Prefrontal and temporal cortical thickness in adolescents with traumatic brain injury

Aim To investigate the impact of traumatic injury on the developing prefrontal‐temporal adolescent cortex, and correlated brain structural measures with neurocognitive functioning. Method Nineteen adolescents (12 males, 7 females, age range: 11–17y, mean 15y 8mo, standard deviation 1y 7mo, median 15y 11mo) with traumatic brain injury (TBI) were included. Cortical thickness of frontal and temporal lobes was assessed using magnetic resonance imaging. We correlated cortical thickness of prefrontal‐temporal regions with age, time since injury, and neurocognitive functioning, and compared these results with a matched control cohort without TBI. Results We found thinner prefrontal (p=0.039) and temporal cortices (p=0.002) in adolescents with TBI compared to typically developing children. Furthermore, significant age effect was observed on the prefrontal (r=−0.75, p=0.003) and temporal (r=−0.66, p=0.013) cortical thickness in typically developing adolescents, but not in adolescents with TBI. Executive function (measured using the Behaviour Rating Inventory of Executive Function questionnaire, with lower scores meaning higher functioning) was correlated with prefrontal cortical thickness in typically developing adolescents (r=0.72, p=0.009). Opposite trends were found for correlations between cortical thickness and executive function in the TBI and control cohort. Interpretation Structural maturation in typically developing adolescents correlates with functional development: the older the adolescent, the thinner the prefrontal cortex, the better executive function. In adolescents with TBI we observed an opposite trend, that appeared significantly different from the control group: the thinner the prefrontal and temporal cortex, the worse executive functioning.