To assess speech abilities in adolescents born preterm and investigate whether there is an association between specific speech deficits and brain abnormalities.
Study design
Fifty adolescents born prematurely (<33 weeks’ gestation) with a spectrum of brain injuries were recruited (mean age, 16 years). Speech examination included tests of speech-sound processing and production and speech and oromotor control. Conventional magnetic resonance imaging and diffusion-weighted imaging was acquired in all adolescents born preterm and 30 term-born control subjects. Radiological ratings of brain injury were recorded and the integrity of the primary motor projections was measured (corticospinal tract and speech-motor corticobulbar tract [CST/CBT]).
Results
There were no clinical diagnoses of developmental dysarthria, dyspraxia, or a speech-sound disorder, but difficulties in speech and oromotor control were common. A regression analysis revealed that presence of a neurologic impairment, and diffusion-weighted imaging abnormalities in the left CST/CBT were significant independent predictors of poor speech and oromotor outcome. These left-lateralized abnormalities were most evident at the level of the posterior limb of the internal capsule.
Conclusion
Difficulties in speech and oromotor control are common in adolescents born preterm, and adolescents with injury to the CST/CBT pathways in the left-hemisphere may be most at risk.
CBT
Corticobulbar tract
CST
Corticospinal tract
cUS
Cranial ultrasound scanning
DWI
Diffusion-weighted imaging
FA
Fractional anisotropy
FOC
Focal Oromotor Control
FSIQ
Full-scale IQ
HPI
Hemorrhagic parenchymal infarction
IVH
Intraventricular hemorrhage
MRI
Magnetic resonance imaging
PLIC
Posterior limb of the internal capsule
VMPAC
Verbal Motor Production Assessment for Children
Cited by (0)
Supported by Action Medical Research UK (SN4051) and the Garfield Weston Foundation, which had no involvement in study design, the collection, analysis, and interpretation of data, the writing of the report, or the decision to submit the paper for publication. The authors declare no conflicts of interest.