Machine-learning software is being used to prod an individual’s brain into remembering things.

Backstory: Electrical stimulation to improve brain performance isn’t a new idea—but knowing how to deliver the pulses is tough.

First, learn: Researchers from University of Pennsylvania gathered data from 25 epilepsy patients, each with up to 200 electrodes already implanted in their brains for monitoring purposes, while they performed memory tasks. That formed a training set for AI to learn personalized models about how brain activity relates to remembering something.

Then, do: The same electrodes were then used for stimulation. The researchers had patients perform memory tasks while using the AI to plan stimulation when it thought they might forget something. It worked: patients with AI stimulation performed 15 percent better than controls on word-recall tasks.

Why it matters: Human understanding of the brain remains limited. The approach may help build systems to improve brain function, even if precise understanding of how memory works eludes us.