Movshon J A, Newsome W T
Center for Neural Science and Department of Psychology, New York University, New York, New York 10003, USA.
J Neurosci. 1996 Dec 1;16(23):7733-41. doi: 10.1523/JNEUROSCI.16-23-07733.1996.
We have previously shown that some neurons in extrastriate area MT are capable of signaling the global motion of complex patterns; neurons randomly sampled from V1, on the other hand, respond only to the motion of individual oriented components. Because only a small fraction of V1 neurons projects to MT, we wished to establish the processing hierarchy more precisely by studying the properties of those neurons projecting to MT, identified by antidromic responses to electrical stimulation of MT. The neurons that project from V1 to MT were directionally selective and, like other V1 neurons, responded only to the motion of the components of complex patterns. The projection neurons were predominantly "special complex," responsive to a broad range of spatial and temporal frequencies, and sensitive to very low stimulus contrasts. The projection neurons thus comprise a homogeneous and highly specialized subset of V1 neurons, consistent with the notion that V1 acts as clearing house of basic visual measurements, distributing information appropriately to higher cortical areas for specialized analysis.
我们之前已经表明，纹外区域MT中的一些神经元能够对复杂模式的整体运动进行信号传递；另一方面，从V1随机抽取的神经元仅对单个定向成分的运动做出反应。由于只有一小部分V1神经元投射到MT，我们希望通过研究那些投射到MT的神经元的特性来更精确地确定处理层次结构，这些神经元是通过对MT的电刺激进行逆向反应来识别的。从V1投射到MT的神经元具有方向选择性，并且与其他V1神经元一样，仅对复杂模式成分的运动做出反应。投射神经元主要是“特殊复杂型”，对广泛的空间和时间频率有反应，并且对非常低的刺激对比度敏感。因此，投射神经元构成了V1神经元的一个同质且高度专业化的子集，这与V1作为基本视觉测量的信息交换中心，将信息适当地分配到更高皮层区域进行专门分析的观点一致。
