Decoding temporal information: A model based on short-term synaptic plasticity
Decoding temporal information: A model based on short-term synaptic plasticity
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DOI：
10.1523/jneurosci.20-03-01129.2000
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发表时间：
2000-02-01
影响因子：
5.3
通讯作者：
Buonomano, DV
中科院分区：
文献类型：
--
作者：
Buonomano, DV
本文提出，兴奋性-抑制性相互作用平衡的短期可塑性和动态变化可能是时间信息解码的基础，即时间选择性神经元的产生。我们最初的方法是模拟兴奋性-抑制性双突触回路。这种回路由单一的兴奋性和抑制性神经元组成，并结合了EPSP、IPSP和慢速IPSP的短期可塑性。我们首先证明了通过平行改变不同突触的突触权重，可以调整细胞对不同时间间隔的选择性反应。换句话说，时间调谐可以依赖于突触强度的长期变化，而不需要改变时间属性的时间常数。当在双突触回路中研究的单位被合并到一个更大的单层网络中时，这些单位表现出从无间隔调谐到间隔选择性调谐的广泛范围的时间选择性。时间调谐的可变性依赖于突触强度的可变性。该网络作为一个整体包含了广泛范围内的稳健的人口编码。重要的是，同样的网络能够区分简单的时间序列。这些结果认为，神经电路本质上能够在数十到数百毫秒的时间尺度上处理时间信息，可能不需要专门的机制，如延迟线或振荡器。
In the current paper it is proposed that short-term plasticity and dynamic changes in the balance of excitatory-inhibitory interactions may underlie the decoding of temporal information, that is, the generation of temporally selective neurons. Our initial approach was to simulate excitatory-inhibitory disynaptic circuits. Such circuits were composed of a single excitatory and inhibitory neuron and incorporated short-term plasticity of EPSPs and IPSPs and slow IPSPs. We first showed that it is possible to tune cells to respond selectively to different intervals by changing the synaptic weights of different synapses in parallel. In other words, temporal tuning can rely on long-term changes in synaptic strength and does not require changes in the time constants of the temporal properties. When the units studied in disynaptic circuits were incorporated into a larger single-layer network, the units exhibited a broad range of temporal selectivity ranging from no interval tuning to interval-selective tuning. The variability in temporal tuning relied on the variability of synaptic strengths. The network as a whole contained a robust population code for a wide range of intervals. Importantly, the same network was able to discriminate simple temporal sequences. These results argue that neural circuits are intrinsically able to process temporal information on the time scale of tens to hundreds of milliseconds and that specialized mechanisms, such as delay lines or oscillators, may not be necessary.