4/4/2016
Childhood Apraxia of Speech: New
Directions for Diagnosis and Treatment
Iowa Conference on Communicative Disorders
2016
Carlin Hageman, Ph.D.
Professor Emeritus, Department of Communication Sciences and Disorders
University of Northern Iowa
ASHA: The definition
• Childhood apraxia of speech (CAS) is a neurological
childhood (pediatric) speech sound disorder in which the
precision and consistency of movements underlying speech
are impaired in the absence of neuromuscular deficits (e.g.,
abnormal reflexes, abnormal tone).
– CAS may occur as a result of known neurological impairment,
– in association with complex neurobehavioral disorders of known or
unknown origin,
– or as an idiopathic neurogenic speech sound disorder.
• The core impairment in planning and/or programming
spatiotemporal parameters of movement sequences results
in errors in speech sound production and prosody. (American
Speech-Language-Hearing Association. (2007). Childhood Apraxia of Speech [Technical
Report]. Available from www.asha.org/policy.)
Key Concept
• Speech consists of movements that give
rise to an acoustic signature that we
recognize as speech.
– Not places
– Not targets
• What does this mean for assessment if you
believe that CAS is a disorder of movement?
– What if: Weakness or muscle tone
– What if: No weakness or tone issues
Apraxia of speech
Childhood Apraxia of Speech
• a neurological childhood
(pediatric) speech sound
disorder in which the
precision and consistency
of movements underlying
speech are impaired in the
absence of neuromuscular
deficits (e.g., abnormal
reflexes, abnormal tone).
Acquired apraxia of speech
• Apraxia of speech (AOS) is a
"neurologic speech disorder
that reflects an impaired
capacity to plan or program
sensorimotor commands
necessary for directing
movements that result in
phonetically and
prosodically normal speech"
(Duffy, 2013, p. 4).
CAS Characteristics
• Sound production errors
– Especially across sequences of sounds
– What other kinds of speech productions are there?
• Movement disorder – not a phonological disorder
• Difficulty imitating articulatory configurations
– Especially transitions into and out of spatial targets for
phonetic strings
– Not a strength or muscle tone issue
• Difficulty with initial sounds
1
4/4/2016
Contextual variability in CAS
• Errors increase as complexity increases.
• Errors increase with sibilants, affricates and
blends.
• Errors increase with length.
• Better with repetition (forms basis of DTTC Rx)
• Error inconsistency
• THESE ARE NOT UNIQUE TO CAS
Yorkston, Buekleman, Strand & Hakel, 2010, page 410
Criteria from Davis et al. (1998)
• Speech characteristics:
– Limited consonant and vowel repertoire
– Frequent omission errors
• Predominant use of simple syllable shapes
– Increased errors on longer units
– Significant difficulty imitating words
• e.g., groping or unwillingness to attempt the task
– Presence of vowel errors
– Inconsistent articulation errors
– Altered suprasegmentals (e.g., rate, pitch, loudness)
Assessment Procedures
Criteria from Shriberg et al.
• Suprasegmental markers
– Inconsistent stress
• Lexical Stress Ratio
– Inconsistent timing (speech and pause)
• Coefficient of Variation Ratio
– Inconsistent oral-nasal contrasts
Determine Impairment
• Case history
• Oral mechanism examination
• Linguistic
• Motor speech examination
• Articulation/Phonological system
• Motor execution
– Neuromotor status
– Structure-function
– Phonological Disorder
• Sensorimotor planning
– Childhood apraxia
– Childhood dysarthria
2
4/4/2016
Case History
• Medical history
– Genetic syndrome
– Neurologic damage
• Developmental history
– Feeding problems
– Little vocal play or babbling
– Delayed onset of language
Assessment Tasks
• Selection of imitative utterances
– Words of increasing length
– Multisyllable words
– Phrase repetition
– Short to long sentences
Assessment Tasks
• Selection of imitative utterances
– Vowels in isolation
– CV and VC syllables
– CVC words
• Same beginning/ending consonant
• Different beginning/ending consonant
Assessment Tasks
• Analysis of speech production
– Error analysis focusing on anticipatory and
regressive assimilation, metathetic errors
– Identify any vowel errors
– Observation of speech motor programming (e.g.,
groping, dysfluencies, struggle)
– Variability in production
• Context effects
• Repetition effects
– Speech intelligibility measure
Assessment Tasks
• Other speech production tasks
– Assess resonance and prosody
• Intermittent hypernasality/hyponasality
• Inappropriate pitch or loudness patterns
• Inappropriate stress on multisyllabic words
– Assess fluency
• Volitional nonspeech movements
• PRINCIPLES OF MOTOR LEARNING
• “PROCESS OF ACQUIRING THE CAPABILITY
FOR PRODUCING SKILLED ACTIONS” (Schmidt,
1988, page 345).
