According to the news report published by SciGuru.com Science News (http://www.sciguru.com), an important aspect of the study was the manipulation of the emotion of the words. Emotional memories are thought to be strong, reflecting their salience and future relevance. However, this study found that false memories (recall of never-presented critical words, i.e., the gist) was just as prominent when word lists were emotionally negative (slaughter, execute, shoot, etc) as when they were neutral. These results support the adaptive function of sleep in both remembering and in extracting memory details.
The research suggests an additional benefit of sleep in extracting the ‘gist’ of recent memories. In the study, Dr. Rebecca Spencer and colleagues at the University of Massachusetts, Amherst, had participants learn lists of related words (bowl, spoon, morning, breakfast, milk). Importantly, each list lacked a critical word which reflected the gist of the list (cereal). When recall of the lists was probed after sleep, participants were more likely to recall those critical words reflecting the gist of the list than they were if recall took place after wake.
The science news report appeared in SciGuru.com was based on a paper recently published in the journal PLOS one. Full news report is available at http://www.sciguru.com/