You cannot change your past, but what if you could alter the way you remember it? What if you could even delete some memories entirely? Many people who have suffered from post-traumatic stress disorder seek psychological help to do just that. In North America, scientists are going further, looking for ways to alter memories neurochemically.
Recent studies at McGill and Harvard universities have used propranolol, a drug that is normally used to treat heart disease, to help people who have suffered a trauma. They found that those who took the drug during a period of ”controlled recall” showed fewer signs of stress the next time they were asked to remember the event. The researchers suggest that the drug may have helped ”dampen” the memories — that is, removed their ability to cause distress.
This is what most clinicians who work with trauma victims try to do. They do not discourage people from remembering what happened but they help them learn to tolerate the pain. We know that once patients can do this, they can move on. However, I am less convinced that someone will move on if he simply cannot remember what happened. The human brain is designed to explain and to understand. If there are missing chunks in the memory, I think it will cause more distress than it will relieve.
Even so, at New York University, they appear to be trying to erase memories altogether — in rats, at least. The rats were trained to associate two musical tones with a mild electrical shock; from then on, they would brace themselves when they heard the tone. Then half the rats were given a drug called U0126 while they heard one of the tones. Thereafter, they no longer braced themselves, leading researchers to conclude that U0126 had ”deleted” the memory it targeted.
The connection that has been made between these two studies is worrying. Deleting memories did not help Kate Winslet and Jim Carrey much in Eternal Sunshine of the Spotless Mind. Indeed, would many of us really want gaps in our memories, particularly if others around us could still remember what we no longer could? Because the rats cannot talk to us, we do not know whether they are unable to remember what they learned, or whether they still remember but just cannot react to what they know. So, caution, please. We understand so little about the marvellously complex human brain. — Â