Prehension in the pigeon. I. Descriptive analysis.
Prehension in the pigeon. I. Descriptive analysis.
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鸽子的预感。
DOI：
10.1007/bf00249908
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发表时间：
1989
影响因子：
2
通讯作者：
Zeigler,HP
中科院分区：
文献类型：
--
作者：
Bermejo,R;Allan,RW;Houben,AD;Deich,JD;Zeigler,HP
鸽子吃东西需要一系列的颚部运动，其中一些运动具有抓握的功能；也就是说，它们被用于抓取和操纵物体。这些抓握行为非常短暂（30-80毫秒），会根据食物的大小调整下巴的张开幅度，由一个涉及相对较少肌肉的效应系统调节，并可受“反射性”和“自愿”控制。这种结构简单和功能复杂的结合表明，鸽子的下颌运动可能为研究目标运动中的运动控制机制提供一个有用的“模型系统”。本报告提供了进食过程中下颌张开运动的分类，并初步确定了每个运动类别与食物物体大小的比例。在对六种不同大小（直径3.2-11.1毫米）的球形食物颗粒的反应过程中，使用可产生间隙（即喙间距离）连续记录的传感系统监测下颌运动。然后使用计算机辅助评分程序对运动课程进行分配。确定了每个运动类别的颚开口幅度与目标大小的函数。确定了四种下颌运动类型：前啄（就在啄食之前），抓握（在啄食过程中但在接触目标之前做出的张开运动），下颌运动（用于在口腔内定位和运输物体的运动）和吞咽。对于这些运动类别中的两个（抓取，下颌骨），下颌张开幅度按比例缩放到颗粒大小，但缩放函数的方式不同，反映了两种行为的功能要求。然而，对于这两种运动，数据表明关于初始间隙的信息是用来控制打开幅度的。结果表明，在抓握过程中，打开幅度对刺激大小的调节涉及视觉输入和“开环”控制机制，而在下颌骨中，打开幅度的调节涉及触觉输入和“闭环”控制机制。
Eating in the pigeon involves a series of jaw movements some of which serve a prehensile function; i.e., they are utilized in the grasping and manipulation of objects. These prehensile behaviors are extremely brief (30–80 ms), produce an adjustment of jaw opening amplitude to the size of the food object, are mediated by an effector system involving a relatively small number of muscles and are amenable to both “reflexive” and “voluntary” control. This combination of structural simplicity and functional complexity suggests that the pigeon's jaw movements may provide a useful “model system” for the study of motor control mechanisms in targeted movements. The present report provides a classification of jaw opening movements occurring during eating and a preliminary determination of the extent to which each movement class is scaled to the size of the food object. Jaw movements were monitored during responses to spherical food pellets of six different sizes (3.2–11.1 mm in diameter) using a transducing system which produces a continuous record of gape (i.e., interbeak distance). Assignment to movement classes was then carried out using a computer-assisted scoring program. Functions relating jaw opening amplitude to target size were determined for each movement class. Four jaw movement classes were identified: Prepecks (just prior to pecking), Grasps (opening movements made during pecking but prior to contact with the target), Mandibulations (movements serving to position and transport the object within the buccal cavity) and Swallows. For two of these movement classes (Grasps, Mandibulations) jaw opening amplitude is scaled to pellet size but the scaling functions differ in ways that reflect the functional requirements of the two behaviors. However, for both movements, the data suggest that information about initial gape is used to control opening amplitude. It is concluded that during Grasping, the adjustment of opening amplitude to stimulus size involves visual inputs and “open-loop” control mechanisms, while for Mandibulation, that adjustment involves tactile input and “closed-loop” mechanisms.