Your Brain Is Glowing: Biophotons And The Frontiers of Neural Communication

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Sit in a sealed, pitch-black room. Tape the cracks. Kill the lights. Hold your hand up an inch from your face — you see nothing. Total darkness.

Except it isn't.

Right now, your brain is emitting light. A faint glow of photons, leaking through your skull, as the honest exhaust of your thinking. And in 2025, a Canadian-led team measured that glow from outside the head — and watched it change with what people were thinking.

In this episode we explore:

💡 Why the "hungry brain" glows like a microscopic bonfire

🧠 Whether neurons might whisper to each other in light

⚛️ The wild (and heavily debated) quantum-brain speculation

🩺 Photoencephalography — a gentle, needle-free, radiation-free way this glow might spot disease years early

🌍 The mind-bender: your inner light may hum in time with Earth's magnetic field

We keep it honest, too — including the physicists who think the signal is overstated. Come for the wonder, stay for the rigor.

References

Biofield in neural communication: A review and conceptual framework

Exploring ultraweak photon emissions as optical markers of brain activity

This is Heliox: Where Evidence Meets Empathy

Independent, moderated, timely, deep, gentle, clinical, global, and community conversations about things that matter.  Breathe Easy, we go deep and lightly surface the big ideas.

Transcript

Speaker 1: 0:25

This is Heliox, where evidence meets empathy. Independent, moderated, timely, deep, gentle, clinical, global, and community conversations about things that matter. Breathe easy, we go deep and lightly surface the big ideas. I want you to try a little thought experiment with me today. Just imagine you are sitting in a pitch black room. And I don't mean like your bedroom with the curtains drawn. I'm talking about total, absolute sensory deprivation.

Speaker 2: 1:03

Right, like deep cave darkness.

Speaker 1: 1:05

Exactly. You've taped over every single crack under the door. You've completely powered down your phone. There are zero windows. It is just you sitting there in this absolute void. And now in this total darkness, you hold your hand up like inches from your face.

Speaker 2: 1:20

And you can't see a single thing.

Speaker 1: 1:21

Right. Nothing. You would assume, quite logically, I think, that you are enveloped in complete and utter darkness.

Speaker 2: 1:28

Well, yeah. I mean, that is the assumption humans have made for basically all of history, right? That a sealed room without a light source means a complete, absolute absence of photons.

Speaker 1: 1:38

But here is the shocking, honestly mind-blowing biological truth we are exploring today. You are not in total darkness because right now, literally, as you are listening to this deep dive, your brain is emitting light. Your head is actually glowing in the dark.

Speaker 2: 1:52

It's so wild to think about because, you know, we always picture the inside of the skull is this dark sealed vault. Right. Where the brain just quietly conducts its its electrical and chemical business. In total secrecy. Exactly. So finding out there is an entirely different physical phenomenon happening. Actual light being generated in the tissue, it completely upends our intuitive understanding of our own biology.

Speaker 1: 2:18

It really does. So today our mission is to explore this mysterious phenomenon. We are looking at what researchers call ultra-weak photon emissions or UPEs. You'll also hear them called bio-photons. We want to figure out where this light is actually coming from.

Speaker 2: 2:33

And we are going to dig into whether our neurons are, you know, secretly communicating using a kind of biological fiber optic network.

Speaker 1: 2:40

Which sounds like sci-fi, but we're going to get into it. And we are also going to look at how scientists are building a completely new non-invasive way to read our minds using nothing but the ambient glow of our own thoughts.

Speaker 2: 2:50

It's a huge topic.

Speaker 1: 2:52

Yeah.

Speaker 2: 2:52

And we are pulling from two really fascinating papers to guide us through this. The first is a comprehensive conceptual review published in Progress in Biophysics and Molecular Biology.

Speaker 1: 3:03

Which is a mouthful.

Speaker 2: 3:05

It is, yeah. But it lays out the theoretical groundwork, the hardcore physics of how light might actually operate in the brain. And then the second source is an experimental study from the journal iScience.

Speaker 1: 3:17

Right. And in that one, they didn't just theorize. They physically put human subjects in dark rooms with incredibly sensitive cameras to, like, actually measure this light and see how it correlates with active human thought. OK, let's unpack this. Let's do it. So to figure out what this light actually means, I feel like we have to start at the source, right? We have to look at the

Speaker 2: 3:38

Right. It accounts for only about 2% of your total body weight, but it demands 20% of your oxygen and 25% of your glucose. It is just constantly churning through resources.

Speaker 1: 3:49

And it's using all that energy to do what exactly? Pumping ions and stuff?

Speaker 2: 3:53

Yeah, pumping ions across cell membranes, resetting synapses, firing action potentials. It is a 24-7 operation. But all of that intense energy consumption, it happens through a process called oxidative metabolism.

Speaker 1: 4:07

Which is where oxygen comes in.

Speaker 2: 4:09

Exactly. And whenever you run an engine that hot and you use that much oxygen, you are going to produce exhaust. It's unavoidable.

Speaker 1: 4:15

Okay, so biological exhaust. What does that actually look like?

Speaker 2: 4:18

In biological systems, that exhaust takes the form of reactive oxygen species or ROS.

