Center For Neuroscience, University of California, Davis, 1544 Newton Court, Davis, CA 95618, USA.
J Neurophysiol. 2011 Apr;105(4):1747-55. doi: 10.1152/jn.00921.2010. Epub 2011 Feb 2.
Previous rodent studies demonstrate movement-related increases in theta oscillations, and recent evidence suggests that multiple navigationally relevant variables are reflected in this activity. Human invasive recordings have revealed movement-related modulations in delta and theta activity, although it is unclear whether additional behavioral variables are responsible for modulating this neural activity during navigation. We tested the role of delta and theta oscillations during navigation by addressing whether spatial-related processing, in addition to speed and task variables, modulates delta and theta activity. Recording from 317 hippocampal intracranial electrodes in 10 patients undergoing seizure monitoring, we observed increasing delta and theta power with increasing virtual speed at significantly more electrodes than would be expected by chance, replicating previous findings in nonhuman mammals. Delta and theta power were more consistently modulated, however, as a function of spatial view, including when subjects looked at stores in the virtual environment both to find a relevant goal or for spatial updating. A significantly larger proportion of electrodes showed view-related effects than speed-related modulations. Although speed, task, and spatial view affected delta and theta activity, individual electrodes were most frequently modulated by only one variable, rather than a combination of variables. These electrodes likely sampled independent delta and theta generators, which reflected movement-related and allocentric processing, respectively. These results extend previous findings in nonhuman mammals and humans, expanding our knowledge of the role of human hippocampal low-frequency oscillations in navigation.
先前的啮齿动物研究表明，与运动相关的θ振荡增加，最近的证据表明，多个与导航相关的变量反映在这种活动中。人类侵入性记录显示，在活动期间，与运动相关的 δ 和 θ 活动有调节作用，尽管尚不清楚是否有其他行为变量负责调节这种神经活动。我们通过研究空间相关处理在导航中的作用，以及速度和任务变量，测试了 δ 和 θ 振荡在导航中的作用。在 10 名接受癫痫监测的患者中，我们从 317 个海马颅内电极中进行记录，观察到在明显更多的电极上，与虚拟速度增加相关的 δ 和 θ 功率增加，这与非人类哺乳动物的先前发现相吻合。然而，随着空间视图的增加，δ 和 θ 功率的调制更为一致，包括当受试者在虚拟环境中查看商店以寻找相关目标或进行空间更新时。与速度相关的调制相比，显示视图相关效果的电极比例明显更大。尽管速度、任务和空间视图影响 δ 和 θ 活动，但个体电极最常仅受一个变量而不是多个变量的调制。这些电极可能采样了独立的 δ 和 θ 发生器，分别反映了与运动相关和与环境中心相关的处理。这些结果扩展了非人类哺乳动物和人类的先前发现，扩展了我们对人类海马体低频振荡在导航中的作用的认识。
