Shevelev I A, Lazareva N A, Sharaev G A, Novikova R V, Tikhomirov A S
Department of Sensory Physiology, Institute of Higher Nervous Activity and Neurophysiology, Russian Academy of Sciences, Moscow.
Neuroscience. 1999 Jan;88(1):17-25. doi: 10.1016/s0306-4522(98)00168-7.
Characteristics of responses and background activity, as well as of tuning to a single bar orientation and to cross or corner shape and orientation have been compared in one third (561174) of neurons in the cat striate cortex. Shortening of the response latency to cross vs bar, to corner vs bar and to corner vs cross was revealed in most of the units studied. Direct correlation between the response and tuning characteristics for bar, cross and corner was revealed: units with better tuning to one type of stimulus were typically better tuned to the other types of stimuli. At the middle cortical depth (700-1200 microm from the surface) we found a reliable improvement of response magnitude and latency, cross/bar response ratio and selectivity of tuning in comparison with more superficial and deeper layers. Although we could not find a direct correlation between characteristics of tuning to figures and the type of the receptive field (simple, complex or hypercomplex), our data pointed to a lower cross/bar ratio and selectivity of tuning in the units with small receptive fields. The functional implication of neuronal sensitivity to cross and corner and possible meaning of correlation between their functional characteristics are discussed.
我们比较了猫纹状皮层中三分之一（561174个）神经元的反应特性、背景活动，以及对单一条形方向、十字或角落形状和方向的调谐情况。在大多数被研究的神经元中，发现对十字与条形、角落与条形以及角落与十字的反应潜伏期缩短。揭示了对条形、十字和角落的反应与调谐特性之间的直接相关性：对一种刺激类型调谐更好的神经元通常对其他类型的刺激调谐也更好。在皮层中间深度（距表面700 - 1200微米），与更浅层和深层相比，我们发现反应幅度、潜伏期、十字/条形反应比率和调谐选择性有可靠的改善。虽然我们没有发现对图形的调谐特性与感受野类型（简单、复杂或超复杂）之间的直接相关性，但我们的数据表明，具有小感受野的神经元中，十字/条形比率和调谐选择性较低。讨论了神经元对十字和角落的敏感性的功能意义以及它们功能特性之间相关性的可能含义。