Speaker 1: 4:25

ROS. Wait, reactive oxygen species? Are those free radicals like the things we're supposed to eat blueberries for?

Speaker 2: 4:31

Yeah, you hit the nail on the head. You hear about these all the time in nutrition. They are the exact reason we are told to eat blueberries and drink green tea for antioxidants.

Speaker 1: 4:40

Okay, but let's break down what an ROS actually is, though, because I feel like it's not just some abstract toxin floating around.

Speaker 2: 4:46

Far from it. So when your cells break down glucose to make energy, they use mitokineria.

Speaker 1: 4:52

The powerhouse of the cell, right. Got to love high school biology.

Speaker 2: 4:56

Right. the classic definition. So think of mitochondria as these microscopic power plants inside the neuron. They pass electrons down a chain to generate power. And at the very end of that chain, oxygen is waiting there to basically catch those electrons.

Speaker 1: 5:11

Like a catcher's mitt.

Speaker 2: 5:13

Exactly. And usually it works perfectly and it just makes water. But sometimes an electron slips away early and it binds to oxygen prematurely. And this creates molecules like superoxide or

Speaker 1: 5:24

hydrogen peroxide, or hydroxyl radicals. And the defining feature of a radical, if I'm remembering

Speaker 2: 5:29

this right, is that it has an unpaired electron, right? Yes, exactly. And electrons hate being alone.

Speaker 1: 5:35

They desperately, violently want to be in pairs. So this rogue oxygen molecule is just like going

Speaker 2: 5:40

on a rampage through your brain tissue. It really is a rampage. It will violently rip an electron off the nearest available structure just to stabilize itself. And that's oxidation. That is the exact process of oxidation. These reactive oxygen species, they just collide with the biomolecules making up your brain. The structural proteins, the lipid bilayers that form the actual

Speaker 1: 6:02

walls of your cells, even your DNA. Yikes. So it's basically damaging everything it touches.

Speaker 2: 6:08

Right. When the ROS rips an electron away, it fundamentally alters the chemical structure of whatever it just attacked. And that creates these highly unstable, high-energy intermediate molecules.

Speaker 1: 6:20

And the review paper gets incredibly specific about this chemistry, which I thought was fascinating. It mentions structures called dioxetanes and tetraoxides.

Speaker 2: 6:27

Oh, the dioxetanes are so interesting. So when a lipid in your cell membrane gets oxidized, the carbon and oxygen atoms can actually be forced into these really tight four-membered rings. That is a dioxetane.

Speaker 1: 6:39

Okay, a four-membered ring, why does that matter?

Speaker 2: 6:41

Because from a chemistry perspective, a four-membered ring is under immense geometric strain. The bonds are bent in ways they really, really do not want to be bent.

Speaker 1: 6:50

Oh, gotcha. It's like taking a really thick piece of plastic and bending it in half, right? Until it turns white at the crease and it's just vibrating and about to snap, there is a ton of potential energy stored in that tension.

Speaker 2: 7:03

That is a perfect analogy. And just like the snapping plastic, these dioxetane rings cannot hold that state for long. They decompose. They literally break apart. But all that energy stored in that tension, it has to go somewhere.

Speaker 1: 7:16

Energy can't be created or destroyed, right?

Speaker 2: 7:18

Exactly. So when the ring breaks, that energy is transferred to an electron in the molecule, and it kicks it up into a higher energy orbit. This creates what physicists call a triplet excited carbonyl.

Speaker 1: 7:29

Okay, a triplet excited carbonyl. This is where I feel like the physics gets kind of beautiful. So you have this electron that has essentially been shoved up a ladder into a higher orbital. But physics demands equilibrium, right? The electron naturally wants to drop back down to its relaxed ground state.

Speaker 2: 7:47

Right. It wants to go back home. But the triplet part is the catch.

Speaker 1: 7:50

Because its spin flips.

Speaker 2: 7:51

Exactly. The triplet part means the electron's quantum spin actually flipped when it got pushed up the ladder. So it gets temporarily trapped on that higher rung. It literally has to wait for its spin to flip back before it's allowed to fall.

Speaker 1: 8:03

And it's just stuck there for a tiny fraction of a second. But when it finally makes that drop back down to the ground, boom. The excess energy is expelled from the molecule entirely. It is released as a photon.

Speaker 2: 8:16

Literal particle of light inside your wet, dark skull.

Speaker 1: 8:20

I mean, I just keep picturing the brain as this microscopic, wet bonfire. You have billions of neurons burning glucose and oxygen at furious rates. And the sparks flying off this fire are these excited molecules snapping and decomposing.

Speaker 2: 8:34

That's a great visual. And sometimes they emit light directly. Other times they bump into nearby molecules, things called chromophores, like flavor proteins or the hemoglobin in your blood. They transfer their energy to the chromophore, and then the chromophore is what flashes.

Speaker 1: 8:48

But we should probably anchor this in the physical reality of the scale, because it is a stunning visual. But when you say the brain is glowing, people might imagine something akin to like a firefly or those terrifying deep sea angler fish with the glowing lures.

Speaker 2: 9:04

Right, right. We definitely have to differentiate between actual bioluminescence and these ultra-weak photon emissions.