3
4/4/2016
Qualities of a skilled movement
• Maximum certainty
• Minimum energy expenditure
Stages of Motor Learning
• Idea of movement
• Understand basic pattern/coordination
• Requires problem solving
– Cognitive
– verbal
• Minimum movement time
Motor Program Theory - Overview
Motor Program Theory - Overview
• Degrees of freedom
• Open-loop control
• Motor program
• Closed-loop control system
– Use of centrally determined, prestructured commands
sent to effector system and run off without feedback.
– Controls rapid and discrete movements.
– Number of components
– Number of ways each can perform
– Set of motor commands – defines essential details
of skilled action
– Central pattern generator
– Control system using feedback and error detection to
control movement.
– Controls slow, deliberate movements
– No more than 3 per second
Motor Programs
• How & When
– Programming includes the following:
•
•
•
•
•
Particular muscles involved in the action
Order in which the muscles are activated
Relative forces of the muscle contractions
Relative timing and sequencing of contractions
Duration of the respective contractions
Schmidt & Wrisberg, 2008
4
4/4/2016
Generalized Motor Programs
• Surface features – easily changeable
components of movement
• Parameter values
– Movement time
– Amplitude
– Also called parameters
• Easily changeable
Generalized Motor Programs
• Variations in movement time
• Variations in movement amplitude
• Variations in the limb or muscles used
Deep Structure
• Fundamental structure of an action
– Sequencing and relative timing (or rhythm) that
defines the movement pattern.
• Relative-time very important
– Difficult to change once learned
• Sets of ratios
Butterfly Study (Hageman and Carr, 2009)
Study of relative timing across syllables at different rates.
Normal rate:
Fast rate
Slow rate
• SCHEMAS
– INITIAL CONDITIONS
– PARAMETERS
– RECALL SCHEMA
– RECOGNITION SCHEMA
• Memory
– Explicit
– Implicit
FLY
--------
BU
TER
BU
TER
FLY
---
-
-----
BU
TER
FLY
------
------
------
------
---
• PRINCIPLES OF MOTOR LEARNING
– PRACTICE AND EXPERIENCE
– REPITITION AND FEEDBACK
– PRACTICE VERSUS LEARNING
– RETENTION VERSUS ACQUISITION
• ATTENTION AND MEMORY
5
4/4/2016
NEW CONCEPTS ABOUT PRACTICE
• LEARNING VS RETENTION PROCESSES
– LEARNING SHOULD BE MEASURED ON RETENTION TASKS.
– PERFORMANCE LEVELS DURING ACQUISITION ARE
FLAWED OR AMBIGUOUS
• ACQUISTION - SET OF PROCESSES OCCURRING DURING
PRACTICE
• RETENTION -SET OF PROCESSES THAT OCCUR AFTER PRACTICE
IS COMPLETED.
• GENERALIZATION - SET OF PROCESS LEADING TO
PEFORMANCE ON VARIATIONS OF THE SKILL
• RETENTION AND GENERALIZATION NOT SEPARATE FROM
LEARNING BUT ARE MEASURES OF IT.
Inverted U principle
– Process goals – emphasized over outcome goals
– Assure that learner goals are realistic
• Massed practice – type of practice schedule in which
the amount of rest between practice attempts or
between practice sessions is relatively shorter than
the amount of time spent practicing
• Distributed practice – a practice schedule in which
the amount of rest between practice attempts or
between practice sessions is relatively longer than
the amount of time spent practicing.
Average
Poor
Moderate
• Higher when learner is aware of evaluation.
• Early stages of learning – high arousal is
detrimental to learning
• What to do?
Practice
(Schmidt & Wrisberg, 2008)
Excellent
Low
Arousal
High
Arousal level
Goals
• Process goals: targets for performance
improvement that focus of the quality of
movement production
• Outcome goals: targets for performance
improvement that focus on the end result of
the activity.
