31/10/2017

MJM. NDT Lucerne October 2017 1

Motor Control and Motor learning:

Why does sensation matter?

…...and a few reflections on Bobath/NDT

Dr Margaret Mayston AM

m.mayston@ucl.ac.uk

Talk outline:

• An example

• Sensory functioning and intervention

• Definitions

• A working model for motor

control/learning/intervention

• Relevance of sensory functioning for

learning/relearning

• Relevance of sensory functioning for Bobath/NDT

• Reflection on the current challenges for

Bobath/NDT

• What is the future for Bobath/NDT?

2

Variety of everyday functioning:

3

An example……………….

4

2 signatures- similar but

different: why??

PRIMARY OBJECTIVE OF

INTERVENTION?

OPTIMAL

PARTICIPATION

5

Why does sensation matter ?

How do Bobath/NDT therapists contribute to the goal of optimal

participation?

Motor control

Motor control: ability to regulate or

direct mechanisms essential to

movement. It includes an

understanding of how the CNS can

organize many different muscles,

joints; how sensory information is

used from the environment and the

body to select and control movement;

it is about perception of ourselves and

the environment in which we live,

move and influence motor behaviour.

Complex!

Definitions

6

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MJM. NDT Lucerne October 2017 2

Motor learning

……. when considering the range and

complexity of the processes that are

involved in motor learning, even the mere

mortals among us exhibit abilities that are

impressive. We exercise these abilities

when taking up new activities — whether it

is snowboarding or ballroom dancing — but

also engage in substantial motor learning on

a daily basis as we adapt to changes in our

environment, manipulate new objects and

refine existing skills……….. (Wolpert et al

2011)

Motor learning/adaptation: generally refers to the neuronal changes

that occur to allow an individual to accomplish a new motor task, to

perform a task better, faster or more accurately than before usually

refers to motor adaptation. Adaptation can be advantageous or

considered to be maladaptive. Important to consider: “acquisition,

retention and transfer of skills”

7

Definitions

Easy for the typical person but not for the one with CNS impairments of functioning 8

“Sensorimotor learning involves learning new mappings

between motor and sensory variables. Such

transformations are termed internal models.”

“Learning is strongly determined by neural representation of

motor memory that influences how we assign credit during

learning and how learning generalizes to novel situations”

“Skilled performance requires the effective and efficient

gathering and processing of sensory information relevant

to an action”

Wolpert et al 2011.

Definitions

Motor learning & relearning

Two basic types of motor activity: simplistic

Ballistic Guided by feedback

Forward model

Open-loop

Problems with accuracy but fast

Useful for well known tasks

Updated through learning

e.g. tennis serve

Feedback model

Closed-loop

Accurate but problems of

delays;

Useful for novel tasks

Enables learning

e.g. balance on a beam 9

A working model…..

10

Motor control/learning: Information processing model

Idea

Need

Desire

Motivation

Plan

Extrinsic

Intrinsic

Posture and

task activity

Internal

feedback

Execution

Command to

muscles

Sensory

feedback

Appraisal

During the task

After the task

Adjust

feedforward

Feedforward

Feedback

Modified from Rothwell,

1994

“…one can only control what one senses….” McCloskey &

Prochazka, 1994

“Movements occur on a continuum of automatic to voluntary”

Hughlings Jackson, 1884

Movement science model

Simple every day task………

11

The International Classification of Functioning,

Disability and Health (ICF) 2001

Health condition (CP)

Activity

Participation

Body structure

and function

Personal

Factors

Environmental

Factors

Contextual Factors

Clinical model

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MJM. NDT Lucerne October 2017 3

1. Neuromuscular system

impairments:

• Tone

• Balance

• Coordination

2. Musculoskeletal system:

• Contractures

• Muscle weakness

3. Somatosensory and

perceptual, including

special senses

4. Cognitive

5. Cardiovascular/ respiratory

6. Gastrointestinal system

Participation Activity Body structure & Function

Activity

limitation

What is it the

child/person

cannot do or

does not do

efficiently?

Participation

restriction

Barriers to

societal

integration

Environmental factors Personal factors 13

Clinical model

Why does sensation matter?

• Enables performance of well timed, effective

actions: guidance via sensory feedback

• Basis of motor learning- creation of long term

motor memories: motor plans/internal model

built up by sensory feedback during task

performance

• Enables motor re-learning: sensory feedback

and forward systems- but the re-learnt task will

probably be performed differently

• Enables automatic performance of well known

tasks: interaction between sensory feedback

and feedforward (motor plans)

• Enables multi-tasking- much of what we do is

‘automatic’

• Enables carry-over effect of interventions

ESSENTIAL FOR MOTOR CONTROL,

MOTOR LEARNING & RE-LEARNING 14

A working model…..

