Tag-trigger-consolidation: a model of early and late long-term-potentiation and depression.
Tag-trigger-consolidation: a model of early and late long-term-potentiation and depression.
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DOI：
10.1371/journal.pcbi.1000248
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发表时间：
2008-12
影响因子：
4.3
通讯作者：
Gerstner, Wulfram
中科院分区：
文献类型：
--
作者：
Clopath, Claudia;Ziegler, Lorric;Vasilaki, Eleni;Buesing, Lars;Gerstner, Wulfram
突触效能的改变需要是持久的，才能作为记忆的基础。在实验中，突触可塑性呈现出不同阶段，包括在突触可塑性早期阶段的长时程增强和长时程抑制（LTP/LTD）的诱导、突触标记的设定、蛋白质合成的触发过程，以及在突触可塑性晚期阶段导致突触巩固的缓慢转变。我们提出了一个数学模型来描述突触可塑性的这些不同阶段。该模型解释了大量关于突触标记和捕获、交叉标记以及LTP和LTD晚期阶段的实验数据。此外，该模型说明了LTP和LTD的诱导对电压和突触前刺激频率的依赖性。在从早期LTP到晚期LTP的转变过程中，增强突触的稳定是通过由突触群共享的蛋白质合成动力学实现的。这种共享过程的功能结果是，先前在同一突触后神经元上稳定的强突触或弱突触模式能很好地防止后来由单个突触上的LTP/LTD方案所诱导的改变。
人类和动物通过改变神经元之间连接的强度来学习，这种现象被称为突触可塑性。这些改变可以由相当短暂的刺激（有时仅持续几秒）诱导，但随后应该稳定数月或数年，以便对长期记忆有用。实验人员已经表明，突触会经历一系列步骤，将突触可塑性早期阶段的快速变化转变为晚期阶段的稳定记忆痕迹。在本文中，我们引入了一个由少量方程组成的模型，它能够描述突触可塑性早期阶段突触变化的诱导现象、蛋白质合成的触发过程以及最终的稳定。该模型涵盖了广泛的被称为标记实验的实验现象，并做出了可检验的预测。对突触稳定进行建模的能力对于理解动物和人类的学习与记忆过程至关重要，也是任何大规模大脑模型的必要组成部分。
Changes in synaptic efficacies need to be long-lasting in order to serve as a substrate for memory. Experimentally, synaptic plasticity exhibits phases covering the induction of long-term potentiation and depression (LTP/LTD) during the early phase of synaptic plasticity, the setting of synaptic tags, a trigger process for protein synthesis, and a slow transition leading to synaptic consolidation during the late phase of synaptic plasticity. We present a mathematical model that describes these different phases of synaptic plasticity. The model explains a large body of experimental data on synaptic tagging and capture, cross-tagging, and the late phases of LTP and LTD. Moreover, the model accounts for the dependence of LTP and LTD induction on voltage and presynaptic stimulation frequency. The stabilization of potentiated synapses during the transition from early to late LTP occurs by protein synthesis dynamics that are shared by groups of synapses. The functional consequence of this shared process is that previously stabilized patterns of strong or weak synapses onto the same postsynaptic neuron are well protected against later changes induced by LTP/LTD protocols at individual synapses. Humans and animals learn by changing the strength of connections between neurons, a phenomenon called synaptic plasticity. These changes can be induced by rather short stimuli (lasting sometimes only a few seconds) but should then be stable for months or years in order to be useful for long-term memory. Experimentalists have shown that synapses undergo a sequence of steps that transforms the rapid change during the early phase of synaptic plasticity into a stable memory trace in the late phase. In this paper we introduce a model with a small number of equations that can describe the phenomena of induction of synaptic changes during the early phase of synaptic plasticity, the trigger process for protein synthesis, and the final stabilization. The model covers a broad range of experimental phenomena known as tagging experiments and makes testable predictions. The ability to model the stabilization of synapses is crucial to understand learning and memory processes in animals and humans and a necessary ingredient for any large-scale model of the brain.
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DOI：
10.1073/pnas.89.10.4363
发表时间：
1992-05-15
影响因子：
11.1
作者：
DUDEK, SM;BEAR, MF
通讯作者：
BEAR, MF
影响因子：
3.8
作者：
KRUG, M;LOSSNER, B;OTT, T
通讯作者：
OTT, T
影响因子：
5.5
作者：
BLISS, TVP;GARDNERM.AR
通讯作者：
GARDNERM.AR
影响因子：
2.9
作者：
FREY, U;SCHROEDER, H;MATTHIES, H
通讯作者：
MATTHIES, H
影响因子：
4.3
作者：
Graupner M;Brunel N
通讯作者：
Brunel N