Avraham Guy, Sulimani Erez, Mussa-Ivaldi Ferdinando A, Nisky Ilana
Department of Biomedical Engineering, Ben-Gurion University of the Negev, Be'er-Sheva, Israel.
Zlotowski Center for Neuroscience, Ben-Gurion University of the Negev, Be'er-Sheva, Israel.
J Neurophysiol. 2019 Dec 1;122(6):2259-2271. doi: 10.1152/jn.00017.2019. Epub 2019 Oct 2.
The sensory system constantly deals with delayed feedback. Recent studies showed that playing a virtual game of pong with delayed feedback caused hypermetric reaching movements. We investigated whether this effect is associated with a perceptual bias. In addition, we examined the importance of the target in causing hypermetric movements. In a first experiment, participants played a delayed pong game and blindly reached to presented targets. Following each reaching movement, they assessed the position of the invisible cursor. We found that participants performed hypermetric movements but reported that the invisible cursor reached the target, suggesting that they were unaware of the hypermetria and that their perception was biased toward the target rather than toward their hand position. In a second experiment, we removed the visual target, and strikingly, the hypermetria vanished. Moreover, participants reported that the invisible cursor was located with their hand. Taking these results together, we conclude that the adaptation to the visuomotor delay during the pong game selectively affected the execution of goal directed movements, resulting in hypermetria and perceptual bias when movements are directed toward visual targets but not when such targets are absent. Recent studies showed that adaptation to visuomotor delays causes hypermetric movements in the absence of visual feedback, suggesting that visuomotor delay is represented using current state information. We report that this adaptation also affects perception. Importantly, both the motor and perceptual effects are selective to the representations that are used in the execution of goal-directed movements toward visual targets.
感觉系统不断应对延迟反馈。最近的研究表明，玩带有延迟反馈的虚拟乒乓球游戏会导致动作过度伸展。我们研究了这种效应是否与感知偏差有关。此外，我们还研究了目标在导致动作过度方面的重要性。在第一个实验中，参与者玩了一个延迟乒乓球游戏，并盲目地伸手去够呈现的目标。在每次伸手动作之后，他们评估不可见光标的位置。我们发现参与者表现出动作过度伸展，但报告说不可见光标到达了目标，这表明他们没有意识到动作过度，并且他们的感知偏向于目标而非自己手部的位置。在第二个实验中，我们移除了视觉目标，令人惊讶的是，动作过度消失了。此外，参与者报告说不可见光标与他们的手位置一致。综合这些结果，我们得出结论，在乒乓球游戏中对视觉运动延迟的适应选择性地影响了目标导向动作的执行，当动作指向视觉目标时会导致动作过度和感知偏差，而当没有此类目标时则不会。最近的研究表明，在没有视觉反馈的情况下，对视觉运动延迟的适应会导致动作过度伸展，这表明视觉运动延迟是利用当前状态信息来表征的。我们报告说这种适应也会影响感知。重要的是，运动和感知效应都对用于执行朝向视觉目标的目标导向动作的表征具有选择性。
