Childhood Apraxia of Speech PDF

Childhood Apraxia of Speech Mohammed Alqahtani Email: [email protected] Praxis - Definition ► "The generation of volitional (voluntary) movement patterns for the performance of a particular action, especially the ability to select, plan, organize...

Childhood Apraxia of Speech Mohammed Alqahtani Email: [email protected] Praxis - Definition ► "The generation of volitional (voluntary) movement patterns for the performance of a particular action, especially the ability to select, plan, organize, and initiate the motor Pattern which is the foundation of praxis" (Ayres 1985). Spatial-Temporal Coordination ► Critical to fluent, adult-rate speech-language production ► Dominates the development of speech-motor control over the first six years of life. ► Gradual increase in overall execution speed of motor programs over the ages 3-11 years. ► Segment durations are conditioned or adapted according to the linguistic content of the utterance (Netsell 1981) Motor sequencing ► Ordering the individual gestures that make up the whole motor plan and coordinating them with each other. ► Includes: ► Determining the order of the elements ► Figuring out how to get from one to the other (Ayres, 1985): transitions Apraxia: ► "A disorder in carrying out or learning complex movements that cannot be accounted for by elementary disturbances of strength, coordination, sensation, comprehension, or attention" (Strub & Black 1981). Apraxia ► Thus, apraxia or dyspraxia is a disorder of: 1. Volitional movement 2. Spatial-temporal coordination 3. Motor sequencing 4. Carrying out or learning complex movements 5. Central sensorimotor processes 6. Accommodation to context Types of Apraxia ► A person may have one or more types of apraxia at the same time. ► Major three types of apraxia: 1. limb 2. oral 3. verbal ► Limb apraxia: limb apraxia is associated with volitional movements of the arms and legs. Types of Apraxia ► Oral apraxia: The client with oral apraxia may be unable to protrude the tongue or smack the lips volitionally. Oral apraxia is sometimes confused with the third type, verbal apraxia since they both involve oral facial muscles but they are not the same. ► Verbal apraxia: Verbal apraxia is a disorder of motor programming for the production of speech. The client with verbal apraxia has difficulty positioning and sequencing muscles involved in the volitional production of phonemes. The Terminology ► Developmental apraxia of speech (OR) ► Developmental verbal dyspraxia (OR) ► childhood apraxia of speech ► Childhood Apraxia of Speech (CAS) is the current preferred terminology to describe the disorder. CAS: Early signs & symptoms ► Limited or little babbling as an infant (void of many consonants). ► First words may not appear at all, pointing and “grunting” may be all that is heard. ► The child is able to open and close mouth, lick lips, protrude, retract and lateralize tongue while eating, but not when directed to do so. ► First word approximations occurring beyond the age of 18 months, without developing into understandable simple vocabulary words by age 2. CAS: Early signs & symptoms ► Oral scanning or groping may occur with attempts at speaking. ► Continuous grunting and pointing beyond age 2. ► Lack of a significant consonant repertoire: child may only use /b , m , p , t , d , h /. ► All phonemes (consonants and vowels) may be imitated well in isolation, but any attempts to combine phonemes are unsuccessful. CAS: Early signs & symptoms ► Words may be simplified by deleting consonants or vowels, and/or replacing difficult phonemes(consonants and vowels) with easier ones. ► Single words may be articulated well, but attempts at further sentence length become unintelligible. ► Receptive language (comprehension) appears to be better than attempts at expressive language (verbal output). ► One syllable or word is favored and used to convey all or many words beyond age 2. ► A word (may be a real word or a nonsensical utterance) is used to convey other words beyond age 2. CAS: Early signs & symptoms ► Verbal preservation: getting “stuck” on a previously uttered word, or bringing oral motor elements from a previous word into the next word uttered. ► The child has difficulty moving the tongue where they want it to go. ► “Pop-outs” or