15

Different types of sensory systems

Somatosensory:

touch, pressure, vibration

position sense (proprioception)

pain

temperature

Special senses:

vision

hearing

balance (vestibular)

taste

smell

Sensory perception: Sensory processing

16

Sensory pathways:

2 main systems, plus

spinocerebellar

afferent projection

17

Basic aspects of the control of movement

Motor : postural and task related activity

Sensory : the CNS finds the ‘right’ sensation

Cognitive : motivation, judgement, planning, problem solving

Perceptual : spatial, visual, figure-ground

Biomechanical : complementary aspect of neural and biomechanical

aspects of motor control

18

Other sensory

signals

Limbic system

Control of Movement:

• distributed system

• integrated function

Musculoskeletal system

A working model…..

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MJM. NDT Lucerne October 2017 4

Requirements for skilled performance

“Skilled performance requires the effective

and efficient gathering and processing of

sensory information relevant to an action”.

Franklin & Wolpert, 2011

19

A working model…..

20

How are movements organised to achieve behavioural goals?

• The CNS predicts (hypothesizes) what is needed to achieve the goal,

makes a plan and sends out a motor/postural command (feedforward):

i.e. movements made without online use of sensory feedback and

require an internal model; forward model/ anticipatory control

• This command activates motoneurones (usually via interneurones) in

the spinal cord which innervate the muscles required to execute the

task; muscles are also proprioceptors as well as force generators

• Even the simplest task requires activation of groups of muscles and generates sensory signals: Accurate control of movements requires a continuous flow of sensory information to correct errors

• The resultant movement generates sensory feedback (reactive control) which is used to correct any errors in the predicted plan or to counteract unexpected perturbations both at the level of the spinal cord and in supraspinal areas e.g. cerebellum, cortex (short and long latency reflexes and corrections to the plan). Online feedback

• The predicted plan for future performance (i.e. feedforward command)

of the task is updated if needed. Offline use of feedback

• There is continuum of control from feedback to feedforward for

optimal motor control

21

CNS plan

Task: Describe the

diagram with

words

..constant flow of sensory information………. 22

Sensory information for control of movement is processed at all

levels of the CNS

Jenner & Stephens, 1982

Touch

Proprioception

Temperature

Pain

23

Sensory control of grasp and lift

Johansson & Westling, 1991

in Johansson and Flanagan

2009

See also Koh et al 2015 24

Feedback and feedforward

(Reactive and anticipatory control)

Feedback: every movement generates sensory feedback

which is processed at all levels of the CNS. Relatively slow

(50 - 100ms): for regulation and adaptation

Feedforward: postural and motor commands are

generated by the CNS in advance of activity occurring and

without needing sensory input. Fast: for initiation and/ or

anticipatory activity.

Feedforward = preparation Feedforward = carry-over

Feedforward = learning

A working model…..

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MJM. NDT Lucerne October 2017 5

15o 30o

Parameters studied:

Angular displacement

EMG activity

Time taken to complete task: whole or part

Angular velocity

Intra-limb joint relationships

Motor control of UL: Biomechanics of UL functioning

25

EMG Data to show Muscle Onset Latency (S) Relative to the

Movement Onset in trial 'MMLTCUP06'

0 1 2 3 4 5 6

Time (S)

Fle

xorr

s E

xten

sors

B

icep

s P

ecs

Flexors

Extensors

Biceps

Pecs

Movement Onset

(1.82 S)

Sensory function and age- development and ageing

Reliance on sensory

feedback due to CNS

developmental process

and lack of experience

causes necessary

slowness of action and

over activity of muscle

groups

Reduction in efficiency

of sensory functioning

due to CNS regressive

processes causes

compensatory

slowness of action and

over activity of muscle

groups

Increasing age

Loss of motor units – mid 50s

26

Infant/child Adult

See Shaffer et al 2007

See Eliasson et al 1992

27

Changes in feedback and feedforward systems during

development

(Eliasson et al, 1992; Forssberg et al, 1995)

Sensory function and age- development and ageing

28

Changes in feedback and feedforward during development and

for children with CP (Eliasson et al, 1992)

29

Localisation of sensory field: development

Healthy, 7weeks

Healthy, 3y

Bilateral spastic CP. 3y

Leonard et al, 1995; see also Andrews &

Fitzgerald 1994 for sensory functioning in

the very preterm infant. See Kolb & Teskey

2012 for typical developmental changes 30

Somatosensory function and aging

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31

Mattay et al 2006; Ward 2006

Cortical function and aging: neural

Activation of other cortical areas for production of

hand movements

Widespread activation across the network in older people Biomechanical changes associated with ageing

