Exam #2 Flashcards
Generalized Motor Program (GMP)
- theory
- movements can be varied along certain dimensions
ex) slow/fast, louder/softer
Motor Program
prestructured set of movement commands that defines and shapes the movement
Open Loop Control
Input, Executive, Effector, Output
- no feedback or comparator
- no modifications while in progress
- inflexible
- most effective in stable environments
Open Loop Example
-traffic light continues to go even if an accident takes place
Motor Program determines
- which muscles to contract
- in what order
- when
- for how long
Practice helps build motor programs that are:
- more stable
- more precise
- longer-operating
- combo of those
Practice stored in
long term memory. must be retrieved and prepared for initiation during response programming
Most tasks are:
a mix of open and closed loop system
Reaction Time is longer with:
- more info to process
- more limbs must be coordinated
- duration of movements becomes longer
Startle Reaction
unexpected event causes a severe reaction
-accompanied by contraction of face/neck and protective movements of upper limbs
Startle Reaction motor program
- executive prepares motor program in advance
- signal released by executive is hastened
- executor may be bypassed altogether
Roles of Open Loop (muscles)
determine:
- forcefulness
- duration
- which ones contract
Roles of Open Loop
- organize degrees of freedom of muscles and joints
- initiate postural adjustments for support of action
- modulate reflexive pathways to ensure movement goal is met
Anticipatory Adjustments
motor system compensates before the movement is made
Generalized Motor Program Theory
- stored pattern
- stored program is adjusted at time of movement execution
- allows action to be changed slightly to meet environmental demands
invariant features of motor program
make a pattern appear the same time after time
surface features of a motor program
aspects that allow change in a movement
GMP Movement Production
- stimulus id phase
- response selection phase
- GMP retrieved from long term memory
- movement programming stage (motor program is prepared)
movement parameters
- speed of movement
- amplitude
- limb used
invariant features of a GMP
- relative timing (rhythm) (timing preserved)
- classes of movements (“throwing”)
GMP Parameters
- movement time
- movement amplitude
- effectors (movement can be modulated by using a different limb to produce same action)
Fitt’s Law
movement time is consistent whenever the ratio of the movement amplitude to target width remains constant
- MT increases as ratio of A to W increases
- long movements+wide targets = short movements + narrow targets
haste makes waste?
accuracy decreases as speed increases
speed accuracy trade off
people tend to give up speed in order to trade speed for accuracy
slower movements are more accurate
- more time to detect errors and make corrections
- MT increases when # of corrections needed increases
Linear speed accuracy trade off
if movement distance increases, MT can be decreased and accuracy can be maintained during rapid tasks
sources of error in rapid movements
-force is inconsistent over successive trials
ex- hitting a nail with hammer
-as MT decreases, forces exerted must increase
-contraction force increases = more variability
-movement inaccuracy increases as MT decreases
exceptions to speed accuracy trade off
- very forceful movements are consistent spatially
- force variability levels off as force approaches max
-temporal accuracy (decrease MT = decrease error)
Bimanual Aiming tasks
- MT and kinematics for both limbs are determined by a joint command
Continuous Bimanual Tasks
controlling continuous movement of two limbs, each with its own spatial or temporal goal
ex) rubbing head while patting tummy
differential method
-differences between and among people
ability
a fundamental characteristic of different individuals that tends to underlie particular skills
-largely inherited and unmodifiable by practice
individual differences
- stable & enduring
- measurable characteristic
- or in terms of performance
skill
- proficiency at a particular task
- can be modified by practice
- countless in number
ability sets limits for performance
- body type
- personality
General Motor Ability Hypothesis
- single inherited motor ability is assumed
- underlies all movements
- “all around athlete” good at all motor tasks
Henry’s Specificity Hypothesis
If person does well on motor task A, they will do well on motor task B
-assumed strong general motor ability
Correlations among various skills
- unless tasks are very similar, no correlation success during skills
- there are many abilities vs single general motor ability
Types of Motor Ability
- reaction time
- response orientation(quick choices among a # of alternative moves)
- speed of movement
- finger dexterity
- manual dexterity
- response integration
- physical fitness
Superability
- may be a very weak general factor underlying most movement skills
- gives slight advantage
criterion skill
ultimate skill in which person is interested
-how to find someone with the “right” abilities for a particular sport
advantages of prediction
- novices can be directed
- reduce training time
- training more focused
Fleishman & Hempel Study
- pushing switches in response to lights (RT)
- discrimination RT is fairly large contributor to performance, increases from 20% to 40%
- become less reliant on abilities
- performance depended on different abilites at the start of practice (spatial relations) than at the end (rate of arm movement)
Motor Learning Theory
set of ideas used to explain the acquisition and modification of movements
-several theories
Motor Learning
process of acquiring the capability for skilled action
- results from experience or practice
- inferred based on behavior, not measured directly
- produces permanent behavior changes
learned behavior
