Once adult lab mice learn to associate a particular stimulus--a sound, a flash of light--with the pain of an electric shock, they don't easily forget it, even when researchers stop the shocks. But a new study in the December 23 issue of Science shows that the antidepressant Prozac (fluoxetine) gives mice the youthful brain plasticity they need to learn that a once-threatening stimulus is now benign.
Read More »