Orientation selectivity of synaptic input to neurons in mouse and cat primary visual cortex.
Orientation selectivity of synaptic input to neurons in mouse and cat primary visual cortex.
复制标题
DOI：
10.1523/jneurosci.2039-11.2011
复制
发表时间：
2011-08-24
期刊：
影响因子：
--
通讯作者：
Priebe NJ
中科院分区：
文献类型：
--
作者：
Tan AY;Brown BD;Scholl B;Mohanty D;Priebe NJ
初级视皮层（V1）是哺乳动物出现方向选择性的部位：V1的视丘脑传入对所有刺激方向的反应相同，而其靶V1神经元对刺激方向的反应有选择性。V1中的方向选择性的出现长期以来一直是研究皮层计算的模型。最近的证据表明，方向选择性在小鼠V1开放皮质计算解剖的遗传和成像工具，但也提出了两个基本问题：1）方向选择性在小鼠V1神经元与以前描述的物种相比？2)在小鼠V1中，方向选择性的突触基础是什么？方向选择性在小鼠和猫，在传统上已经取得了这样的措施，比较表明，方向选择性在小鼠V1是弱于猫V1，但尖峰阈值起着类似的作用，在缩小膜电位和尖峰率之间的选择性。为了揭示方向选择性的突触基础，我们从小鼠V1神经元进行了体内全细胞记录，比较神经元的输入选择性-基于膜电位，突触兴奋和突触抑制-基于尖峰的输出选择性。我们发现，神经元的兴奋性和抑制性的输入是选择性的相同的刺激方向是它的膜电位响应，抑制性的选择性是不是比兴奋性的选择性更广泛。抑制与兴奋有不同的动力，适应更快。在具有时间调制反应的神经元中，兴奋和抑制的时间在小鼠和猫中是不同的。
Primary visual cortex (V1) is the site at which orientation selectivity emerges in mammals: visual thalamus afferents to V1 respond equally to all stimulus orientations whereas their target V1 neurons respond selectively to stimulus orientation. The emergence of orientation selectivity in V1 has long served as a model for investigating cortical computation. Recent evidence for orientation selectivity in mouse V1 opens cortical computation to dissection by genetic and imaging tools, but also raises two essential questions: 1) how does orientation selectivity in mouse V1 neurons compare with that in previously described species? 2) what is the synaptic basis for orientation selectivity in mouse V1? A comparison of orientation selectivity in mouse and in cat, where such measures have traditionally been made, reveals that orientation selectivity in mouse V1 is weaker than in cat V1, but that spike threshold plays a similar role in narrowing selectivity between membrane potential and spike rate. To uncover the synaptic basis for orientation selectivity, we made whole-cell recordings in vivo from mouse V1 neurons, comparing neuronal input selectivity - based on membrane potential, synaptic excitation, and synaptic inhibition - to output selectivity based on spiking. We found that a neuron's excitatory and inhibitory inputs are selective for the same stimulus orientations as is its membrane potential response, and that inhibitory selectivity is not broader than excitatory selectivity. Inhibition has different dynamics than excitation, adapting more rapidly. In neurons with temporally modulated responses, the timing of excitation and inhibition was different in mice and cats.