Time reports:

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. When doctors played episodes of a podcast in the operating room, neurons in the hippocampus seemed to be anticipating the next words in a sentence and processing information about parts of speech.

It’s further proof that even fairly complex neural processes are not the same as consciousness.

The study was inspired by earlier work on the concept of memory formation during anesthesia, says Dr. Sameer Sheth, a professor of neurosurgery at Baylor College of Medicine and an author of the new paper. There is some evidence that while surgical patients will not remember, on waking, a list of words doctors played for them in the operating room, there might still be some traces left by the experience. “Given a list of words, they’re more likely to pick the ones that were presented to them while asleep, versus not,” Sheth says. [Continue reading…]