Motor Control

Question 1

Upper Motor Neuron (UMN)

Answer 1

Carries motor messages from the primary motor cortex to either the CNS nuclei (located in brainstem) or to the interneurons in the ventral horn. UMN travel up too but do not actually enter the ventral horn. UMN are considered to be part of the CNS

Question 2

Lower Motor Neuron (LMN)

Answer 2

Carries motor messages from motor cell bodies in ventral horn to skeletal muscles in the periphery. LMN are considered to be part of the PNS. Includes central nerves, peripheral spinal nerves, conus medullaris, cauda equina, and ventral horn

Question 3

What can cause a motor problem?

Answer 3

1) Neurological problem
2) Musculoskeletal problem

Sometimes something can start as a neurological problem and become a musculoskeletal problem

Question 4

Motor Control

Answer 4

Ability to regulate and direct the mechanisms essential to movement. Motor control comes after acquiring control of movement (motor learning)

Question 5

What does a person use to regulate and direct movement?

Answer 5

Neurological systems collaborate to make motor control possible. If there is damage to one system then it will affect an individual’s movement

Cerebral cortex: motor, visual, auditory, cognition, intellect
Basal ganglia: coordination, tone, equilibrium
Cerebellum: coordinated movements
Brain stem: righting reactions

Question 6

Is motor control just about muscles and nerves?

Answer 6

No! Motor control results when the individual is able to complete a task in an environment

Movement = person, task, environment

Question 7

Components of Motor Control

Answer 7

Selective movements
Tone
Postural control and mechanisms
- balance
- reflexes: primitive, equilibrium, righting reactions
Coordination
- types
- involuntary movements

Question 8

Tone

Answer 8

Resistance of a muscle to passive elongation or stretching

Neurological insult can impact tone

Flaccid - feels different from someone who has normal tone. Feels heavy and moves like jello

Question 9

Characteristics of Normal Tone

Answer 9

1) Effective co-activation of axial and proximal joints
2) Ability to move against gravity and resistance
3) Can maintain position of limb passively placed and released
4) Balanced agonist and antagonist muscle tone
5) Ease of shifting from stability to mobility and vice-versa
6) Ability to use muscles in groups or separately
7) Resilience or slight resistance in response to passive movement

Question 10

Muscle Tone Continuum

Answer 10

High Tone/Rigidity > Spasticity > Normal Tone > Hypotonia > Low Tone/Flaccidity

Flexor spasticity in UE occurs first and extensor spasticity in LE returns first

Extensor tone is easier to break than flexor tone

Encourage voluntary movement, ROM, meds, splinting to normalize tone following an insult

Question 11

Flaccidity

Answer 11

Complete loss of muscle tone

People are usually flaccid the first 48 hours following a stroke, followed by increasing resistance to PROM

Question 12

Hypotonia

Answer 12

Reduction in muscle stiffness

Characterized by low tone, weak neck and trunk control, poor muscular co-contraction, limited stability

Question 13

Spasticity

Answer 13

Hypertonicity

Question 14

Rigidity

Answer 14

Hypertonicity with heightened resistance to passive movement

Question 15

Modified Ashworth Scale

Answer 15

6-point scale
Lower scores represent normal muscle tone and higher scores represent spasticity or increased resistance to passive movement

Question 16

Clonus

Answer 16

Uncontrolled oscillations in spastic muscle groups
Repetitive contractions in the antagonistic muscles in response to rapid stretch
Actively weight-bearing can stop it

Question 17

Cogwheel Rigidity

Answer 17

Jerky resistance

Question 18

Clasp Knife Syndrome

Answer 18

Severe rigidity - sustained stretch will relax muscle group and give way (like when you’re returning the blade on a pocket knife

Question 19

Postural Control

Answer 19

Ability to maintain a steady position in weight-bearing, antigravity posture. Ability to center self vertically

Not formally assessed by OTs

Question 20

What influences postural control?

