Stuttering Flashcards
Define Stuttering
Stuttering is a disruption in the fluency of verbal expression which is characterised by involuntary audible or silent repetitions or prolongations in the utterance of short speech elements. Namely sounds, syllables or words of one syllable.
What are the observable features of stuttering
- Repetitions of whole words, initial sounds and part words
- Prolongations
- Blocks
- Non Verbal: Facial and Body movements
What are the unobservable features of stuttering
- Negative emotions
- Word Avoidance
- Word Revision
What is the Epidemiology of Stuttering
Study of Rates of diseases in populations and the consideration of how these rates are affected by variables such as age, gender and social class- Allows for accountability and planning caseload of management decisions
Incidence?
Number of New cases of disorder (4-5%)
Prevalence?
Percentage of cases at any given time: One percent of the population
Gender?
4:1 ratio males to females
Spontaneous Recovery
10% recovery
Age of Onset
Onset between 2.6 and 3.6 years of age
Episodic Nature
Fluctuate significantly in preschool years, 10% sudden onset
Factors that Modify stuttering
Situational Reactivity (changes due to situation- occupation and socialising
Measurement Reactivity:
Assessment trigger/ recording device
Discriminative Stimuli
Adaptation effect: Repetition
Response Contingent Stimulation
Modified Vocalisation Hypothesis: Chorus Reading/Shadowing, speaking with an accent, singing, whispering, white noise/ delayed auditory feedback
Measurement Situations
Beyond clinic measurements
Within clinic Measurements
Covert Measurement (reactive to assessment, reduced or increased by discriminative stimuli- important to consider ethics and informed consent)
Molecular Measures (objective)
%SS- no of stutter/no of syllables SPM no of stutters/time SMST stutters per min of speech time Mean number reps Mean duration of stuttered episodes
Molar Measures (subjective)
Severity rating scale
Speech naturalness
(Internal perceptual threshold judgement)
Family Aggregation Studies
Yale Study Demonstrates “Single major locus vs polygenic transmission’
High Density families (30-60%) of pro bands have a positive family history
-Gender issues
-Sib Ship rankings (inherited dispositions no mimicry/environmental causes)
Twin Studies
Increased Concordance in monozygotic twins compared to dyzygotic indicates increase strength of genetic factors
- 10/16 monozygotic pairs
- 3/14 dyzyogotic pairs both stuttered
Sex Linked Studies
Males have a higher probability when linked to affected female parent (67%) , questions regarding transient recovery vs persisted stuttering is genetically linked
Linkage Analysis
Methodology determines the location of a specific causative gene on a known chromosome- very complex patterns of inheritance (chromosome 9 and 15 emerged strongly)
Biological Genetics
Attempt to find a gene relationship trait
Candidate gene analysis uses smaller location identified on genes known to have similar characteristics- larger amount of chromosomes to be analysed at once
Association Studies
International collaborative DNA research grant “in search of genes for stuttering”
Aim: To identify genetic variation affecting susceptibility to stuttering through association functional mapping
-Genes are yet to be identified though studies confirm genetic trends in transmission among family members
Clinical Implications to genetic research
Inform parents stuttering is familial disorder
Does not require genetic counselling offered for serious diseases
environmental influences can play a part in assisting recovery, reducing symptoms and facilitating fluency
Emphasise effectiveness of treatment in childhood as close to onset as possible
What are the three Aetiological hypotheses
Psychogenic Theory
Learning Theory
Organicity Theory
What is the Psychogenic Theory
Stuttering is the breakdown in normal ongoing psychological function, resultant from abnormal personality
-Research investigated parent aspirations (Over-protectivness) and anxiety in children and adults
Did not find significant patterns
What is the learning theory
Stuttering as a learned Behaviour resulting from negative reactions to normal childhood disfluencies
What are the components of the learning Theory?
Diagnosogenic Theory
Anticipatory Theory
Operant or Instrumental Learning theory
Demands and capacity hypothesis
What is the diagnosogenic theory?
Stuttering begins not in the child’s mouth but in the parents ear- stuttering avoidance reactive motivated by anxious anticipation of speech interruption by the child and negative labelling by the parent
What is the Anticipatory Theory?
People who stutter interfere with speech patterns because of a learned belief in difficult of speech and anticipation of speech failure
What is the operant or Instrumental learning theory?
Stuttering is learned and maintained under reinforcement schedule in child environment
What is the demands and capacity hypothesis?
Stuttering results when demands of fluency from social environment exceed cognitive, linguistic, motor or emotional capacity for speech
What are the components of Organicity theory?
Cerebral Dominance EEG Cybernetic models of stuttering Laryngeal Reaction Time Manual Reaction times Stuttering as a prosodic disorder Speech motor control theory
Cerebral Dominance?
Confused cerebral dominance and handedness
EEG?
Abnormal alpha rhythms and electrical activity were thought to cause stuttering; no differences found at rest.. EFFORT?
Cybernetic models of stuttering?
Servo system feedback mechanisms were though to be defective, experiments were conducted with masking noise and delayed auditory feedback
- Edinburgh masker: Stuttering decrease under high level of white noise (50-60db)
- DAF and found under specified delay periods (150-200) milliseconds people who stuttered increased loudness, used monotone, prolonged rate, increased pitch became fluent- effects persisted after delay was eliminated (normal speakers under DAF displayed disfluencies
Laryngeal Reaction time
Slower vocalisation onset time in individuals who stuttered in response to auditory signal
Manual Reaction time
No difference in button pressing and non speech vocalisation times
Stuttering as a prosodic disorder
Stuttered episodes on specific loci of information units in speech e.g. nouns adjective and personal pronouns
-These word classes received stress in english stressed syllables are achieved by changes in vocal control and laryngeal functioning
Speech Motor Control Theory?
Investigation of velocity, displacement and duration of movement and coordination of timing between articulatory events specifically: physiological conditions associated with speech breakdown and condition which make people who stutter vulnerable to speech breakdowns
What is effortful control?
Self regulatory trait representing voluntary and executive functions of temperament
^ displays regulation of behaviour attention have lower stuttering severity ratings
less have a high stuttering severity rating
teach parents to increase resilience and self regulation in children.
