Softness discrimination with a tool
Softness discrimination with a tool
复制标题
DOI：
10.1152/jn.2000.83.4.1777
复制
发表时间：
2000-04-01
影响因子：
2.5
通讯作者：
LaMotte, RH
中科院分区：
文献类型：
--
作者：
LaMotte, RH
用工具来描述柔软度。J.神经生理素。83：1777-1786,2000。在不同的实验条件下，人们对手持工具(手写笔)不同顺应性的橡胶物体的柔软度进行了测量，这些条件与工具的使用方式和可用的感觉信息的种类不同。当受试者主动轻敲或按压符合要求的物体时，他们也会通过触控笔识别柔软度，就像他们通过指垫直接接触物体一样。对手写笔的辨别不受手写笔是由一根手指还是两根手指控制的影响。在敲击或按下精密握持的手写笔时，握力以前增加，与压缩力同时达到最大值，并与压缩力平行减小。这种关系暗示了基于运动系统的内部模型和物体的物理属性的预期运动控制。与用手写笔按压物体相比，敲击时的辨别力要好得多。这被认为是由于触控笔在敲击过程中敲击并缩进物体时，力量速度迅速增加而产生的触觉提示的存在。在敲击过程中，触针对物体产生的压缩力的大小和速度越大，物体就越硬。在穿戴和敲击过程中的另一个提示，可能是动觉，是针笔对样本的压痕大小，越大，物体越软。当实验者以大致相同的速度敲击与受试者被动指垫接触的触笔时，受试者在没有动觉的情况下，仅通过触觉提示就可以区分柔软度上的差异。如果一对中较软的试件以略高于较硬的试件的速度敲击，则识别能力会恶化；如果试件按在触针上，而不产生机械接触的触觉提示，则不可能。相反，在主动按压过程中可以辨别，并且在主动敲击过程中不受速度变化的影响。TI的结论是，在主动动作中，动觉信息和中枢传出指令的知识提供了被动触摸中不存在的有用线索。这些线索允许观察者区分物体顺应性的差异，而不是被应用速度的差异所混淆。
Softness discrirnination with a tool. J. Neurophysiol. 83: 1777-1786, 2000. The abilities of humans to discriminate the softness of rubber objects of differing compliance with a handheld tool (a stylus) was measured under experimental conditions that differed as to how the tool was used and the kind of sensory information available. When the subject actively tapped or pressed the compliant objects, they discriminated softness as well by means of a stylus as they did by contacting the objects directly with the fingerpad. Discrimination with the stylus was unaffected by whether the stylus was controlled by one or two fingers. While tapping or pressing a stylus held in a precision grip, the grip force increased before, reached a maximum at the same time as, and decreased in parallel with the compressional force. This relationship was suggestive of anticipatory motor control based on an internal model of the motor system and the physical properties of the object. Discrimination was significantly better when tapping as opposed to pressing the objects with the stylus. This was hypothesized as due to the presence of tactile cues generated by the rapid increase in force rate as the stylus struck and indented the object during tapping. During tapping, the magnitude and rate of compressional force produced by the stylus against the object were greater, the harder the object. An additional cue, possibly kinesthetic, during Dressing and tapping was the magnitude of indentation of the specimen by the stylus that was greater, the softer the object. Subjects could discriminate differences on softness by tactile cues alone in the absence of kinesthetic when compliant objects were tapped at approximately the same velocity by the experimenter against a stylus in contact with the subject's passive fingerpad. Discrimination deteriorated if the softer specimen of a pair was tapped with a slightly greater velocity than the harder and not possible if the specimens were pressed against the stylus without generating tactile cues of mechanical contact. In contrast, discrimination was possible during active pressing and unaffected by variations in velocity during active tapping. TI is concluded that during active movements, kinesthetic information and knowledge of central efferent commands provide useful cues that are not present during passive touch. These cues allow the observer to discriminate differences in object compliance not confounded by differences in applied velocity.