- evident on a retention test
- skill can be generalized
most effective practice conditions lead to
accurate performance in a novel version/scenario/setting
goals of practice and training
long-term retention
generalizability
task learning resistant to altered contexts
Intrinsic feedback
- info gathered through an individuals available senses
- occurs as the person is performing the movement skill
- compared to a learned reference of correctness
extrinsic feedback
- provided verbally to the learner (by another)
- supplements intrinsic feedback
- can be provided as knowledge of results or of performance
Knowledge of Results
- postaction info feedback
- about the movement outcome
- provides error and modifications
- helps keep the learner alert and motivated
Knowledge of Performance
- post-action info about the correctness of movement pattern
- directed towards improving the movement pattern
Strongest influence on motor learning
practice
massed practice
- continuous practice with no rest periods
- or practice sessions during which the practice time is longer than the rest period between practices
distributed practice
- interspersed practice
- more time spent resting between practice sessions
- enhances performance and learning more than massed practice (for continuous tasks)
whole-task practice
-practicing the entire activity
part-task practice
- practicing components of the activity
- unless the component parts are subskills of each other or natural components of the task, part practice is not as beneficial as whole practice
mental practice
performing or running through the activity in one’s mind without physical practice
- can’t replace physical practice but can help with tasks requiring accuracy
- triggers neural circuits underlying previously learned physical movement sequences
constant practice
practicing the same movement task in the same way for every trial
-no variations in task conditions
varying practice
- altering the conditions of the task across practice trials
- more effective than constant practice
schedule of practice
- how different tasks practiced together are grouped or ordered in a session
- multitask practice
Contextual Interference Effect
blocked practice
- learner learns better during the practice session
- less retention/memory for the skills later
Contextual Interference Effect
random practice
- more controlled/strategic cognitive processing
- more opportunities for changing the action plan
- may perform poorly during practice but
- more cognitive efforts = more memory and generalization
most successful learning
variety of tasks in a nonsystematic way
physical guidance is
no more effective than allowing a learner to engage in unguided practice
organized movement patterns
movement synergies or coordinative structures
children with movement difficulties
- may not solve problems in a typical way
- extrinsic sources of feedback that focus a child’s attention on specific aspects of the task and sensory cues may be important
- little research
optimal feedback control
- accurate prediction of consequences of motor demands
- combine predictions with sensory feedback to form judgment
- use estimate to adjust the gains of sensorimotor feedback loop
skilled athletes
- performance continues to improve with task-relevant practice over indefinitely
- rate of improvement declines over time
factors important for skill learning in sport
- explicit awareness
- attention
- motivation
- reward in adaptation
importance of coaches
- directs the trials and errors
- reduce space that needs to be explored
- assists in choosing the optimal long-term strategy
neurocognitive skill development;
increased perceptual skill is associated with…?
- map expansion
- alteration in temporal response of neurons
- improved attention at subconscious level
automaticity
- not necessarily indicative of high proficiency
- false ceiling
motivation may improve motor performance through
- general arousing or energizing effect
- goal specific component
results of practice
- gain in underlying capability for skilled performance
- then improved capability leads to improved performance
performance does not equal
learning
motor learning
set of processes associated with practice or experience leading to relatively permanent gains in the capability for skilled performance
learning results from
practice and experience
observing learning
- not direct; must observe products of learning
- CNS alterations occur during practice
- products of learning can be measured via changes in skill
changes in learning occur in
- decision-making processes
- movement control processes
learning requires permanent changes
-temporary effects can change performance
measuring motor learning
performance curves= average performance of large # of people practicing a task
- large changes occur early in practice and level out later on
- dont indicate progress in permanent capability
- all subjects do not improve at the same rate
transfer designs
- used to determine whether effects are permanent or temporary
- retention test is given
- paddles on hands for swimming to keep fingers together, then take paddles off and see if fingers stay together
break down skills not as effective for
rapid skills (tennis serve)
specific transfer
- limited range of variations
- bball free throw
generalized transfer
- learning goal is relatively similar to the training task
ex) jump shot in bball - develop general capabilities for a wide variety of skills
visualization
- mental imagery
- imagining action without physical practice
- shown to improve performance
- not as good as physical practice but better than none at all
how visualization works
- imagining allows physiological creation of neural patterns in your brain, as if you performed the action
- trains the mind to create neural patterns
mental imagery impacts
- motor control
- attention
- perception
- planning memory