Speaker 1: 9:10

Because a firefly is using a highly evolved, highly specific enzyme called luciferase, right, the entire purpose of that chemical reaction is to create a bright, visible flash to attract a mate. It wants to be seen. It's super efficient.

Speaker 2: 9:25

Exactly. The brain, on the other hand, is not trying to light up a room. The intensity of this light is unimaginably dim. We were talking about an energy level of roughly 10 to the negative 16th watts per square meter.

Speaker 1: 9:37

Which means absolutely nothing to most people, including me.

Speaker 2: 9:40

Fair enough. Fair enough. Let me put it in practical terms. It basically means a few thousand faucons are being emitted per square centimeter of brain tissue per second.

Speaker 1: 9:49

Which is still hard to picture.

Speaker 2: 9:50

Well, think about the absolute lowest threshold of the human eye. Like the faintest possible glimmer you could perceive after sitting in a pitch black closet for an hour. that faint glimmer is exponentially brighter than this brain light. If a neurosurgeon removes a piece of your skull in a pitch black operating room, they are not going to look down and see your brain glowing. It is completely 100% invisible to human vision.

Speaker 1: 10:16

And even if it were a little brighter, the light has a massive physical obstacle to overcome just to get out into the world. I mean, the skull is an incredibly dense barrier.

Speaker 2: 10:26

It's basically armor.

Speaker 1: 10:27

Right. The sources note it's composed of hydroxycapitate crystals, which is the mineral part of bone, and that's woven together with collagen fibers. That matrix acts like a lead blanket for visible and ultraviolet light. It absorbs and scatters almost everything.

Speaker 2: 10:43

Although, and this is key, the longer wavelengths, specifically near infrared light, they do manage to sort of slip through the bone matrix and escape the scalp, which is really the only reason we are eventually able to measure it.

Speaker 1: 10:54

Okay, so we have established the biological reality here. The brain is burning massive amounts of energy. It's generating oxidative stress. And the physical breakdown of those molecules is constantly releasing faint flashes of light. But the unavoidable question that emerges from this, the thing I've been wanting to ask since we started, is about purpose.

Speaker 2: 11:15

Is it just exhaust or is it doing something?

Speaker 1: 11:18

Exactly. Is this just biological exhaust from the wet bonfire or is it a secret language? Are our neurons actually communicating with light?

Speaker 2: 11:25

So this brings us to the classical signaling hypothesis, because you have to remember the brain is fundamentally an information processing network. We know it relies heavily on chemical signaling.

Speaker 1: 11:36

Right, neurotransmitters like glutamate, dopamine, serotonin, just kind of floating across the tiny gaps between neurons, the synapses.

Speaker 2: 11:43

Right, and chemical signaling is incredibly reliable. It's very nuanced. But because it relies on physical molecules floating through a fluid environment, it is relatively slow.

Speaker 1: 11:53

Okay, but then you have the electrical signaling too.

Speaker 2: 11:55

Yes, the action potential zipping down the length of the neuron. This is much faster. It operates on the millisecond timescale. It allows you to, you know, pull your hand away from a hot stove before you even consciously realize you've been burned.

Speaker 1: 12:08

But the sources suggest a possible third mode of communication, light.

Speaker 2: 12:12

Right. Because what's faster than electricity? Light. Light travels at, well, the speed of light. It would be virtually instantaneous.

Speaker 1: 12:21

And the primary theory they propose for how this could actually work inside the brain revolves around the concept of optical waveguides.

Speaker 2: 12:28

Right, waveguides. So in classical physics, a waveguide is essentially any physical structure that guides electromagnetic waves in a specific direction.

Speaker 1: 12:37

Like fiber optics.

Speaker 2: 12:38

Precisely. The fiber optic cables running under the ocean that power our global internet, those are waveguides. They work on a principle called total internal reflection.

Speaker 1: 12:46

Okay, total internal reflection. Break that down for us.

Speaker 2: 12:49

So if the core of the cable has a different refractive index, meaning it has a different way of bending light than the material wrapping around the outside of it, the light hits that boundary between the two materials and it bounces back inward. It essentially gets trapped inside the core and travels down the line without leaking out.

Speaker 1: 13:07

Okay, so the researchers propose that axons, which are those long wire-like projections that connect one neuron to another, they might be acting as natural biological optical waveguides.

Speaker 2: 13:18

Right. And the anatomy of an axon makes it a really candleizing theory. Imagine you have a photon generated in the cell body, the soma. Instead of just shooting off randomly into the surrounding tissue, it enters the axon.

Speaker 1: 13:29

And the axon is wrapped in myelin, right? That fatty layer of insulation.

Speaker 2: 13:33

Exactly. The myelin sheath. Because the inside of the axon has a different refractive index than the fatty myelin sheath outside it, the theory suggests that the light could theoretically bounce along the inside of the axon, traveling all the way down to the synapse to deliver a light signal.

Speaker 1: 13:48

Okay, I have to be honest. I am having a really, really hard time buying this. Oh, why's that? Because we use hyper-pure silica glass for our fiber optic networks for a reason, right? Like, it has to be perfect. Have you seen close-up images of brain tissue?

Speaker 2: 14:03

It is extremely messy.

