How to erase a memory -- and restore it

(University of California - San Diego) Researchers at the University of California, San Diego School of Medicine have erased and reactivated memories in rats, profoundly altering the animals' reaction to past events. The study is the first to show the ability to selectively remove a memory and predictably reactivate it by stimulating nerves in the brain at frequencies that are known to weaken and strengthen the connections between nerve cells, called synapses.