6
4/4/2016
Internal focus vs external focus
• External focus -- better retention
– Example: Wulf et al., 1999
• Golf – focus on the pendulum movement of the club or
focus on the swinging motion of the arms and correct
grip.
• Learners retained the shot better with external focus
– Why – too much conscious control exerted over
movement which conflicts with open-loop control
• Led to jerky, hesitant movements
• External focus – allowed motor program to run
• What do we do as speech-language
pathologists?? Where do we focus our
learners? Why?
Practice
• When teaching a target skill
– Instructions should be brief and simple, emphasizing
no more than one or two points at a time
– Use concepts that learner is familiar with and that
remind learner of previous known experiences that
are transferable to the new skill
– Provide demonstrations conveying essential features
– Direct beginners to the key features of the
demonstration
Instructions
• For activities moving around in space,
instructions regard spatial targets are
particularly useful
• Spatial targets for speech?
• Can all instructions be given verbally?
• What about demonstration instructions?
– Modeling
– Observational learning
Practice
• Suggestions for instructional assistance (cont.)
– Set realistic performance goals
– Shorter practice sessions which are spread out
– Balance amount of practice and rest within a practice
period to fitness level of learner and energy
requirements of the movement.
Practice Implications
• In short short practice times, encourage many
repetitions.
– Challenge is to keep task from becoming boring or
repetitious in a negative sense (mechanical)
• For continuous tasks, especially containing an
element of “risk” , more rest is better.
• Energy demands
– Learners capacity for energy
– Task analysis
Learning
• Use of models and demonstrations can be too
much -- depends
• Observation learning enhanced when
imitation is delayed.
– Studied in sign language acquisitions studies
– Increases cognitive effort
– More independent learning
7
4/4/2016
NEW CONCEPTS ABOUT PRACTICE
• RANDOM VERSUS BLOCKED PRACTICE
– BLOCKED OFTEN CALLED DRILL (inaccurate)
• SHEA & MORGAN (1979) – MOTOR TASK
– STR0NG ADVANTAGE FOR RETENTION WITH RANDOM
PRACTICE CONDITIONS
– RANDOM PRACTICE LESS EFFECTIVE DURING ACQUISITION
Practice
• Part practice – practice of a complex skill in a more
simplified form; has three types
– 1. Fractionzation – two or more parts of a complex skill are
practiced separately.
– 2. Segmentation – one part of a target skill is practiced
until learned, then a second part is added to the first part
and then practiced together & so on. (also called
progressive part practice.
– 3. Simplification – the difficulty of some aspect of the
target skill is reduced (e.g., slow-motion practice)
Practice
• Error detection – demands sensitivity to wide range
of information produced by the movement.
– For golf?
– For speech?
• Develop sensitivity to patterns of movement that are
related to the performance outcomes!
• How do we direct learners attention to this?
• Definitely not while performing
• After learning to detect them, we can learn to fix
them.
NEW CONCEPTS ABOUT PRACTICE
• COMMON PRINCIPLES
– BEST RETENTION – ADDED DIFFICULTY
– RETRIEVAL PRACTICE ITSELF IS IMPORTANT
Practice
• Part practice – best in serial tasks where actions in
one part do not influence the actions in the next.
– Is this true for speech?
– At what point does this become true for speech?
• Schmidt & Young (1987) when rapid discrete actions
are broken into arbitrary parts, these parts become
so changed from the way they operate in the whole
task that practicing them in isolation contributes
little to whole-task performance.
Practice
• Types of mental rehearsal
– Mental practice – performers think through or about the
cognitive, symbolic, or procedural aspects of a motor skill
in the absence of overt movement.
– Mental imagery – individuals imagine themselves
performing a motor skill from either a first-person
perspective or a third-person perspective
– Verbal-cognitive stage – initial stage of learning, in which
verbal and cognitive processes dominate the learners
activity.
