论文标题
各种时间重新编码对小脑中帕夫洛维亚透明条件调节的影响
Influence of Various Temporal Recoding on Pavlovian Eyeblink Conditioning in The Cerebellum
论文作者
论文摘要
我们通过重复出现配对条件刺激（音调）和无条件的刺激（Airpuff）来考虑Pavlovian扬声器调节（EBC）。在小脑网络中研究了颗粒细胞对EBC的各种时间重现对EBC的影响，在该网络中，连接概率$ p_c $从Golgi到颗粒细胞的影响发生了变化。在$ P_C^*〜（= 0.029）$的最佳情况下，单个颗粒细胞相对于无条件的刺激显示出各种良好和不匹配的射击模式。然后，通过平行纤维（PFS）将这些固定的信号送入Purkinje细胞（PC）。在匹配良好的PF-PC突触的情况下，它们的突触权重通过强大的长期抑郁（LTD）强烈降低。另一方面，与不匹配的PF-PC突触几乎没有Ltd发生。 PF-PC的这种“有效”抑郁症可以有效地协调PC的发射，然后对小脑核神经元[引起条件反应（CR; EykeBlink）]有效抑制性协调。当学习试验通过一个阈值时，对CR的获取开始。在这种情况下，由于存在不匹配的射击组，CR的定时程度$ {\ cal t} _d $变得不错，该组在时间上扮演了保护障碍的角色。随着试验的进一步增加，由于匹配良好的射击组中强的LTD，CR的强度$ \ cal s $（对应于眼睑闭合的幅度）增加。因此，随着学习试验的增加，（总体）学习效率程度$ {\ cal l} _e $（考虑到CR的时机和强度）的CR会增加，最终变得饱和。通过从$ P_C^*$更改$ P_C $，我们还研究了EBC上各种时间重新编码的影响。因此发现，时间重新编码的各种越多，对Pavlovian EBC学习的有效性就越有效。
We consider the Pavlovian eyeblink conditioning (EBC) via repeated presentation of paired conditioned stimulus (tone) and unconditioned stimulus (airpuff). The influence of various temporal recoding of granule cells on the EBC is investigated in a cerebellar network where the connection probability $p_c$ from Golgi to granule cells is changed. In an optimal case of $p_c^*~(=0.029)$, individual granule cells show various well- and ill-matched firing patterns relative to the unconditioned stimulus. Then, these variously-recoded signals are fed into the Purkinje cells (PCs) through parallel-fibers (PFs). In the case of well-matched PF-PC synapses, their synaptic weights are strongly depressed through strong long-term depression (LTD). On the other hand, practically no LTD occurs for the ill-matched PF-PC synapses. This type of "effective" depression at the PF-PC synapses coordinates firings of PCs effectively, which then make effective inhibitory coordination on cerebellar nucleus neuron [which elicits conditioned response (CR; eyeblink)]. When the learning trial passes a threshold, acquisition of CR begins. In this case, the timing degree ${\cal T}_d$ of CR becomes good due to presence of the ill-matched firing group which plays a role of protection barrier for the timing. With further increase in the trial, strength $\cal S$ of CR (corresponding to the amplitude of eyelid closure) increases due to strong LTD in the well-matched firing group. Thus, with increasing the learning trial, the (overall) learning efficiency degree ${\cal L}_e$ (taking into consideration both timing and strength of CR) for the CR is increased, and eventually it becomes saturated. By changing $p_c$ from $p_c^*$, we also investigate the influence of various temporal recoding on the EBC. It is thus found that, the more various in temporal recoding, the more effective in learning for the Pavlovian EBC.
