Zosimovskiĭ V A, Korshunov V A
Zh Vyssh Nerv Deiat Im I P Pavlova. 2010 Sep-Oct;60(5):568-81.
It is suggested that the information about a new stimulus from the neocortex is transferred to the hippocampus and forms there a transient trace in the form of a distributed pattern of modified synapses. During sleep, the neuronal populations which store this trace are reactivated and return to the neocortex the information necessary for consolidation of the permanent memory trace. A possible mechanism of the reactivation of the "learned" hippocampal neurons during memory consolidation is the reverberation of excitation in the neuronal circuits connecting the hippocampus and the entorhinal cortex. In rats, we recorded responses in hippocampal field CA1 to stimulation of the Schaffer collaterals with potentiated synapses during wakefulness and sleep. We showed that in the periods of deep sleep, after the discharge of CA1 neurons, the wave of excitation passes through the entorhinal cortex and via the perforant path fibers enters the hippocampus and the dentate gyrus, causing in the latter the discharge of neurons. The repeated discharge of the CA1 neurons develops as the result of interaction of the early wave which is returned directly via the perforant path fibers and the late wave which is returned via the Schaffer collaterals, but not through the dentate gyrus and hippocampal field CA3 (trisynaptic pathway), but, probably, through the field CA2.
有观点认为，来自新皮层的关于新刺激的信息会传递至海马体，并在那里以修饰突触的分布式模式形成一个短暂痕迹。在睡眠期间，存储该痕迹的神经元群体被重新激活，并将巩固永久记忆痕迹所需的信息返回至新皮层。在记忆巩固过程中，“学习过的”海马体神经元重新激活的一种可能机制是连接海马体和内嗅皮层的神经回路中的兴奋回响。在大鼠中，我们记录了清醒和睡眠期间海马体CA1区对具有增强突触的施affer侧支刺激的反应。我们发现，在深度睡眠期间，CA1神经元放电后，兴奋波穿过内嗅皮层，并通过穿通路径纤维进入海马体和齿状回，导致后者的神经元放电。CA1神经元的重复放电是由直接通过穿通路径纤维返回的早期波与通过施affer侧支返回的晚期波相互作用产生的，但不是通过齿状回和海马体CA3区（三突触通路），而是可能通过CA2区。