Speaker 1: 14:05

It doesn't look like pristine glass cables at all. It's this dense, wet, fatty, highly irregular sponge. How does a single photon of light, which we already established, is incredibly weak? How does it manage to travel down a biological tube without just bouncing off a stray protein and getting completely absorbed?

Speaker 2: 14:24

You're completely right to be skeptical. And the authors of the review paper actually highlight this exact vulnerability in the theory. The probability of light leakage in the brain is astronomically high.

Speaker 1: 14:36

It just seems impossible.

Speaker 2: 14:37

Because brain tissue is full of what they call structural discontinuities. Axons are not perfectly straight. They curve. They branch off. They vary in thickness. Plus, they are packed full of subcellular components like mitochondria and microtubules.

Speaker 1: 14:50

Right. They are anti-tubes.

Speaker 2: 14:51

Exactly. And every single one of those structures is an opportunity for a photon to scatter.

Speaker 1: 14:56

It's like trying to shine a targeted light signal through that environment feels like trying to shine a laser pointer through a bowl of cloudy chicken broth. You know, the signal would just wash out into a diffuse glow almost immediately. You'd never get a clear beam through it.

Speaker 2: 15:10

Cloudy chicken broth. That is, yeah, that's incredibly accurate. the attenuation, which is the loss of the signal strength over distance, would be massive.

Speaker 1: 15:20

So the signal would just die before it reached the next neuron.

Speaker 2: 15:23

Almost certainly. If neurons are communicating via classical light signaling, it implies the existence of highly sophisticated, highly targeted mechanisms to prevent that scattering. Or, you know, incredibly sensitive photon receptors at the synapses.

Speaker 1: 15:37

And do we have proof of those?

Speaker 2: 15:39

So far, the biological evidence for those specific structures is lacking. The waveguide theory works elegantly on paper, but the physical reality of the brain makes it incredibly difficult to sustain.

Speaker 1: 15:50

Okay, so if theory says the brain is too opaque and messy for optical fibers, we kind of hit a wall. But because classical physics struggles to explain how a light signal could survive the brain's environment, some scientists have taken this massive, almost sci-fi conceptual leap.

Speaker 2: 16:06

The quantum leap.

Speaker 1: 16:08

Right. They asked, what if the brain isn't a classical optical network? What if it is operating on the bizarre rules of quantum physics?

Speaker 2: 16:17

Yes, the quantum conundrum. The review paper actually dedicates a significant amount of space to exploring this area. It proposes that biophotons might not just be particles of light bouncing down a tube, like your chicken broth laser, but they could instead rely on quantum properties to transmit complex information instantaneously across the neural network.

Speaker 1: 16:38

Okay, we really need to unpack the quantum terminology here because it genuinely sounds like science fiction. They are talking about superposition, coherence, and entanglement. Let's start with superposition. That's the principle that a quantum particle like a photon isn't just in one state or another, right? It exists in all its possible states simultaneously until it interacts with something that measures it.

Speaker 2: 16:58

Right, the classic Schrodinger's cat idea. And then coherence is the requirement for that superposition to exist in the first place. It means the mathematical waves describing the photons maintain a stable, predictable relationship with each other. They act together in unison rather than randomly interfering with one another and crashing the system.

Speaker 1: 17:18

And then there is entanglement, which is the big one. Einstein famously called it spooky action at a distance.

Speaker 2: 17:24

Which is still the best description of it.

Speaker 1: 17:26

It really is. It's the phenomenon where two photons become so deeply linked that the state of one instantly dictates the state of the other, regardless of how much physical space separates them. You could literally put one entangled photon in your brain and the other on the moon. And if you measure the one in your head, the one on the moon instantly assumes the corresponding state.

Speaker 2: 17:47

Zero lag.

Speaker 1: 17:48

Yeah.

Speaker 2: 17:48

The appeal of the quantum theory for brain communication is obvious when you think about it. If bio photons are entangled, you completely bypass the problem of the cloudy chicken broth.

Speaker 1: 17:58

Oh, because they don't have to physically travel through the mess.

Speaker 2: 18:01

Exactly. It wouldn't matter how messy the physical path between two neurons is or how much the light scatters. Entangled photons could coordinate activity across vast, distant regions of the brain instantaneously without needing a clear physical channel to travel through.

Speaker 1: 18:15

Okay, but wait. I thought quantum computers, like the multi-million dollar rigs built by Google or IBM, I thought they had to be kept in these massive, perfectly sealed vacuum chambers. They do. Don't they literally cool them down to fractions of a degree above absolute zero just to keep a handful of qubits stable for, like, a few milliseconds?

Speaker 2: 18:35

Yes. The engineering is notoriously difficult.

Speaker 1: 18:38

So how on earth could a delicate quantum state survive in our brains? Our brains are 37 degrees Celsius and filled with sloshing salt water. It seems like the absolute worst environment for a quantum computer.

Speaker 2: 18:50

You have zeroed in on the exact reason why quantum biology is so fiercely debated right now. The paper categorizes this problem under the umbrella of biological noise. Biological noise. Right. Quantum states are essentially the most fragile phenomena in the universe. To maintain coherence and entanglement, a system needs basically total isolation from external interference. And as you pointed out, the human brain is quite literally the opposite of isolated. It is the ultimate noisy environment in three distinct ways.

