Hanslmayr Simon, Spitzer Bernhard, Bäuml Karl-Heinz
Department of Experimental Psychology, Regensburg University, Universitätsstrase 31, Regensburg, Germany.
Cereb Cortex. 2009 Jul;19(7):1631-40. doi: 10.1093/cercor/bhn197. Epub 2008 Nov 11.
Prior studies, mostly using intentional learning, suggest that power increases in theta and gamma oscillations and power decreases in alpha and beta oscillations are positively related to later remembering. Using incidental learning, this study investigated whether these brain oscillatory subsequent memory effects can be differentiated by encoding task. One group of subjects studied material performing a semantic (deep) encoding task, whereas the other group studied the same material performing a nonsemantic (shallow) encoding task. Successful encoding in the semantic task was related to power decreases in the alpha (8-12 Hz) and beta (12-20 Hz) frequency band, and a power increase in the gamma band (55-70 Hz). In the shallow task, successful encoding was related to a power decrease in the alpha band and a power increase in the theta frequency band (4-7 Hz). A direct comparison of results between the 2 encoding tasks revealed that semantic subsequent memory effects were specifically reflected by power decreases in the beta (0.5-1.5 s) and the alpha frequency band (0.5-1.0 s), whereas nonsemantic subsequent memory effects were specifically reflected by a power increase in the theta frequency band (0.5-1.0 s).
先前的研究大多采用有意学习，结果表明，θ波和γ波振荡功率增加以及α波和β波振荡功率降低与后续记忆呈正相关。本研究采用附带学习，调查了这些脑振荡后续记忆效应是否可以通过编码任务来区分。一组受试者在执行语义（深度）编码任务时学习材料，而另一组受试者在执行非语义（浅层）编码任务时学习相同的材料。语义任务中的成功编码与α频段（8-12赫兹）和β频段（12-20赫兹）的功率降低以及γ频段（55-70赫兹）的功率增加有关。在浅层任务中，成功编码与α频段的功率降低以及θ频段（4-7赫兹）的功率增加有关。对这两种编码任务的结果进行直接比较发现，语义后续记忆效应具体表现为β频段（0.5-1.5秒）和α频段（0.5-1.0秒）的功率降低，而非语义后续记忆效应则具体表现为θ频段（0.5-1.0秒）的功率增加。
