Homeostatic role of heterosynaptic plasticity: models and experiments.
Homeostatic role of heterosynaptic plasticity: models and experiments.
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DOI：
10.3389/fncom.2015.00089
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发表时间：
2015
影响因子：
3.2
通讯作者：
Volgushev M
中科院分区：
文献类型：
--
作者：
Chistiakova M;Bannon NM;Chen JY;Bazhenov M;Volgushev M
同突触赫布型可塑性提供了一种在各种生物系统发育过程中学习和完善连接的细胞机制。在这篇综述中，我们认为，一个互补形式的可塑性异突触可塑性，代表了一个必要的细胞成分的突触重量和神经元活动的稳态调节。理论和建模研究已经很好地阐明了一个稳态机制，它强烈地约束了赫布联想可塑性所施加的失控动力学所需的属性。这种机制应该有力地支持神经元网络和突触竞争的操作的稳定性，包括非活动突触的变化，并且在与赫布型可塑性相似的时间尺度上操作。异突触可塑性的实验观察到的属性介绍了它作为一个强有力的候选人，以履行这一稳态的作用。随后的建模研究将异突触可塑性纳入具有Hebbian突触的模型神经元（利用STDP学习规则），证实了其稳健提供稳定性和竞争的能力。相比之下，稳态突触缩放的性质，这是由极端和长期（小时和天）的神经元活动的变化触发，不适合两个关键的要求，一个假设的稳态机制需要提供稳定的操作，在面对正在进行的突触变化驱动的赫布型学习规则。稳态突触标度的触发和时间尺度与赫布型可塑性的触发和时间尺度有着根本的不同。我们的结论是，heterosynaptic可塑性，这是由相同的情节触发的强烈的突触后活动，并在相同的时间尺度上运作的赫布型关联可塑性，是非常适合在持续的突触可塑性的稳态作用。
Homosynaptic Hebbian-type plasticity provides a cellular mechanism of learning and refinement of connectivity during development in a variety of biological systems. In this review we argue that a complimentary form of plasticity—heterosynaptic plasticity—represents a necessary cellular component for homeostatic regulation of synaptic weights and neuronal activity. The required properties of a homeostatic mechanism which acutely constrains the runaway dynamics imposed by Hebbian associative plasticity have been well-articulated by theoretical and modeling studies. Such mechanism(s) should robustly support the stability of operation of neuronal networks and synaptic competition, include changes at non-active synapses, and operate on a similar time scale to Hebbian-type plasticity. The experimentally observed properties of heterosynaptic plasticity have introduced it as a strong candidate to fulfill this homeostatic role. Subsequent modeling studies which incorporate heterosynaptic plasticity into model neurons with Hebbian synapses (utilizing an STDP learning rule) have confirmed its ability to robustly provide stability and competition. In contrast, properties of homeostatic synaptic scaling, which is triggered by extreme and long lasting (hours and days) changes of neuronal activity, do not fit two crucial requirements for a hypothetical homeostatic mechanism needed to provide stability of operation in the face of on-going synaptic changes driven by Hebbian-type learning rules. Both the trigger and the time scale of homeostatic synaptic scaling are fundamentally different from those of the Hebbian-type plasticity. We conclude that heterosynaptic plasticity, which is triggered by the same episodes of strong postsynaptic activity and operates on the same time scale as Hebbian-type associative plasticity, is ideally suited to serve a homeostatic role during on-going synaptic plasticity.