Management of Acquired Apraxia of Speech: Incorporating Concepts of Motor Learning
Foundations of Approach
 The object of (many) speech interventions is to
induce the speaker to produce speech in a
different way
 Enhancing our understanding how interventions
induce behavioral change will improve our ability
to select and administer interventions
Why Motor Learning?

Motor learning has been of interest to coaches,
PE teachers, music teachers

Principles guiding instruction in skilled
movement are continually discovered and
refined

Perhaps these principles will enhance the
training of skilled speech movements

consider how the principles apply generally

consider specific applications to speech
movements

considerations for impaired neuromuscular
systems
Defining Motor Learning
 Schmidt & Lee (1999)
Motor learning is a set of processes associated with
practice or experience leading to relatively
permanent changes in the capability for
movement
Motor learning is a set of processes
 May include processes such as
 Identification of relevant environmental stimuli
 Selection, retrieval, and programming of
responses
 Perception of intrinsic and extrinsic sensory
consequences
 Evaluation of movement outcomes
 Encoding of movement memories
 Not all processes are known
Learning produces an acquired capability for
movement (habit)
 Learning is not defined as the change in
behavior, but rather as the capability to behave
differently
 It is an internal state
 Learning (Competence) versus Performance
Learning produces relatively permanent changes in
the capability for performance
 Separate from factors that temporarily change
performance (e.g., motivation, warm-up)
 What is “permanent”?
Motor learning is implicit
 Explicit learning: is verbalizable, conscious
 Implicit learning


Can be reflected upon but actual learning is
subconscious
Best facilitated through experience
How is motor learning measured?
A typical experiment
 Measure performance on an identified task
 Institute a training program
 Measure performance periodically during the
training program
 Discontinue the training program
 Measure performance shortly after training is
discontinued
 Measure performance some time after
training is discontinued
 Measure performance on related, but
untrained tasks
Typical clinical practice?
 Measure performance on an identified task baseline
 Institute a training program - treatment
 Measure performance periodically during the
training program – probe data
 Discontinue the training program
 Measure performance shortly after training is
discontinued – immediate retention
 Measure performance some time after
training is discontinued – delayed retention
 Measure performance on related, but
untrained tasks – carry-over / transfer
Implications
 Practice/Rehearsal
 Performance during training is not a measure
of learning
 Factors that result in better performance
during rehearsal may not have the same
effect on permanent learning and/or
carryover
 Learning should be assessed in the target
context (i.e., “the game”)
The Learner
 What does the learner bring to the learning task?
 Ability
 Past experience
 Motivation
Ability
 Refers to underlying aptitude or talent
 Gross motor coordination, visual acuity,
physiologic soundness
 May be affected by accident, illness, genetic
predisposition
1
Influences the amount of practice needed as
well as appropriate goal-setting
 Fundamental abilities cannot be improved
 Drills targeting balance, vision, quickness, etc
tend to improve performance only on those
drills, but not on other tasks

