A high frequency resonance in the responses of retinal ganglion cells to rapidly modulated stimuli: a computer model.
A high frequency resonance in the responses of retinal ganglion cells to rapidly modulated stimuli: a computer model.
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视网膜神经节细胞对快速调节刺激的反应中的高频共振：计算机模型。
DOI：
10.1017/s0952523806230104
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发表时间：
2006
影响因子：
1.9
通讯作者：
Kenyon,GT
中科院分区：
文献类型：
--
作者：
Miller,JA;Denning,KS;George,JS;Marshak,DW;Kenyon,GT
猫视网膜中活跃的Y型神经节细胞在对大的、快速调制的刺激的反应中表现出高频共振（HFR）。我们使用计算机模型来测试是否负反馈介导的轴突轴承无长突细胞对神经节细胞可以解释实验观察到的特性的HFRs。从模型神经节细胞记录的时间调制传递函数（tMTF）表现出HFR峰，其幅度，宽度和位置与实验数据定性一致。此外，轴突介导的反馈的宽空间分布占所观察到的HFR振幅随刺激大小的增加。模型相位图定性类似于从Y神经节细胞记录的那些，包括在我们的模型中与重叠HFR峰的低阶谐波的放大相一致的异常相位提前。当模型中轴突介导的反馈主要针对双极细胞时，其突触输出是分级的，或者当模型被线性滤波器的简单级联取代时，可以产生大的HFR峰，但异常相位提前的区域总是被消除，这表明强烈的非线性反馈回路的关键参与。为了研究高频震颤是否有助于视觉处理，我们通过快速调制自然图像来模拟高频眼震颤。在施加的抖动之上的视觉信号传达了对大型物体的增强表示。我们的结论是，通过放大眼震颤的反应，高频反应可能会选择性地增强处理大的图像功能。
Brisk Y-type ganglion cells in the cat retina exhibit a high frequency resonance (HFR) in their responses to large, rapidly modulated stimuli. We used a computer model to test whether negative feedback mediated by axon-bearing amacrine cells onto ganglion cells could account for the experimentally observed properties of HFRs. Temporal modulation transfer functions (tMTFs) recorded from model ganglion cells exhibited HFR peaks whose amplitude, width, and locations were qualitatively consistent with experimental data. Moreover, the wide spatial distribution of axon-mediated feedback accounted for the observed increase in HFR amplitude with stimulus size. Model phase plots were qualitatively similar to those recorded from Y ganglion cells, including an anomalous phase advance that in our model coincided with the amplification of low-order harmonics that overlapped the HFR peak. When axon-mediated feedback in the model was directed primarily to bipolar cells, whose synaptic output was graded, or else when the model was replaced with a simple cascade of linear filters, it was possible to produce large HFR peaks but the region of anomalous phase advance was always eliminated, suggesting the critical involvement of strongly non-linear feedback loops. To investigate whether HFRs might contribute to visual processing, we simulated high frequency ocular tremor by rapidly modulating a naturalistic image. Visual signals riding on top of the imposed jitter conveyed an enhanced representation of large objects. We conclude that by amplifying responses to ocular tremor, HFRs may selectively enhance the processing of large image features.