Motor Control - Finals

Gross Motor Skills

• Large muscle movements (e.g., walking, running, jumping).

  • First things we develop and should be developed once we are done with childhood

  • Ultimate goal with development is to gain individual and volitional movement

Fine Motor Skills

• Small, precise movements (e.g., writing, buttoning a shirt).

Closed Skills

• Performed in stable environments (e.g., swimming alone in a lane).

  • Self paced 

Open Skills

• Performed in unpredictable environments (e.g., basketball, driving).

  • Externally paced 

Discrete Skills

• Clear beginning and end (e.g., flipping a switch).

  • Short singular movement

Serial Skills

• Combination of discrete skills (e.g., gymnastics routine).

Continuous skills

• No clear beginning or end, ongoing movement (e.g., running).

Stimulus Identification

Information Processing

(Sensory input processing: vision, hearing, touch, kinesthesis).

Responce selection

Information Processing

(Deciding what to do based on stimulus).

Movement Programming

(Sending motor commands to execute movement).

Reaction Time

Time from stimulus to movement start.

Movement Time

•  Time from movement start to completion.

  • End of RT + completion of movement

Response Time

• RT + MT

Exteroception

• Info from the environment)
  
  

  • Vision: Defines space, detects movement.

  • Audition: Determines rhythm, distance, object identification.

  • Name: 

    1. extra - info provided

    2. Extero - info outside

Proprioception

• (Info from within the body)
  
  

  • Sense of position, movement, balance, and limb control.

Dorsal Stream

• Movement control, spatial awareness, visually guided actions.

  • Vision for action pathway 

• Arises in primary visual cortex but continues into parietal cortex

“where”

Ventral Stream

1.  Object recognition, conscious perception.

   • Vision for perception pathway

   • Arises in primary visual cortex but extends to temporal cortex

“what”

Reflex Theory

• Movement = response to stimulus
  
  

• Complex actions = chain of reflexes
  
  

• Limitations: Can’t explain voluntary or novel movements

Hierarchical Theory

• CNS has levels: higher centers control lower ones
  
  

• Top-down control: cortex → brainstem → spinal cord
  
  

• Limitations: Doesn’t consider reflexive behaviors from lower centers

Schema Theory

• Allows movement without sensory input
  
  

• Generalized Motor Program (GMP): Abstract representation adaptable to different situations
  
  

Parameters can change (speed, force, etc.)

Dynamic Systems Theory

• Movement = interaction of task, individual, and environment
  
  

• No central command needed
  
  

• Attractor States: Preferred movement patterns
  
  

• Control parameters can cause phase shifts

Ecological Theory

• Focus: Perception-action coupling
  
  

• Environment provides affordances (action possibilities)
  
  

• Perception drives movement

Degrees of Freedom

• Number of ways joints/muscles can move
  
  

• Challenge: CNS reduces DOF to control movement efficiently

Motor Synergies

• Muscles/limbs work together as a unit
  
  

• Reduces complexity of control
  
  

Feedforward

Anticipatory adjustments (open-loop control system)

Feedback

• Sensory correction during/after movement (closed loop control system)

Closed-loop control system

• AKA: Feedback or Reactive system
  
  

• Self-correcting via feedback
  
  

🔹 Key Elements:

1. Executive – makes decisions based on errors
   
   

2. Effector – carries out decisions (muscles, limbs)
   
   

3. Comparator – reference for correctness
   
   

Error Signal – feedback used to adjust movement

Closed-loop control system

• Used for continuous skills (e.g., walking, balancing)
  
  

• Allows real-time correction
  
  

🔹 Examples:

• Human body (homeostasis, balance)
  
  

• Thermostat (electric iron, AC)
  
  

• Water level controller
  
  

• Servo voltage stabilizer

Open-loop control system

• AKA: Feedforward or Predictive system
  
  

• No feedback during execution

Open-loop control system

🔹 Characteristics:

• Used for discrete skills (quick, one-time)

• Advance instructions determine action

• Not self-correcting during action

• Error correction happens after the movement

examples:

• Throwing a ball

• Swinging a bat

• Firing a gun

• Bread toaster (time-based)

• Electric hand drier
  

Individual differences

Definition: Stable and enduring differences between people in measurable characteristics or task performances.

These differences must be repeatable over time—not based on just one lucky or unlucky performance.

