摘要
用单位引导方法系统研究了鸽子、蛤蚧和石龙子的离顶盖通路单位反应特点 该通路视觉单位感受野较大 ;有照度和色觉两种光反应单位 ;在 3种动物的圆核和蛤蚧的前背侧室嵴总共找到 +B -Y ,+R -G ,+Y -B三种光谱拮抗单位 ;约半数视觉单位对运动物体反应良好 ,它们具有不同程度的方向选择性、朝向选择性以及运动物体大小选择性 ;2D运动单位中有一种覆盖缘反应单位 ,能区分在纹理背景上运动的纹理物体的前、后缘 ;3D单位只对在视轴方向运动的物体反应 ,其中一种对自远处飞近的物体产生强烈反应 ,此反应只发生在物体与眼即将‘碰撞’的瞬间 ,具有‘报警作用’ 在蛤蚧和鸟类的前背侧室嵴 (外纹体 )都发现既对运动物体反应 。
The visual response properties of the tectofugal pathway in pigeon, gecko, and Eumecus chinecsis were studied with standard extracellular records. The visual unit's receptive fields of lizard's and bird's Rt,ADVR or Ec usually are more than 40°.The order of their receptive field average size order is the optic tectum (includes nucleus isthmi)<Rt<ADVR or Ec. The light responsive units include luminance unit and color unit.Three opponent color units were found,they are+B-Y,+Y-B, and +R-G . The two dimensions units respond specifically to leading occlusion edge of kinematogram “object” that plays a covering role with either excitation or inhibition, but more interestingly, gives no response to the trailing disocclusion edge of the “object” or to a stationary or flashing spot. Three dimensions units is a motion in depth unit or a looming unit. The “toward” units responded to object moving on a collision cause toward the animal, and give their maximum response at a constant time before contact occurs even when the size of the stimulus or its velocity is varied over a large range of values. Therefore ,we propose that these units are signaling “time to collision”. Multimodal units were found in pigeon's and gecko's ADVR(Ec). they responded to moving object ,as well as to auditory or/ and tactile stimuli.
出处
《广西师范大学学报（自然科学版）》
CAS
2000年第2期67-72,共6页
Journal of Guangxi Normal University:Natural Science Edition
基金
国家自然科学基金!( 3 9760 0 1 6)
加拿大自然科学和技术委员会资助项目
关键词
鸽子
蜥蜴
离顶盖通路
电生理
鸟类
爬行类
pigeon
lizard
tectofugal pathway
electrophysiological study
siren of time to collision
