General categories of performance measurements
1. Performance outcome measures
2. Performance production measures
Outcome measures
Indicates the outcome or result of performing and motor skill
Production measures
Indicates performance of specific aspects of motor control systems during performance (i.e. EMG)
Reaction time
Indicates how long it takes a person to prepare and initiate a movement
Electromechanical delay
What goes on before movement occurs
Simple RT
One signal-one response
Choice RT
More than one signal-each signal has a specific response
Discrimination RT
More than one signal-only one response
Pre-motor time
"Quiet interval"; time between onset of stimulus and beginning of activity
Motor time
Interval of time from initial increase in muscle activity until the actual limb movement
Pre-motor time interval
Receive signal from environment "go", transmit to CNS, process signal, transmit to muscles (motor command)
Motor time interval
Time lag of receiving motor command to tension generation; isometric to isotonic response, overcome intertia of limb
Consistency (error measure)
"All over the map", lack of basic skill acquisition
Bias (error measure)
Adapting to demands of environment- off consistently
Absolute error
Difference between the performance on each trial and the criterion for each trial
Constant error
Algebraic value of AE
Variable error
The standard deviation of the constant error scores; index of consistency
Kinesthetic awareness and joint position sense
Kinesthetic awareness
Threshold to detect passive motion
Joint position sense
Reproduction of positioning
Radial error
General accuracy measure for 2-D; use when outcome of performing a skill requires accuracy in the X and Y direction (result is hypotenuse)
Root-Mean Squared Error
Common accuracy measure for continuous skills
Task failure
Inability to sustain task at target force; decreased max voluntary contraction
Description of motion without regard to force or mass; displacement, velocity, acceleration.
force as a cause of motion; push or pull
Internal force
Comes from muscle activation
External force
Applied to limb segment
InDirect force measurement
Analyzing forces through kinemtaics
Electromyography; recording of muscle electrical activity; uses superficial or indwelling electrodes
Electroencephalography; measures brain electrical activity
Positron Emission Topography; neuroimaging technique that measures blood flow in the brain; several serial snap shots; can visualize tumors over time
Functional Magnetic Resonance Imaging; neuroimaging technique that measures blood flow changes in the brain by detecting blood oxygenation characteristics; uses radio waves and strong magnetic field to provide clear and detailed pictures of internal organs and tissues; measures tiny metabolic changes that take place in an active part of the brain
Trans cranial Magnetic Stimulation; magnetic fields created by passing a current through a hand-held coil; noninvasive way to excite neurons; can stimulate motor part of brain; able to influence many brain functions
Relative phase
Index of the coordination between 2 limb segments or limbs during the performance of a cyclic movement