10/3 Ramirez

Both Ramirez et al papers for this week involved optogenetically reactivating dentate gyrus cells, and both discussed several innovative and fascinating experiments to show what manipulating the hippocampus can do to downstream targets and behavior. Ramirez et all (2015) discussed how activating positive memory engrams suppresses depression-like behavior, which I found especially interesting because the past weeks have shown different mechanisms that suppress depression. All of these experiments are of equal importance because the mechanisms of depression are so complex and so many people are affected by it. Thus, the more experiments devoted to studying depression, the better. Targeting specific brain areas and/or cells, like in the second paper, is a step above many current antidepressants that affect the entire brain, and can lead to reduced side effects and greater efficacy.

Ramirez et al (2013), who “created a false memory in the hippocampus,” got me thinking to whether or not the researchers had actually created a false memory. While I thought the experiment itself was remarkable, and the results can be very important for future research, I asked myself if it was truly a false memory? Although the mice did freeze in a completely different context than where they got shocked (chambers A and B were very different in design), I don’t know if “false” is the most accurate word because the mice remembered they got shocked, which was a real memory. It’s just the context that was different. An example of what a real “false” memory could be is if the mouse was never shocked to begin with, and the researchers somehow manipulated their brains to make them think they got shocked. So, it was definitely a manipulated and artificial memory, but I am not sure that I would exactly call it a false memory.