Pursuit Rotor Task

Background

The Pursuit Rotor Task is a classic behavioral test to measure visual-motor tracking, hand-eye coordination, and procedural learning. The original apparatus for the rotary pursuit task was designed by psychologist Wilhelmine Koerth in 1922 who sought to design a task to help find applicants of high hand-eye coordination aptitude for specialized, dexterous labor jobs. The device consisted of a mechanical turntable that spun a small disk in a circle at a constant speed. The task was to continuously keep a handheld device on the disk. Beyond measuring baseline hand-eye coordination, the tool was further built to observe how people learn over time. By keeping the target's path predictable and its speed uniform, researchers could map out clean learning curves based on how quickly an individual's off-target errors decreased over repeated trials.

Modern computerized implementations of the task use a digital dot or circle that moves along a circular path on a screen at constant speed. The user tracks it using the computer mouse, joystick, finger or stylus pen. While the task is no longer used for vocational purposes, researchers use the Pursuit Rotor task to track the progression of certain neurodegenerative diseases such as Parkinson's or Huntington's or check improvements for stroke patients and those suffering from Traumatic Brain Injury (TBI). In addition, like the Adaptive Tracking Task, the Pursuit Rotor Task is used for pharmaceutical research and studies on sleep deprivation.

Task Procedure

The Millisecond Pursuit Rotor uses (by default) an active game canvas of 12cm x 12cm (Note: this can be easily adjusted). The radius of the track as well as the radius of the disc and all text stimuli are defined in proportion to the height of the active canvas. The active canvas presents in gray; the inactive portion of the screen presents in black. If the script is run on a screen that does not support these dimensions, the script alerts participants and then aborts.

The Millisecond Pursuit Rotor runs 4 trials that last 10 seconds each. The task records the screen coordinates of the cursor/finger/stylus and disk about every 16.7ms while the disk is rotating. Once the task is started, participants are introduced to the track set-up and the yellow target disk. To start each trial, participants must click on (touch) the yellow circle which begins rotating around the track immediately. Participants are instructed to continuously keep their cursor/finger/stylus pen on the yellow disk. A tracking alert stimulus that turns red or green depending on whether participants are off or on the target, respectively, is shown in the center of the track. Once the disk has finished its 10 second rotation, a trial ends, and the next one can be started by button press. At the end of the task, optional performance feedback is provided to participants.

What it Measures

The Pursuit Rotor task measures visuomotor coordination and vigilance

Psychological domains

• Visuomotor Coordination: The ability of the brain, eyes, and body to work together on a task
• Vigilance: Ability to maintain focus on a continuous repetitive task over a long time.
• Procedural Memory: Ability to encode, store, and automate a motor skill over repeated trials

Main Performance Metrics

• Off Target Time: time (in ms) spent OFF the target disk
• Recovery Duration: the mean duration (in ms) that participant needed to return to the target after losing it
• Distance from Target Center: the mean distance (in mm) of the response coordinates and the center of the target disk

Psychiatric Conditions

The following patient groups have been tested with the Pursuit Rotor Task

• Parkinson’s Disease (PD)
• Mild Cognitive Impairment (MCI)
• Korsakoff’s Syndrome
• Amnesia
• Schizophrenia
• Mood Disorders
• Pharmaceutical Studies on Healthy Adults

References

Search Google Scholar for peer-reviewed, published research using the Inquisit Pursuit Rotor Task.

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Adams, J. A. (1952). Warm-up decrement in performance on the pursuit-rotor. The American Journal of Psychology, 404-414.

Ammons, R. B. (1955). Rotary pursuit apparatus: I. Survey of variables. Psychol. Bull, 52, 69-76.

Nagasawa, Y., Demura, S., & Kitabayashi, T. (January 01, 2004). Concurrent validity of tests to measure the coordinated exertion of force by computerized target pursuit. Perceptual and Motor Skills, 98, 2, 551-60.

Peters, K. R., Smith, V., & Smith, C. T. (January 01, 2007). Changes in sleep architecture following motor learning depend on initial skill level. Journal of Cognitive Neuroscience, 19, 5, 817-29.

Piper, B. J. (2010). Age, handedness, and sex contribute to fine motor behavior in children. Journal of Neuroscience Methods. doi:10.1016/j.jneumeth.2010.11.018.

Hatakenaka, M., Miyai, I., Mihara, M., Yagura, H., & Hattori, N. (January 01, 2012). Impaired motor learning by a pursuit rotor test reduces functional outcomes during rehabilitation of poststroke ataxia. Neurorehabilitation and Neural Repair, 26, 3.)