Department of Clinical and Experimental Epilepsy, UCL Queen Square Institute of Neurology, London, UK.
UCL Institute of Cognitive Neuroscience, London, UK.
Hippocampus. 2021 Feb;31(2):213-220. doi: 10.1002/hipo.23284. Epub 2020 Dec 2.
Hippocampal theta oscillations have been implicated in spatial memory function in both rodents and humans. What is less clear is how hippocampal theta interacts with higher frequency oscillations to support long-term memory. Here we asked 10 presurgical epilepsy patients undergoing intracranial EEG recording to perform a long-term spatial memory task in desktop virtual reality and found that increased theta power in two discrete bands ("low" 2-5 Hz and "high" 6-11 Hz) during cued retrieval was associated with improved task performance. Similarly, increased coupling between "low" theta phase and gamma amplitude during the same period was associated with improved task performance. Finally, low and high gamma amplitude appeared to peak at different phases of the theta cycle; providing a novel connection between human hippocampal function and rodent data. These results help to elucidate the role of theta oscillations and theta-gamma phase-amplitude coupling in human long-term memory.
海马体θ振荡被认为与啮齿类动物和人类的空间记忆功能有关。但目前尚不清楚海马体θ振荡如何与更高频率的振荡相互作用以支持长期记忆。在这里，我们要求 10 名接受颅内 EEG 记录的术前癫痫患者在桌面虚拟现实中执行长期空间记忆任务，发现提示检索期间两个离散频带（“低”2-5 Hz 和“高”6-11 Hz）中θ功率增加与任务表现的改善有关。同样，在此期间“低”θ相位和γ幅度之间的耦合增加与任务表现的改善有关。最后，低γ和高γ幅度似乎出现在θ周期的不同相位；为人类海马体功能和啮齿动物数据之间提供了新的联系。这些结果有助于阐明θ振荡和θ-γ 相位-幅度耦合在人类长期记忆中的作用。