In Contrast to Ability
 Capability
 Characteristics that are subject to change as
a result of practice/experience and that
represent an individual’s potential to excel in
the performance of a task
 Maturity
 Strength and/or endurance
 Skill
 The capability of performing with maximum
certainty, minimum energy, or minimum time
 Developed as a result of practice
Motivation
 Achievement motivation relates to perception of
success in achieving goals
 Learners involved in goal-setting tend to be more
motivated
Past Experience
 New tasks often share features/characteristics
with familiar tasks
 Movement elements
 Perceptual elements
 Conceptual elements
Movement Elements
 Some tasks share similar movement patterns
Perceptual Elements
 Some tasks involve processing of similar
perceptual elements
 Prediction of opponent’s movement
Conceptual Elements
 Some tasks involve similar strategies, guidelines,
rules, or concepts
 Maintaining balance while losing contact with
ground
But on the other hand…
 Specificity of Training
 Carry-over from related tasks is not as great
as might be expected
 The best practice is on the task itself
 The benefit of transfer of common elements is
most pronounced early in training
 Negative transfer (in normals) is virtually nonexistent
Refining movements
 Closed skills
 Performed in predictable or stable
environments
 Learners “fixate” or reduce variability in
movements
 Open skills
 Performed in unpredictable environments or
while in motion
 Learners diversify their actions in response to
environmental conditions
The Law of Practice
 “Improvements in performance are generally
large and rapid at first and then become
systematically smaller as practice continues”
(Schmidt & Lee, 1999)
 Practice continues to be of benefit even when
performance during rehearsal seems to have
plateaued (overlearning)
Principles of Motor Learning
 Setting the stage for motor learning
 Skill presentation techniques
 Forms of rehearsal (practice)
 Task sequencing
 Providing feedback
Setting the Stage for Motor Learning
 Familiarize the learner with the task
 Direct attention
 Manage arousal
 Balance practice and rest
Familiarize the Learner
 Describe the “training” process
 Let the learner know how you will structure
activities, provide feedback, and deliver
instruction
 Encourage the learner to provide input regarding
the effectiveness of feedback, instruction, etc.
Direct Attention
 Motor learning is a mental task that requires
attention for cognitive processing
 External: attend to environment
 Internal: attend to internal cues (kinesthetics)
 Narrow vs Wide range of focus
 The instructor should direct the learner to attend
to the appropriate cues during various parts of
the movement and or during different stages of
training
Application: Give examples relevant for speech.
When would you have the speaker to attend to each
type?
2
Manage Arousal
 Early in training, high levels of arousal (anxiety)
can detract from learning
 Emphasize process goals rather than
outcome goals
 Assure learner that goals are achievable
 Low arousal levels (as is common in neuro
patients) also detract from learning
Balance practice and rest
 Massed versus distributed practice
 Research suggests that shorter sessions that
are more spread out lead to better learning
 Encourage as many repetitions as possible
during short practice sessions
Application
 How do you determine how long each treatment
session will be?
 Evaluate your treatment schedule for appropriate
balance of treatment and rest?
 How many repetitions/trials do you target per
session? How could you increase this target?
Skill presentation techniques
 Instructions
 Demonstration/modeling
 Guidance procedures
Instructions
 Usually verbal
 May include information about
 How the skill is used
 Where and how to move
 What to attend to
 What to expect when performing the skill
A caution about verbal instructions
 The language system is a gas hog
 Attentional resources devoted to verbal
processing cannot be allocated to other
processes that may be more relevant for
movement
 Instructions should be brief, emphasizing one
or two major points
 This is particularly true for individuals with
neurologic injury
Demonstration/modeling
 Observational learning has been widely
documented, although the mechanism of
observational learning is debated
 Demonstration must display the essential
features of the skill
 Requires attention – direct learner to most
important features
 View/perspective influences effectiveness
Guidance Procedures
 Physically, verbally, or visually direct learners
through a task
 Purpose is to reduce errors or dispel fear
Does Guidance Aid Learning?
 Not so much…
 Guidance can modify the “feel” of the task
 Reduces decision-making processes
 Reduces or eliminates experience of error
 Cannot make corrections
 In essence, guided movements are completely
different tasks than independent movements
However…
 Guidance very early in training may be more
beneficial than extensive verbal instruction
 Guidance should be removed as soon as
possible to allow for maximum learning
Forms of Rehearsal
 Physical Rehearsal
 Mental Rehearsal
Physical Rehearsal
 Simulation
 Part Practice
 Slow Motion Practice
 Error Detection Practice
Simulation
 Simulation can be very helpful when
 Task is expensive or dangerous (flying)
 Availability of facilities is limited (putting
green)
 Additional “people” are needed (batting or
tennis practice)
 Simulation will be most effective when practice
conditions precisely match target conditions
(guided practice?)
Part Practice
 Three types
 Fractionization
 Parts of the skill are practiced separately
 Swimmer practicing leg kicks
 Segmentation (Progressive part)
 One part is practiced until mastered, then
another part is added and practiced along
with the first, etc.
 Tennis serve toss
 Tennis serve strike
Part Practice
 Simplification
 The difficulty of the task is reduced by
modifying some aspect of the task
 Practicing batting using a wiffle ball and
an oversized bat
 Playing tennis using the doubles lines
3
 “The real question is does part practice,
regardless of how it is structured, contribute to
the learning of the whole target skill?” (Schmidt &
Wrisberg, 2000)
 Will practicing the simplified task transfer to
the whole target skill?
 How much time (if any) should be spent on
part practice?
 Would the time be used more effectively
practicing the whole skill?
Effectiveness of Part Practice
 Part practice works best when the individual parts
do not influence the remainder of the task
 Passing the baton during a relay
 When the relationships among the parts are high,
part practice eliminates the need for making
adjustments between parts
Effectiveness of Part Practice
 When rapid, discrete movements (e.g., golf
swing) are fragmented, each part becomes so
changed that little transfer of learning to the
whole task is observed
Slow Motion Practice
 Two hypotheses:
 Specificity of training applies to movement
speed, thus one would not expect good
transfer of slow motion practice
 Generalized motor program theory posits that
as long as the relative timing of a movement
is maintained, only the parameters are
changed during slow motion practice
Reconciliation
 When “task speed” is reduced, various aspects of
the movement are not necessarily slowed
proportionately, and timing among movements is
not necessarily maintained
 Speech rate changes
 Slow motion practice will be effective only if
speed changes are not so great as to require a
different motor program
Application
 What is the relationship between slow motion
practice and reduced speech rate?
 Is slow motion practice applied in speech therapy
in any other way?
Error Detection Practice
 How are error detection skills developed?
Return to Schema Theory
 “we learn skills by learning rules about the
functioning of our bodies---forming relationships
between how our muscles are activated, what
they actually do, and how those actions feel”
(Schmidt & Lee, 1999, p 373)
Information incorporated into movement schemata
 Initial conditions
 Response specifications (Motor program and
parameters)
 Outcome
 Sensory consequences
Initial conditions
 Environmental conditions
 Status of articulators
 Surrounding movements
 Generally implicit
Response specifications
 The instructions for movement (what did the brain
tell the body to do?)
 Motor program and parameters
 Implicit
Outcome
 Was the movement successful?
 If the movement was not successful, the degree
and nature of inaccuracy
 Only information that is likely to be explicit
Sensory Consequences
 Tactile
 Kinesthetic
 Proprioceptive
 Generally implicit
Recall Schema
 Used to select movement parameters
 Develops from cognitive processing of
relationships among
 Initial conditions
 Movement parameters
 Movement outcome
Recognition Schema
 Used to evaluate success of movement
 Develops from cognitive processing of
relationships among
 Initial conditions
 Movement outcome
 Sensory consequences
 Allows for error detection
Error detection practice
 The goal in error detection process is for the
learner to attend to the sensory consequences
related to performance outcomes
 Kinesthetic
 Tactile
 Auditory
Error detection = Self monitoring?
4
 Not exactly
Self monitoring (in SLP) tends to focus on
judgment of the outcome
 Was the sound produced correctly?
 Was normal resonance evident?
 Was speech intelligible?
 Error detection focuses on the sensory
experience related to successful versus
unsuccessful movement attempts
Cautions
 Learners should not attend to feedback during
the movement (other sensory information may
more important at that point)
 Focus on the bulls eye instead of arm tension
 Focus on speech sound rather than throat
sensation
 Error detection must be followed by error
correction, which may require assistance

