Kinesiology 406

Motor control, motor learning and skilled performance

Useful information

Associate Professor, Dr. John Buchanan

Web page: http://bucksplace.tamu.edu Syllabus handouts by section Articles etc.

Useful information - Grading Exams and quizzes

6 quizzes 3 major exams 1 comprehensive final

Questions: MC, short-answer, Fill-in-the-blank, Essay, true-false, labeling-drawing

graphs, Computations

Assignments: Lab exercise: required

Class project Experimental participation

3 experimental sessions and 1 write-up

Review paper An 8 page review of literature on a specific topic, based on 4 articles

Chapter 1 The Classification of Motor Skills

As a scientific discipline, the area of motor control …

Motor control: definition

As a scientific discipline, the area of motor learning …

Motor learning: definition

Degrees of freedom: the problem of motor control? (the outflow side) What can a muscle do?

How many muscles in the human body?

How many possible muscle activity patterns are there?

How many nerve cells in the brain?

Sensory-perceptual processes as part of the problem of motor control? (the inflow side)

What is the role of our sensory systems in controlling our actions and learning?

What does it mean to perceive something?

What does it mean to remember or recognize something?

Why is paying attention important for learning?

How can the problem be approached?

Physical mechanisms

Abstract processes

Theoretical (representing information)

Similarities and differences

Which of these two actions are the most similar and why?

11

Basic Terminology

Voluntary control

Movements (and kinematics)

An action (or motor skill)

12

Classifying actions based on muscles

Muscle size Fine actions

Gross actions

13

Classifying actions based on starting, stopping, and rhythm

General action type Continuous

Discrete

Serial (sequential)

14

Classifying actions within the environment

Action initiation and context stability Closed motor skills

Open motor skills

Chapter 2The Measurement of Human

Performance

16

Experiment: Participants

Populations

Samples

Selecting a sample

17

Experiment: manipulating, measuring, and baseline

Independent variable

Dependent variable

Control condition

Experimental condition

18

Dependent variables: performance outcome (goal-action) measures

Temporal measures Reaction time (RT):

Movement time (MT):

Spatial measures

19

Dependent variables: performance production (movement) measures

Kinematics

Electromyography

Brain signals

20

How do you record outcome and production measures?

Computers Keypads Joystick or mouse

How do you record kinematic production measures?

Computers and motion analysis system

Sampling the action over time

Viewing kinematic data

Stick figure representation of movements and actions

23

Plotting kinematic data: time series and angle-angle plot

extension

flexion

Flex Elbow extend

Fle

x

Wris

t

exte

nd

Wrist angle

Elbow angle

60 deg

24

Displacement and velocity

30 cm

0

Vel

(cm

/s)

Time (sec)

0 1.75.5

Vel. =

Speed. =

25

Displacement and EMGS

Targets

1 sec

De

gre

e

EM

G(m

V)

0

1 00

200

300S m a ll T arge ts

-20

-10

0

10

20 B ice ps

Deg

ree

EM

G(m

V)

0

100

200

300

-20

-10

0

10

20 T ricep s

near

far

How is muscle activity related to limb movement?

26

Analyzing performance and outcome measures: mean = (x)/n

Arithmetic mean: elbow-wrist flexion-extension task

(x)/n = (x)/n =

Why is the mean important?

elbow (flx-ext)5959606160615961

wrist (flx-ext)5758626364665461

27

Computing errors for outcome and performance measures

The task has a specific goal and the participant receives a score.

Constant error (CE)

Absolute error (AE)

Variable error (VE)

