An Injection Straight to the Brain Makes Rats Forget Their Fears
Just about everyone can think of some memory he or she would rather forget. For some, it's something like a relationship gone wrong, or high school. For others -- like soldiers returning from war zones -- those bad memories can be highly disruptive, impeding the ability to live a normal life. But Puerto Rican researchers may have found a way to reduce the fear associated with our memories by injecting a naturally occurring chemical directly into the brain, replacing anxiety with feelings of security. This isn't the stuff of sci-fi; the procedure doesn't pave over miserable memories with better, different ones. It works by chemically mimicking what's known in the lab as extinction learning. For instance: Researchers can instill a learned fear in lab rats in a Pavlovian fashion, sounding a certain tone while applying a light shock to the rats. After a while, rats learn to fear the pain associated...