UCL Queen Square Institute of Neurology, UCL, London WC1N 3BG, United Kingdom.
UCL Institute of Cognitive Neuroscience, UCL, London, WC1N 3AZ, United Kingdom.
Cereb Cortex. 2023 Jun 20;33(13):8792-8802. doi: 10.1093/cercor/bhad162.
Hippocampal theta oscillations have been implicated in associative memory in humans. However, findings from electrophysiological studies using scalp electroencephalography or magnetoencephalography, and those using intracranial electroencephalography are mixed. Here we asked 10 pre-surgical epilepsy patients undergoing intracranial electroencephalography recording, along with 21 participants undergoing magnetoencephalography recordings, to perform an associative memory task, and examined whether hippocampal theta activity during encoding was predictive of subsequent associative memory performance. Across the intracranial electroencephalography and magnetoencephalography studies, we observed that theta power in the hippocampus increased during encoding, and that this increase differed as a function of subsequent memory, with greater theta activity for pairs that were successfully retrieved in their entirety compared with those that were not remembered. This helps to clarify the role of theta oscillations in associative memory formation in humans, and further, demonstrates that findings in epilepsy patients undergoing intracranial electroencephalography recordings can be extended to healthy participants undergoing magnetoencephalography recordings.
海马体θ 振荡被认为与人类的联想记忆有关。然而，头皮脑电图或脑磁图的电生理学研究以及颅内脑电图的研究结果却存在差异。在这里，我们要求 10 名接受颅内脑电图记录的术前癫痫患者和 21 名接受脑磁图记录的参与者执行联想记忆任务，并检查编码期间海马体θ 活动是否可预测随后的联想记忆表现。在颅内脑电图和脑磁图研究中，我们观察到在编码过程中海马体的θ 功率增加，并且这种增加是后续记忆的功能，与完全成功回忆的记忆对相比，未被记住的记忆对的θ 活动更大。这有助于阐明θ 振荡在人类联想记忆形成中的作用，并且进一步表明，在接受颅内脑电图记录的癫痫患者中发现的结果可以扩展到接受脑磁图记录的健康参与者。
