Lee Han, Simpson Gregory V, Logothetis Nikos K, Rainer Gregor
Max Planck Institute for Biological Cybernetics, Spemannstrasse 38, D-72076 Tübingen, Germany.
Neuron. 2005 Jan 6;45(1):147-56. doi: 10.1016/j.neuron.2004.12.025.
Working memory has been linked to elevated single neuron discharge in monkeys and to oscillatory changes in the human EEG, but the relation between these effects has remained largely unexplored. We addressed this question by measuring local field potentials and single unit activity simultaneously from multiple electrodes placed in extrastriate visual cortex while monkeys were performing a working memory task. We describe a significant enhancement in theta band energy during the delay period. Theta oscillations had a systematic effect on single neuron activity, with neurons emitting more action potentials near their preferred angle of each theta cycle. Sample-selective delay activity was enhanced if only action potentials emitted near the preferred theta angle were considered. Our results suggest that extrastriate visual cortex is involved in short-term maintenance of information and that theta oscillations provide a mechanism for structuring the recurrent interaction between neurons in different brain regions that underlie working memory.
工作记忆与猴子单个神经元放电增加以及人类脑电图的振荡变化有关，但这些效应之间的关系在很大程度上仍未得到探索。我们通过在猴子执行工作记忆任务时，从置于纹外视觉皮层的多个电极同时测量局部场电位和单个单元活动，来解决这个问题。我们描述了延迟期θ波段能量的显著增强。θ振荡对单个神经元活动有系统性影响，神经元在每个θ周期的偏好角度附近发放更多动作电位。如果仅考虑在偏好的θ角度附近发放的动作电位，样本选择性延迟活动会增强。我们的结果表明，纹外视觉皮层参与信息的短期维持，并且θ振荡为构成工作记忆基础的不同脑区神经元之间的循环相互作用提供了一种机制。
