A new study suggests that receiving an electrical shock to the brain shortly after recalling a troubling event can help a person forget many of the upsetting details. The study is to show that memories are plastic. That means they can be changed and sometimes even erased altogether. These findings could one day lead to new treatments for people who suffer from mental diseases like severe anxiety or post-traumatic stress disorder. Such treatments may be able to target severely disturbing memories and help patients forget them.

Forty-two people took part in the new study. All had severe depression. This disease leaves people feeling sad and hopeless, and they often lose interest in activities they once enjoyed. Doctors were already treating these study participants with electroconvulsive therapy, or ECT. It delivers an electrical jolt to the brain.

Scientists knew ECT can muddle a patients memory. But the new study shows a way to turn that side effect into a benefit. Doctors found they could target which details were forgotten by timing the treatment to occur shortly after those details had been recalled.

Each patient taking part in the study listened to two upsetting stories while looking at a series of pictures. In one story, a boy was hit by a car, doctors had to amputate both of his feet later. In the second, a woman was attacked in an alley. One week after first hearing both stories, each patient looked at a photo from one of the events. Doctors then asked questions that forced the patients to remember details about that event. Neuroscientists have found evidence that recalling a story in such a way can make memories about it vulnerable to change.

And thats precisely what the researchers attempted to do. They looked to change that recalled memory with ECT.

Immediately after patients recalled details of one story, the doctors put them to sleep. While they were unconscious, most patients received an ECT shock to the brain. One day later, each patient took a multiple-choice test. They had to remember details about both upsetting stories.

People who did not get ECT remembered details of both stories fairly well. Patients whose brains were zapped as part of the treatment remembered details of only one story well. It was the one they had not been thinking about just before the treatment.

Details of the story the patients had been thinking about before ECT were recalled poorly, the scientists found. In fact, the patients scored no better on remembering these details than if they had simply guessed the answers.

1. What is the probable clinical implication of the research? ____.

A. It could be applied to amputation

B. It could be used to treat mental diseases caused by severe anxiety or post-traumatic stress disorder

C. It could be used to treat loss of memory

D. It could be applied to organ transplant

2. What are NOT the symptoms of depression? ____.

A. feeling sad B. feeling hopeless

C. loss of appetite D. loss of interest in hobbies

3. What does the last sentence imply? ____.

A. The patients could not remember these details well

B. The patients could guess the answers

C. The patients could remember these details as well as they could guess the answers

D. The patients couldnt guess the answers but they could remember these details