8
4/4/2016
NEW CONCEPTS ABOUT PRACTICE
• FEEDBACK
– GENERAL ASSUMPTIONS: THINGS THAT
•
•
•
•
INFORMATION MORE IMMEDIATE
MORE ACCURATE
MORE FREQUENT
MORE USEFUL
– CONDUCIVE TO LEARNING – IF MEASURED
DURING ACQUISITION
Types of feedback
• Intrinsic feedback
– sensory information that performer experiences producing
a movement
– exteroception --sources outside the body (e.g., see
changes in the environment)
– interoception --sources within the body (proprioception
• Extrinsic feedback
– sensory information provided by an outside source
– provided in addition to which the performer senses
– “augmented feedback
Feedback schedule
WHEN AND HOW MUCH
•
•
•
•
IMMEDIATE FEEDBACK
SUMMARIZED FEEDBACK
DETAILED VERSUS SIMPLE
BIOFEEDBACK
Feedback
• Feedback: What is it
• Feedback is sensory information that indicates
something about the actual state of person’s
movements (e.g., proprioceptive feedback
about the feel of the movement).
• Assumption: Performers compare this actual
feedback to the expected feedback of the
desired goal to determine the amount of
error.
Types of feedback
MOST IMPORTANT --Extrinsic feedback is under the
control of the instructor or therapist.
• Intrinsic feedback may be enough
• Depends --upon the nature of the task and the
capabilities of the learner
Schmidt & Wrisberg (2008)
• KNOWLEDGE OF RESULTS
– KR DELAY INTERVAL
– POST KR DELAY INTERVAL
• KNOWLEDGE OF PERFORMANCE
• FEEDBACK PRINCIPLES & ISSUES
• WHEN & HOW MUCH FEEDBACK
– IMMEDIATE FEEDBACK
– SUMMARIZED FEEDBACK
– DETAILED VERSUS SIMPLE
9
4/4/2016
• KNOWLEDGE OF RESULTS
• Knowledge of Results (KR)
– augmented (often verbal) information provided
after the action which indicates the degree to
which the performer attained the desired
movement with respect to the environmental
goal.
– KR that duplicates intrinsic feedback is of little use
or even detrimental to learning
• Often KR is not redundant and can be the only
source of feedback regarding the effect of the
movement on the environment
• •Essential when intrinsic feedback sources are
diminished or distorted
• –how would the learner correct errors
• •SO INFORMATION REGARDING ERRORS IS
ESSENTIAL
Knowledge of performance (KP)
• KNOWLEDGE OF PERFORMANCE –KP
– WHEN AND HOW MUCH
•
•
•
•
•
•
•
•
•
IMMEDIATE FEEDBACK
SUMMARIZED FEEDBACK
DETAILED VERSUS SIMPLE
BIOFEEDBACK
What about extrinsic feedback
Motivational
Instructional
Dependency-producing
Energizes, inspires (can the opposite occur?)
Reinforcement
– Positive
– Negative
– Punishment
• Usually augmented, information about the
pattern of the movement.
– Kinematic feedback
– Examples from sports
• Your back was not arched enough
• You didn’t follow through with your hand.
• You stepped too much tot he right.
– Examples from speech
• You fill in…..
– This is information about the quality of the movement
not about the effect on the environment
Information
• What about the information itself
– Program feedback --provides the learners with
error information about the fundamental pattern
of their movement (i.e., the GMP, the temporal
underpinnings)
– Parameter feedback --provides the learners with
error information about the parameter values
(e.g., amplitude, speed, force etc.)
10
4/4/2016
Information
• Much more difficult to change GMP issues
• •Information regarding GMP should be given early in
the learning process
• •More support needed for learner because progress
can be slow
• •Parameter information can be provided and
implemented faster but is given after the GMP is
relatively established.
• •What kinds of feedback are we providing?
• •What do we expect our learners to do with it?
• In general --summary feedback results in
– Slower acquisition
– Better retention
• In general --the more complex the movement,
fewer trials should be summarized.
• Bandwidth feedback good for decreasing
dependency --encourages learner to depend
upon intrinsic feedback
Treatment Methods Suggested for CAS
• Articulatory
– Integral stimulation
– DTTC
• Prosodic
– MIT
– Contrastive Stress
• Tactile/gestural
–
–
–
–
Touch-cue method
PROMPT
Adaptive cuing technique
Signed taught phoneme
• Source
– Rosenbek et al., 1973
– Strand & Stoeckle, 2006
– Sparks & Deck, 1994
– Wertz, 1983
–
–
–
–
Bashir et al., 1984
Hayden & Square, 1994
Klick, 1985
Sheldon & Garves, 1985
Information
• Kinds of information
– Descriptive feedback --describes the errors
– Prescriptive feedback --describes the errors and
suggests solution
– Attentional cueing --prescriptive feedback that
directs attention
– Prescriptive feedback and attentional cueing may
provide larger gains
• •Depends --upon the knowledge of the
therapist & need for the information
Treatment approaches
• Motor-programming approaches utilize motor-learning principles,
including the need for many repetitions of speech movements to help the
child acquire skills to accurately, consistently, and automatically make
sounds and sequences of sounds.
