据每日科学网近日报道，加州大学戴维斯分校的最新研究表明，大脑能否记忆并回想起某些事情，与大脑的状态密切相关。该研究发表在美国《国家科学院院刊》（PNAS）上。

加州大学戴维斯分校的研究人员测量了志愿者的一种特定频率的脑电波（西塔波），志愿者在测试中根据特定的上下文的背景，记忆一系列单词。随后志愿者要回忆是否见过某个单词，并回忆看到这个单词的上下文。结果表明，西塔波的高低与记忆的好坏相关，西塔波高则记忆表现良好。研究人员认为，在大多数情况下，大脑忙于处理大量与外界无关的大脑内部活动。当外部刺激出现后，大脑的内部模式立即与外部刺激发生互动。

研究人员表示，他们正在研究能否人为地将大脑调整到高西塔波的最佳记忆状态，并希望通过这一研究开发出针对失忆症的新疗法。（生物谷Bioon.com）

生物谷推荐原文出处：

Proceedings of the National Academy of Sciences    DOI： 10.1073/pnas.1014528108

Prestimulus theta activity predicts correct source memory retrieval

Addante, Richard J.; Watrous, Andrew J.; Yonelinas, Andrew P.; Ekstrom, Arne D.; Ranganath, Charan

Recent evidence indicates that the processing of a stimulus can be influenced by preceding patterns of brain activity. Herewe examine whether prestimulus oscillatory brain activity can influence the ability to retrieve episodic memories. Neuralactivity in the theta-frequency band (4–8 Hz) was enhanced before presentation of test items which elicited accurate recollectionof contextual details of the prior study episode (“source retrieval”), relative to trials for which item recognition was successfulbut source retrieval failed. Poststimulus theta activity was also related to source retrieval, and the magnitude of poststimulustheta was predicted by the magnitude of the prestimulus theta effects. The results suggest that ongoing neural processes occurringbefore stimulus onset might play a critical role in readying the brain for successful memory retrieval.