The relative contributions of internal motor cues and external semantic cues to anticipatory smooth pursuit

Abstract

Smooth pursuit eye movements anticipate the future motion of targets when future motion is either signaled by visual cues or inferred from past history. To study the effect of anticipation derived from movement planning, the eye pursued a cursor whose horizontal motion was controlled by the hand via a mouse. The direction of a critical turn was specified by a cue or was freely chosen. Information from planning to move the hand (which itself showed anticipatory effects) elicited anticipatory smooth eye movements, allowing the eye to track self-generated target motion with virtually no lag. Lags were present only when either visual cues or motor cues were removed. The results show that information derived from the planning of movement is as effective as visual cues in generating anticipatory eye movements. Eye movements in dynamic environments will be facilitated by collaborative anticipatory movements of hand and eye. Cues derived from movement planning may be particularly valuable in fast-paced human-computer interactions.

LRP predicts smooth pursuit eye movement onset during the ocular tracking of self-generated movements

“…3A), and reduced delay at reversal. This largely confirmed the findings of earlier studies showing more accurate ocular tracking of self-generated motion relative to tracking of external motion (Mather and Lackner 1980;Ross and Santos 2014) or tracking of passive movements (Steinbach 1969;Steinbach and Held 1968;Vercher et al 1995Vercher et al , 1996. As a novel manipulation in our paradigm, we varied the predictability of the dot motion in the control conditions.…”

“…However, in the current experiment we found that the LRP is strongly predictive of the start of the smooth pursuit eye movements. This explains why the smooth pursuit of self-motion has less lag and fewer saccades compared with the pursuit of external motion, as we observed in experiment 1 and previous studies (Gauthier and Hofferer 1976;Mather and Lackner 1980;Ross and Santos 2014;Scarchilli and Vercher 1999;Steinbach 1969;Steinbach and Held 1968;Vercher et al 1995).…”

“…Finger tracking is a classical paradigm in the investigation of eye-hand coordination, the most common finding being that ocular tracking of self-motion is enhanced compared with the tracking of externally driven motion (Mather and Lackner 1980;Ross and Santos 2014;Steinbach, 1969;Steinbach and Held 1968;Vercher et al 1995Vercher et al , 1996. In the present study we replicate the classical finding, showing that finger tracking is better in terms of both reduced saccade rate and decreased latency, and we extend it by demonstrating that ocular tracking of externally driven motion is not quite as good as finger tracking, even when the motion is completely predictable in terms of both onset time and kinematics.…”

Davida Teller Award Lecture 2013: The importance of prediction and anticipation in the control of smooth pursuit eye movements

“…One type of cue to the direction of future motion, which we may encounter frequently in natural situations, is the internal signal derived from our own motor commands whenever we control the motion of a target by ourselves. This situation was recently studied by Ross and Santos (2014).…”

“…An example is shown in Figure 8, which shows intersaccadic eye velocities were slow during a task that required guiding a mouse cursor through a displayed maze [Zhao & Marquez, 2013].) Ross and Santos (2014) studied the role of the motor signals used to control a target that was moved along the same cued or uncued paths illustrated in Figure 2. In their experiment a mouse was used to control the horizontal trajectory of motion of the target (the vertical motion was controlled by the software).…”