Stuttering Brain Structures/Functions and Theories

Corticobulbar tract

White matter pathway transmitting signals from cortices to the midbrain

Basal ganglia

Relay station for processing sensory and motor signals to and from the cortex

Arcuate fasciculus

White matter pathway transmitting signals from Wernicke’s to Broca’s areas

Cerebellum

Coordinates different systems involved in speech production

Cerebellar peduncles

White matter pathways connecting the brainstem to the cerebellum

Frontal cortex

Executive functioning, motor control

Insular cortex

Less well-known but involved in motor, emotional regulation, learning processes

Anterior cingulate cortex

Moderating attention

Demands and capacities theory

If a demand exceeds a child’s capacities for fluent speech, stuttering results

Motor, language, emotion, cognition

Capacities in demands and capacities

Multifactoral dynamic pathways

Brain growth/adaptations in developing interactive neurons networks for speech, language, and emotions

Covert repair hypothesis

Error detected, plan interrupted, new plan initiated

EXPLAN model

Language plan is developed in temporal lobe, motor system executes this plan in the frontal lobe, stalling or pushing forward with an incomplete plan leads to disfluency

Cybernetic and feedback model

Breakdown occurs due to distorted feedback and disfluency results when speaker attempts to correct the error - supports choral reading and delayed auditory feedback

Diagnosogenic theory

Formulated by Wendell Johnson, states that stuttering is a learned anticipatory struggle - the child anticipates a negative reaction and avoids the stutter which leads to more complex stuttering

Britton and Shoemakers Combination Theory

Anxiety caused disruptions in speech that lead to stuttering (classical conditioning), secondary characteristics develop as escape/avoidance behaviors in reaction to stuttering (operant conditioning)