Individual differences

characteristics

1. Stable (not easily changed)
   
   

2. Enduring (last over time)
   
   

3. Repeatable (must show consistently across attempts)

Skills

• Proficiency at a particular task 

• Upgraded ability (sharpened and trained)

• Modified by practice (learned behavior)

Abilities

• “Basic level of a task”

• Part of the basic equipment people inherit to perform various real world tasks 

• Underlying factors (not yet completely refined; refinement stage)

• Can lead to development of a skill (in-training level)

General Motor Ability Hypothesis

• If you're good at one sport, you're probably good at others too.
  
  

• An all around athlete is one who posses a strong GMA for skilled motor performance 

Example: A student excels in football, basketball, and athletics due to strong general motor ability.

General Motor Ability Hypothesis

• Single, inherited motor ability is assumed

• Ability presumed underlies all related movements or motor tasks 

• Person with strong or high GMA could learn motor skills quicker and be got at a lot or all motor tasks

Edwin Fleishman

• Reaction time

• Response orientation 

• Speed of movement 

• Finger dexterity 

• Manual dexterity 

• Response integration 

• Physical proficiency abilities

reaction time

Responding quickly to a single stimulus

Start in a race

response orientation

Choosing between multiple movements/stimuli

Batting in baseball

speed of movement

Moving limbs quickly without a stimulus (goal: minimize movement time)

Swinging a bat, sprinting

finger dexterity

Handling small objects with fingers and hands

Playing piano

manual dexterity

Handling larger objects with hands/arms

Dribbling, juggling

response integration

Combining many sensory inputs to act

Cheer stunts, quarterback plays

physical proficiency

Basic physical fitness & strength traits

Strength, balance, stamina, etc.

physical proficiency

1. Dynamic strength 

2. Explosive strength 

3. Gross body coordination

4. Stamina (cardiovascular endurance)

5. Others (agility, flexibility, balance, and equilibrium)

^^ group of tests = superb physical fitness

practice

#1 factor in learning

Practice ≠ Repetition Only

• It’s not about mindless repeats.

• Real practice = active learning and adjusting every time.

• Repetition = repeating a movement again and again 

  • This concept brings to mind the idea that repetitive movements somehow “groove” or “stamp in” a memory (more repetitions = deeper groove)

Specificity of Practice

“You learn what you practice.”

• Skills improve in specific environments you train in.

  • Basis of the “home-field advantage”

Example: To play well in the rain, practice in the rain.

Sensory Feedback Matters

• Visual, auditory, and tactile feedback from practice helps build skill memory. (Proteau)
  
  

Removing these during actual performance hurts performance.

Principles of Practice

1. practice is not repetition only

2. specificity of practice

3. sensory feedback matters

benefits of practice

• effective performance

• perceptual skills

• attention

• error detection

effective performance

• Developing the capacity to perform some skill on future demand with proficiency and effectiveness

• Movements become a skill because you do things with less effort & less time

perceptual skills

• Efficient use of proprioception and exteroception to observe and analyze the environment and situation 

• You adapt: see patterns, hear, see, feel, and balance better

attention

• Reduced capacity demands 

• Reduced attention that is demanded by tasks that are well learned

error detection

Ability to analyze own errors and make corrections in the moment (self-sufficient & don’t need other’s check for improvement)

Fitt’s 3 stages (perceptual-motor learning)

1. cognitive

2. fixation (associative)

3. autonomous

cognitive

• (the first problem is overthinking)
  

  • You’re confused, thinking a lot, need coaching & guidance

  • Figuring out what to look at the environment 

  • Movements are rough and uncoordinated

  • Cannot determine one’s errors 

Fixation (associative)

(cognitive problems are solved)

• Errors are fewer, movements smoother

• Focus is shifted to organizing more effective movement patterns 

• Closed skills become routine (stereotypic); open skills become adaptable
  
  

Autonomous

(expert performance & high perceptual anticipation)

• Skill is automatic
  
  

• You can make higher-level decisions (strategy, emotion, multitasking) with less thinking (less cognitive)

• Muscle memory 

Bernstein’s 3 stages of learning

Stages of learning from a combined motor control and biomechanical perspective

Reduce degrees of freedom

• Too many joint/muscle options — you reduce what you move to gain control

  1. Fewer motion of body for conscious control 

  2. Attention is devoted to few degrees of freedom 

  3. Provides maximum control of significant aspects of action
     
     

release degrees of freedom

• Release DOF that are not necessary to achieve success in the action 

You start using more body parts efficiently (for power, speed, and faster & greater accumulation of forces)

exploit passive dynamics

• You master using momentum, gravity, and muscle elasticity (help of physics hehe)
  
  

Efficient & Effective = Skilled

Bernstein’s 3 stages of learning

• reduce degrees of freedom

• release degrees of freedom

• exploit passive dynamics