28

Constant error (CE): directional bias

Goal: elbow-wrist flexion-extension task – 60 degrees of rotation

ElbowDeg. Error1) 592) 593) 604) 615) 606) 617) 598) 61

WristDeg. Error1) 572) 583) 624) 635) 646) 667) 548) 61

start: CE = end: CE =Mean CE = Mean CE =

29

Absolute error (AE): accuracy

start: AE = end: AE =Mean AE = Mean AE =

Goal: elbow-wrist flexion-extension task – 60 degrees of rotation

ElbowDeg. Error1) 592) 593) 604) 615) 606) 617) 598) 61

WristDeg. Error1) 572) 583) 624) 635) 646) 667) 548) 61

30

Variable error (VE): consistency

Wrist angle dataMnCE score (Mn-sc) (Mn-sc)2 (Summed)/n sqrt 3.375

x/n = VE =

Goal: elbow-wrist flexion-extension task – 60 degrees of rotation

31

Analyzing performance and outcome measures: mean (x)/n

Arithmetic mean: simple reaction time (RT) scores

RT (sec.).500.450.525.475.370.600.510.490

RT (sec.).210.215.225.205.202.222.217.208

Constant error (CE): directional bias

Goal: learn to complete an action in a specific time, MT=1.5 secs

Start of practiceMT Error1) 1.2 sec2) 1.9 sec3) 1.3 sec4) 1.1 sec5) 1.1 sec

End of practiceMT Error1) 1.6 sec2) 1.7 sec3) 1.7 sec4) 1.6 sec5) 1.8 sec

start: ce = end: ce =Mean CE = Mean CE =

End of practiceMT Error1) 1.6 sec2) 1.7 sec3) 1.7 sec4) 1.6 sec5) 1.8 sec

Start of practiceMT Error1) 1.2 sec2) 1.9 sec3) 1.3 sec4) 1.1 sec5) 1.1 sec

Absolute error (AE): accuracy

start: ae = end: ae =Mean AE = Mean AE =

Goal: learn to complete a movement in a specific time, MT=1.5 secs

Variable error (VE): consistency

Start of Practice data CEMnCE score (Mn-sc) (Mn-sc)2 (Summed)/n sqrt

VE =

Goal: learn to complete a movement in specific time, MT=1.5 secs

Root mean square error (RMSE)tracking task

T1

T2

T3

T4

T5

T6

T7

T8

T9 T10

10

0

20

36

Root mean square error

10 targets1) 92) 203) 94) 185) 86) 167) 78) 149) 6.510) 6

10 scores1) 9.1 2) 223) 44) 205) 56) 187) 6.58) 199) 5.510) 5

RMSE1) 2) 3)4)5) 6) 7)8)9)10)

RMSE =

T1

T2

T3 S 1

S 2

S 3

37

Brain recordings and imaging

EEG

fMRI

PET

38

fMRI: functional MRI - BOLD

Blood oxygenation level dependent (BOLD)

deep

surface

39

Kandel, Schwartz, Jessel (1991). Principles of Neuroscience, Figure 22-5, pp .315

top - nose

Figure 2C

radioactive tracer – sugar (surface and deep structures)Level of tracer in neurons

Positron emission tomography:PET scan - rCBF

40

Kandel, Schwartz, Jesse (1991). Principles of Neuroscience, Figure 22-6, pp .316

PET scan and visual stimuli

Chapter 4Neuromotor Basis of Motor Control

42

Types and Functions of Neurons

Three types of functional neurons

Where does an action start and where does it end?

43lateral view

Cerebral hemispheres

Left right

dorsal view

eye

fa ce

lips

ja w

ton gueswa llow

brow

neck

thumbfingers

handwrist

elbowarm

shoulder trunk

hip

knee

toes

44

p harynxto ngue

jawgum steeth

lips

fa ce

no see ye

thu m bf ingers

h andforea rm

elb owarmh ead

n ecktrun kh iplegto es

Somatotopic maps: commands to muscles and body sensation to cortex

Penfield and Rasmussen (1950)

45

Electroencephalography (EEG): movement preparation

46

Motor cortex to muscles

Crossing over of control signals

Left-H.

Right-H.

Connectivity and surface area

47

Motor planning and sequencing areas

48

B.

A.

C.

Anatomy and function: MRI and PET

49

Continuous and discrete actions

Schaal et al. (2004). Right wrist flexion-extension motion 4 actions (Fig. 1A and 1B)

ext

flx

ext

flx

ext

flx

ext

flx

50

Continuous and discrete actions: brain activity patterns

Schaal et al. (2004). Figure 2C

Bilateral activity

Unilateral (contra-) activity

51

Subcortical structures

Basal ganglia – 4 components

Caudate

Basal Ganglia pathways

PutamenGlobus Pallidus

Substantia nigra

53spinal cord

Brain stem and cerebellum

54

Cerebellum and timing

Ivry et al., (2002). Spencer et al., (2003).

Discrete tapping

Continuous motion

55

Dorsal

Ventral

Spinal cord: sensory-motor information flow

56

Alpha (a) motor neuron

Input

Conduction

output

57

Muscle fibers and motor neurons

Alpha()-Gamma () co-activation

A) Alpha MN activates:

A B

B) Gamma MN co-activated:

59

Features of the motor unit

420,000:

252,000,000:

Average ratio

Force output

30-50%

Time (sec)

1

2

3

4

5

Force production: The size principle and motor unit activation

61

Spinal circuitry and Final common path

Reflexes

Interneurons

62

100Time in msecs

Muscletension

Patellartendonstruck

Knee Jerk

Muscleefferent

Muscle spindleafferent

0

Stretch reflex: mono-synaptic

Sensorycell

Motorneurons

extext

63

Inter-neurons and information divergence

Painfulstimuli

sensoryinput

Crossed-extensor reflex: divergence

Extensorsinhibited

Flexorsexcited

Extensorsexcited

Flexorsinhibited

+ excitation- inhibition

inter-neuron

Motorneurons

Sensory cell axon

extflx

65

+-

+

Descending Signal

Information feedback: inhibition

66

motor neuron

Final common path: information convergence

67

Hierarchy of the Motor System

Strategy (planning) PMC, SMA, basal ganglia

Tactics (setting parameter for execution) MC, cerebellum, basal ganglia

Execution Brain stem and spinal cord

Chapter 9Attention as a limited capacity

resource

69

Two main aspects of attention

Splitting attention

Focusing of attention

70

Information processing model

3 stage model of cognitive motor processes

CNS

71

Splitting attention

Dual task paradigm

SP RS RP

SP RS RP

72

Splitting attention: a simple motor task

Force output and attention (Leob, 1886)

