A tiny array of microelectrodes, shown here, was implanted into the brains of epilepsy patients,
allowing scientists to gather data about seizures at the level of single cells.
For the first time, scientists have recorded activity from hundreds of single cells in the human brain during a seizure. The research, published this week in Nature Neuroscience, is part of a growing movement to employ new technologies to study brain processes at the single-cell level, which until recently has been impossible to do in living humans.
In an epileptic seizure, the normally orderly activity of neurons goes haywire. The abnormal amounts of electricity that get discharged can be temporarily disabling. Scientists typically monitor human seizures using electroencephalogram (EEG), which measures electrical activity across millions of neurons at a time, an approach that has revealed much about the overall patterns of activity in seizures. But researchers hope that by studying single cells, they’ll learn how seizures spread…
The study, part of a longstanding collaboration between researchers at Brown University and Massachusetts General Hospital, examined four patients who were already undergoing a procedure to study the origins of their seizures. All of them had uncontrolled focal epilepsy, in which the seizures originate in a specific part of the brain.
In addition to fitting the patients with normal EEG electrodes, surgeons implanted a four-millimeter-square microelectrode array at the suspected origin of the seizures. The implant allowed them to record the activity of hundreds of individual neurons over the course of several days, during which patients experienced multiple seizures.