Early elevations of Internalizing and Externalizing problems are often found to predict later problems. To determine how early Internalizing/Externalizing problems might be associated with brain development, Muetzel et al. (2018) analyzed CBCL Internalizing and Externalizing scores obtained at ages 6 and 10 in relation to magnetic resonance imaging (MRI) data at ages 8 and 10 for 845 children participating in the Generation R (R = Rotterdam) longitudinal study.
It was found that elevated age 6 Internalizing and Externalizing scores predicted smaller increases in subcortical gray matter volume and other brain parameters. Of the CBCL DSM-oriented scales, elevated scores on the Attention Problems, Oppositional Defiant Problems, and Affective (now called Depressive) Problems scales also predicted smaller increases in certain brain parameters.
Although early CBCL scores predicted subsequent brain changes, the reverse was not found—i.e., early brain measurements did not predict subsequent changes in CBCL scores. Based on their findings that early CBCL problem scores predicted differences in subsequent brain development, the authors concluded that “While there are undoubtedly underlying neurobiological explanations for the emergence of psychopathology in children . . . psychiatric symptoms in children may also contribute to some of the macro- and microstructural abnormalities reported in the literature” (p. 60).
Reference: Muetzel, R.L. et al. (2018). Tracking brain development and dimensional psychiatric symptoms in children: A longitudinal population-based neuroimaging study. American Journal of Psychiatry, 175, 54-62.