Froemke Robert C, Dan Yang
Division of Neurobiology, Department of Molecular and Cell Biology, University of California, Berkeley 94720, USA.
Nature. 2002 Mar 28;416(6879):433-8. doi: 10.1038/416433a.
The strength of the connection between two neurons can be modified by activity, in a way that depends on the timing of neuronal firing on either side of the synapse. This spike-timing-dependent plasticity (STDP) has been studied by systematically varying the intervals between pre- and postsynaptic spikes. Here we studied how STDP operates in the context of more natural spike trains. We found that in visual cortical slices the contribution of each pre-/postsynaptic spike pair to synaptic modification depends not only on the interval between the pair, but also on the timing of preceding spikes. The efficacy of each spike in synaptic modification was suppressed by the preceding spike in the same neuron, occurring within several tens of milliseconds. The direction and magnitude of synaptic modifications induced by spike patterns recorded in vivo in response to natural visual stimuli were well predicted by incorporating the suppressive inter-spike interaction within each neuron. Thus, activity-induced synaptic modification depends not only on the relative spike timing between the neurons, but also on the spiking pattern within each neuron. For natural spike trains, the timing of the first spike in each burst is dominant in synaptic modification.
两个神经元之间连接的强度可通过活动进行调节，调节方式取决于突触两侧神经元放电的时间。这种尖峰时间依赖性可塑性（STDP）已通过系统地改变突触前和突触后尖峰之间的间隔进行了研究。在这里，我们研究了STDP在更自然的尖峰序列背景下是如何运作的。我们发现，在视觉皮层切片中，每个突触前/突触后尖峰对之间对突触修饰的贡献不仅取决于该对尖峰之间的间隔，还取决于先前尖峰的时间。同一神经元中先前的尖峰在几十毫秒内发生时，会抑制每个尖峰在突触修饰中的效力。通过纳入每个神经元内的抑制性尖峰间相互作用，可以很好地预测在体内记录的响应自然视觉刺激的尖峰模式所诱导的突触修饰的方向和幅度。因此，活动诱导的突触修饰不仅取决于神经元之间的相对尖峰时间，还取决于每个神经元内的尖峰模式。对于自然尖峰序列，每个爆发中第一个尖峰的时间在突触修饰中起主导作用。
