A neural network approach to the acoustic startle reflex and prepulse inhibition
A neural network approach to the acoustic startle reflex and prepulse inhibition
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DOI：
10.1016/s0361-9230(01)00607-4
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发表时间：
2001-09-15
影响因子：
3.8
通讯作者：
Früh, H
中科院分区：
文献类型：
--
作者：
Leumann, L;Sterchi, D;Früh, H
前脉冲抑制（PPI）是当强烈刺激之前有一个弱的非惊吓前刺激时惊吓反射的正常抑制。PPI被广泛用作感觉运动门控过程的模型，并已被证明在各种神经精神疾病（包括精神分裂症）中受损。我们已经用神经网络再现了类似惊吓的行为和基本的PPI修改。网络设计受到以下尝试的限制：（1）使用尽可能少的连接;（2）将神经解剖结构与模拟网络相关联。网络的性能进行了评估的行为的模拟运动神经元在响应于前脉冲和脉冲刺激提出了不同的铅间隔和前脉冲强度。延迟抑制途径通过脚桥核（PPTg）的脑桥尾侧网状核被认为是一个必要的，但不足以要求重现基本的PPI输出模式。其他要求包括（a）在或低于脑桥尾侧网状结构的低阈值，（B）抑制途径中的信号放大和（c）抑制途径中活性的延长。最合适的输出模式的模拟的理由，我们提出了一种机制，持续激活的PPTg由于递归连接。刺激，行为（电机输出）和底层架构之间的关系进行了讨论。潜在地，这种建模技术可以扩展到研究药物和更高的大脑区域对PPI的影响。(C)2001 Elsevier Science Inc.
Prepulse inhibition (PPI) is the normal suppression of the startle reflex when an intense stimulus is preceded by a weak non-startling prestimulus. PPI is widely used as a model for sensorimotor gating processes and has been shown to be impaired in various neuro psychiatric disorders, including schizophrenia. We have reproduced startle-like behavior and basic PPI modifications with a neural network. The network design was constrained by the attempt (1) to use as few connections as possible and (2) to relate neuroanatomical structures to the simulated network. Performance of the network was evaluated by the behavior of the simulated motor neurons in response to prepulse and pulse stimuli presented with various lead intervals and prepulse intensities. A delayed inhibitory pathway via the pedunculopontine nucleus (PPTg) to the caudal pontine reticular nucleus was found to be a necessary but insufficient requirement to reproduce basic PPI output patterns. Additional requirements included (a) a low threshold at or below the caudal pontine reticular formation, (b) signal amplification in the inhibitory pathway and (c) prolongation of activity in the inhibitory pathway. On the grounds of the most appropriate output patterns of the simulations, we propose a mechanism of sustained activation in the PPTg due to recursive connections. Relations between stimuli, behavior (motor output) and the underlying architecture are discussed. Potentially, this modeling technique can be extended to investigate the impact of drugs and higher brain regions on PPI. (C) 2001 Elsevier Science Inc.