Mental Rehearsal
 Mental practice
 Performers think through or about the
cognitive, symbolic, or procedural aspects of
a skill
 May be most effective alternated with physical
practice
 Mental imagery
 Imagining performance of the skill, from first
or third person perspective
 May be most effective when learner is quite
familiar with the skill
Does it work?
 Physical rehearsal is superior to mental rehearsal
 Mental rehearsal is superior to no rehearsal
Task Sequencing
 Practicing different tasks
 Practicing different variations of the same task
Practicing different tasks
 A
 B
 C
 D
Sequencing different tasks
 Blocked practice
 Same task is repeatedly rehearsed
 Random practice
 A number of tasks are rehearsed in no
particular order, with minimal consecutive
repetitions of any one task
Effectiveness of blocked practice
 Blocked practice enhances performance because
learners are practicing in a stable and predictable
environment
 The response specifications can be maintained in
working memory
 Carry-over is limited because most target
contexts do not involve unchanging repetitions
Effectiveness of Random Practice
 Elaboration hypothesis
 Learners appreciate distinctiveness of
different tasks
 Forgetting hypothesis
 Movement plan has to be regenerated for
each rehearsal
 Retrieval practice
Implications

practicing under stable conditions leads to
inappropriately high sense of accomplishment

blocked practice may be beneficial very early in
practice, when skill is being acquired (verbal –
cognitive stage)

a random schedule should be instituted as
soon as the learners “acquire a rough
approximation” of the target