Answer 20

1) Neuromuscular mechanisms (e.g. ROM, strength)
2) Musculoskeletal mechanisms (e.g. ROM, strength)
3) Sensory mechanisms (e.g. vision, vestibular, somatosensory)
4) Perceptual mechanisms (e.g. body image, laterality)
5) Cognitive mechanism (e.g. attention, judgement)

Question 21

Postural Tone

Answer 21

Ability to react to gravity

Question 22

Normal Postural Control Mechanisms

Answer 22

Autonomic movements: provide an appropriate level of stability and mobility
Automatic reactions develop early in life and allow for:
- Trunk control and mobility
- Head control
- Midline orientation
- Weigh-bearing and weigh shifting in all directions
- Dynamic balance
- Controlled voluntary limb movements
After illness or injury, the “automatic” nature of movement is lost

Question 23

Balance/Postural Stability

Answer 23

Controlling the center of mass (COM) in relation to the base of support (BOS)
Maintaining an appropriate relationship between body segments and between the body, the environment, and task-orientation
Types of Balance:
1) Static balance (can be challenged with trunk rotation)
2) Dynamic balance

Question 24

Reflexes/Reactions

Answer 24

Righting reactions
Equilibrium reactions
Protective reactions
Primitive reflexes

Question 25

Components of Postural Mechanism

Answer 25

Must be integrated to be normal Normal postural tone and control Integration of primitive reflexes and mass patterns Righting, equilibrium, and protective reactions Selective voluntary movement

Question 26

Coordination

Answer 26

Ability to produce accurate, controlled movement

Question 27

Coordination Problems

Answer 27

Synergy: abnormal or disordered motor control Co-activation: agonist and antagonist muscles both fire, preventing functional movement Problems with timing

Question 28

Features of Coordinated Movement

Answer 28

``` Precision Smoothness Appropriate force of muscle tension Rhythm Speed Minimum number of muscle groups recruited ```

Question 29

Precision

Answer 29

Accuracy of movement (ex: undershooting vs. overshooting)

Question 30

Smoothness

Answer 30

Quality of movement

Question 31

Appropriate Force and Muscle Tension

Answer 31

Force to pick up an egg vs force to pick up a cup

Question 32

Rhythm

Answer 32

How one transitions from one movement to another

Question 33

Speed

Answer 33

How quickly you complete a motion

Question 34

Minimum Number of Muscle Groups Used

Answer 34

Movement efficiency

Question 35

Incoordination

Answer 35

Extraneous, uneven, or inaccurate movements Caused by trauma to muscles or peripheral nerve disease CNS dysfunction: - Cerebellar - Posterior column dysfunction - Basal ganglia dysfunction - Frontal or postcentral cortex

Question 36

Cerebellar Incoordination

Answer 36

Ataxia/dyssynergia Adiadochokinesis - inability to perform rapid alternating movements Dysmetria - undershooting or overshooting of intended position with the hand, arm, leg, or eye. It is a type of ataxia Nystagmus - vision condition in which eyes make repetitive, uncontrolled movements Dysarthria - difficult or unclear articulation of speech

Question 37

Extra-Pyramidal Incoordination Disorders

Answer 37

``` Chorea Athetoid movements Dystonia Ballism Tremor ```

Question 38

Dystonia

Answer 38

Sustained muscle contractions that result in repetitive, abnormal postures. It can affect on muscle, a muscle group, or the entire body

Question 39

Ballism

Answer 39

Violent slinging of the limbs that may only affect one side of the body

Question 40

Chorea

Answer 40

Rapid complex movements that look purposeful but are really involuntary movement

Question 41

Athetoid Movements

Answer 41

Usually a rhythmic writhing of the head, tongue, toes, or fingers.

Question 42

What are secondary effect factors that may impair purposeful, coordinated movement