Speaker 1: 19:21

Okay, let's go through them. The first barrier they mention is thermal noise.

Speaker 2: 19:24

Right. At 37 degrees Celsius, the brain is a roaring inferno from a quantum perspective. Heat is simply kinetic energy. It is molecular motion. At body temperature, every single molecule in your brain is constantly vibrating, rotating, and slamming into its neighbors.

Speaker 1: 19:39

Just nonstop microscopic chaos.

Speaker 2: 19:41

Exactly. So a photon trying to maintain a delicate superposition is going to be relentlessly battered by this chaotic thermal energy. Every one of those random collisions threatens to collapse the quantum state.

Speaker 1: 19:53

Wow. And then you have chemical noise.

Speaker 2: 19:56

Right. Because the brain is fundamentally an equeous solution. It is a wet environment. It is packed with water molecules, freely floating ions like sodium and potassium, and a constant soup of neurotransmitters.

Speaker 1: 20:06

And none of that is sitting still either.

Speaker 2: 20:08

No, these molecules are undergoing stochastic or random collisions. Furthermore, metabolic chemical reactions are happening continuously, everywhere, all at once. The local chemical landscape is shifting microsecond to microsecond.

Speaker 1: 20:22

So it's hot, it's sloshing around, and it's chemically unstable. And the final nail in the coffin seems to be structural noise.

Speaker 2: 20:30

This is a huge one. Laboratory quantum computers use pure, highly ordered crystalline structures. Everything is perfectly aligned.

Speaker 1: 20:37

But the brain is heterogeneous?

Speaker 2: 20:39

Extremely. It is a chaotic mix of varying protein densities, lipid membranes, fiber scaffolding, differing cellular architectures. A biophoton traversing this space faces a constantly changing physical medium.

Speaker 1: 20:51

So between the heat, the sloshing water, and the messy proteins, any quantum state in the brain is just completely doomed.

Speaker 2: 20:58

It undergoes a process known as rapid decoherence. The biological noise causes the quantum wave function to collapse almost instantly. Now, I will add a caveat here because quantum biology is a real emerging field.

Speaker 1: 21:10

Right, like the European robin. I remember reading about this, about how they navigate during migration.

Speaker 2: 21:15

For cryptochrome protein, yes.

Speaker 1: 21:16

Right, so they have this protein in their retina called cryptochrome. And when a photon of ambient light hits that protein, it supposedly creates a pair of entangled electrons. And then the Earth's magnetic field subtly alters how those electrons recombine, which essentially allows the bird to literally see the magnetic field.

Speaker 2: 21:36

Precisely. It's an incredible mechanism. And the cryptochrome in a bird's eye proves that a warm, wet biological system can harness quantum entanglement for a functional purpose, at least briefly.

Speaker 1: 21:48

So it's not impossible.

Speaker 2: 21:49

It's not impossible in nature. However, the authors of the Brain Review make it very clear. While the mathematics of quantum biophoton communication in the human brain are captivating, we currently lack the experimental proof.

Speaker 1: 22:00

We haven't found our version of the bird's cryptochrome.

Speaker 2: 22:03

Exactly. We haven't found the equivalent receiver in our neurons that would act as a stable quantum receiver. So for now, the quantum brain internet remains highly, highly speculative.

Speaker 1: 22:14

Okay, so if theory says the brain is too wet and noisy for classical fiber optics and too hot and messy for quantum communication, we are kind of at a theoretical dead end. The mathematics and the physics debates can only take us so far.

Speaker 2: 22:28

At some point, you just have to look at the real world.

Speaker 1: 22:30

Exactly. The only way forward is to stop doing math on chalkboards and start actually looking for the light, which means we need a completely dark room and some incredibly sensitive cameras.

Speaker 2: 22:41

And this is where we transition to the empirical reality of the iScience paper. The researchers designed an elegant, really fascinating experiment to capture these elusive photons directly from human subjects.

Speaker 1: 22:54

Right. They took 20 participants and placed them one by one into that pitch black, completely light-proof chamber we talked about at the very beginning of the show. And then they brought in the heavy machinery, photomultiplier tubes or PMTs. They positioned these devices just a few centimeters away from the subject's skulls.

Speaker 2: 23:11

And a photomultiplier tube is a marvel of engineering. It doesn't work like the camera in your smartphone. It relies on the photoelectric effect.

Speaker 1: 23:19

Okay, break that down for us. How does that actually catch a single solitary photon, though?

Speaker 2: 23:25

It's a great mechanism. Imagine a glass vacuum tube. At the very front end is a plate called a photocathode. When a single photon of light enters the tube and strikes a photocathode, it transfers its energy and knocks exactly one electron loose.

Speaker 1: 23:41

One electron is an incredibly weak electrical signal, right? That's got to be impossible to measure.

Speaker 2: 23:47

On its own, yes. But the tube contains a series of internal plates called dynodes, and each one is held at a progressively higher positive voltage.

Speaker 1: 23:55

Oh, I see. So the electron, because it's negative, gets pulled toward the first positive plate.

