Randomizing visual feedback in manual aiming: reminiscence of the previous trial condition and prior knowledge of feedback availability

Abstract

A trial-by-trial analysis was used to systematically examine the influence of switching visual conditions on visual feedback utilization for a manual aiming movement. In experiment one, vision was randomly manipulated from trial to trial with no more than four consecutive trials in the same visual condition. In experiment two, participants were provided with certainty of visual feedback availability prior to every trial. Results of both studies revealed that movement endpoint variability was most associated with visual feedback availability on the previous trial. Furthermore, correlation analyses comparing movement trajectory at 25, 50 and 75% with movement end (i.e. 100%) revealed that the efficiency of online corrections also depends on the availability of visual feedback on the previous trial. These results suggest that the accuracy of an aiming movement is highly dependent on processing of offline visual information from the preceding trial.

The Influence of Visual Feedback and Prior Knowledge About Feedback on Vertical Aiming Strategies

“…This occurred independent of vision condition or movement direction. The advantage probably stems for the fact that within a block of trials, information (visual and/or proprioceptive) associated with trial N can be more effectively used to plan and control trial N + 1 (Cheng et al, 2008;Elliott et al, 2004). The absence of any important interactions between vision condition and order could reflect the fact that the movement times in this experiment were in the vicinity of 500 ms.…”

“…One of the empirical problems with manipulating vision during the movement trajectory is determining whether or not any differences in aiming accuracy (particularly under blocked feedback conditions) are due to visual online regulation during each individual trial or an advantage associated with visual feedback about endpoint error on trial N being used to adjust feedforward planning of trial N + 1 (Cheng, Luis & Tremblay, 2008;Zelaznik et al, 1983). In an attempt to clarify the relative contribution of online and terminal feedback we introduced a further manipulation.…”

“…Manipulating access to terminal visual feedback about movement outcome was based on the notion that visual outcome information from trial N is important for the planning of trial N + 1 (Cheng et al, 2008;Elliott et al, 2004;Zelaznik et al, 1983) and, in the form of terminal feedback, may offset the effect of not having access to visual information as a trial unfolds (i.e., the no vision condition in Experiment 1).…”

Quantifying online visuomotor feedback utilization in the frequency domain

“…Evidence for this assertion has come from the finding that performance is maximized when the availability of visual feedback is scheduled in a blocked manner, as compared to a randomized schedule (i.e., Elliott & Allard, 1985). In addition, both the relative certainty of the availability of feedback (i.e., Zelaznik et al, 1983) and the availability of vision on preceding trials (i.e., Cheng, Luis, & Tremblay, 2008) have been shown to influence endpoint accuracy across reaches. Thus, changes in reaching performance, which could otherwise be erroneously attributed to online feedback utilization, could theoretically come about through offline changes in performance.…”

We’re talking about feedback … aren’t we?

“…I know that it is the temporal constraints associated with the evaluation of concurrent action-related feedback that characterize the corrections we can make to our actions online, while they are unfolding (Woodworth 1899). And I also know that feedback about the outcomes of our actions-how what we have done looks, sounds, and feels-helps us re-parameterize our systems for our subsequent attempts at the action (Cheng et al 2008).…”