automatic words and phrases are spoken clearly, but they cannot be imitated when directed or may not be heard again. ► Other fine motor problems may be present. CAS: ► CAS is a “symptom complex” ► No one feature is adequate for diagnosis ► Symptoms can include motor, linguistic, neurological. ► Inconsistency is expected across children and within same child ► Symptoms change over time Key characteristics of CAS ► Speech and Language Pathologists need to keep in mind that children with other speech sound disorders share some characteristics from the list. ► Other characteristics may be more common and contribute more specifically to the differential diagnosis of CAS, distinguishing CAS from the other pediatric speech sound disorders. ► the list below may be useful for identification of children suspected to have CAS. Key characteristics of CAS ► Limited repertoire of vowels; less differentiation between vowel productions; and vowel errors, especially distortions ► Variability of errors ► Errors increase with length or complexity of utterances, such as in multi-syllabic or phonetically challenging words. ► Depending on level of severity, child may be able to produce accurately the target utterance in one context but is unable to produce the same target accurately in a different context. Key characteristics of CAS ► More difficulty with volitional, self-initiated utterances as compared to over-learned, automatic, or modelled utterances ► Impaired rate/accuracy on diadochokinetic tasks (AMR & SMR) ► At some point in time, groping or observable physical struggle for articulatory position may be observed ► May also demonstrate impaired volitional non speech movements (oral apraxia) Etiologies ► Genetics (FOXP2) ► Prenatal issues ► Differences in myelination process ► Neurological disorders ► Developmental delay ASSESSMENT OF AOS ► Standardized tests for Assessment of AOS: 1. Verbal Motor Production Assessment for Children (VMPAC) 2. The Apraxia Profile 3. STDAS–2: Screening Test for Developmental Apraxia of Speech – Second Edition 4. Kaufman Speech Praxis Test for Children (1995) Diagnostic battery ► Major components: History, Description of Neuromuscular Status, Structural-Functional Examination, Motor Speech Examination, Sound System Description, & intelligibility. A. History: ► Medical History, ► Developmental History (Feeding, vocal play, Imitation), ► Family history, ► Communication skills (gap Between RLA &ELA), ► Psycho-social skills, ► Gross & fine motor Skills Diagnostic battery B. Description of Neuromuscular Status – Involves consideration of the child’s ► overall physical/neuromuscular status as a means of developing hypotheses about the child’s speech motor system, not for diagnosis (a medical determination). ► Indicators of motor involvement (Miller & Groher, 1990) 1. clumsy gait 2. asymmetry in muscle mass 3. low tone – reduced elasticity leading to open mouth posture, droopy eyes and facial muscles 4. adventitious movements 5. differences in strength and coordination in movement patterns other than speech 6. medical reports of pathological reflexes (especially indicative of dysarthria) Diagnostic battery C. Structural-Functional Examination – Emphasis on 5 movement parameters: 1.range of motion, 2.speed, 3.strength, 4.ability to vary muscular tension, 5.coordination D. Motor Speech Examination: ► (1) Connected speech samples: (a) conversation, (b) picture description c) narrative ► (2) Diadochokinesis :AMR,SMR ► (3) Use of an utterance hierarchy using imitation: ► Vowels in isolation (e.g., /i, o, ai/) ► CV and VC (Using various vowels), (e.g., me, my, hi, up on) ► CVC (Using various vowels ) ► first and last sound the same (e.g., mom, pop, cake) ► first and last sound different (e.g., pad, cat.) D. Motor Speech Examination: ► Words of increasing length (e.g., come, compute, computer) ► Multisyllabic word repetition (e.g., refrigerator, alligator) ► Phrase repetition (e.g., I want, me too) ► Repetition of sentences of increasing length (e.g., I want more, I want more milk, I want more milk please) ► Kaufman (1995) also gave very similar hierarchy. Hierarchy can be produced with increasing support: ► direct imitation ► modeling with visual and auditory cues ► tactile and gestural cues ► phonetic placement cues E. Sound