Speaker 2: 24:00

Yes. It accelerates and smashes into the first dynode, knocking three or four more electrons loose. And those electrons are immediately accelerated into the next dynode, knocking loose a dozen more.

Speaker 1: 24:11

So it's a cascade effect.

Speaker 2: 24:13

Exactly. By the time it reaches the end of the tube, that single initial photon has created an avalanche of millions of electrons. It amplifies the signal to the point where a computer can register it as a distinct electrical pulse. PMTs are actually the exact same technology used in deep underground neutrino observatories to detect the faintest flashes of light from cosmic interactions.

Speaker 1: 24:37

Wow. And in this room, they are just pointing them at a human head.

Speaker 2: 24:40

Yeah, right at the scalp.

Speaker 1: 24:41

And they specifically targeted two areas, right? The left occipital lobe, which is at the back of the head, and is primarily responsible for visual processing. And the right temporal lobe on the side of the head, which handles auditory processing, memory, and emotion.

Speaker 2: 24:54

Right. But they also pointed a third PMT away from the subject entirely, at a blank wall.

Speaker 1: 24:59

Why do that?

Speaker 2: 25:00

To measure the background photon noise of the room itself. Because even a pitch black sensory deprivation room has some stray ambient photons bouncing around. You have to establish a baseline to know what's coming from the brain versus the room.

Speaker 1: 25:14

Makes sense. What did they find when they analyzed all this data? What was the verdict?

Speaker 2: 25:18

What they found was definitive proof. The human brain UPEs showed a completely distinct, unique statistical signature that proved they were not just random biological noise.

Speaker 1: 25:29

Okay, the first thing they analyzed was entropy. Now, we usually think of entropy as like a measure of disorder or chaos, right? But in signal processing, it's a measure of complexity and information content.

Speaker 2: 25:41

Correct. And they found that the background light in the room had low entropy. It was flat. It was random. It was predictable. But the photons coming from the brain exhibited high entropy. The signal was textured and highly complex.

Speaker 1: 25:53

That is wild.

Speaker 2: 25:55

Furthermore, it showed much greater variability. The photon counts from the brain tissue were fluctuating dynamically over time, while the background light in the room remained largely static.

Speaker 1: 26:04

So it's the difference between, like, listening to the static hiss on a dead radio channel and suddenly hearing a complicated encrypted transmission. The UPEs from the brain actually had an architecture to them.

Speaker 2: 26:15

They absolutely did. And they also discovered a specific temporal rhythm to that architecture. When they looked at the spectral frequency of the light emissions, the brain UPEs were fluctuating at a frequency of under 1 hertz. To be precise, in the 0.1 to 1 hertz range.

Speaker 1: 26:32

Wait, meaning the intensity of the light coming from the brain was cycling, like pulsing up and down every 1 to 10 seconds.

Speaker 2: 26:37

Yes. The background room light did not pulse. The brain was glowing with this slow, measurable, deliberate rhythm.

Speaker 1: 26:45

That is just incredible to visualize. But the truly groundbreaking finding from the iScience paper, at least to me, came from the task-based analysis. Because they didn't just have the subjects sit there indefinitely doing nothing, right? They ran them through a specific two-minute cognitive tasks to see if the internal state of the brain actually affected the external emission of light.

Speaker 2: 27:06

Right. And the tasks were incredibly simple. For two minutes, just sit in the pitch black room with your eyes open. Then for two minutes, sit in the pitch black room with your eyes closed.

Speaker 1: 27:14

Just opening and closing your eyelids in the dark?

Speaker 2: 27:16

Yes. And the researchers observed a phenomenon they termed stationarity.

Speaker 1: 27:21

Stationarity.

Speaker 2: 27:22

When a subject shifted states, for example, and they first closed their eyes, the photon count would become highly variable and chaotic for a period of time. But as the two-minute wind progressed, The emission rate would settle into a stable stationary baseline.

Speaker 1: 27:36

Oh, I see. It's like dropping a rock into a pond. At first, you get all these chaotic ripples, but eventually the surface smooths out and it finds a new equilibrium.

Speaker 2: 27:45

That's exactly it. What is remarkable, though, is that the final stationary baseline was fundamentally different depending on the task. The stable light count when the subject's eyes were open was measurably different from the stable light count when their eyes were closed.

Speaker 1: 27:59

Okay, you really have to think about the physical reality of that for a second. The room is in absolute total darkness. Whether your eyelids are open or closed, zero visible light is hitting your retina. There is no external sensory input changing whatsoever. But the mere physical act of closing your eyelids alters the internal cognitive state of your brain.

Speaker 2: 28:20

Right. Because from a neurobiological perspective, closing your eyes initiates a massive shift in your brain networks. The visual cortex basically stops anticipating active input. And the brain often shifts into what is known as the default mode network, which is associated with internal reflection, daydreaming, resting states.

Speaker 1: 28:40

And that internal software update, that shift in networks, alters the metabolic burn rate of the neurons, which in turn literally changes the exact amount of light leaking through your skull.

Speaker 2: 28:49

It's astounding. It proves that biophotons are deeply, physically tethered to our cognitive states, which led the researchers to the next logical experiment.

Speaker 1: 28:58

Right. If merely opening and closing your eyes changes the light, What happens when we actively introduce a real stimulus? And more importantly, how does this glowing metabolic light relate to the electrical brain waves we have already been studying for like a century?

