Kilavik Bjørg Elisabeth, Silveira Luiz Carlos L, Kremers Jan
Department of Experimental Ophthalmology, University of Tübingen Eye Hospital, Röntgenweg 11, D-72076 Tübingen, Germany.
J Physiol. 2003 Feb 1;546(Pt 3):903-19. doi: 10.1113/jphysiol.2002.027748.
The responses of marmoset lateral geniculate neurones to stimuli that were composed of a sinusoidally modulating centre stimulus and a surround that was modulated in counterphase were measured. The size of the stimulus centre was varied. These measurements were repeated at different temporal frequencies between 1 and 30 Hz. The response amplitudes and phases depended in a characteristic manner on the stimulus centre size. The response behaviour could be modelled by assuming Gaussian responsivity profiles of the cells' receptive field (RF) centres and surrounds and a phase delay in the RF surround responses, relative to the centre, enabling the description of RF centre and surround response characteristics. We found that the RF centre-to-surround phase difference increased linearly with increasing temporal frequency, indicating a constant delay difference of about 4.5 to 6 ms. A linear model, including low-pass filters, a lead lag stage and a delay, was used to describe the mean RF centre and surround responses. The separate RF centre and surround responses were less band pass than the full receptive field responses of the cells. The linear model provided less satisfactory fits to M-cell responses than to those of P-cells, indicating additional nonlinearities.
测量了狨猴外侧膝状体神经元对由正弦调制的中心刺激和反相调制的周边组成的刺激的反应。刺激中心的大小是变化的。这些测量在1至30Hz的不同时间频率下重复进行。反应幅度和相位以一种特征性的方式取决于刺激中心的大小。通过假设细胞感受野（RF）中心和周边的高斯反应性轮廓以及RF周边反应相对于中心的相位延迟，可以对反应行为进行建模，从而能够描述RF中心和周边的反应特征。我们发现，RF中心到周边的相位差随着时间频率的增加而线性增加，表明恒定延迟差约为4.5至6毫秒。使用包括低通滤波器、超前滞后阶段和延迟的线性模型来描述平均RF中心和周边反应。与细胞的完整感受野反应相比，单独的RF中心和周边反应的带通特性较差。线性模型对M细胞反应的拟合不如对P细胞反应的拟合令人满意，表明存在额外的非线性。