“For therapy patients, who almost always have
some knowledge of and experience with the
tasks they are practicing, blocked practice may
never be appropriate” (Schmidt and Wrisberg,
2000, pg 236)

during the motor stage, blocked practice
should be avoided – rotate tasks continuously

effects of random practice are greatest when
target skills are most different from each other

be sensitive to frustration since random
practice leads to lower rates of initial success
Application
 What would be examples of “different tasks” that
speakers with motor speech disorders would be
rehearsing?
 Describe an intervention session that
incorporates random practice
Task Sequencing
 Practicing different variations of the same task
 A1
 A2
 A3
 A4
Variations on the same task
 “Same tasks” are assumed to use a single GMP
but with different parameter assignments
 Throw
 Jump
 “t” ?
 Constant practice


Learner rehearses only one variation of given
class of movements
Stable parameter assignment
5
 Varied practice


Learner rehearses a number of variations of
the given class of movements
Variable parameter assignment
Classic Experiment
 A throwing task has targets of 20, 30, and 40
meter distances
 2 groups practice
 Constant practice: 75 trials at one distance
 Varied practice: 25 trials at each distance
Results
 Immediate retention
 Constant practice group outperforms varied
practice group
 Delayed retention
 Varied practice group performs as well as
constant practice group
 Transfer (25 or 35 m throw)
 Varied practice group outperforms constant
practice group
Why? Return to Schema Theory
Application
 How do the principles of random and varied
practice relate to typical clinical methods?
 Given that varied/random practice results in
poorer performance during rehearsal, how would
the use of this scheme influence your criteria for
progression?
Feedback
 Types of feedback
 Purposes of feedback
 Providing Feedback
Types of Feedback

Intrinsic

Sensory information that arises as a natural
consequence of an action

Kinesthetics

Proprioception

Extrinsic

Provided to the learner by some outside
source

In addition to intrinsic feedback

Under the control of instructor or therapist
 Varied practice allows for richer schema
development
 Richer schemas (resulting from varied practice)
enhances flexibility and/or adaptability of
movement production, ultimately resulting in
greater success in novel contexts
Application
 What are examples of different variations of the
same task that speakers with motor speech
disorders may rehearse?
 Describe an intervention session that
incorporates varied practice
Random/blocked versus varied/constant

random/blocked refers to the “order” of trials for
different tasks

enhances learning because of elaboration
and/or retrieval practice

constant/varied refers to the number of
variations of a single task that are practiced

enhances learning because of the
opportunity to enrich the movement schema
Combining random
and varied practice

Random practice of the different variations of
the same skill

A1, A4, A3, A1, A2, etc

Combining variations of the same task among
variations of different tasks (throwing, catching)

A1, B3, A4, B1, A2, B4
Extrinsic Feedback

Knowledge of results (KR)

Usually verbal information about the
success in achieving an environmental goal

KR that duplicates intrinsic feedback is of
little value and may be irritating for learners

KR is most important when learner cannot
observe outcome or when intrinsic
feedback sources are diminished or
distorted (neuro)

Essential for learning

Examples

Made the basket

Shot was 2 yards long

“t” was produced

Knowledge of Performance (KP)
Feedback regarding the quality of the
movement

Examples

Good follow-through

You didn’t step through the kick

Your tongue was too far back

Purposes of Feedback

Motivation

acts as a stimulant

must identify the type of feedback that is
motivating

Reinforcement
6
results in increased probability of the
reinforced behavior

intermittent reinforcement is generally more
effective than constant (fading)
Information

enhances the quality of the movement (as
opposed to the frequency)

provides information that allows learners to
correct errors
Dependency-production

can act like physical guidance

learner can become too dependent on
extrinsic feedback



Application
 Give examples of how clinicians use feedback to
 Motivate
 Reinforce
 Inform
 How might feedback provided by clinicians lead
to dependency?
Providing Feedback
 Should feedback be given?
 What kind?
 How much information should be provided?
 How precise?
 How often?
 When?
Should feedback be provided?
 Feedback is more effective when the learner
requests it
 In some cases, “discovery” of the person-taskenvironment may be more helpful than immediate
extrinsic feedback
Application
 Imagine the experience of a speaker who has
experienced a motor speech disorder for only a
few days
 What kinds of intrinsic and extrinsic feedback
have they experienced?
 How does this “discovery” influence their
speech or their participation in treatment
 Would this be different for someone with
chronic AOS?
 Does “discovery” have any value during
intervention?
What information should be included?

