Buzsáki G
Center for Molecular and Behavioral Neuroscience, Rutgers University, Newark, NJ 07102, USA.
J Sleep Res. 1998;7 Suppl 1:17-23. doi: 10.1046/j.1365-2869.7.s1.3.x.
In the awake brain, information about the external world reaches the hippocampus via the entorhinal cortex, whereas during sleep the direction of information flow is reversed: population bursts initiated in the hippocampus invade the neocortex. We suggest that neocortico-hippocampal transfer of information and the modification process in neocortical circuitries by the hippocampal output take place in a temporally discontinuous manner associated with theta/gamma oscillations. On the other hand, transfer of the stored representations to neocortical areas is carried by discrete quanta of cooperative neuronal bursts (called sharp wave bursts) initiated in the hippocampus during slow wave sleep. The spatio-temporal participation of principal cells in sharp waves is determined by experience-induced changes in the CA3 recurrent collateral matrix. The co-operative, converging pre-synaptic activity can induce localized fast spikes and associated calcium influx in the apical dendrites of CA1 pyramidal cells, a necessary condition for the induction of synaptic plasticity. In addition, the subcortical effects of hippocampal sharp wave bursts may be critical in the release of various hormones which, in turn, may affect synaptic plasticity. These observations suggest that sleep patterns in the limbic system are essential for the preservation of experience-induced synaptic modifications.
在清醒的大脑中，有关外部世界的信息通过内嗅皮质到达海马体，而在睡眠期间，信息流的方向则相反：海马体中引发的群体爆发侵入新皮质。我们认为，新皮质-海马体的信息传递以及海马体输出对新皮质回路的修饰过程是以与θ/γ振荡相关的时间上不连续的方式发生的。另一方面，存储表征向新皮质区域的传递是由慢波睡眠期间海马体中引发的离散的协同神经元爆发量子（称为尖波爆发）进行的。主细胞在尖波中的时空参与是由CA3递归侧支矩阵中经验诱导的变化决定的。协同的、汇聚的突触前活动可以在CA1锥体细胞的顶端树突中诱导局部快速尖峰和相关的钙内流，这是诱导突触可塑性的必要条件。此外，海马体尖波爆发的皮质下效应可能对各种激素的释放至关重要，而这些激素反过来可能影响突触可塑性。这些观察结果表明，边缘系统中的睡眠模式对于保存经验诱导的突触修饰至关重要。
