Etiology

1. Etiology • Theories • 1. Organic, Constitutional, or Medical • 2. Neurotic • 3. Behavioral or Learned

2. . Organic, Constitutional, or Medical • Theories • 1. Cerebral Dominance • 2. Biochemical • 2. Laryngeal Dynamics • 3. Heredity • 4. Middle Ear Dysfunction • 5. Neurological Functioning

3. 1. Theory of Cerebral Dominance • Theories: Orton and Travis • Fact: more stutterers are left handed • Supporting Research • Moscovitch (1973) asserts that the right hemisphere in right-handed people maintains some limited underlying ‘verbal competence’ • Geschwind limit of this verbal competence ‘depends on the degree to which the dominant hemisphere can control the verbal behavior of the minor hemisphere via midline commissures and other pathways” • Tenant: • defective ‘motor lead control’ or incomplete cerebral dominance • remediation: change handedness

4. 2. Laryngeal Dynamics’ Theory • Theorist: Adams • Stutterers have longer VOT, SIT (speech initiation times) VIT (voice initiation times) • describes characteristics • does not identify causal components of disorder,

5. 3. Biochemical • Theorist: West • Compared to a mild form of epilepsy • term: dsyphemia • Current Research: Dopamine • Questions? • Cause or effect

6. 6. Middle Ear Dysfunction • Theorist: Webster • Non-synchronized middle ear muscle firing which means there are non-synchronized messages to the brain

7. 4. Heredity Model Theory • Theorists: Kidd, Goldberg, Wepman • Facts: stuttering runs in families, 8-15% • 65-70% had stuttering relatives • twinning studies • more stuttering in monozygotic twins, risk 77% • Stuttering is determined by many factors, the factors are both hereditary and environmental and it affects the sexes differently • related to a THRESHOLD MODEL

8. 5. Neurological Functioning • Theorist: Perkins • use of Positron Emission Tomography (PET) scans • there is a neurophysical difference at the moment of stuttering • Current research: role of Prefrontal Cortex • Function: • Question: cause or effect?

9. III. Learning Theories • 1. Diagnosogenic • 2. Two-Factor • 3. Approach-Avoidance • 4 Capacities/Demands • 5. Anticipatory/Struggle

10. 1. Diagnosogenic Theory • Wendell Johnson, 1940’s • Tenants: • a diagnosogenic disorder is one that is caused by its diagnosis • person’s behavior is labeled as ______ and _____ • dysfluency in the ‘ear of the beholder’ • listener (PARENT) reinforced s=through negative reinforcement which parent believes in punishment

11. Diagnosogenic Theory continued • 3 Behaviors that must occur • 1. Child repeats or hesitates while speaking • frequency is not a critical variable • 2.listener ‘diagnoses’ repetitions as abnormal and react accordingly • “stop and start over • thinking for what you are saying before you say it • take a deep breath before you start • talk more slowly • non-verbal response such as looking away • 3. Child becomes concerned and tries not to be dysfluent • attends more to the dysfluencies than previosly and becomes upset when they occur

12. 2. Two Factor Theory • Theorist: Brutten and Shoemaker • Stuttering results from the interaction of genetic and environmental factors • Factor I behaviors result from emotional learning • classically conditioned • modified either though reconditioning or counterconditioning • reconditioning involved returning a conditioned stimulus to its previous neutral status • repeated presentations of the conditioned stimulus without negative consequences • ex: salesperson

13. Factor I Classical Conditioning Cont. • counterconditioning-learning new responses to a conditioned stimulus • repeated presentation of the conditioned stimulus in various negative emotion producing situations in a hierarchy

14. Two Factor Theory: Factor II • Factor II behaviors learned through operant conditioning • instrumental responses operantly conditioned over the years • developed in an attempt to prevent or reduce the severity of stuttering • secondary behaviors • reduced through reinforcement, nonreinforcement or punishment • reinforcement of fluency enhancing behaviors results in elimination

15. 3. Approach-Avoidance Theory • Sheehan • Tenant • conflict arises in which the motivational drives subserving both approach and avoidance are simultaneously aroused • when the APPROACH drive is dominant, fluent speech • when there is Avoidance BUT the speaker speaks, then….. • Origins in learned speech anxieties and/or unconscious personally factors

16. 4. Capacities/Demands Theory • Starkweather • Tenants • capacities for fluent speech-motoric,cognitive, linguistic skills that make speech easy for most children-interact with demands for fluency placed on child by the external communicative environment and by child himself • as capacity for fluency grows, expectations of parent and child also increase • capacities and demands are increasing as a function of age

17. 5. Anticipatory Struggle Hypothesis • Bloodstein • Tenants: • disorder maintained by anticipating stuttering and then struggling to avoid it

18. III Neurotic Theory • 1. Glauber • 2. Bloom • 3. Frustration Theory

19. Neurotic Theory Concepts • Stuttering as a type of neurosis • stutter because they attempt to cope with some type of repressed (unconscious) neurotic need in a way that allows them to be dysfluent • hypotheses look upon stuttering as being both a symptom of an unsatisfied repressed emotional need AND purposeful behavior

20. 1. Neurotic Theory: Glauber • Stuttering behaviors -symbolic of the repressed need • Repressed need for: • infantile need for oral erotic gratification • infantile need for anal erotic gratification • stuttering represents anal movements “displaced upwards”

21. 2. Neurotic Theory: Bloom • Aggressive expression of hostile feelings person is afraid to express openly • stutterer makes those with whom he/she speaks uncomfortable • assumes stuttering is ‘painful’ for the listener

22. Neurotic Theory Thoughts • For many stutterers, stuttering is non-symptomatic • does not cluster with other problems • Neither stutterers or their parents show no greater evidence of neurotic symptoms than the population

23. Etiology Questions • What is Peters and Guitars’ theory of causality • What is yours? • Which one/s have you discounted • What is “the point” of so many causation theories?

24. End of Lecture Notes The door is open to …..