1 / 15

Understanding Motor Skills

Understanding Motor Skills. Introduction Focus: Response mechanism of the human body as the output of information processing “input—mediation—output” Knowledge bases from:. Biomechanics Kinesiology Psychology Neuroscience. Terms to Describe Body Movements. Three Anatomical Planes:

lang
Download Presentation

Understanding Motor Skills

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Understanding Motor Skills • Introduction • Focus: • Response mechanism of the human body as the output of information processing • “input—mediation—output” • Knowledge bases from: Biomechanics Kinesiology Psychology Neuroscience

  2. Terms to Describe Body Movements • Three Anatomical Planes: • Flexion — • Extension — • Abduction — Frontal, Sagittal, Transverse A movement of a segment of the body causing a decrease in the angle of the joint A movement in the opposite direction of flexion which causes an increase in the angle at the joint A movement of a body segment in the lateral (frontal) plane away from the midline of the body

  3. Terms to Describe Body Movements • Adduction — • A movement of a body segment • toward the midline as when moving • the arm from the outward horizontal • position downward to the vertical • position. • Rotation — • Circumduction — A movement of a segment around its own longitudinal axis A circular or cone-like movement of a body segment

  4. Control & Acquisition of Motor Responses • Skill - the ability to use the correct muscles with the exact force necessary to perform the desired response with proper sequence and timing (Jensen, Schultz, and Bangerter, 1983) • Three Aspects: • spatial-temporal precision • “doing the right thing at the right time” • adaptability to changing • environmental conditions • consistency of action from occasion to occasion

  5. Types of Responses • Discrete Movements — • Repetitive Movements — • Sequential Movements— involving a single reaching movement to a stationary target; may or may not be visually guided involving a repetition of a single movement to a stationary target(s) involving discrete movements to a number of stationary targets regularly or irregularly spaced

  6. Types of Responses • Continuous movements — • Static positioning — involving movements that require muscular control adjustments of some degree during the movement consisting of maintaining a specific position of a body member for a period of time

  7. Sensory Feedback • motor responses can be influenced by both internal and external feedback • Close-loop servocontrol model • feedback — ( high impact ) • feedforward — sensory information that is available during or after the motor response sensory info that is available prior to the action that regulates and triggers coordinated responses

  8. Sensory Feedback • Sources of feedback • Kinesthesis (proprioception) • Receptors: • Muscle spindle for muscle length and rate of change • Golgi tendon organ for muscle force • Vision • Sound

  9. Speed of Movements Total Response Time = Reaction time —>the time from onset of a signal calling for a response until the beginning of the response + Movement time —>the time from the beginning of the response until its completion

  10. Reaction Time • - under ideal conditions, simple reaction time is between 150 - 200 msec • Influences on reaction time : • stimulus modality • stimulus detectability • preparedness or expectancy of a signal • age • spatial frequency • stimulus location

  11. Reaction Time Reaction Time • Choice reaction time • this is an issue when one of several possible stimuli are presented, each of which requires a different response. • Some influences on choice reaction time : • compatibility between stimuli and • responses • practice • warning • type of movement • more than one stimulus

  12. Movement Time • Direction of Movement • this affects the time to make the movement • controlled arm movements that are primarily based on a pivoting of the elbow take less time than those that require a greater degree of upper-arm and shoulder action • Distance and Accuracy Required • Fitt’s Law

  13. Movement Time Fitt’s Law • Fitt’s Law holds for : • movements of the head • movements of the feet • movements of the fingers • and more MT = a + b log2 (2D/W) • where : • MT = movement time • a,b = empirically derived constants, • movement type dependent • D = distance of mvmt from start to target center • W = width of target

  14. Accuracy of Movements • Often accuracy of a response is of greater importance than the response time, within limits • —Location • close-in, straight-ahead, below- shoulder positions reduce error (Fig. 9-11) • —Distance • overshooting short distance and undershooting long distance • (Fig. 9-12) • —Speed of Movement • Schmidt’s Law: W = a+b(D/MT)

  15. Exercise • “I saw her friend Jane today” • (1) Write the sentence 10 times with your preferred hand • (2) Write the sentence holding the pen • in your RIGHT HAND • in your LEFT HAND • in your MOUTH • What can you learn from this experiment?

More Related