Article

Continuous visual control of interception

Research Institute MOVE, Faculty of Human Movement Sciences, VU University Amsterdam, Van der Boechorststraat 9, NL-1081 BT Amsterdam, The Netherlands.
Human movement science (Impact Factor: 1.6). 02/2011; 30(3):475-94. DOI: 10.1016/j.humov.2010.12.007
Source: PubMed

ABSTRACT

People generally try to keep their eyes on a moving target that they intend to catch or hit. In the present study we first examined how important it is to do so. We did this by designing two interception tasks that promote different eye movements. In both tasks it was important to be accurate relative to both the moving target and the static environment. We found that performance was more variable in relation to the structure that was not fixated. This suggests that the resolution of visual information that is gathered during the movement is important for continuously improving predictions about critical aspects of the task, such as anticipating where the target will be at some time in the future. If so, variability in performance should increase if the target briefly disappears from view just before being hit, even if the target moves completely predictably. We demonstrate that it does, indicating that new visual information is used to improve precision throughout the movement.

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Available from: Jeroen Smeets
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    • "When interacting with moving objects, they ignore the moving objects' accelerations for controlling various aspects of their movements (Benguigui & Bennett, 2010;Lee, Young, Reddish, Lough, & Clayton, 1983;Port, Lee, Dassonville, & Georgopoulos, 1997). In many of the cases in which acceleration is not evidently ignored, the apparent use of information about the object's acceleration might just reflect the fact that movements are continuously adjusted on the basis of continuously updated estimates of the object's position (Brenner & Smeets, 2011;Dubrowski & Carnahan, 2002) and velocity (Brenner, de Lussanet, & Smeets, 2002). When the acceleration of horizontally moving targets that people are trying to intercept is varied randomly across trials, people make systematic errors that correspond with ignoring the acceleration during the delay between when visual information reaches the eye and when the arm responds to such information (Brenner & Smeets, 2015). "
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    • "The target moved for considerably longer than 116 ms, but assuming that the tapping movement is continuously adjusted (Brenner & Smeets, 2011), we would only expect to see effects of anything that is ignored during the final part of the movement, when sensorimotor delays prevent direct feedback-based correction. A sensorimotor delay of about 116 ms is reasonably consistent with the literature (Brenner & Smeets, 1997; Carlton, 1981; Oostwoud Wijdenes et al., 2011). "
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    • "Experimental evidence of visual control in the course of action has shown for arm and hand movements (e.g. grasping a static target (Goodale, 2011); intercepting a moving target (Brenner & Smeets, 2011)), as well as driving (Wallis et al., 2007). "
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