Princeton Neuroscience Institute, Princeton University, Princeton, New Jersey 08540, USA.
J Neurosci. 2010 Feb 17;30(7):2694-9. doi: 10.1523/JNEUROSCI.0567-09.2010.
Although the hippocampus plays a crucial role in encoding and retrieval of contextually mediated episodic memories, considerable controversy surrounds the role of the hippocampus in short-term or working memory. To examine both hippocampal and neocortical contributions to working memory function, we recorded electrocorticographic activity from widespread cortical and subcortical sites as 20 neurosurgical patients performed working memory tasks. These recordings revealed significant increases in 48-90 Hz gamma oscillatory power with memory load for two classes of stimuli: letters and faces. Sites exhibiting gamma increases with memory load appeared primarily in the hippocampus and medial temporal lobe. These findings implicate gamma oscillatory activity in the maintenance of both letters and faces in working memory and provide the first direct evidence for modulation of hippocampal gamma oscillations as humans perform a working memory task.
虽然海马体在编码和检索上下文介导的情景记忆方面起着至关重要的作用，但海马体在短期或工作记忆中的作用仍存在相当大的争议。为了研究海马体和新皮层对工作记忆功能的贡献，我们记录了 20 名神经外科患者在执行工作记忆任务时的广泛皮层和皮层下部位的脑电图活动。这些记录显示，对于两类刺激物：字母和面孔，随着记忆负荷的增加，48-90 Hz 的伽马振荡功率显著增加。随着记忆负荷增加而出现伽马增加的部位主要出现在海马体和内侧颞叶。这些发现表明，伽马振荡活动在工作记忆中对字母和面孔的维持都有影响，并为人类在执行工作记忆任务时海马体伽马振荡的调节提供了直接证据。
