学习时监测脑部活动能预测记忆情况

Research at Sandia National Laboratories has shown that it's possible to predict how well people will remember information by monitoring their brain activity while they study. A team under Laura Matzen of Sandia's cognitive systems group was the first to demonstrate predictions based on the results of monitoring test volunteers with electroencephalography (EEG) sensors.

For example, "if you had someone learning new material and you were recording the EEG, you might be able to tell them, 'You're going to forget this, you should study this again,' or tell them, 'OK, you got it and go on to the next thing,'" Matzen said.

The team monitored test subjects' brain activity while they studied word lists, then used the EEG to predict who would remember the most information. Because researchers knew the average percentage of correct answers under various conditions, they had a baseline of what brain activity looked like for good and poor memory performance. The computer model predicted five of 23 people tested would perform best. The model was correct: They remembered 72 percent of the words on average, compared to 45 percent for everyone else.

The study is part of Matzen's long-term goal to understand the Difference Related to Subsequent Memory, or Dm Effect, an index of brain activity encoding that distinguishes subsequently remembered from subsequently forgotten items. The measurable difference gives cognitive neuroscientists a way to test hypotheses about how information is encoded in memory.

She's interested in what causes the effect and what can change it, and hopes her research eventually leads to improvements in how students learn. She'd like to discover how training helps people performing at different levels and whether particular training works better for certain groups.

The study, funded under Sandia's Laboratory Directed Research and Development program (LDRD), had two parts: predicting how well someone will remember what's studied and predicting who will benefit most from memory training.

Matzen presented the results of the first part of the study in April at the Cognitive Neuroscience Society conference in Chicago. She presented preliminary findings on the second part this summer to the Cognitive Science and Technology External Advisory Board, made up of representatives of universities, industry and laboratories who advise the investment area team managing the LDRD portfolio.

The second part tested different types of memory training to see how they changed participants' memory performance and brain activity. One of Matzen's goals is to find out whether recording a person's brain activity while they use their natural approach to studying can predict what kind of training would work best for that person.