What causes seizures, and how can we treat them? - Christopher E. Gaw

Nearly three millennia ago, a Babylonian tablet described a curious illness called miqtu. Said to cause symptoms ranging from facial twitching to full body convulsions, the Babylonians believed those afflicted were possessed by evil spirits, and the only treatment was divine intervention. Today, we know the symptoms of miqtu by another name, and modern medicine has developed numerous treatments for those experiencing seizures. But these ancient afflictions still hold a surprising number of secrets.

Doctors define a seizure as any set of symptoms resulting from excess electrical activity in the brain. Outside this shared feature, there is a massive range of seizure symptoms, and researchers have identified a variety of different seizure types. But regardless of the underlying conditions that cause them, every seizure begins here. Hippocrates identified the brain as the source of seizures around 400 BCE. However, this insight didn't immediately lead to better treatments.

Generally, ancient Greeks prescribed medicinal herbs and alterations in diet. If they believed the seizure was caused by bleeding in the skull, they sometimes employed a technique called trepanation. This early surgery involved drilling a hole in the skull to let blood escape and relieve pressure on the brain. Trepanation had sizable risks. But it wasn’t until the 19th century that scientists would make the next leap forward in seizure treatment.

In 1870, two German researchers discovered that using electricity to stimulate specific areas of a dog’s brain could move parts of its body. Around the same time, other scientists discovered the brain and nervous system were connected via a network of cells called neurons that transmitted electrical signals throughout the body. This established the brain as the control center for nerve impulses that determine our thoughts and movement. Better yet, this model made it clear that seizures were due to errors in that control center, such as misfiring neurons or excess electrical activity.

Early experiments even suggested that different patterns of misfiring could account for different seizure types and symptoms. So if seizures were due to neurons misfiring, how could doctors stop this from happening? Physicians like Sir Charles Locock hypothesized that sedative drugs might calm overactive brain activity, a theory he confirmed by treating seizures with a medication called potassium bromide. Others like Sir Victor Horsley suspected that removing damaged parts of the brain might stop a patient's seizures.

In 1886, he performed a craniotomy, temporarily removing part of a patient's skull to extract scarred brain tissue. Not only did his patient survive, but his seizures improved, launching further research in surgical treatments. Over the next two centuries, seizure treatments advanced rapidly. And today, there are dozens of available seizure medications that work with unprecedented specificity.

Some newer medications are able to focus on specific proteins in the neuron to help manage electrical activity. And advanced brain imaging techniques can sometimes allow doctors to pinpoint exactly what parts of the brain are causing an individual's seizures. Surgeons then use this information to perform targeted surgeries. These various treatments help doctors manage the majority of seizure cases, allowing most people with seizures to live healthy and comfortable lives.

But the underlying pathology of many seizures remains elusive. In cases without clear brain damage or certain types of pre-existing conditions, it's incredibly difficult to determine what causes neurons to misfire. It's also not always clear why some treatments are effective. And even more mysterious are cases where seizures are resistant to existing treatments that work on similar seizure types.

Scientists are still working on these questions, but there are clear answers for what to do if you encounter someone experiencing a seizure. You should never hold a seizing person down, put objects in their mouth, or perform CPR. Instead, try to keep the person safe from falling or bumping their head, shift them onto their side to keep airways open, and stay with them until medical help arrives.