Related Experiment Video
Updated: Mar 15, 2026
09:27
An Emerging Target Paradigm to Evoke Fast Visuomotor Responses on Human Upper Limb Muscles
Published on: August 25, 2020
4.8K
An optimal velocity for online limb-target regulation processes?
Luc Tremblay1,2,3, Valentin A Crainic4, John de Grosbois4
1Faculty of Kinesiology and Physical Education, University of Toronto, Toronto, ON, Canada. luc.tremblay@utoronto.ca.
Experimental Brain Research
|September 14, 2016
Summary
Humans optimize limb-target regulation during reaching movements by using visual information at an optimal limb velocity. This suggests a specific, limited time window for visual feedback, not continuous processing.
Area of Science:
- Motor Control
- Human Movement Science
- Perception and Cognition
Background:
- Visual information is crucial for controlling voluntary limb movements.
- Online sensorimotor control of upper-limb reaches may involve distinct limb-target regulation processes.
- Previous models suggested pseudo-continuous online control.
Purpose of the Study:
- To test the hypothesis of distinct limb-target regulation processes in online movement control.
- To identify the optimal timing for visual feedback during reaching movements.
- To investigate if visual information gathering is limited to specific movement phases.
Main Methods:
- Participants performed reaching movements with brief visual feedback (20 ms) presented at specific limb velocities.
- Experiment 1 assessed perceptual judgments of endpoint bias (undershoot/overshoot).
- Experiment 2 examined endpoint distribution shifts after imperceptible target jumps.
Main Results:
- Limb-target regulation processes were most effective at an optimal limb velocity (around 1.0 m/s).
- This optimal velocity occurred between movement onset and peak limb velocity.
- Visual feedback timing, rather than continuous processing, appears critical.
Conclusions:
- Online limb-target regulation is optimized at a specific "sweet spot" velocity.
- Humans likely gather visual information during a limited time window for optimal control.
- This challenges continuous online control models, suggesting a more temporally constrained visual feedback mechanism.
Related Concept Videos
01:24Relative Motion Analysis - Velocity
890
A stroke engine has a slider-crank mechanism that converts rotational motion from the crank into linear motion of the slider or vice versa. This mechanism consists of three main parts: the crank, the connecting rod, and the slider.
When an external force is exerted, it sets the crank into a rotational movement. This, in turn, instigates the motion of the connecting rod, leading to what is referred to as a general plane motion. This process involves two key points - point A on the connecting rod...
When an external force is exerted, it sets the crank into a rotational movement. This, in turn, instigates the motion of the connecting rod, leading to what is referred to as a general plane motion. This process involves two key points - point A on the connecting rod...
890
01:18Velocity of an Object
250
Understanding how an object moves along a path requires distinguishing between motion over a time span and motion at a precise moment. A useful example is a vehicle traveling along a straight and level path, where its position at any given time is known. The initial step in analyzing this motion is to measure how far the vehicle travels over a fixed time period. This measurement, called average velocity, is computed by dividing the total change in position by the duration over which the change...
250
01:12Average Velocity
25.6K
To calculate the other physical quantities in kinematics, we must introduce the time variable. The time variable allows us not only to state the position of the object during its motion, but also how fast it is moving. The speed at which an object is moving is given by the rate at which the position changes with time. For each position xi, we assign a particular time ti. If the details of the motion at each instant are not important, the rate is usually expressed as the average velocity. This...
25.6K
01:12Average and Instantaneous Velocity Vectors
9.0K
To calculate other physical quantities in kinematics, the time variable must be introduced. The time variable not only allows us to state where an object is (its position) during its motion, but also how fast it’s moving. The speed at which an object is moving is given by the rate at which the position changes with time. For each position, a particular time is assigned. If the details of the motion at each instant are not important, the rate is usually expressed as the average velocity v.
9.0K
01:13Velocity and Position by Integral Method
8.8K
If acceleration as a function of time is known, then velocity and position functions can be derived using integral calculus. For constant acceleration, the integral equations refer to the first and second kinematic equations for velocity and position functions, respectively.
Consider an example to calculate the velocity and position from the acceleration function. A motorboat is traveling at a constant velocity of 5.0 m/s when it starts to decelerate to arrive at the dock. Its acceleration is...
Consider an example to calculate the velocity and position from the acceleration function. A motorboat is traveling at a constant velocity of 5.0 m/s when it starts to decelerate to arrive at the dock. Its acceleration is...
8.8K
01:07Time-Domain Interpretation of PD Control
429
Proportional-Derivative (PD) control is a widely used control method in various engineering systems to enhance stability and performance. In a system with only proportional control, common issues include high maximum overshoot and oscillation, observed in both the error signal and its rate of change. This behavior can be divided into three distinct phases: initial overshoot, subsequent undershoot, and gradual stabilization.
Consider the example of control of motor torque. Initially, a positive...
Consider the example of control of motor torque. Initially, a positive...
429