Faulkner et al 2007. See

also Lee et al 2007

Younger (40yrs)

-10.00

0.00

10.00

20.00

30.00

40.00

50.00

1.0 2.0 3.0 4.0 5.0

time (s)

An

gu

lar

mo

tio

n (

de

g)

elb

w rist

shd

Time to complete task

y = 0.017x + 2.2255

R2 = 0.3646

0

2

4

6

8

10

0 20 40 60 80 100

age

tim

e (

s)

p= 0.01

32 Mayston et al, 2009

Fitts Law and Fitts/Posner (Keele, 1968): phases

of learning

33

COGNITIVE

AUTONOMOUS

ASSOCIATIVE

WHAT TO DO?

WHAT TO HOW

MINIMAL ATTENTION

Children’s vs adult learning?

Trial/error practice.

Movements

awkward and

clumsy

Movements

smooth,

fluent

Fact finding,

explanation,

demonstration

Relevance of sensory functioning for learning/relearning

Speed-accuracy trade-off………

Speed of learning is task dependent: simple vs complex e.g.

simple finger sequence vs piano playing (Dayan & Cohen 2011 ).

Neural activity changes during learning (Karni et al 1995;Wittenberg 2003

34

NB: an apparently simple task can become a complex ask for a

person with sensorimotor impairment.

35

Possible consequences of sensory dysfunction for person with

neurological impairment

Altered sensory intake : intensity,

localisation

Altered spinal processing

Reduced ascending input: eg.

conduction delays

Impairment of cortical processing

Altered sensitivity of spinal

motoneurones or reduced number

Altered motor output

Altered sensory feedback: “we

learn as we do and do only as

well as we have learned”

Reduced potential for

feedforward: “the movement

goes wrong before it starts”

Delayed motor responses

Slow task performance

Longer task learning time- more

practice needed

Mass synergies

Cannot multi-task

Relevance of sensory functioning for motor control

Evidence for sensory impairment in people with CNS lesions

36

Children:

• Auld et al (2012): tactile

dysfunction in children with

unilateral CP.

• Wingert et al (2010): less area of

sensory cortical activation shown

on brain mapping

• Damiano et al 2013: reduced

proprioception at hip resulted in

less stability and slower gait

• Kuczynski et al (2017 a & b):

impaired kinaesthesia in children

following perinatal stroke.

• Pavao et al (2015): postural

instability with impaired sensory

function

Adults:

Tyson et al (2008): tactile and

proprioceptive function post-stroke

and their relationship to function.

Goble et al (2008): ageing results in

‘impairments’ of sensation which

affect function and postural control

Butler et al (2008) Muscle weakness

impairs the proprioceptive control of

human standing

Sullivan & Hedman (2015) Review of

incidence of sensory impairments

following stroke. “The association

between the extent of sensory

dysfunction, the recovery of

somatosensation, and lesion site is

also unclear.

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MJM. NDT Lucerne October 2017 7

Are sensory impairments primary or secondary?

37

e.g. Hoon et al 2009 e.g. Forssberg 1999

Implications for potential for modification………..

Ways to enhance learning for typical and those with CNS

dysfunction (based on Muratori et al 2013)

Practice: varied, challenging (but not impossible), has

to happen in everyday life

Hands on/hands off?

Environment/context: meaningful

Knowledge of results: successful or not?

Reinforcement: how?

Error based or errorless? i.e. perfect (‘normal’) or the

best you can do, i.e. optimal?

Speed/accuracy trade-off:

Whole task or part practice?

Random order/blocked practice

Mental rehearsal; action observation

Sleep………

( & Adjuncts e.g. TMS)

38

Relevance of sensory functioning for learning/relearning

Implications of sensory impairments????

Components of therapy:

Therapy

components

HANDS-ON

THERAPY

RECREATION

Fitness/ sport

ASSISTED

PRACTICE: hands-

on robotics,

TTWPBWS etc

24 hour postural

management

ADJUNCTS:

Botox, orthotics,

mirror box etc

mental rehearsal

ACTIVE GOAL

PRACTICE

39

PARENT/CARER/

SELF COACHING/

INSTRUCTION

PARENT

COACHING

ASSISTED

PRACTICE

HANDS-ON

ACTIVE GOALPRACTICE

Video observation: components of therapy in those short

video clips/photos?