• Linguistic approaches focus on CAS as a language learning disorder; these
approaches teach children how to make speech sounds and the rules for
when speech sounds and sound sequences are used in a language.
• Combination approaches use both motor-programming and linguistic
approaches.
• Sensory cueing approaches involve the use of the child's senses (e.g.,
vision, touch), as well as gestures to cue (or self-cue) some aspect of the
targeted speech sound. Cueing is often used in conjunction with other
approaches, such as motor programming (Hall, 2000b).
• Rhythmic (prosodic) approaches, such as melodic intonation therapy
(Helfrich-Miller, 1984, 1994), use intonation patterns (melody, rhythm,
and stress) to improve functional speech production
Treatment Methods Suggested for CAS – Tactile/Gestural
Touch Cue Method
• Tactile cues to the face and neck
• Combined with simultaneous
auditory and visual cues in 3
stages of Rx
– Stage 1: series of nonsense syllable
drills to teach the cues, movement
sequencing and facilitate selfmonitoring
– Stage 2: moves these “learned”
movement sequences into
monsyllabic and polysyllabic words
(includes real and nonsense words)
• Emphasizes distinctive feature
contrasts
Adapted Cueing Technique (ACT)
• Uses gestural cues
• Hand motions used to illustrate
patterns of articulatory
movement and manner of
production.
• Simultaneous modeling while
moving the hand (e.g., showing
tongue trajectory and jaw
closure)
• Hand motions show air release
– Stage 3: produces multiword
utterances and spontaneous speech
(Bashir, Grahamjones, Bostwick, 1984)
11
4/4/2016
Treatment Approaches
• General Guidelines
– Intensive, individual treatment required
– Begin at the syllable or word level (sequences)
– Focus on sound sequences and functional core
vocabulary
– Frequent, short sessions to avoid fatigue
– One new speech production skill at a time
Treatment Approaches
• General Guidelines (cont.)
– Emphasize visual, tactile, kinesthetic properties
– Follow an appropriate treatment hierarchy
– Target vowels and consonants with maximal contrast
– Begin with or without phonation
– Use backward chaining to facilitate sequencing in words
– Include prosodic aspects such as inflection, stress, and rate
• Stress, intonation, and rhythm in rhymes and songs
• a new sound in well established syllable/word shape
• a new syllable/word shape with well established
sounds
Treatment Approaches
• General Guidelines (cont.)
– Limited number of stimuli, particularly for difficult goals
– Use carrier or functional phrases
• Controversial Suggestions
–
–
–
–
• Some authors encourage maximum number of
trials per session
– Is this a good thing?
– Depends
Drill nonspeech tongue and lip movements
Address oral sensory awareness
Use tactile method for shaping positions and sequences
Emphasize tactile/kinesthetic self-monitoring rather than
auditory self-monitoring
Treatment Approaches
• Compensatory Strategies
–
–
–
–
–
Treatment MLG issues
Teach increased use of pauses (e.g., shorter phrases)
Include schwa between consonants in clusters as needed
Slow speaking rate by prolonging vowels
Practice deliberate speech
Produce multisyllable words with equal stress
Facilitation Treatment Techniques Suggested for
CAS (Yorkson, et al., 2010)
•
•
•
•
•
•
Phonetic derivation
Phonetic placement
Tactile cuing
Rate variation
Stress variation
Intonation variation
12
4/4/2016
CAUTION
• DISTINGUISH BETWEEN PRACTICING AND
ACQUIRING!!!!!