Speaker 2: 29:12

To find out, they wired the subjects up with an EEG cap, electroencephalography. They placed electrodes all over the scalp to measure the microvolt electrical fluctuations the brain waves simultaneously with the PMTs measuring the light.

Speaker 1: 29:24

So they're tracking electricity and light at the exact same time.

Speaker 2: 29:27

Yes. They needed to find the bridge between the electrical language and the metabolic language of the brain. So they introduced a very simple auditory stimulus. The sound of a wood block played at exactly 120 beats per minute.

Speaker 1: 29:39

At just two clicks per second.

Speaker 2: 29:41

Right. But they only played it into the right ear of the subject.

Speaker 1: 29:44

Okay. Why? Just the right ear?

Speaker 2: 29:46

Because we know from established neuroscience that auditory processing is highly lateralized. A sound presented to the right ear is primarily processed by the left temporal lobe. the researchers monitored the high-frequency electrical rhythms during this, specifically the beta-2 spectral power densities.

Speaker 1: 30:03

Okay, let's clarify what beta-2 waves are for a second. Beta waves generally represent a state of active alert concentration. If you are solving a hard math problem or actively listening to a rhythmic beat, your brain produces beta waves. And spectral power density just refers to how intense or strong that specific frequency band is at a given moment.

Speaker 2: 30:24

Exactly. So as expected, when the wood block played in the right ear, they saw a distinct shift in the electrical beta 2 rhythms over the left temporal lobe. But what's fascinating here is looking at the light data. They found that the electrical rhythms over the temporal lobe during the auditory stimulus correlated specifically with the UPE light counts coming from the occipital lobe.

Speaker 1: 30:45

Wait, wait. Why would hearing a wood block change the light coming from the part of the brain that processes vision? The occipital lobe is all the way at the back of the head. Why is the visual center responding to a sound in total darkness?

Speaker 2: 30:58

This touches on the concept of cross-modal neural processing.

Speaker 1: 31:02

Cross-modal, meaning crossing senses.

Speaker 2: 31:04

Right. The brain does not operate in perfectly isolated silos. When you introduce a strong rhythmic auditory stimulus, it demands cognitive attention. That level of arousal and active processing can actually trigger changes in regional cerebral blood flow and metabolic activity across wide swaths of the cortex, including the visual areas, even in the complete absence of light. It could be an anticipatory response. The brain hears a rhythmic sound and the visual cortex boots up, basically expecting to see the source of the rhythm. That sudden shift in metabolic demand in the iscipital lobe generates a corresponding shift in oxidative stress, and therefore a shift in photon emission.

Speaker 1: 31:44

That is just incredible. But looking at the data, there's a massive temporal puzzle here that totally blows my mind. When you look at an EEG reading on a screen, electrical brainwaves are incredibly fast. A neuron fires, and the electrical wave spikes in literal milliseconds. But this metabolic light operates on, like, a geological timescale by comparison.

Speaker 2: 32:05

Yes, remember, it took up to two minutes for the UPEs to reach stationarity after a task change, and the overall rhythm of the light was cycling at under 1 hertz.

Speaker 1: 32:14

It's like trying to compare the speed of a fiberoptic text message to the slow changing of the ocean tides. How can two things that operate at such vastly different speeds be correlated?

Speaker 2: 32:24

Because they are two different manifestations of the exact same underlying event. The electrical signaling is immediate. It is the command. The oxidative metabolism is gradual. It is the logistical supply chain fulfilling that command.

Speaker 1: 32:38

Oh, I like that.

Speaker 2: 32:38

Right. When a region of the brain becomes electrically active, it rapidly consumes its immediate ATP energy stores. To replenish them, the mitochondria have to ramp up oxidative phosphorylation. That process takes time. The reactive oxygen species build up over seconds and minutes, and the light emission basically trails the electrical activity like a slow metabolic shadow.

Speaker 1: 33:00

A metabolic shadow.

Speaker 2: 33:02

By correlating the EEG with the PMT data, the scientists are basically acting as cryptographers, translating between the fast electrical language of thought and the slow glowing metabolic language of sustenance.

Speaker 1: 33:13

So zooming out for a second, what does all this actually mean for us? We've covered wet bonfires, the sheer impossibility of a quantum internet in our heads, and people sitting in pitch black rooms listening to wood blocks. Why is it important that scientists can measure this faint glow?

Speaker 2: 33:27

Because it represents the birth of an entirely new non-invasive diagnostic field, photoencephalography.

Speaker 1: 33:35

Think about the tools we currently use to look inside the human brain. If you go to a neurologist today, they might order an fMRI. You are shoved into this loud claustrophobic tube that uses magnetic fields so powerful they can literally rip a chair across the room just to measure blood oxygen levels.

Speaker 2: 33:53

Or they might use a PT scan, positron emission tomography.

Speaker 1: 33:56

Right.

Speaker 2: 33:56

That requires a doctor to literally inject a radioactive isotope, a tracer, into your bloodstream so they can track exactly where your brain is actively burning glucose. Now, these are incredibly powerful tools, obviously, but they are massively expensive, functionally restrictive. And in the case of P-scans, they expose the patient to ionizing radiation.

