Wendell Johnson
Fluency & Disfluency
Fluency: The effortless
flow of speech. Flow
includes pauses,
intonation, stress,
rhythm, and rate.
Fluency & Disfluency
Disfluency: A
disruption in the
effortless flow of
speech. We all
produce disfluencies.
Two common
disorders of fluency
are Stuttering and
Stuttering (or Stammering in UK)
A Definition: Occurs when the forward flow
of speech is abnormally interrupted by
repetitions or prolongations of a sound or
syllable, articulatory postures, or by
avoidance and struggle behaviours (Van
Stuttering involves both
overt (observable) and covert
(nonobservable) behaviours.
Famous People Who Stutter
In the Present:
Rowan Atkinson, actor who plays Mr. Bean
Bruce Willis, actor (films include 'Die Hard')
Samuel L. Jackson, actor (films include Star Wars: Episodes 2 and 3)
James Earl Jones, voice of Darth Vader in 'Star Wars'
Sam Neill, actor (films include 'Jurassic Park 3')
Cameron Daddo, actor (Australia's youngest TV Game Show Host at 21)
Gareth Gates, singer in the UK ('Record of the Year' 2002)
Noel Gallagher, guitarist from the rock band Oasis
In the Past:
Marilyn Monroe, (1926-1962) actress
King George VI, (1895-1952), King of England
Winston Churchill, (1874-1965), PM of Britain during World War II
Lewis Carroll, (1832-1898), author of Alice in Wonderland
Charles Darwin, (1809-1882), British naturalist
George Washington, (1732 -1799), first president of the USA
Isaac Newton, (1643-1727), scientist who developed the Law of Gravity
Satirization of Stuttering
Stuttering: Some Characteristics
• Approximately 3% of Preschoolers stutter
• Approximately 1% of school-age and adults
• Stuttering occurs more often in boys (3:1 to 5:1)
• A higher occurrence of stuttering occurs in twins
• More stuttering occurs in children who are
• Some situations raise or lower moments of
Stuttering Behaviours
Primary Stuttering Behaviours:
• Interjections
• Sound/Syllable Repetition
• Word Repetition
• Phrase Repetition
• Audible Sound Prolongation
• Inaudible Sound Prolongation (Block)
• Revision
• Combination of any of the above
Stuttering Behaviours
Secondary Behaviours
• Bodily Movements:
– facial grimaces
– head movements
– loss of eye contact
• Psychosocial Behaviours:
word avoidance
Draw a picture of what it feels like to
stutter: Pre-Teen
Source: Minn State Univ
Draw a Picture of What it feels like
to stutter: Teenager
Draw a picture of what it feels like to
stutter: Teenager
Components of Stuttering Behaviour
Theories of Stuttering
The actual cause of stuttering remains unknown to this
day, in spite of being the most researched disorder in
our profession.
Some of the classic theories regarding the cause of
stuttering are:
• Cerebral Dominance Theory
• Neurotic Theory
• Conditioning Theory
• Diagnosogenic Theory
• Constitutional Theory
Cerebral Dominance Theory
View developed in the 1920’s that stuttering resulted
from either a lack of brain dominance or competing
hemispheres in regard to the production of speech.
Neurosis Theory
View developed in the 1950’s that stuttering occurs in
people because of a deep-seeded unconscious wish to
do so. Developed out of the fields of psychiatry and
Conditioning Theory
View developed in the 1950s that is based on principles
of learning, specifically the notions of “punishment” and
“reinforcement. Stuttering results from a conflict of
opposing drives. A drive to speak (approach) and a
drive to refrain from speaking (avoidance).
Types of Conflict:
Approach ↔Approach
Avoidance ↔ Avoidance
Approach ↔ Avoidance
Diagnosogenic Theory
Very popular theory between 1940-1970.
Based on the notion that stuttering occurs as a
result of an over-reaction or misdiagnosis by
adults. Stuttering develops as a child’s
reactions to the parent’s reaction of his/her
“Stuttering begins not in the child’s mouth
by in the parent’s ear” (W Johnson).
Constitutional Theory
Consists of a number of various theories that have
developed between 1980-present. The essence of
these theories is that the child is predisposed to stutter.
There is a deficit or breakdown in the body that causes
Examples of these theories are:
Genetic Theory: stuttering is found to run in families.
Physiological Theory: stuttering results from impaired
respiration, phonation, and/or articulation.
Development of Stuttering
• The onset of stuttering is between the ages of 2-5
years, with an average of 3-years.
• When stuttering first occurs it is episodic (waxes
& wanes).
• 50% of children are free of stuttering by age 4.
• 75% of children are free of stuttering by age 6.
• By 12-years of age, if no stuttering is observed,
the child is risk-free.
Low & High Risk Disfluencies
Low Risk Disfluencies:
• Interjections
• Revisions
• Phrase Repetitions
• Whole Word Repetitions
High Risk Disfluencies:
• Sound/Syllable Repetitions
• Any Prolongation (audible, inaudible)
Other High Risk Behaviours:
• Bodily Movements
• PsychoSocial Behaviours
Warning signs leading to stuttering in young
children (Van Riper)
5 Myths about Stuttering
Myth 1: People who stutter (PWS)are not smart
Reality: There is no link whatsoever between stuttering
and intelligence.
Myth 2: Nervousness causes stuttering.
Reality: Nervousness does not cause stuttering. Nor
should we assume PWS are prone to be nervous, fearful,
anxious, or shy. They have the same full range of
personality traits as those who do not stutter.
Myth 3: Stress causes stuttering.
Reality: Stress is not the cause, but it certainly can
aggravate stuttering.
Source: ASHA
Myths - continued
Myth 4: Stuttering can be “caught” through imitation or by
hearing another person stutter.
Reality: You can’t “catch” stuttering. The exact cause is
unknown but recent research indicates that family history
(genetics), neuromuscular development, and the
child’s environment, all play a role in the onset of stuttering.
Myth 5: It helps to tell a person to “take a deep breath
before talking,” or “think about what you want to say first.”
Reality: This advice only makes a person more selfconscious, making the stuttering worse. More helpful
responses include listening patiently and modeling slow
and clear speech yourself.