Nestled in the core of the brain is the hippocampus, a little curve of tissue central to memory and learning . It serves as a processing center for our experiences, helping organize information as it comes in. The hippocampus does that when we’re awake—and, a new study suggests , even when we’re unconscious.

The small study, published recently in the journal Nature , drew on data from seven people who had surgery to remove portions of their brains as a treatment for epilepsy . It found surprising evidence that under general anesthesia , the hippocampus is still performing some of the language-processing tasks it does in the conscious brain.…