Researchers Tweak Mouse Neurons To Activate Specific Memories

An anonymous reader writes "According to new study published in Nature (abstract), MIT researchers have figured out how to trigger specific memories in rats by hitting certain neurons with a pulse of light. From the article: 'The researchers first identified a specific set of brain cells in the hippocampus that were active only when a mouse was learning about a new environment. They determined which genes were activated in those cells, and coupled them with the gene for channelrhodopsin-2 (ChR2), a light-activated protein used in optogenetics. ... The light-activated protein would only be expressed in the neurons involved in experiential learning — an ingenious way to allow for labeling of the physical network of neurons associated with a specific memory engram for a specific experience. Finally, the mice entered an environment and, after a few minutes of exploration, received a mild foot shock, learning to fear the particular environment in which the shock occurred. The brain cells activated during this fear conditioning became tagged with ChR2. Later, when exposed to triggering pulses of light in a completely different environment, the neurons involved in the fear memory switched on — and the mice quickly entered a defensive, immobile crouch.'"

Comments

Total recall

[Reverand Dave]

Next up, a vacation without without going anywhere!

Re:Total recall

[g0bshiTe]

I'm confused, is it mice or rats? Or do these scientists not know the difference.

Re:Total recall

[Samantha Wright]

It's mice. The unawareness is restricted to the editor and/or submitter. You may find this pattern familiar.

Re:Fascinating

[Ihmhi]

Think of the defense applications!

An angry group of foreign citizens have surrounded the American Embassy in Egypt. All hope is lost. Suddenly, a flash of light from the roof - and everyone falls over vomiting and crying as they think about that one time they saw their parents fucking.

Re:poor reasoning

[b4dc0d3r]

Luckily, you're dealing with Science, not armchair philosophers or youtube commentators. I appreciate your attempt at using logic, but don't trust the summary to explain everything. From the abstract, it seems Science has considered that you might have a point, and went back in time to address it.

The mice showed increased freezing only upon light stimulation, indicating light-induced fear memory recall. This freezing was not detected in non-fear-conditioned mice expressing ChR2 in a similar proportion of cells, nor in fear-conditioned mice with cells labelled by enhanced yellow fluorescent protein instead of ChR2. Finally, activation of cells labelled in a context not associated with fear did not evoke freezing in mice that were previously fear conditioned in a different context, suggesting that light-induced fear memory recall is context specific. Together, our findings indicate that activating a sparse but specific ensemble of hippocampal neurons that contribute to a memory engram is sufficient for the recall of that memory