What Flatworms Taught Me About Memory and Your Phone
A new study shows electromagnetic fields block learning in simple organisms—at exposure levels thousands of times weaker than your devices
I've been reading a study all week that I can't stop thinking about.
Researchers took flatworms—planaria, the kind you might remember from high school biology—and taught them to avoid bright light in a simple maze. The control group learned. They got better at it over several days, choosing the dark arm of the T-maze more consistently. Standard learning behavior.
The worms exposed to electromagnetic fields? They learned nothing. Zero behavioral change. The EMF completely blocked their ability to form new memories.
Here's the part that got my attention: the field strength was only 1 microtesla. That's thousands of times weaker than what your smartphone produces when you're on a call.
What the Researchers Found
The study, published in Bioelectromagnetics in 2025 by Ghassemkhani and Dotta, used theta burst patterned electromagnetic fields—five pulsed bursts at 100 Hz with alternating amplitudes. They exposed planaria to an aversive stimulus (bright light) in a T-maze and tracked two things: how long it took the worms to choose an arm, and which arm they preferred over several days.
The control worms showed a significant decrease in preferred arm selections (p < 0.001). They learned to avoid the bright light. Classic fear conditioning.
The worms exposed to theta burst EMF—either before or after the light exposure phase—showed no change in arm selection. Their behavior remained stable across all testing days. No learning occurred.
The researchers concluded that theta burst electromagnetic fields disrupt the processes involved in fear-related learning, likely by interfering with theta rhythm-dependent mechanisms that are crucial for memory encoding and retrieval.
Let me put that in plain English. Theta rhythms are brain wave patterns that occur across species—from flatworms to humans—during memory formation. When you're learning something new, consolidating a memory, or retrieving information, your brain produces theta waves. They're fundamental to how biological systems encode experience.
These researchers applied an external electromagnetic field that mimicked that natural rhythm. And it jammed the signal. The worms' internal theta rhythms couldn't function properly, so they couldn't form memories.
Why Flatworms Matter
You might be thinking: okay, but these are worms. What does this have to do with me?
Fair question. Here's why this study matters more than you might think.
First, planaria are a validated model organism for studying basic learning and memory. They have simple nervous systems, which makes them ideal for isolating specific mechanisms. When you see an effect this clear in a simple organism, it tells you something about fundamental biology—the kind that scales across species.
Second, the exposure level was remarkably low. One microtesla. For context, a typical smartphone produces fields in the range of 10-1,000 microtesla during active use, depending on distance and signal strength. The worms lost their ability to learn at a fraction of what you're exposed to daily.
Third—and this is the part nobody's talking about—theta rhythms aren't unique to flatworms. They're conserved across evolution. Your brain produces theta waves when you're learning, when you're sleeping, when you're forming new memories. The mechanism these researchers disrupted in worms is the same mechanism your brain uses.
I'm not saying this study proves EMF exposure destroys human memory. That would be an overreach. But I am saying this: if electromagnetic fields can completely block memory formation in an organism with theta-dependent learning, we should be asking harder questions about what chronic exposure does to developing brains.
The Bigger Picture
This isn't an isolated finding. The SYB Research Hub now contains over 1,000 peer-reviewed studies documenting biological effects from non-ionizing radiation. The evidence spans decades, thousands of researchers, and consistent findings across different exposure types and biological endpoints.
What strikes me about this particular study is how clean the result is. No learning. Not "slightly impaired learning" or "statistically significant but small effect." The EMF-exposed worms showed zero behavioral adaptation. That's a complete functional disruption.
Here's My Take
I wrote about early EMF research in Empowered—how in 1924, U.S. Public Health Service surgeon J.W. Schereschewsky exposed mice to high-frequency EMF from vacuum tube oscillators and documented severe physiological effects, including death. That was over a century ago. We've known since then that artificial electromagnetic fields affect living organisms.
What's changed isn't the science. It's the exposure. In Schereschewsky's time, EMF exposure was limited to people working directly with electronic equipment. Today, it's ubiquitous. Chronic. Inescapable for most people.
This flatworm study adds another data point to a pattern we've been documenting for a hundred years: electromagnetic fields interfere with biological processes at the cellular level. Memory formation. Sleep architecture. Hormone production. Cellular signaling. The list goes on.
The fact that such weak fields—1 microtesla—could completely block learning in these organisms should make us question what similar exposures might be doing to children who use devices daily. To students trying to study with WiFi routers three feet from their desks. To anyone sleeping next to a phone on a nightstand.
I think this study matters because it isolates a specific mechanism. It's not vague "EMF is bad" hand-waving. It's precise: theta burst electromagnetic fields disrupt theta rhythm-dependent learning. That's a testable, reproducible finding with clear biological plausibility.
And it should concern us.
What This Means for You
The honest answer: we don't know exactly how this translates to human exposure. But here's what we do know, and what you can do about it.
Distance is your friend. EMF intensity drops exponentially with distance. If the worms lost learning ability at 1 microtesla, and your phone produces 100-1,000 times that at close range, moving the phone even a few inches away dramatically reduces exposure. Don't sleep with it on your nightstand. Don't carry it in your pocket all day. Use speakerphone or earbuds instead of holding it to your head.
Reduce chronic exposure during critical windows. Memory consolidation happens during sleep. Learning happens when kids are studying. These are high-stakes cognitive processes. Turn off WiFi at night. Keep devices out of bedrooms. Create low-EMF zones during homework time. You don't need to eliminate exposure entirely—just reduce it when it matters most.
Pay attention to developing brains. Children's nervous systems are still forming. Their skulls are thinner. Their cells are dividing more rapidly. If theta rhythms are essential for learning—and they are—and if EMF disrupts theta rhythms—which this study suggests—then chronic exposure during development is the highest-risk scenario. Limit device use for young children. It's not about being perfect; it's about being thoughtful.
Wired beats wireless. Ethernet cables, wired headphones, corded landlines—these aren't just nostalgic. They're functional alternatives that eliminate pulsed EMF exposure. You don't have to go full Luddite, but when wired options are easy (home office setup, bedside alarm clock), use them.
Trust your instincts. If you notice brain fog, poor sleep, difficulty concentrating, or memory issues that correlate with device use, that's data. Your body is telling you something. The science supports what many people already feel intuitively: something about this technology isn't sitting right with our biology.
What do you think? Does this study change how you think about device use? Hit reply—I read every response.