To Tung V, Wang David X, Wolfe Cody B, Lega Bradley C
Department of Neurological Surgery, UT Southwestern Medical Center, Dallas, TX, USA.
O'Donnell Brain Institute, UT Southwestern Medical Center, Dallas, TX, USA.
Nat Commun. 2025 Jul 25;16(1):6845. doi: 10.1038/s41467-025-61464-z.
In humans, the hippocampus exhibits evident structural and connectivity differences along the longitudinal axis. Experiments in rodents and more recently in human subjects have stimulated several theories of functional longitudinal specialization. This question pertains directly to the management of neurosurgical patients, as nascent technologies permit more precise treatments that can selectively spare longitudinal regions. With this in mind, we investigated hippocampal longitudinal specialization in 32 human intracranial EEG subjects as they performed an associative recognition episodic memory task. Utilizing the behavioral contrasts available in this task, we characterize the neurophysiological features that distinguish the anterior versus posterior hippocampal activity during recollection and familiarity-based memory retrieval, as well as novelty processing. We use subspace representations to characterize longitudinal differences in the temporal dynamics of key computational processes ascribed to the hippocampus, namely pattern separation and pattern completion. We place our findings in the context of existing models, adding to sparse literature using direct brain recordings to explicate the functional differentiation along the hippocampal longitudinal axis in humans.
在人类中，海马体沿纵轴表现出明显的结构和连接差异。对啮齿动物以及最近对人类受试者进行的实验催生了几种关于功能纵向特化的理论。这个问题直接关系到神经外科患者的治疗，因为新兴技术允许进行更精确的治疗，能够选择性地保留纵向区域。考虑到这一点，我们对32名接受颅内脑电图监测的人类受试者进行了研究，观察他们在执行联想识别情景记忆任务时海马体的纵向特化情况。利用该任务中可用的行为对比，我们描述了在回忆、基于熟悉度的记忆检索以及新奇性处理过程中，区分海马体前部与后部活动的神经生理特征。我们使用子空间表示来描述归因于海马体的关键计算过程在时间动态上的纵向差异，即模式分离和模式完成。我们将我们的研究结果置于现有模型的背景下，为利用直接脑记录来阐明人类海马体纵轴上功能分化的稀疏文献增添了内容。