feedback should address features under the
learner’s control
Program Feedback

Information about the fundamental pattern of
movement

Include motivation since this aspect of learning
may be slow

Most important early in task acquisition
Parameter Feedback

Information about parameters (amplitude,
speed, force)

More appropriate once basic movement
pattern is acquired
Visual feedback

Types

videotape of movement (mirror?)

biofeedback regarding other aspects of
movement (visipitch, emg)

split-screen

Caution: learners can only attend to small
amount of information at a time, instructor
should initially point out specific cues
Descriptive vs Prescriptive

Descriptive - describes the movement or the
outcome

Prescriptive

provides information about how to improve
the movement

generally more effective
Application
 Give examples of descriptive feedback that might
be provided to speakers
 Give examples of prescriptive feedback that
might be provided to speakers
 Can you identify any situations where one of
these types would be more appropriate than the
other?
How much information should be provided?

GMP: identify the one feature that is most
fundamental for task improvement

Parameter: may be able to combine features
(speed and force)
Reducing information overload

Summary feedback

given after a series of attempts/trials

includes information about each attempt

slows acquisition, enhances learning

Average feedback

feedback after a series of attempts

focuses on average performance - “the gist”

Both summary and average feedback allow the
learner to attend to intrinsic feedback to judge
movement accuracy
Application
 Describe a treatment scenario where feedback
was provided
 In summary
7

In average
 Do you see any particular value to these forms of
feedback for speakers with motor speech
disorders?
How precise should feedback be?

In general, feedback does not have to be very
specific

Direction of errors (too far right vs 2 feet to
the right)

Magnitude (too loud or 15 db too loud)

Precision becomes more important as the level
of skill increases
Bandwidth Feedback
 Feedback only when performance strays outside
of preset range
 Decreases feedback frequency (fading) and
allows for self-evaluation
How often should feedback be provided?

Reduced feedback frequency (50 -60% rather
than 80 – 100%)

Slows acquisition

Improves learning

Fading allows for reduction in relative feedback
frequency

Learners are forced to attend to intrinsic
feedback, self-evaluate, and self-correct
Application
 How frequently do you tend to give feedback?
 How would you go about reducing frequency of
feedback during intervention?
 Consider the strategies identified here
 Consider the kinds of tasks/skills typical of a
treatment session
When should feedback be provided?
 When feedback is provided, it should occur within
a time frame such that it is clear to which
movement the feedback pertains
 A short delay allows the learner time to process
intrinsic feedback for schema development
 That delay should remain empty
 Movement
 Verbal processing
How feedback is processed
 Immediately following movement, subject uses
recognition schema (initial conditions, movement
parameters, and sensory consequences) to
evaluate and/or predict accuracy
 Following KR, the subject incorporates movement
outcome, initial conditions, and movement
parameters into recall schema for future
movements
Application
 Consider how “verbal” speech treatment sessions
can be
 How could practice be modified so that
movement-related processing was maximized
while language-processing was minimized
 How would the presence of concomitant
aphasia influence the impact of verbal
processing
Support for Motor Learning
Speech/Oral Movements
Principles
in
Adams, S., & Page, A. (2000). Effects of selected
practice and feedback variables on speech motor
learning. Journal of Medical Speech-Language
Pathology, 8, 215-220.

