An optimal velocity for online limb-target regulation processes?

Exp Brain Res. 2017 Jan;235(1):29-40. doi: 10.1007/s00221-016-4770-x. Epub 2016 Sep 12.


The utilization of visual information for the control of ongoing voluntary limb movements has been investigated for more than a century. Recently, online sensorimotor processes for the control of upper-limb reaches were hypothesized to include a distinct process related to the comparison of limb and target positions (i.e., limb-target regulation processes: Elliott et al. in Psychol Bull 136:1023-1044. doi: 10.1037/a0020958 , 2010). In the current study, this hypothesis was tested by presenting participants with brief windows of vision (20 ms) when the real-time velocity of the reaching limb rose above selected velocity criteria. One experiment tested the perceptual judgments of endpoint bias (i.e., under- vs. over-shoot), and another experiment tested the shifts in endpoint distributions following an imperceptible target jump. Both experiments revealed that limb-target regulation processes take place at an optimal velocity or "sweet spot" between movement onset and peak limb velocity (i.e., 1.0 m/s with the employed movement amplitude and duration). In contrast with pseudo-continuous models of online control (e.g., Elliott et al. in Hum Mov Sci 10:393-418. doi: 10.1016/0167-9457(91)90013-N , 1991), humans likely optimize online limb-target regulation processes by gathering visual information at a rather limited period of time, well in advance of peak limb velocity.

Keywords: Online control; Perception; Reaching; Target jump; Vision.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adolescent
  • Adult
  • Analysis of Variance
  • Biomechanical Phenomena
  • Female
  • Humans
  • Judgment
  • Male
  • Movement / physiology*
  • Psychomotor Performance / physiology*
  • Time Factors
  • Upper Extremity / physiology*
  • Visual Perception / physiology*
  • Young Adult