Table 2 Examples of interlimb coordination-related protocols and measures used in motor control neuroscience
Paradigm | Methods | Reported measure (s) of interlimb coordination |
|---|---|---|
Circle or ellipse drawing | • Trace large circles with finger tips on horizontal plane • Pacing with auditory signal • 4 conditions: both clockwise, both counter-clockwise, both inwards, and both outwards [26] | • Difference in uniformity of relative tangential angle • Difference in circular variance • Difference in frequency deviation • Differences in variability of frequency • Uniformity of discrete relative phase • Aspect ratio • Difference in spatial variability |
• Trace circles by moving crank arms on horizontal plane • Increasing tracing speed, from slow to fast • Distortion of visual feedback of one arm • 2 conditions: mirror symmetric starting at the same points or on opposite sides of circle [13] | • Relative angle | |
• Trace large circles with finger tips on horizontal plane • Pacing with visual signal; 2 frequencies • 2 conditions: both inwards, and both counter-clockwise • Continuous tracing or with pause between each completed circle [84] | • Difference in uniformity of relative tangential angle • Aspect ratio • Difference in spatial error | |
Bilateral point-to-point movements | • Forward movements in horizontal plane • Targets stationary or moved when hand exceeds threshold velocity • Targets visually misrepresented closer or farther away from true target location • Gaze on non-target location [27] | • Difference in endpoint error • Difference in movement duration • Difference in size of on-line adjustment • Difference in onset of on-line adjustment • Lateral spatial separation |
• Forward or outward movements in horizontal plane • Targets stationary • Targets visually represented directly or through symbolic cues (i.e., letters) [56] | • Difference in reaction time • Difference in movement time | |
• Draw back-and-forth lines • a vertical line task in the left limb, and a star task in the right limb (either separately or simultaneously) • Movements were restricted to the shoulder and elbow [85] | • Mean and standard deviation of orientation of each line drawing with respect to the horizontal reference position | |
Bilateral (physically) coupled movements | • Forward and backward movements in horizontal plane • Hands on ends of rigid bar that rotates around midpoint | • Balance error • Average stopping field |
• Movements in horizontal plane • Hands on ends of stiff bar (can elongate or compress) virtually rendered between manipulandums • Transport virtual ball, that can roll along the bar, to static targets [88] | • Absolute tilt • Difference in reaction time • Change in bar length • Difference in hand speed • Difference in hand speed peaks • Difference in hand path length |