Burkitt A N, Clark G M
Bionic Ear Institute, East Melbourne, Victoria 3002, Australia.
Neural Comput. 2001 Dec;13(12):2639-72. doi: 10.1162/089976601317098475.
The timing information contained in the response of a neuron to noisy periodic synaptic input is analyzed for the leaky integrate-and-fire neural model. We address the question of the relationship between the timing of the synaptic inputs and the output spikes. This requires an analysis of the interspike interval distribution of the output spikes, which is obtained in the gaussian approximation. The conditional output spike density in response to noisy periodic input is evaluated as a function of the initial phase of the inputs. This enables the phase transition matrix to be calculated, which relates the phase at which the output spike is generated to the initial phase of the inputs. The interspike interval histogram and the period histogram for the neural response to ongoing periodic input are then evaluated by using the leading eigenvector of this phase transition matrix. The synchronization index of the output spikes is found to increase sharply as the inputs become synchronized. This enhancement of synchronization is most pronounced for large numbers of inputs and lower frequencies of modulation and also for rates of input near the critical input rate. However, the mutual information between the input phase of the stimulus and the timing of output spikes is found to decrease at low input rates as the number of inputs increases. The results show close agreement with those obtained from numerical simulations for large numbers of inputs.
针对漏电积分发放神经模型，分析了神经元对有噪声的周期性突触输入响应中包含的时间信息。我们探讨了突触输入时间与输出尖峰之间的关系问题。这需要对输出尖峰的峰峰间隔分布进行分析，该分布是在高斯近似中获得的。根据输入的初始相位，评估对有噪声周期性输入的条件输出尖峰密度。这使得能够计算相位转移矩阵，该矩阵将输出尖峰产生时的相位与输入的初始相位联系起来。然后，通过使用该相位转移矩阵的主特征向量，评估神经元对持续周期性输入响应的峰峰间隔直方图和周期直方图。发现随着输入变得同步，输出尖峰的同步指数急剧增加。对于大量输入、较低调制频率以及接近临界输入速率的输入速率，这种同步增强最为明显。然而，发现随着输入数量增加，在低输入速率下，刺激的输入相位与输出尖峰时间之间的互信息会减少。结果表明，对于大量输入，与数值模拟结果非常吻合。
