According to USNews, lead author Sadegh Nabavi said, "We can cause an animal to have fear and then not have fear and then to have fear again by stimulating the nerves at frequencies that strengthen or weaken the synapses."
Most reports are focusing on the applications of the technique to Alzheimer's and brain injuries, as a method of restoring lost or broken memories. While there are problems with the practicality of potential application for memory restoration in humans - for example, the rats had surgically implanted optogenetic machinery in their brains and holes drilled through the skulls, allowing for cables to travel - it is possible that using this technique to eliminate memories could be just as important.
I first encountered the idea of the biological importance of forgetting when reading Michael Pollan's The Botany of Desire, specifically the portion on Cannabis. While it's not a novel revelation, it is still intriguing to consider that forgetting is important. Forgetting allows us to make room for new memories, and perhaps more importantly, to be able to use more accurate information to make good decisions. Haven't we all made decisions, only to later find out we were working with bad information?
In 2007, researchers at Stanford showed that when a particular memory is retrieved, it becomes "weighted" as more important. As a result, the non-important memories are weakened. I can't help but wonder if a valid application of Nabavi's work could be targeting less-important information for forgetting, allowing the already existing good stuff to dominate.
We live in a world of constant documentation. We are facebook friends with past roommates' siblings, guys that played in a band we saw once, and exes of our exes. Relationships we used to just let fade away over time now are suspended in a state of perma-limbo, ready to be revived at any time. Every photo we take is cataloged permanently. All of this makes me wonder if we are messing with our own natural capability to forget, by reversing the culture, making everything rememberable and nothing forgettable.