Speaker 1: 34:15

Which you generally want to avoid if you can.

Speaker 2: 34:17

Exactly. Photoencephalography offers a completely passive alternative. You don't need giant magnets, and you certainly don't need to inject radioactive sugar into anyone. The patient simply sits comfortably in a dark room, and highly sensitive cameras measure the natural light already leaking out of their skull. It is the ultimate non-invasive window into the brain.

Speaker 1: 34:38

And because this ultra-weak light is a direct byproduct of oxidative stress and metabolic rate, it feels like it could serve as a revolutionary early warning system for pathology. Because when a neurological disease begins, cellular metabolism is often the very first thing to malfunction, right? Years before gross structural damage is visible on an MRI.

Speaker 2: 34:59

That's exactly the promise here. Take cancer, for example. Tumor cells have wildly different, highly accelerated metabolic rates compared to healthy tissue. A photoencephalogram could potentially detect the altered light signature of a budding glioblastoma simply by reading the abnormal photon emissions through the scalp long before it's a massive mass.

Speaker 1: 35:18

Wow. Or consider a mild traumatic brain injury, like a concussion. An x-ray or a standard CT scan will often show absolutely nothing because there is no bleeding or obvious skull fracture. But the brain tissue has suffered microscopic shearing and intense oxidative stress.

Speaker 2: 35:36

Right, and that lingering metabolic disruption would theoretically produce a distinct UPE signature. Perhaps most consequentially, this could be used for neurodegenerative diseases.

Speaker 1: 35:46

Like Alzheimer's.

Speaker 2: 35:47

Yes, conditions like Alzheimer's are characterized by severe mitochondrial dysfunction and radical oxidative stress long before memory loss becomes apparent. We could potentially screen for the early metabolic markers of dementia simply by analyzing the subtle glow of a patient's mind.

Speaker 1: 36:02

It is like a mechanic being able to diagnose a failing engine purely by analyzing the exact chemical composition and color of the exhaust fumes. It's a completely new vector for understanding the health of our neurons.

Speaker 2: 36:13

It is a profound medical frontier. But as we reach the end of our deep dive today, there is one final concept buried in the literature that pushes this entire phenomenon past biology and into almost cosmic territory.

Speaker 1: 36:24

I know exactly the detail you were talking about, and it is the perfect way to wrap this up. The magnetic field connection.

Speaker 2: 36:30

Yes. The researchers of the iScience paper note a fascinating finding from previous neurological studies regarding human alpha brainwaves. Now, alpha rhythms, which hover around 8 to 12 hertz, are the smooth, synchronous electrical waves your brain produces when you are relaxed, resting, usually with your eyes closed.

Speaker 1: 36:50

Right, the chill waves.

Speaker 2: 36:52

Previous research has actually demonstrated that human alpha rhythms correlate in real time with fluctuations in the Earth's ambient magnetic fields.

Speaker 1: 37:00

Just let that sink in for a second. The electrical pulsing of your brain as you relax is actively dancing in time with the magnetic field of the planet itself.

Speaker 2: 37:08

Yeah, it's wild. And building on that, during the eyes-closed tasks in the darkroom, the researchers found that both the ambient background photons in the room and the bio-photons emitting from the brain varied systematically with those alpha rhythms.

Speaker 1: 37:22

Which leads to this absolutely mind-bending speculation. Our brains are constantly emitting this ultra-weak electromagnetic light. And the electrical rhythms that dictate the intensity of that light are being subtly, imperceptibly influenced by the massive electromagnetic fields of the Earth.

Speaker 2: 37:39

It really makes you wonder, are our minds far more physically tethered to the ambient fields of the surrounding universe than we ever realized? Are we participating in a subtle electromagnetic exchange with the planet every single second of our lives?

Speaker 1: 37:54

It completely reframes our relationship with our environment, doesn't it?

Speaker 2: 37:58

It absolutely does.

Speaker 1: 37:59

I mean, we started this deep dive talking about total isolation, sitting in a pitch black sensory deprivation room, feeling completely cut off from the rest of the universe. But the science shows us that is an illusion.

Speaker 2: 38:10

A complete illusion.

Speaker 1: 38:12

Even in the darkest, quietest void you can possibly imagine, your brain is burning like a microscopic bonfire. It is projecting its own light into the dark and its electrical rhythms are quietly humming along to the electromagnetic heartbeat of the earth. You are never truly in the dark and you are never truly disconnected. It's a beautiful piece of biology for you to ponder the next time you find yourself sitting alone in a pitch black room.

Speaker 2: 38:37

Heliox is produced by Michelle Bruecker and Scott Bleakley. It features reviews of emerging research and ideas from leading thinkers curated under their creative direction with AI assistance for voice, imagery and composition. Systemic voices and illustrative images of people are representative tools, not depictions of specific individuals. Thanks for listening today. Four recurring narratives underlie every episode. Boundary dissolution, adaptive complexity, embodied knowledge, and quantum-like uncertainty. These aren't just philosophical musings, but frameworks for understanding our modern world. We hope you continue exploring our other episodes, responding to the content, and checking out our related articles at helioxpodcast.substack.com.