For any type of goal-directed hand and eye movement, it is important to determine the position of the target. Though many of these movements are directed toward visual targets, humans also perform movements to targets derived by somatosensory information only, such as proprioceptive (sensory signals about static limb position), kinaesthetic (sensory signals about limb movement), and tactile signals (sensory signals about touch on skin). In this study we investigated how each of these types of somatosensory information influences goal-directed hand and eye movements. Further, we examined whether somatosensory target information has a differential influence on isolated and combined eye-hand movements. Participants performed right-hand reaching, eye, or coordinated eye-hand movements to their left index or middle fingers in the absence of any visual information. We varied somatosensory target information by allowing proprioceptive, proprioceptive-kinaesthetic, proprioceptive-tactile, or proprioceptive-kinaesthetic-tactile information. Reach endpoint precision was poorest when the target was derived by proprioceptive information only, but improved when two different types of input were available. In addition, reach endpoints in conditions with kinaesthetic target information were systematically shifted toward the direction of movement, while static somatosensory information decayed over time and led to systematic undershoots of the reach target location. In contrast to the effect on reaches, somatosensory information did not influence gaze endpoint accuracy or precision. When performing coordinated eye-hand movements reach accuracy and gaze endpoint precision improved, suggesting a bidirectional use of efferent information. We conclude that somatosensory target information influence endpoint control differently for goal-directed hand and eye movements to unseen targets.

中文翻译：

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体感目标信息用于达到但不用于扫视眼球运动。

对于任何类型的以目标为导向的手部和眼球运动，确定目标的位置都很重要。虽然这些运动中有许多是针对视觉目标的，但人类也会对仅由体感信息得出的目标进行运动，例如本体感觉（关于静态肢体位置的感觉信号）、动觉（关于肢体运动的感觉信号）和触觉信号（关于肢体运动的感觉信号）关于接触皮肤）。在这项研究中，我们调查了这些类型的体感信息如何影响目标导向的手部和眼球运动。此外，我们检查了体感目标信息是否对孤立的和组合的眼手运动有不同的影响。参与者进行右手伸手，眼睛，或在没有任何视觉信息的情况下协调左手食指或中指的眼手运动。我们通过允许本体感觉、本体感觉-动觉、本体-触觉或本体-动觉-触觉信息来改变体感目标信息。当目标仅通过本体感受信息得出时，到达终点精度最差，但在两种不同类型的输入可用时有所提高。此外，在具有动觉目标信息的条件下，到达终点系统地向运动方向移动，而静态体感信息随时间衰减并导致到达目标位置的系统性下冲。与对范围的影响相反，体感信息不影响注视终点的准确度或精确度。当执行协调的眼手运动时，精度和注视端点精度得到提高，表明传出信息的双向使用。我们得出结论，体感目标信息对目标导向的手和眼运动对看不见的目标的影响不同。