Memories have always been one of the most mysterious functions of our brain.
A recent discovery showed that moments before a memory is about to emerge, certain nerve cells jolt into action. Electrodes were implanted into the brains of epilepsy patients suddenly picked up signals in the hippocampus, a central memory center in the brain, while patients were shown pictures of things familiar to them. While the patients were viewing the images, the electrodes detected brain activity in the form of sharp-wave ripples.
Researchers later blindfolded the same patients and asked them to remember the pictures they were shown. A few seconds before they began to describe the pictures, the researchers noticed activity in the sharp-wave ripples, which resembled the ripples seen while showing them the pictures.
Since the ripples were echoed, we’ve learned that the ripples are essential in learning new information and recalling that information at a later time. It was already known that the ripples in the hippocampus were important in the formation of memories, but their role in recalling the memories was not clear.