Neural subtypes in developmental stuttering.

Area of Science:

• Neuroscience
• Developmental Disorders
• Speech Pathology

Background:

• Developmental stuttering is a complex neurodevelopmental disorder with varied individual presentations.
• Heterogeneity in stuttering suggests underlying differences in neural mechanisms.

Purpose of the Study:

• To investigate individual-specific structural brain differences in children who stutter (CWS).
• To subtype CWS based on neuroanatomical profiles using normative modeling.
• To explore the relationship between neural subtypes and stuttering severity and recovery.

Main Methods:

• Applied normative modeling to MRI-derived gray and white matter volumes from 235 CWS and 240 fluent controls (ages 3-12).
• Quantified individual brain deviations from a reference population.
• Clustered CWS into subtypes based on neuroanatomical deviation maps.

Main Results:

• Identified four distinct neural subtypes of CWS with unique structural brain atypicalities.
• One subtype showed basal ganglia-thalamo-cerebellar involvement linked to higher severity and lower recovery.
• A white matter subtype exhibited mild severity and higher recovery likelihood; other subtypes involved the cerebellum and sensorimotor regions.
• Cerebellar atypicalities were a common feature across all four subtypes.

Conclusions:

• Individual-specific neuroanatomical analysis and subtyping reveal heterogeneity in developmental stuttering.
• Cerebellar alterations may be a shared neuroanatomical characteristic of stuttering.
• This approach provides valuable insights for understanding stuttering and may guide future interventions.