The dual task

Variables

Finding

Splitting attention: Gait and Parkinson’s disease O’Shea et al. (2002)

Primary task

Secondary task

Splitting attention: Gait and Parkinson’s disease

Walking speed

Stride length

Controls PDs Controls PDs

Motor (coins)

Cognitive (count)

o Look at the standing task that was also done with this experiment.

75

Splitting attention: a clinical setting

Geurts and Mulder (1994) – relearning

What is an appropriate Dual task?

Variables

8 weeks of rehabilitation therapy

76

CoP (sway) and attentionC

oP V

eloc

ity

2 weeks 8 weeks

77

Cell phone and drivingWhy talking and driving don’t mix!

Reaction time

Red lights

Cell phone – bigger impact than!

Brain activity

78

Central-resource capacity: Flexible allocation (Kahneman 1973)

Rules of allocation

Cognitive effort

79

Multiple-resource theories (Wickens 1992)

80

Arousal, attention and performance

Levels of arousal low, optimal, high

arousal

Perf

orm

ance

lowpoor

high

best

81

Focusing Attention

Width

Direction

Switching

Automaticity – skill level

82

Neural basis of attention

Reticular activation system (red lines) Emerges from the reticular formation in brainstem

83

Visual selective attention

Visual selective attention

Shank and Haywood (1987)

Kato and Fukuda (2002)

85

85

Chapter 10

Memory components, forgetting, and strategies

86

Principles of human remembering and forgetting

What are the functional roles of memory?

How are memories encoded, stored, and recalled based on these functional roles?

Comparison of verbal and motor memory

87

Multiple memory model

Atkinson and Shiffrin (1968)

Baddeley (1986, 1995)

Working Memory Long-term memory

88

Working memory (WM) static characteristics

Duration

Capacity

Action example - Ille and Cadopi (1999)

89

Increasing WM capacity: subjective organization (chunking)

Starkes et al (1987)

Who remembers the most (produces the most) under a given condition?

Why do the experts remember more in the structured condition?

90

Long-term memory (LTM) characteristics

Functional LTM systems

Knowledge

Capacity and Duration

91

Neural aspects of LTM memory formation

H.M. (1950’s) suffered from epilepsy

Mirror Tracing

Mirror

Hand blocked from view

Mirror tracing

Retention tests

93

Remembering and forgetting

Encoding

Retrieval

Forgetting

94

sliding handle

Encoding: Categorization of actions

Magill and Lee (1987)

Free recall:

95

Encoding: verbal cues and actions

Shea (1977) - lever positioning task – without vision

3 verbal cues labels

3

12

2

111

10

Recall interval

96

Verbal cues as mnemonics for movements

5 sec 60 sec

AE

(d

eg

)

Retention interval (sec)

5

6

7

8

9

97

Proactive interference: WM

Location and distance

Step 1

Step 2

Step 3

Experimental group Control group

98

Retroactive interference: WM

Step 1

Step 2

Step 3

Experimental group Control group

99

Retroactive interference: motor task

Stelmach and Kelso (1970)

A

100

Interfering with motor consolidation

Muellbacher et al (2002) – TMS study

Task:

Goal

Issue:

101

TMS immediately after practice

Hypothesis:

Experimental group

Control group

3 Practice sessions P3P2

1.0

2.5

0.0

1.5

2.0

0.5

P1

1.0

2.5

0.0

1.5

2.0

0.5N

orm

aliz

ed A

ccel

erat

ion

Motor cortex

Occ. cortex

Pre-frontal

rTMS1 rTMS2

102

TMS long delay after practice

Hypothesis:

Experimental group

Control group

1 Practice session

rTMS

1.0

2.5

0.0

1.5

2.0

0.5Nor

mal

ized

Acc

eler

atio

n

1.0

2.5

0.0

1.5

2.0

0.5

P2P1

6-hr

res

t

103

Attention, memory, and learning

Foerde et al. (2006).

Dual task paradigm – shape sorting task

fMRI data

104

Neuro-anatomical regions and memory

No-distraction:

Secondary task

Multitasking

Material for Test #1Chapters 1, 2, 4, 9, and 10