Interactions between Language and Stuttering NU/SFA Workshop for Fluency Specialists July, 1996 J. Scott Yaruss, Ph.D., CCC-SLP University of Pittsburgh

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

Interactive Relationship Between Clinical Research and Clinical Practice

? ?? ? What causes Stuttering?

Factors That May Be Involved in Stuttering GeneticEnvironmental LinguisticMotoric Psychological

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

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

Word-Based Factors Length Familiarity Phonetic Stress Initial Sound Position in Utterance Meaning / Propositionality Phonetic / Phonological Complexity (?)

Utterance-Based Factors Length Grammatical Complexity Pragmatic Intent Meaning / Propositionality Speaking Rate (?)

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

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

? ?? ? How does language development affect stuttering?

Pragmatics:meaning of utterances Semantics:meaning of words Syntax:structure of utterances Morphology:structure of words Phonology:sounds of words Language Systems Approach

Language Model Approach 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

Basic Steps in Language 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

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

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)

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

Connectionist Models

Spreading-Activation and Phonological Errors

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

Delayed Phonological Encoding

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

Temporal Dyssynchrony Model (Perkins, Kent, & Curlee, 1991) SEGMENTAL SYSTEM Phonetic Specifications COGNITIVE SYSTEM Formulation of ideas LANGUAGE SYSTEM Symbol System Symbolic Mapping WORKING MEMORY SYSTEM Awareness Product of processing high in awareness Stress, intonation, duration, and vocal quality PP SYSTEM paralinguistic prosody SPEECH MOTOR CONTROL SYSTEM Segments INTEGRATOR SYSTEM Segments integrated into syllables Syllable Slots Segment order Processing procedures low in awareness Vocal signal system Feeling and intent mapping Integration of paralinguistic and prosodic components Words for phonemic analysis

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

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

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

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

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

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 D Ï L ¿

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) dog

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 Relationships between Stuttering and Language Disorders

Relationships between Stuttering and 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

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

Conceptualization 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? CONCEPTUALIZER message generation monitoring

Formulation Grammatical 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? grammatical encoding phonological encoding FORMULATOR surface structure

Formulation Lexical 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? LEXICON lemmas forms FORMULATO R phonological encoding grammatical encoding

grammatical encoding phonological encoding FORMULATOR surface structure Formulation Phonological 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)?

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? phonological encoding phonetic plan (internal speech) ARTICULATOR FORMULATOR

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

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

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

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 rin g

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.