MLG(Motor Learning Guided)
(Hageman 2014)
• Randomized practice
• Reduced feedback (33%)
• Two sets (20 utterances each) of stimuli
– based on high functionality by the participants and their
primary care-givers
– The stimuli ranged from single words to full sentences (in a
written form)
– one set of stimuli  treatment,
– second set of stimuli  generalization effect
Treatment Protocol
• Step 1 The clinician produces the utterance from a
written stimulus card in random order
– Patient attempts utterance without assistance
(No feedback)
– Patient produces utterance 3 times with 4-second pause
between each attempt
– After 3 attempts, clinician repeats utterance then provides
KR (Knowledge of Results)
• Step 1 continues for a block of 5 stimulus items
Treatment Protocol
• Step 3 Repeat steps 1-2 with another block of five stimulus
items
• Step 4. Following completion of all 20 stimulus items with
steps 1-2, all 20 are randomly elicited from written stimulus
cards.
– Patient attempts utterance without assistance
(No feedback)
– Patient produces utterance 3 times with 4-second pause between
each attempt
– After 3 attempts, clinician repeats utterance, waits 4 sec., and
provides KR
• Breaks were provided if necessary between sets
Treatment Protocol
• Step 2 The utterance is elicited from a written
stimulus card in random order
– Patient attempts utterance without assistance
(No feedback)
– Patient produces utterance 3 times with 4-second pause
between each attempt
– After 3 attempts, clinician repeats utterance, waits 4 sec.,
and provides KR
• Step 2 continues for a block of 5 stimulus items
Model Hierarchy for Motor Learning Approach- Clark 2004
(Adapted from Hageman, 2004)
• Have client randomly draw five words, phrases, and/or sentences to use
during steps 1-5.
• Step 1: Clinician produces utterance elicited from written stimulus cards and then
waits 3 seconds.
• Step 2: Client attempts utterance 2 times without feedback-waiting 3 seconds
between each production.
• Step 3: After two attempts, clinician repeats the same utterance, waits 3 seconds,
then has client judge the productions.
– Allows time to process feedback and adjust motor program to produce
correct production.
• Step 4: Client judges correct versus incorrect production by correctly placing plastic
chips in “happy/sad face” cups.
• Step 5: Clinician provides feedback (KR-verbal or nonverbal)
– Outcome: 100%
» Nonverbal, chip returned to child if judged correctly
– Prescriptive: 50%
» location of articulation placements given every other error
• Step 6: Post KR delay of 3 seconds.
• Repeat steps 1-6 with a new set of 6 randomly drawn stimulus cards,
continue until session ends.
• Between groups of random practice have client take a short break if
needed.
13
4/4/2016
MLG 11 Rating Scale
•
•
•
•
•
•
•
•
•
•
•
11 Accurate, immediate (may include distortion but maintains
immediate intelligibility)
10 Delayed (greater than two seconds)
9 Delay (includes silent or audible articulatory groping and/or
posturing)
8 Immediate, acceptable approximation, though not immediately
intelligible
7 Delayed (2+seconds) acceptable approximation, though not
immediately intelligible
6 Self-correction
5 Repeat, asks for repetition
4 Incomplete, similar characteristics but not the target
3 Error (clearly not the target)
2 Error plus a delay (2+ seconds)
1 Perseveration (produces previous response)
PROMPT
Building your own therapy plan
(Hayden & Square, 1994)
• Prompts for Restructuring Oral Muscular Phonetic
Targets
– Emphasis on tactile/kinesthetic cues to the face and neck to
facilitate speech production
– Provides tactile and proprioceptive input regarding the place
articulators, amount of jaw opening and manner of
articulation
• Placement of the fingers is quite specific to cue place and manner
• Provided serially to guide sequences of movement for syllables and
words
• Originally prompts were specific to each English phoneme (cuing jaw
height, lip position, tongue height and position, muscular tension, and
air flow.
– Uses meaningful utterances through hierarchical approach –
easy sounds to more complex.
– Emphasizes prespeech posturing for physiological suppoort
Let’s practice
• Miscellaneous thoughts
– ASHA Portal
• http://www.asha.org/Practice-Portal/ClinicalTopics/Childhood-Apraxia-of-Speech/
• Practice schedule
•
•
•
•
•
•
– Types of practice
Feedback
Attention and memory
Number of attempts
Timing
Scoring or measurement
Other issues
Thank you for your attention
!
– My email: carlin.hageman@uni.edu
14
4/4/2016
Feedback
Practice
Example Hierarchy
15