Around 40% of epilepsy patients fail to respond to anticonvulsant medications, some can be treated with surgery targeting the part of the brain that triggers seizures which is not always effective. Stopping seizures at their source may provide a more effective way to treat medication-resistant epilepsy. An electronic device that’s smaller than a playing card and implanted into the skull could help epilepsy patients who don’t respond to medication. Electrodes from the stimulator extend into the brain, targeting the area where seizures originate. The electrodes detect abnormal brain activity and attempt to shock it away before it spreads.

The device, known as the responsive neurostimulation system is just one of a growing number of electrically based devices in development or already on the market.
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