Lost your car keys? Instead of retracing your steps, you might want to try walking backward to jog your memory. A study published in the January issue of Cognition found that people who walked backward, imagined they were walking backward, or even watched a video simulating backward motion had better recall of past events than those who walked forward or sat still. Why? Thats still something of a mystery, says Dr. Daniel Schacter, the William R. Kenan, Jr., Professor of Psychology in the Department of Psychology at Harvard University. Its possible that people associate going backward with the past and this somehow triggers a memory response. "We know it cant have anything to do with how theyve encoded the information," says Dr. Schacter. After all, people werent walking backward when they stored the memories tested in this study. It may take future studies to shed additional light on the issue. "But I found the results intriguing," says Dr. Schacter. Testing the effects of motion Researchers decided to test the effect of backward movement on memory because numerous past studies have found links between motion and memory. They recruited 114 people to take part in six different memory experiments. In the experiments, they showed participants a video of a staged crime, a word list, or a group of images. They then asked the participants to walk forward, walk backward, sit still, watch a video that simulated forward or backward motion, or imagine walking forward or backward. The participants then answered questions related to the information they saw earlier. In all cases, people who were moving backward, thought about moving backward, or saw a video depicting reverse motion were better able to recall the information they had been shown earlier, compared with those sitting still. In five of the six experiments, memory was better when people moved backward than when they moved forward. On average, the boost in memory lasted for 10 minutes after people stopped moving. In the staged crime experiment, for example, participants watched a video of a woman, sitting in a park, who has her bag stolen. Researchers tested how well people could answer 20 questions about the simulated crime, depending on the direction they moved or if they sat still. They found that people who walked backward were significantly more likely to answer more questions correctly, regardless of how old they were or other factors. The findings suggest that this motion strategy might be a means of helping people better recall past events. Improving memory recall Dr. Schacter says backward motion could one day be added to existing techniques already in use to boost memory. One such method is called a cognitive interview. The interviewing technique helps people to recall details of a recent event, for example, if they witnessed a crime. "What interviewers are trying to do is get as much accurate information as they can without inducing a false memory," says Dr. Schacter. They do this by metaphorically walking the person through the event forward and backward. Its possible that literally walking backward may do something similar in the brain, he says. Using backward motion could potentially augment the cognitive interview or be used as a separate technique, he says. One key question that remains to be answered, however, is whether the technique would promote accurate recall of everyday events, says Dr. Schacter. "Its really too early to say whether there would be practical applications," he says. The study authors said that future research will look to uncover not only why this technique seems to improve memory recall, but also whether motion-based memory aids could help elderly adults or people with dementia. In the meantime, will walking backward help boost your short-term memory? "This study would suggest that there are some circumstances where this might be the case," says Dr. Schacter. "It may be worth trying."(Harvard Health Letter)