Erase a Single Memory!

Joseph LeDoux and his team of scientists at New York University, claim to be able to erase a single memory. The first phase of the experiment included LeDoux's team of researchers teaching rats to fear beeps and sirens by giving them an electrical shock every time the tones sounded. Although this technique has been used several times in the past, nobody ever thought of conditioning for a single memory to be erased from the mind.

Operant conditioning as it is called, uses reinforcement to learn behaviors. There are three types of scenarios which include positive reinforcement, negative reinforcement, and punishment where you no longer want the behavior. In the case of these rats, they are being given a negative reinforcement to associate the shocks with the tones.

After shocking the rats, LeDoux gave half of his experimental rats a drug called U0126, which has been acknowledged to interfere with memory storage. Then he replayed the tones without shocking the rats. As LeDoux played back the tones to the rats the next day, he discovered that rats that had been given the memory blocking drug weren't afraid of the beeps, whereas the rats that did not receive the treatment of U0126 were still fearful of the sounds.

It is believed that U0126 may block the creation of proteins that support the strengthening of connections between neurons. Blocking this connection helps for the amnesiac effect that the rats experience, essentially obstructing memory. The window of opportunity is small though, as it is only possible to erase the memory when it is being retrieved. LeDoux says that "Only those memories that are activated are vulnerable" because that's when the memory is being updated and stabilized again for long-term memory storage.