Interactions between Language and Stuttering

1. Interactions betweenLanguage and Stuttering J. Scott Yaruss, Ph.D., CCC-SLPUniversity of Pittsburgh NU/SFA Workshopfor Fluency SpecialistsJuly, 1996

2. Purpose • To examine aspects of language development that may be involved in the onset, development, and maintenance of fluency disorders • To discuss the relationships between language development and the diagnosis and treatment of stuttering

3. Interactive Relationship Between Clinical Research and Clinical Practice

4. ? ? ? ? What causesStuttering?

5. Factors That May BeInvolved in Stuttering Genetic Environmental Linguistic Motoric Psychological

6. ? ? ? ? What does Language have to do with Stuttering?

7. Language factors and stuttering • Situational Factors • Certain linguistic factors affect the likelihood that stuttering will occur on a given word or utterance • Developmental Factors • Certain aspects of language development affect the likelihood that stuttering may develop in an individual

8. boy dog mother bicycle Word-BasedFactors • Length • Familiarity • Phonetic Stress • Initial Sound • Position in Utterance • Meaning / Propositionality • Phonetic / Phonological Complexity (?)

9. The boy ran to his mother with his dog. Utterance-Based Factors • Length • GrammaticalComplexity • Pragmatic Intent • Meaning / Propositionality • Speaking Rate (?)

10. ? ? ? ? What do these situational language factors have to do with stuttering treatment?

11. What we already know about language and stuttering helps us plan evaluation and treatment • Determining appropriate level for activities (hierarchies of treatment) • Identifying speaking contexts or situations that facilitate speech fluency or exacerbate stuttering

12. ? ? ? ? How does language development affect stuttering?

13. Language SystemsApproach • Pragmatics: meaning of utterances • Semantics: meaning of words • Syntax: structure of utterances • Morphology: structure of words • Phonology: sounds of words

14. Language ModelApproach • Identify steps involved in language processing and production • Identify factors that might lead to disruptions in formulating language • Develop ways to treat these disruptions in language processing to improve speech

15. Basic Steps inLanguage Formulation • Figuring out what you want to say • Basic message • Pragmatic intent • Figuring out how you want to say it • Grammatical structure • Specific words • Sounds in the words • Prosody

16. CONCEPTUALIZER discourse model, situation knowledge, message encyclopedia generation etc. monitoring parsed speech preverbal message FORMULATOR SPEECH- COMPREHENSION SYSTEM grammatical encoding LEXICON lemmas surface structure forms phonological encoding phonetic plan (internal speech) phonetic string ARTICULATOR AUDITION overt speech Levelt’s (1989) “Blueprint for the Speaker”

17. Recent Models of Stuttering and Language • Recent theoretical models emphasize language processing skills • Covert Repair Hypothesis(Postma & Kolk, 1993) • Temporal Dyssynchrony(Perkins, Kent, & Curlee, 1991) • Sentence Plan Alignment(Karniol, 1995)

18. The Covert Repair Hypothesis (CRH) • Attempts to explain speech disfluencies produced by speakers who do and do not stutter in context of general language model • Theoretical Background • Levelt’s (1989) Blueprint for the speaker • Dell’s (1986, 1988) Spreading-Activation Phonological and Lexical Encoding

19. Connectionist Models

20. Spreading-Activation and Phonological Errors

21. The CRH and Stuttering • Explanation: Speech disfluencies occur when speakers interrupt ongoing speech to repair errors in their phonetic plan that are detected by their internal speech monitors • Assumption: Individuals who stutter have a problem with their phonological encoding mechanism that leads to frequent phonetic plan errors that must be repaired

22. Delayed Phonological Encoding

23. CRH Summary • Speakers have the ability to monitor their speech -- both before and after it is produced • Speakers sometimes make errors in phonological encoding due to the spreading-activation mechanism • If speakers detect these errors, they can interrupt speech to repair them before they are produced • The by-product of the interruption is a disfluency • People who stutter produce more disfluencies because their phonological encoding mechanism is impaired, so there are more opportunities for repair

24. Product of processinghigh in awareness Processing procedures low in awareness Stress, intonation, duration, and vocal quality PP SYSTEM Vocal signal systemFeeling and intent mapping Integration of paralinguisticandprosodic components WORKINGMEMORYSYSTEM COGNITIVE SYSTEMFormulation of ideas paralinguistic LANGUAGE SYSTEM Symbol System Symbolic Mapping prosody Words forphonemic analysis Syllable Slots Segment order SEGMENTAL SYSTEMPhonetic Specifications INTEGRATOR SYSTEMSegments integrated into syllables Awareness Segments SPEECH MOTOR CONTROL SYSTEM Temporal Dyssynchrony Model(Perkins, Kent, & Curlee, 1991)

25. Temporal Dyssynchrony Model • Speech is the result of many concurrent language and motoric processes • If timing of language processing components is not precise, a breakdown will occur • Perkins also incorporates time pressure • time pressure increases likelihood of the “loss of control” feeling that defines stuttering • without abnormal time pressure, speech disfluencies may occur, but stuttering will not

26. ? ? ? ? What do these models tell us about individual people who stutter?

