Brain morphometry of toddlers with language delay: An exploratory study

While studies have documented neural correlates of language delay in toddlers with developmental conditions, those at genetic risk for language delay, and those born premature, no studies have examined neural correlates in toddlers exhibiting early language delay without known etiology. This study examines brain morphometry in toddlers with and without early language delay. To do so, we collected magnetic resonance imaging on toddlers with language delay (LD; n=7, M_age=19.67 months, 3 female, 2 Hispanic, 4 non-caucasian) and a typically developing (TD; n=17, M_age=22.73 months, 8 female, 2 Hispanic, 3 non-caucasian) comparison group. Exploratory analyses examined group differences in total brain volume, cortical thickness, and cortical surface area using both a whole-brain and region of interest (Broca's and Wernicke's areas) approach. Results showed no gross brain anatomical differences between groups. However, there were group differences in cortical surface area in the temporal cortex (including Wernicke's area and left middle temporal gyrus, hedges' g= -.35) and Broca's area thickness. Results are reported using multiple analytic methods, age matching, and exclusion of children later diagnosed with autism. While this exploratory study has a limited sample size, it provides novel findings that can be utilized to guide hypothesis-driven imaging studies on toddler language delay.