Produce an inventory of intervention to evaluate the therapies….

Starting with Bobath/ NDT, but also to evaluate the clinical

reasoning process

Ingredients of therapy: what makes up Bobath/NDT

40

Hands on-hands off: stretching?

Sensory stimulation: sensory processing?

Weight bearing

Play therapy incl. bimanual training?

Engagement

Setup environment: contextual therapy?

Train parents: parent training?

Education of parents: coaching of parents?

Repetition for learning

(? = Novak categories)

41

Effect of deafferentation

• Mott & Sherington, 1895: Dorsal root section led to

loss of limb activity. Conclusion - sensory feedback

is necessary for generation of purposeful

movement.

• Knapp, Taub, Berman, 1963: Bilateral vs hemi-

deafferentation (NB Munk 1909)

• Taub 1976: post-operative disuse overcome by

reinforcement procedures, although movements

clumsy. Afferent feedback necessary to perfect the

final detail. Provided a basis for CIMT.

• Rothwell et al 1982: “deafferented” man - large

repertoire of learned manual motor tasks executed

with speed and accuracy, no adaptation to new

tasks; performance of everyday tasks, especially for

fine manipulation difficult; excessive effort and

muscular activity. Important for learning new skills

Changes in understanding of sensory functioning:

42

• Basic objective of Bobath has not changed: : “lead them

[people with CP] towards the greatest degree of

independence possible… using a total management

programme.” Bobath & Bobath 1980

• The essence of Bobath/NDT is in the observation, analysis

and interpretation of a person's skills and challenges and

clinical decision making of what is possible for that person

to achieve.

• The hands-on/facilitation is only a small part of the

approach: Bobath, 1965: “……… unless you stimulate or

activate your patient in the way in which new activities are

possible, you have done nothing at all. So the handling

techniques as such are only the very first step in

treatment, though they are very important.” (italics mjm).

•

Changes in understanding of Bobath/NDT?

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43

2017 = Evidenced approach to Clinical Practice

EBP

Child and family

or person/carer

perspective

Therapists’

expertise

Evidence from

systematic research

and consideration of

current knowledge,

frameworks,

guidelines…..

In lieu of evidence……………. sound theoretical basis?

Continually review of current practice and theory through regular review

of literature.

44

What theory /knowledge can be

useful:

• Typical development

• Muscle physiology and

biomechanics

• Motor control/learning theory

• Neuroplasticity

Challenges for Bobath/NDT

1. Neuromuscular system

impairments:

• Tone

• Balance

• Coordination

2. Musculoskeletal system:

• Contractures

• Muscle weakness

3. Somatosensory and

perceptual, including

special senses

4. Cognitive

5. Cardiovascular/ respiratory

6. Gastrointestinal system

Participation Activity Body structure & Function

Activity

limitation

What is it the

child/person

cannot do or

does not do

efficiently?

Participation

restriction

Barriers to

societal

integration

Environmental factors Personal factors 45

Embed practice in current frameworks/clinical guidelines

The ICF framework and interventions: Fig 20.5 Mayston 2014

BoNTA; Train

balance reactions,

Muscle strengthening

and stretching; joint

alignment correction

CIMT; Task training;

Treadmill training;

ADL training

1. Neuromuscular

system

• Tone

• Balance

• Motor patterns

2. Musculoskeletal

system

• Muscle strength

• Range of motion

3. Somatosensory &

perceptual

4. Cognitive

5. Respiratory.

Cardiovascular

6. Gastrointestinal etc

e.g. walking

between

classrooms;

attend social and

sporting

clubs/activities;

occupation

Body structure &

function

Activity/Limitations Participation /

restrictions

Intervention system: Bobath/NDT

Educational based Intervention system:

Conductive education

Environmental factors Personal factors

Bobath/NDT is a system of intervention

• Multi- transdisciplinary: CP therapists/therapists

• Utilizes adjuncts- is not a ‘complete package’

• Family/child/person participation essential

• Handling is not the treatment:

• Why is the most important question

• Greatest strength is clinical reasoning

47

Challenges for Bobath/NDT in general (Mayston 2016)

• Bobath and NDT are not the same

• Some focus too much on ‘hands-on’ element

• Bobath/NDT is a ‘system’ of intervention

• Bobath/NDT for some can encompass many

types of intervention

• Bobath/NDT approach to adults seems to be

different from that for children

• No universally agreed definition

• Longevity and international utilization have

produced diversity of approach

• No universally defined ingredients of the

approach.

• What does the name ‘Bobath/NDT represent?

How can it be rigorously researched?

