Classifying & Measuring motor skills

Classification of motor skills

Assessment of sustained change in motor skill ability differs depending on the nature of movement & the perceptual attributes of the skill

Nature of movement

Skilled behaviour must have a start & end point where an individual affects the outcome

Perceptual attributes of skill

Now stable & predictable is the environment during skill evaluation

Skills basal on nature of movement and classified into

Discrete serial & continuous

Discrete motor skill

Have a definitive start & end to the skill, where the outcome cant be affected by individual; one movement like a free throw

Serial motor skills

Have a defined start & end but require the correct sequencing of multiple discrete skills to accomplish I doing a lay up

Continuous motor skills

Discrete on serial actions ave performed continuously until the performer chooses to stop:

Influencing out come while moving ; swimming

Skills based upon perceptual attributes are classified into

Closed 4 open motor skills

Closed motor skills

Skills performed in a predictable & constant environment from the time a skill starts to the time skill is complete

Open motor skills

Skills performed in a varied unpredictable environment where environment could change while skill is being performed

How to quantify the degree of the skill exhibited

Translate motor skill concept into something measurable; start with a concept then operationalize it & use that to measure skill

Conceptual definition

Represents the general notion / abstract idea of how a skill should beperformed

Operational definition

Identifies the observable & measurable components used to represent a motor skill

Assessment of motor skill performance must be

Valid, reliable & sensitive to different levels of ability

Valid

A measure accurately assesses the motor skill performance or learning outcome it's intended to assess

Reliability

Measure produces consistent results when repeated under the same conditions

Sensitive

Measures ability to detect meaningful changes in performance or learning including relatively small declines &

Improvements

A useful measure of motor learning must be

Valid (accurate). Reliable (consistent) & sensitive ( able to detect meaningful change

‘ Measures of motor skill ability

Variables used to quantify how effectively an individual performs a motor skill

Measures of motor skill ability include

Measures of precision, speed, movement magnitude & effort

Measures of precision

Constant error, variable error, total variability, absolute error, time on target, root mean square error ( RMSE )

Measures of speed

Response time, reaction time, movement time

Measures of movement magnitude

Distance & deviation

Measures of effort

Dual - task cost

Discrete & serial skill measures of precision

Capture performance @ a given point in time using Constant error, variable error, total error, absolute error

Constant error

Bias to produce your typical outcome; average error across trials

Variable error

Consistency of producing your typical outcome

Total error

Combination of bias + consistency

Absolute error

Variability & consistency around each outcome & the target; accuracy relative to the target across trials

Continuous skills measures of precision

Use time on target & roof mean square error to summarize performance over time

Time on target

Time the participant was able to stay within an acceptable range of a target

Root mean square error (RMSE)

Average deviation from the target across time; doesn't distinguish direction of deviation (below/above)

Time-based measures useful for

Assessing performance in discrete motor skills

Time based measures include

Response time, reaction time & movement time

Response time

Time from stimulus onset ( cue to begin the skill) → movement completion

Reaction time

Time from stimulus onset required to process information & transmit the signals to initiate muscle movement

Movement time

Time from muscle onset to movement completion reflecting the demands of coordinating & executing a movements

Reaction time consists of

Premotor RT & motor RT which corresponds to the neural activity before the onset of muscle movement

Some skilled motor behaviours are better assessed using

Distance or deviation from a reference point

Dual task cost

Decline in performance because effort must be allocated to a concurrent task

Dual-task cost assumes

The nervous system has a fixed pool of resources to support ongoing processes that support behaviour: resources allocated to e process can't be simultaneously allocated to another

Decreasing dual task cost

Greater motor skill ability is associated with requiring less mental effort to perform that shill