Thalamocortical connections are: essential for brain function, established early in development, and significantly impaired
following preterm birth. Impaired cognitive abilities in preterm infants may be related to disruptions in thalamocortical
connectivity. The aim of this study was to test the hypothesis: thalamocortical connectivity in the preterm brain at term-equivalent is
correlated with cognitive performance in early childhood. We examined 57 infants who were born <35 weeks gestational age (GA) and
had no evidence of focal abnormality on magnetic resonance imaging (MRI). Infants underwent diffusion MRI at term and
cognitive performance at 2 years was assessed using the Bayley III scales of Infant and Toddler development. Cognitive scores at
2 years were correlated with structural connectivity between the thalamus and extensive cortical regions at term. Mean
thalamocortical connectivity across the whole cortex explained 11% of the variance in cognitive scores at 2 years. The inclusion
of GA at birth and parental socioeconomic group in the model explained 30% of the variance in subsequent cognitive
performance. Identifying impairments in thalamocortical connectivity as early as term equivalent can help identify those
infants at risk of subsequent cognitive delay and may be useful to assess efficacy of potential treatments at an early age.