40 normal adults speaking “buy Bobby a puppy”
at a slow rate

4 groups
 Constant practice /blocked practice/100%
feedback
 Constant practice /blocked practice / 20%
feedback
 Varied practice / blocked practice / 100%
feedback
 Varied practice / random practice / 100%
feedback

Effects of reduced feedback: Similar
performance at the end of rehearsal, superior
performance after 2 days

Effects of random practice: Similar performance
at the end of rehearsal, superior performance
after 2 days

Effects of varied practice: Similar performance
at the end of rehearsal, superior performance
after 2 days
Clark, H. M. & Robin, D. A. (1998). Generalized
motor programme and parameterization in Apraxia
of speech and Conduction aphasia. Aphasiology,
12, p. 699-713.
 Subjects completed a nonspeech task involving a
single movement pattern executed at different
speeds
 2 subjects with AOS evidenced impaired GMP
 2 subjects evidenced impaired parameterizaiton
S. Austermann, S. Robin, D., Ballard, K., Maas, E,
Schmidt, R. (2004). Low versus high frequency
feedback in apraxia of speech. Paper presented at
the Conference on Motor Speech, Albuquerque,
March 18 – 21.
 4 patients with AOS
 Alternating treatments design, 100% versus 60%
feedback
8
 Reduced feedback enhanced learning measures,
high frequency did not enhance acquisition


Knock, T. R., Ballard, K. J., Robin, D. A.,
Schmidt, R. A. (2000). Influence of order of
stimulus presentation on speech motor learning:
A principled approach to treatment for apraxia of
speech. Aphasiology, 14, 653 – 668.
 2 subjects with severe AOS
 Random practice facilitated retention, blocked
practice did not
Maas, E., Barlow, J., Robin, D., & Shapiro, L.
(2002). Treatment of sound errors in aphasia and
apraxia of speech: Effects of phonological
complexity. Aphasiology, 16, 609-622.
 2 subjects with AOS and aphasia
 Generalization from more complex forms to
simple forms for one subject
 No generalization from simple to complex
forms for either patient
Additional Reviews Related to AOS
 Ballard, K. J. (2001). Principles of motor learning
and treatment for AOS. Neurophysiology and
Neurogenic Speech Disorders, 11 (4), 13 – 18.
 Ballard, K. J. (2001). Response generalization in
apraxia of speech treatments: taking another
look. Journal of Communication Disorders, 34, 3
– 20.
 McNeil, M. R., Robin, D. A., & Schmidt, R. A.
(1997). Apraxia of speech: Definition,
differentiation, and treatment. In M. R. McNeil
(Ed.) Clinical management of sensorimotor
speech disorders (pp. 311 – 344). New York:
Thieme.
The Big Picture
 Defining Motor Learning
 Learning movement patterns is a cognitive
process
 Learners must attend to relevant stimuli,
outcomes, and sensory consequences
Measuring Motor Learning
 Performance during rehearsal/practice/treatment
does not reflect learning (retention/transfer)
 To assess learning/progress
 Identify assessment conditions that most
closely match the target context
Motor Control Strategies
 Speakers with AOS are attempting access
previously learned and/or develop new motor
programs and to parameterize these programs
appropriately
Speakers as Learners
 Most speakers with AOS previously produced
speech at an autonomous skill level
 They bring with them an understanding of the
process
 Underlying deficits in ability will influence the
speed and extent of skill development
Laws of Practice
 Acquiring and refining a skill requires a great deal
of practice
 The more movement trials the better
 Overlearning may be occurring even when
performance changes are not apparent
Skill rehearsal
 Many training factors that enhance learning result
in slower acquisition
 Random practice
 Varied practice
 Reduced feedback
 Treatments that speed progress are not
necessarily best in the long run (speed of
recovery should not be our goal)
 It isn’t necessary to structure practice so that
success rates are high, nor is it necessary to set
high success rates as criteria for progression
 To best serve our patients and our profession, we
need to diligently report progress/treatment
success based on outcomes obtained outside of
rehearsal
Specificity of training
 All evidence suggests that motor learning is
highly specific
 Part-practice does not tend to generalize to skill
in the entire task
 Practice of more complex skills may improve
skill on simpler tasks
Instructions and Feedback
 Excessive verbal processing will direct attentional
resources away from motor control processing
 Reducing feedback allows the learner to attend to
sensory consequences (more similar to the target
context)
And finally…
 These learning principles are applicable not only
to treatment of motor speech, but any treatment
addressing the motor system
 Articulation
 Fluency
 Voice and resonance
9