What is functional neurological disorder?
Functional Neurological Disorder, or FND, often feels like a medical mystery novel—full of strange symptoms but without the big “aha!” moment of a clear diagnosis on a scan. Here’s the plot twist: with FND, the hardware of your brain is perfectly intact, but the software—the signals and communication pathways—gets scrambled. It’s as if your body is running on “glitch mode,” producing real symptoms without a visible problem on MRI or blood tests. If you’ve ever wished you could reboot your system, you’re not alone.
Living with FND can mean life is full of unwelcome surprises. One week you might notice your legs feel weak or trembly. Another day, it’s your speech that stumbles, or vision and memory start playing tricks. Adding to the confusion, these episodes can look like seizures or strokes—but typical tests come back clear. No wonder patients and their families often feel like they’re lost without a map. What’s important to know is that these symptoms are absolutely real, and you’re not imagining things.
So what’s really going on in the brain? This is where science steps in, flashlight in hand. Functional MRI (fMRI) and EEGs have shown that, in FND, brain circuits involving movement, sensation, and control “fall out of sync.” Think of your neurons as members of a symphony: in FND, they still show up for practice, but the conductor’s signals are jumbled. The result is discord—not disease. These scans don’t show missing notes or damaged instruments, but they do reveal poor coordination behind the scenes. I also like to think of it as a software problem when the hardware is fully intact. Ever had to restart your computer because a program was glitchy? Smart phone giving you problems? What happens when you power cycle these tools? Everything is running smoothly again, and you don’t need a new laptop or iPhone.
Because we are used to the effectiveness of a quick reboot, it’s natural to want a quick fix for your head—maybe a pill or a procedure borrowed from epilepsy, stroke, or Lyme disease. But here lies a critical takeaway: medications aimed at these other illnesses simply do not work for FND. Worse yet, they can bring toxic side effects and pile new problems onto your plate. FND is not caused by infection, inflammation, or physical brain injury, so it makes sense that antibiotics or anti-seizure drugs won’t help.
Instead, hope comes from an unexpected direction: behavioral therapies. Cognitive behavioral therapy (CBT), physical therapy, and occupational therapies have all shown real success. These approaches retrain your brain step by step, encouraging healthier pathways to take root. Sometimes, someone who arrived to therapy in a wheelchair finds themselves walking out. That’s not wishful thinking—it’s evidence-backed medicine, and it’s changing lives.
The key to recovery is partnership. If you don’t buy into FND, you certainly won’t be able to navigate your way out of it. When patients and medical teams are on the same page, and everyone understands what FND is (and isn’t), progress can be remarkable. Clarity, trust, and early intervention form the foundation for real improvement. And when family and friends get involved, the support network becomes a powerful tool for healing.
When my oldest daughter was 3, she began to complain of pain in her left eye. Always the left. And it was affecting her vision. She kept squinting, rubbing her eye, and when she told us she had trouble seeing, my heart sank. Being a physician, I had a general understanding of the range of possibilities. A mild scratch on the cornea, a tumor in the brain. I let my mind run with all the eventualities. We were able to see the eye doctor pretty quickly who couldn’t figure it out, and finally got an appointment with a neuro-ophthalmologist (one of those subspecialized neurologists who know everything about the nerves and muscles in the eye). After some sophisticated examination techniques in the clinic, lens testing, and whatever else they did, he stepped out with me and started the talk. “Sometimes, kids feel like there is something in their eye…or they can’t see….” etc etc “…but it’s really just, in their head.” BOY WAS I RELIEVED! My own daughter had FND.
I see patients with FND in my practice all the time, so I felt comfortable with this. I bought into it. I was confident in the doctor’s confidence.. And after a few more weeks of consoling my daughter through her weird eye stuff, my heart returned to its normal rate, and the the problem went away.
If you’re facing FND, it’s easy to feel discouraged—especially in the early days. But diagnosis is not destiny. With understanding, the right therapy, a strong relationship with your physician built on mutual trust, and the patience to let your brain relearn its rhythm, people do get better. You can regain independence, function, and a sense of control that may have felt lost.
So, while FND might misfire your brain’s electrical symphony, it’s not a life sentence. Science is shining a light through the maze, behavioral therapy offers a working compass, and countless people are finding their way back to themselves, one steady step at a time.