System Description ► (1) Independent analysis: phonetic repertoire, syllable and word shapes. ► (2) Relational analysis ► Developmental processes – Patterns seen in children with typical development and most types of sound system disorder; may be very persistent in children with CAS ► Non developmental processes – Patterns seen rarely or only in early development; Of particular interest for CAS – Use of favorite sound, initial consonant deletion, vowel errors. ► children with DAS are more likely to show degraded performance across trials. ► Measures useful for relational analyses of single word productions: 1. Assessment Link Between Phonology and Articulation-Revised, Hodson 2. Assessment of Phonological Patterns-3; 3. Bankson & Bernthal Test of Phonology, 4. Khan-Lewis Phonological Analysis 5. Analysis of vowel errors can be done using – HAPP-3 6. Hodson Assessment of Phonological Patterns (Third Edition) – (HAPP-3) E. Sound System Description ► (3) Consistency – Similarity of word production across repetition ► (a) Obtain 2 spontaneous and 2 imitated tokens of selected words of a standard articulation test, particularly multisyllabic words (Shriberg, Aram, & Kwiatkowski, 1997c): ► (b) Expectations: children without DAS will usually improve across trials and with the model children with DAS are more likely to show degraded performance across trials. (4) Prosody :– Suprasegmentals characteristics typical of children with CAS are ► - Excessive, equal or misplaced stress ► - Omission of weak syllables, especially initially and medially ► - Currently most practically observed in connected speech samples (5) Intelligibility: measure speech intelligibility using ratings scales. The Apraxia Profile ► Author(s): Lori A. Hickman, M.S., CCC-SLP ► Identify the presence of developmental verbal apraxia and document a child's progress over time ► Administration: 25 to 35 minutes ► Publication Date: 1997 ► Ages / Grades: 3 to 13 years ► Overview: Use to assist in the differential diagnosis of developmental verbal apraxia, identify the presence of oral apraxia, and reveal the most problematic oral-motor sequences and movements. ► Document a child's oral-motor sequencing deficits and establish the level of oral movements and sequences produced successfully. ► Obtain helpful information to share with parents, teachers, and other professionals. STDAS–2: Screening Test for Developmental Apraxia of Speech – Second Edition ► The STDAS­-2 identifies children aged from 4 through 12 who have both atypical speech ­language problems and associated oral performance. ► These two key factors render children suspect for developmental apraxia of speech. The STDAS-­2 has four subtests. 1. The first subtest, Expressive Language Discrepancy, is a required pre- screening task. For this subtest, the difference between expressive and receptive language age is calculated if receptive language age is higher than expressive language age. This discrepancy remains the best indicator for further testing of developmental apraxia of speech. 2. Prosody, 3. Verbal Sequencing, and 4. Articulation, Kaufman Speech Praxis Test for Children (1995) ► by Nancy R. Kaufman, M.A., CCC/SLP - Ages: 2;0-5;11 ► Testing Time: 5-15 minutes depending upon severity of disorder. ► Norm-referenced; provides standard scores and percentiles. ► The KSPT assists in the diagnosis and treatment of developmental apraxia (dyspraxia) of speech in preschool children. ► Description ► The KSPT identifies the level of breakdown in a child’s ability to speak in order to establish treatment and track improvement. ► Easy to administer and score, the test helps measure a child’s imitative responses to the clinician, locates where the child’s speech system is breaking down, and points to a systematic course of treatment. Kaufman Speech Praxis Test for Children (1995) ► Highlights of the KSPT: 1. Items organized from simple to complex motor-speech movements, using meaningful words whenever possible 2. Imitative, stimulus/response format that can be administered easily without pictorial stimulation 3. Norm-referenced and standardized items that provide a raw score, a standard score, and a percentile ranking for each part of the test 4. A diagnostic rating scale that assists in delineating severity levels on a continuum