Scientists can now revive lost memories in mice

An amazing new experiment has shown that it’s not only possible to revive a memory that has been forgotten, but that our brains may not actually get rid of information once we forget it. According to the Washington Post, researchers were able to bring back memories in mice by shining blue light on specific parts of the brain.

The study was published this Thursday in the journal Science, and it described how researchers manipulated the mice’s brains to artificially create, erase, and restore a memory. They used blue light and a jolt of electricity to get the fascinating experiment started.

After identifying the neurons associated with making memories, the scientists introduced a special protein via a virus into the mice’s brain, making the cells sensitive to blue light. When the light was shining, the brain cells became active and were capable of making memories.

The researchers gave the mice something they surely wouldn’t forget – a small electric shock administered in the same place each time. They found the neurons that were stimulated once the mice returned to the location where they had been shocked – the mice froze up and exhibited fear when they remembered a shock might be coming. They made these neurons sensitive to light using the special protein, so that they would be able to switch the mice’s memory center on and off.

The scientists then gave the mice artificial amnesia by injecting them with a chemical called anisomycin, which hinders memory formation. The mice forgot about the shocks, and walked to the same location exhibiting no fear.

When researchers shined blue light on the neurons they identified and sensitized, the mice’s memory centers “woke up” and they once again feared the location where they had received shocks earlier.

The study presents a fascinating take on the way our brains form memories, and opens the door to further studies about how we can address memory loss. The method outlined in the study won’t be used with humans anytime soon, but the findings suggest that there may be a way to awaken lost memories even after they’re gone.