people obsessively geared towards weaving narrative out of inchoate data, have long acted as a fertile source for mythmaking and spirituality. This, perhaps, is another reason behind the perception of the pineal gland as an interface between soul and matter. “Since we spend about a third of our life in sleep, and it constitutes the realm of dreams, the pineal was seen as being vastly important,” says Dr. Steven Barker, an analytical chemist and professor emeritus of comparative biomedical science at Louisiana State University.

The DMT Link

In 1985, Dr. Rick Strassman was a recently appointed assistant professor of psychiatry at the University of New Mexico. He was also a longtime meditation practitioner with an interest in Eastern mysticism, and he’d begun to suspect that the pineal gland, with its modulatory role in melatonin release, could also play a causal role in certain altered states of consciousness. His research, however, quickly led him to the conclusion that melatonin wasn’t the spirit molecule he was looking for. 

After giving a talk about the pineal gland at Esalen in 1987, he was approached by the ethnobotanist and writer Terence McKenna, who, along with his brother Dennis would do more than almost anybody else during this period to rekindle popular interest in the class of drugs known as psychedelics. Since the passing of the federal Controlled Substances Act in 1970, these compounds had become politically and socially taboo. McKenna encouraged Strassman to try what was then a relatively obscure psychedelic compound: N,N-dimethyltryptamine, more commonly known as DMT. Just a few hours later, Strassman sat for his first DMT experience, with McKenna as his trip sitter.

A naturally occurring indole alkaloid present in many plants, DMT is also — for reasons that remain largely mysterious — found in the bodies and brains of some species of mammals, including humans. Like melatonin, it’s synthesized from the amino acid tryptophan. Starting in the middle of the last century, scientists started to suspect that this molecule, which in its exogenous form produces profound and rich visionary experiences, could be a so-called “schizotoxin,” a compound produced by the body and causing the hallucinations experienced by people with psychotic disorders, particularly schizophrenia. But like Strassman’s research into the psychoactive properties of melatonin decades later, that seemed to be a scientific dead end, and research into endogenous DMT lost traction.

Inspired by McKenna and by his own first experience with the drug, however, Strassman turned his attention to DMT. Following a pioneering study into the drug’s effects on 60 human volunteers — all of whom received intramuscular injections of the drug in a clinic at the University of New Mexico hospital — he published his findings in his 2001 book DMT: The Spirit Molecule. The book contained accounts from volunteers of Strassman’s DMT study, many of whom described encounters with supremely intelligent discarnate entities in an alien realm that was somehow more real than our everyday waking reality. Here, Strassman started to believe, could be the connecting link between the physical and spiritual planes he’d been looking for. 

In his book, he speculated that the pineal gland could serve as a biological center that regulates the flow of DMT in the brain, and perhaps releases a massive dose at the moment of death. Such an explanation seemed to gel nicely with the mystical experiences reported by many people who had gone through a near-death experience, or NDE.

Although Strassman had no biological basis on which to support his claims about the pineal gland, they have taken on a life of their own in the fringes of psychedelic culture that would soon start to flourish, thanks in no small part to the blueprint for clinical research he established with his landmark DMT study.

“Everyone who read [Strassman’s] book, and then everyone who commented on the internet, put this forward as Gospel,” says Luke, the University of Greenwich psychologist. “It became this dimethyltrypta-meme.”

Recent Revelations

Unfortunately for legions of psychonauts and spiritual influencers who claim otherwise, recent research has yielded strong evidence against the hypothesis that the pineal gland is linked to endogenous DMT, dreams, or mystical experiences.

Much of that work has been completed by Jimo Borjigin, a neuroscientist and consciousness researcher at the University of Michigan who studied melatonin for her doctoral thesis. After seeing the documentary of the same name that was released following the publication of Strassman’s book, Borjigin reached out to him with an offer to collaborate on a study to test his claim about the connection between the pineal gland and endogenous DMT. In 2013, Borjigin and Strassman, along with others (including Barker, the LSU chemist), published a landmark paper which, indeed, detected DMT in the pineal glands of living rats using a sensitive method called liquid chromatography-tandem mass spectrometry (LC/MS/MS).

Six years later, they coauthored another paper, along with Borjigin’s colleague Jon Dean, showing that rat brains produce a spike in endogenous DMT levels during experimentally induced cardiac arrest. That spike was recorded in both rats with intact pineal glands and in those whose pineal glands had been surgically removed. In other words, endogenous DMT production occurred independently of the pineal gland; something else was clearly at play. Moreover, additional research from Borjigin and others showed that rat brains produce a spike in a number of neurotransmitters, including dopamine and serotonin, at the moment of death.

Lessons

As is often the case in the history of science, research into the pineal gland has shown that physical processes are much more complicated than we originally suppose. It’s convenient to trace disparate phenomena back to a single source, but more often than not, we end up finding that they emerge from the dynamic interplay of many different, dynamically interrelated forces. 

The “soul” is a perfect example. From Aristotle to Descartes, Western philosophers confronted with the apparent gulf in intelligence between human beings and “lower” animals have reasoned that the human mind must be grounded in some kind of immaterial source, which some believed was divine in origin. More recently, the French philosopher Henri Bergson (1859-1941) postulated that life is endowed with an élan vital which animates and distinguishes it from inert matter. Discoveries in physics, chemistry, and biology, however, have led to the realization that life emerges not from some single spooky, immaterial substance, but from an unfathomably long and intricate process of evolution, while belief in an immaterial soul has also long since fallen out of fashion — at least in most scientific circles.

In the same way, it’s tempting to take a phenomenon as mysterious as dreaming, mystical experiences, or even consciousness itself and trace them back to a single piece of brain tissue. But as the mechanisms for studying neurochemical processes improve, this suspiciously neat picture of the pineal gland will probably continue to fracture into something much more complex. 

“There’s a strong desire to pin down this silver bullet, this one simple mechanism that’s going to explain it all; we’re like, it must be the pineal gland — it’s the ‘seat of the soul,’ it’s the key structure,” says DMT researcher Nick Glynos. “But when you think about nature and the universe, it's never one thing. This is a complex orchestration of many mechanisms and processes, and it's all happening synergistically to create this experience we have.”

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