Dragoi George, Buzsáki György
Center for Molecular and Behavioral Neuroscience, Rutgers, The State University of New Jersey, Newark, New Jersey 07102, USA.
Neuron. 2006 Apr 6;50(1):145-57. doi: 10.1016/j.neuron.2006.02.023.
Both episodic memory and spatial navigation require temporal encoding of the relationships between events or locations. In a linear maze, ordered spatial distances between sequential locations were represented by the temporal relations of hippocampal place cell pairs within cycles of theta oscillation in a compressed manner. Such correlations could arise due to spike "phase precession" of independent neurons driven by common theta pacemaker or as a result of temporal coordination among specific hippocampal cell assemblies. We found that temporal correlation between place cell pairs was stronger than predicted by a pacemaker drive of independent neurons, indicating a critical role for synaptic interactions and precise timing within and across cell assemblies in place sequence representation. CA1 and CA3 ensembles, identifying spatial locations, were active preferentially on opposite phases of theta cycles. These observations suggest that interleaving CA3 neuronal sequences bind CA1 assemblies representing overlapping past, present, and future locations into single episodes.
情景记忆和空间导航都需要对事件或位置之间的关系进行时间编码。在直线迷宫中，连续位置之间的有序空间距离以压缩的方式由海马体位置细胞对在θ振荡周期内的时间关系来表示。这种相关性可能是由于由共同的θ起搏器驱动的独立神经元的尖峰“相位进动”引起的，也可能是特定海马体细胞集合之间时间协调的结果。我们发现，位置细胞对之间的时间相关性比独立神经元的起搏器驱动所预测的更强，这表明突触相互作用以及细胞集合内部和之间的精确时间在位置序列表示中起着关键作用。识别空间位置的CA1和CA3神经元集群在θ周期的相反相位上优先活跃。这些观察结果表明，交错的CA3神经元序列将代表重叠的过去、现在和未来位置的CA1集合绑定到单个事件中。