27. Not Much! Still, language models give us guidelines about what specific aspects of language we should examine in our diagnosis and treatment of children who stutter

28. ? ? ? ? Do children who stutter have language disorders more often than childrenwho do not stutter?

29. Stuttering and Language Disorders • Nippold (1990) found no evidence that children who stutter have more language disorders than children who do not stutter • Still, there may be some language disorders that may contribute to the development of a stuttering problem • Word-Finding Problems • Phonological Disorders

30. L D Ï ¿ Stuttering and Phonological Disorders • Stuttering and disordered phonology co-occur • 30% to 40% of children who stutter also exhibit problems with phonology (compared to 2% to 6% of the general population) • Stuttering and disordered phonology interact. • There seem to be differences in the basic speech behaviors of S+DP and S+NP children • This interaction may affect diagnosis and treatment of stuttering and disordered phonology

31. dog Stuttering and Word-Finding Problems • Word-Finding difficulties may be a factor in as many as 50% of the children evaluated at the NU Speech Clinic (Gregory & Hill, 1993) • Possible Explanation: • Difficulties retrieving words can lead to delays in speech production or errors in lexical access • Delays lead to breakdowns in temporal sequencing of speech production (similar to Perkins model or CRH)

32. Relationships between Stutteringand Language Disorders • The precise relationship is not known • Disordered phonology or word-finding problems do not cause stuttering • many children who stutter exhibit normal phonology or difficulties with word-finding abilities • furthermore, there is no one cause of stuttering • Disordered phonology or word-finding problems may exacerbate stuttering • associated difficulties with intelligibility might increase children’s sensitivity to speaking

33. Relationships between Stutteringand Language Development • Although children who stutter may not exhibit language disorders, they may exhibit subtle difficulties with language development that might contribute to the onset, development, or maintenance of stuttering • Therefore, it is important to thoroughly examine children’s language skills when evaluating children who stutter

34. CONCEPTUALIZER discourse model, situation knowledge, message encyclopedia generation etc. monitoring parsed speech preverbal message FORMULATOR SPEECH- COMPREHENSION SYSTEM grammatical encoding LEXICON lemmas surface structure forms phonological encoding phonetic plan (internal speech) phonetic string ARTICULATOR AUDITION overt speech Levelt’s (1989) “Blueprint for the Speaker”

35. message generation CONCEPTUALIZER Conceptualization monitoring • Basic Message • Does client stutter more on complex messages? • Does client stutter more on utterances with greater propositionality or meaning? • Pragmatic Intent • How does social interaction affect fluency? • Does client stutter more when experiencing greater demands on pragmatic or social interaction skills?

36. FORMULATOR grammatical encoding surface structure phonological encoding FormulationGrammatical Encoding • Does client stutter more in situations which require more complex utterances? • Does client stutter more on syntactically complex utterances? • Does client demonstrate problems with syntactic development which might interfere with fluent speech production?

37. FORMULATOR LEXICON grammatical lemmas encoding forms phonological encoding FormulationLexical Access • Does client exhibit word finding problems that might interfere with speech production? • Does client exhibit frequent mislabelings or nonsystematic speech errors which might interfere with fluent speech production? • Are some words harder to retrieve than others?

38. FORMULATOR grammatical encoding surface structure phonological encoding FormulationPhonological Encoding • Does client frequently produce nonsystematic speech errors which might lead to production self-repairs or speech disfluencies? • Does client have difficulty retrieving the phonological form of utterances (as in the “tip of the tongue” phenomenon)?

39. FORMULATOR phonological encoding phonetic plan (internal speech) ARTICULATOR Formulation Phonological Development • Does client exhibit phonological delay which might indicate a slow-to-develop linguistic formulation system? • Does client exhibit phonological delay which makes communication more difficult and increases sensitivity about his/her speech?

40. Articulation(a hint of motor involvement) • Does child stutter more when using a faster speaking rate? • Does child stutter more when leaving less time for linguistic planning and formulation of utterances? • Does child have difficulties with diadochokinetic (DDK) abilities that might interfere with ability to rapidly and precisely produce speech

41. ? ? ? ? So what does all this mean for stuttering treatment?

42. Treating Stuttering in the Context of Language Development • Understanding how a child’s language development (or language disorder) affects stuttering should help us plan treatment • If a child demonstrates both a language disorder and stuttering, we should treat both disorders simultaneously by combining the methods of language stimulation with fluency facilitation

43. ring Combining Therapy for Disordered Phonology and Stuttering • Incorporate target sounds for remediating the phonological disorder into fluency activities • Model target sounds while modeling ERS(e.g., read a short story loaded with /r/ words) • Play “go fish” while emphasizing ERS or Easier Beginnings and good turn-taking skills. Use words with target sound and minimal pair sound to emphasize contrasts

44. Summary • An increased understanding of the relationship between language and stuttering can help us diagnose and treat individuals who stutter • Language processing models currently being developed should help us better understand one of the factors which may be associated with the onset, development, or maintenance of stuttering • Such models can help us identify aspects of speech and language production that should be considered when evaluating an individual who stutters.