48

A need to provide evidence for efficacy…………

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International consensus on Bobath/NDT is lacking: no universally

agreed definition, theoretical basis or ingredients for universal

clinical practice.

49

“Another difficulty for

any review of

NDT/Bobath is that it is

not practiced and

taught uniformly

throughout the world,

thus studies of NDT/

Bobath intervention will

also differ and cannot

be viewed collectively”.

Mayston &

Rosenbloom, 2014

Challenges for Bobath/NDT in general (Mayston 2016) Current challenges for Bobath/NDT therapists:

• International, intra-country variability: no universal agreement

• Misunderstood and mis-represented

• Bobath/NDT is a ‘system’ of therapy

• Shares elements with other approaches

• What is unique for Bobath/NDT?

• What are the ingredients? How can the ingredients be

investigated?

• Embedded within ICF?

• Utilizes functional classifications: GMFCS, MACS, CFCS,

EDACS (paediatrics)

• Without experimental evidence- how to deliver evidence

informed practice (Rosenbaum 2012 – CP research is in its

infancy)

• What is the purpose of research? Is it to find out if one

intervention works better than another e.g. Bobath/NDTorCE,

etc,

• Or is it rather to find what works best for whom and at what

stage – is it possible? (Mayston 2012/14; Damiano 2014)

50

Considerations for Bobath/NDT practitioners…….

• Demonstrate that Bobath/NDT is a relevant, rational intervention with a

theoretical substrate based on the current scientific literature.

• Bobath/NDT is a clinically based approach which utilizes current theory

rather than the intervention being theory based- identify intervention

pathways.

• Review terminology and explanations for the Concept and its components.

• Demonstrate that Bobath/NDT is embedded within the ICF and current ideas

of client/family centred intervention.

• Have the humility to accept that Bobath/NDT is not a stand alone

intervention but utilizes other types of intervention to optimize outcomes.

• Not aiming to show that Bobath/NDT is better than other approaches but that

it has a positive effect and might be more effective in some cases.

• Emphasize that Bobath/NDT is primarily a clinical reasoning approach to the

management of the person with neurologically based activity limitations and

participation restrictions. Does the name matter?

• Accept that Bobath/NDT practitioners have a responsibility to measure

outcomes by systematic use of outcome measures and regular audit.

• Link with established researchers to investigate what works best for whom

and at what stage. 51

But, realistically what is the future?

Bobath = high heritage value

low value as a universal therapy approach

52

Bobath/NDT

???????

Health condition (CP)

Activity

Participation

Body structure

and function

Personal

Factors Environmental

Factors

Contextual Factors

Detailed knowledge

of body structure

and function: Neuromuscular, sensory,

cognitive, respiratory etc

Impairments

Activity limitations

Participation

restrictions

Capacity

Performance

Capability

Objective tests:

assess systems

functioning,

outcome measures etc

Clinical reasoning:

Why do I see the ICF as the essential

framework for my clinical practice?

• The focus is on the child and the family and what they

want to achieve: now and in the future

• Reminds me how important the family is in the child’s

life

• Emphasizes the importance of Family Centred care.

• Focus is on what the child can do

• Helps me to think about the importance of participation

in daily life

• Emphasizes the importance of contextual factors:

environment and personal factors

• Gives me a meaningful way to communicate with the

child, family and team of professionals

• It is not about aiming for ‘normal’ but optimality

• Perfect fit for my ’Bobath thinking’- might recognize

that this might not be true for all.

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55

Core

Bobath/NDT

Observation, analysis,

interpretation, experimentation,

forward looking

Families, school,

community

Play, handling to modify

tone/activity, repetition,

success, achievement

Practice, equipment, task

training, environments, home

activities

Observation, analysis,

interpretation, experimentation,

outcome measurement

Child/family centred, team,

inter/transdisciplinary

Muscle

strengthening,

fitness

CIMT, treadmill,

adjuncts

Sensory integration,

neuropsych,

education

Recreation,

sport

Sensory, perceptual, cognitive

training, communication,

eating/drinking

Postural

management

Botulinum, orthoses,

surgery, equipment

Mayston, 2008a&b

ICF

ICF

ICF

ICF ICF

ICF RESEARCH

BASE KNOWLEDGE &

FRAMEWORKS PRACTICE

GUIDELINES

THERAPISTS’

EXPERTISE

ICF

FCS/PERSON CENTRED

SOUND

CLINICAL

REASONING

CLASSIFICATIONS

GROWTH

CURVES

(PAEDS)

Clinical practice framework (Mayston, 2017 in press)

57

Thank you for listening – questions?