Whishaw I Q
Department of Psychology and NeuroDetective Inc., University of Lethbridge, Canada.
Behav Brain Res. 1996 Aug;78(2):101-11. doi: 10.1016/0166-4328(95)00236-7.
The forelimb and paw movements of mice were compared with those of rats in two skilled reaching for food tasks. Both species could use a single forelimb to reach for food, as measured in two different tasks, although performance was better and more consistent in rats than in mice. Both species located the food using olfaction, and moved from a diagonal supporting pattern in which support and postural adjustments came mainly from the contralateral to reaching forelimb and the ipsilateral to reaching hindlimb. Forelimb movements in both species could be divided into 3 components: (1) a transport component in which the limb is lifted, aimed, advanced, and pronated over the food using mainly movements of the upper limb; (2) a manipulatory component in which the digits are pronated over the food in an arpeggio movement and in which the digits grasp the food using grips that are scaled to the size of the food; and (3) a withdrawal component, in which the paw is supinated by adduction by the upper arm and by a movement about the wrist, as the food is withdrawn and presented to the mouth. Kinematic measures showed that the initial velocity of reaching in mice was slower than for rats, but otherwise the shape of the velocity curve and the trajectory of the limb movement, above and beyond the food pellet, were similar in both species. The results suggest that the motor control of reaching in the two rodent species is almost the same despite an evolutionary divergence that occurred about 20 million years ago. This profile of movement could be useful for investigating motor systems in normal mice and it could be applied to the analysis of motor systems in mutant and transgenic mice suspected of having motor abnormalities.
在两项熟练获取食物的任务中，对小鼠和大鼠的前肢及爪子运动进行了比较。在这两项不同任务中测量发现，两种动物都能用单个前肢获取食物，不过大鼠的表现比小鼠更好且更稳定。两种动物都利用嗅觉定位食物，并从一种对角支撑模式转变，在这种模式下，支撑和姿势调整主要来自对侧的前肢和同侧的后肢。两种动物的前肢运动都可分为三个部分：（1）运输部分，肢体抬起、瞄准、前进并旋前至食物上方，主要通过上肢运动完成；（2）操作部分，手指以琶音动作旋前至食物上方，手指使用根据食物大小调整的抓握方式抓取食物；（3）撤回部分，当食物被撤回并送到嘴边时，爪子通过上臂内收和手腕运动旋后。运动学测量表明，小鼠伸手的初始速度比大鼠慢，但除此之外，在超过食物颗粒的情况下，两种动物的速度曲线形状和肢体运动轨迹相似。结果表明，尽管这两种啮齿动物在大约2000万年前就发生了进化分歧，但它们伸手的运动控制几乎相同。这种运动模式可能有助于研究正常小鼠的运动系统，也可应用于分析怀疑有运动异常的突变和转基因小鼠的运动系统。
