Genetics & Brain Function
Stuttering is more common in these individuals, suggesting a genetic component.
Who are family members of people who stutter?
This early theory suggested that parents’ negative reactions to normal disfluencies caused stuttering.
What is Johnson’s Diagnosogenic Theory?
Multifactorial models explain stuttering as an interaction of these two main influences.
What are genetic/neurological factors and environmental factors?
These types of reactions from parents or listeners can increase stuttering severity.
What are negative social reactions?
Speech-motor studies reveal that people who stutter have more variability in these aspects of speech movement.
What are spatial and temporal dimensions?
Twin studies suggest that this percentage of monozygotic twins are concordant for stuttering.
What is 70%?
This model suggests stuttering occurs when speech demands exceed a speaker’s abilities.
What is the Demands and Capacities Model?
This term describes how multiple variables interact rather than a single direct cause.
What is a multifactorial explanation?
This term describes the idea that external influences contribute to stuttering’s development but do not directly cause it.
What is an environmental factor?
This theory proposes that stuttering results from disruptions in the timing of neural signals for speech.
What is the Disorder of Timing Theory?
Stuttering is associated with increased activity in this hemisphere of the brain.
What is the right hemisphere?
The Two-Factor Theory combines these two learning principles to explain stuttering.
What are classical and instrumental learning?
A benefit of multifactorial models is that they provide guidance for this group.
Who are parents?
The concept that stuttering can be reinforced due to reduced anxiety is based on this behavioral theory.
What is conditioning (or learned behavior)?
Studies show that people who stutter have inefficient coordination in this key system responsible for producing speech.
What is the speech-motor system?
This term describes the idea that speech dominance is divided between both hemispheres, leading to instability in speech production.
What is cerebral dominance theory?
This hypothesis suggests that stuttering moments arise when the brain attempts to correct errors before they are spoken.
What is the Covert Repair Hypothesis?
A drawback of multifactorial models is that they often lack this key scientific principle.
What is falsifiability?
These types of situational pressures, such as speaking quickly or performing in public, can exacerbate stuttering.
What are communication demands?
This feature of speech-motor control, involving planning and execution, appears less stable in people who stutter.
What is fluency control?
Research has identified possible stuttering-related genes, but evidence remains insufficient to isolate a single genetic cause.
What is the current status of genetic research on stuttering?
The first multifactorial models suggested that no single factor was necessary or sufficient to cause stuttering.
What is the main idea behind early multifactorial models?
The P&A model of stuttering aims to explain the occurrence of these specific speech disruptions.
What are individual stuttering moments?
The Demands and Capacities Model states that stuttering is likely when these exceed a child's abilities.
What are speech and language demands?
Researchers have found that even during fluent speech, individuals who stutter show atypical patterns in this.
What are speech movements?