Answer 42

``` Contractures Pain Edema Subluxation Decreased endurance - both muscular and cardiovascular ```

Question 43

Motor Learning

Answer 43

The study of the acquisition and/or modification of movement A set of processes associated with practice and experience that leads to permanent change in behavior or capacity to respond

Question 44

What is the difference between motor control and motor learning?

Answer 44

Motor control studies movement already acquired. Motor learning studies how movement is acquired

Question 45

When does motor learning occur?

Answer 45

1) During normal motor development as the nervous system matures 2) Re-learning motor skills post injury or disease 3) During novel situations Motor learning requires practice and feedback Therapeutic intervention: instruction, feedback, opportunities for practice, and encouragement/feedback

Question 46

How is training different from learning?

Answer 46

Training: temporary change that occurs when the performer is provided with solutions to problems. Examples: therapist encourages pt to memorize specific set of exercises or when a teacher provides student with an answer to a question. Training results in short term performance capabilities Learning: relatively permanent change in capability to respond occurs as a result of practice or experience. Example: performer is encouraged to develop solutions when problems are encountered. Learning allows persons to transfer knowledge or adapt to a new situation

Question 47

What factors influence motor learning? Which are most potent?

Answer 47

1) Stages of learning 2) Type of task 3) Feedback - most potent 4) Practice - most potent

Question 48

Stages of Motor Learning

Answer 48

Cognitive (verbal) stage: - Info gathered about task demands (learn elements of task) - Movement is slow and has a lot of errors - Explanations and demonstrations are valuable Associate stage: - Distinguish between correct performance and error - Attention to finer details Autonomous stage: - Skill is automatic and does not require attention - Performance is stable

Question 49

Types of Tasks

Answer 49

1) Activity demands determine the kind of motor response 2) Tasks may be classified on continuums 3) Serial, discrete, and continuous tasks

Question 50

Feedback

Answer 50

Provides guidance, reference for correction, and motivation. Feedback can be given through sensory information - tactile feedback or demonstrate and verbally explain

Question 51

Concurrent Feedback

Answer 51

Offered continuously throughout movement

Question 52

Terminal Feedback

Answer 52

Offered at the end of movement

Question 53

Intrinsic Feedback

Answer 53

Feedback from individual's sensory systems as a result of movement

Question 54

Extrinsic Feedback

Answer 54

Feedback from the environment (e.g. therapist or device) - Knowledge of Results (KR): knowledge of what the movement produces (outcome) in terms of achieving a goal or result. Correcting errors during movement. - Knowledge of Performance (KP): knowledge about the movement pattern or process used during task performance (e.g. biofeedback, verbal comments, or mirror)

Question 55

What evidence is there about the different types of feedback?

Answer 55

- Nothing has been published on concurrent vs terminal - Excessive concurrent feedback can be distracting to the learner - Frequent, accurate, immediate KR promotes improved performance during acquisition phase but poorer performance during retention and transfer stages of learning - Immediate KR helps prevent patient frustration - KR provided within a certain "bandwidth" leads to better generalization of learning - Feedback on performance should focus on external environmental factors and not on internal performance

Question 56

What is practice?

Answer 56

Effort to become proficient Practice should be active and accurate. Motor skill increases directly in relation to the amount of practice. Effect varies depending on the age, dx, amt/type of practice and task specificity

Question 57

Types of Practice

Answer 57

1) Physical | 2) Mental (i.e. motor imagery)

Question 58

Types of Practice Conditions

Answer 58

1) Massed: practice time is greater than the amount of time between trials 2) Distributed: rest time between trials equals or is greater than the time in trial 3) Constant: performance of task in same way (may improve performance but can be fatiguing and less effective) 4) Variable: perform task in different ways by varying characteristics of the task. This improves ability to generalize to various situations 5) Blocked: practicing each task in a block before progressing to a new task. This is better for cognitive impairment 6) Random: practicing a series of tasks in random order 7) Part practice: practicing a subset of task component 8) Whole practice: practicing the entire task Massed and distributed are related to endurance

Question 59

Evidence on Practice Conditions

Answer 59

- Physical practice is the best type but mental practice can be an effective way to enhance learning when physical practice is not possible - Blocked practice increases the speed of improvement - Random practice improves learning and recall - Practicing whole tasks is more effective than practicing parts of tasks - Variable practice increases generalizability in novel situations

Question 60

Skill Acquisition Feedback, Practice, Cueing

Answer 60

The initial learning of a new skill Feedback: frequent extrinsic, concurrent Practice: physical and mental, repetition, consistency Cueing: manual and verbal

Question 61

Retention and Transfer Feedback, Practice, Cueing

Answer 61

The long-term learning of a skill and the ability to generalize the skill to new contexts Feedback: less frequent, terminal Practice: promote entire patter, encourage problem solving, variable Cueing: allow for error and refinement, do not over cue

Question 62

What things should be considered in order for therapeutic motor learning to be successful?

Answer 62

- Therapeutic environment - Arousal and attention - Motivation and meaning - Instruction - Feedback - Practice Therapy should be individualized to the person and not the diagnosis

Question 63

What is the therapeutic intervention process?

Answer 63

1) Select tasks/activities to use during session 2) Provide instruction 3) Provide feedback about performance 4) Structure opportunities for practice 5) Provide encouragement

Question 64

What are OT treatment assumptions with neurological insult?

Answer 64

1) Healing is cephalo to caudal, proximal to distal and medial to lateral 2) Mobility should be established first, then proximal stability, next controlled mobility, and finally distal skilled movement 3) Mass patterns are replaced by selective voluntary movement 4) Gross motor to fine motor movement - Large mass movements come before discrete movements 5) Undifferentiated to specific movement 6) Asymmetry to symmetry and then symmetry to voluntary asymmetry 7) Midrange before end range 8) Vertical to horizontal in rotary movements 9) Movement should be relearned in purposeful patterns rather than specific actions 10) Motor control is gained via repetition