METABOLITE CONCENTRATIONS IN THE ANTERIOR CINGULATE CORTEX: A STUDY OF CHILDREN WITH ATTENTION-DEFICIT HYPERACTIVITY DISORDER AND OBSESSIVE-COMPULSIVE DISORDER

Abstract

The dorsal anterior cingulate cortex (ACC) plays an important role in attention and cognitive control (Bush et al., 2000; Margulies et al., 2007; Shackman et al., 2011). Individuals with neurodevelopmental disorders often struggle with inattention, hyperactivity, and repetitive behaviours, which is indicative of deficits in the ACC (Baribeau et al., 2015; Bush et al., 1999; Fitzgerald et al., 2005). This study investigated metabolite abnormalities in the ACC of two groups of children with neurodevelopmental disorders. Participants were children with obsessive-compulsive disorder (i.e., OCD; n = 24) and children with attention-deficit hyperactivity disorder (ADHD; n = 29). Participants completed cognitive and clinical testing and proton magnetic resonance imaging (1H-MRS) of the ACC. Children with ADHD had higher concentrations of N- acetyl aspartate than those with OCD. In the OCD group, creatine concentrations were correlated with scores on the Children’s Yale-Brown Obsessive-Compulsive Scale (CY- BOCS). Across diagnostic groups, concentrations of N-acetyl aspartate predicted scores on the anxious/depressed syndrome scale of the Child Behaviour Checklist (CBCL), and creatine, myo-inositol, and glutamate concentrations predicted scores on the affective problems syndrome scale of the CBCL. This study was the first to compare two groups of children with neurodevelopmental disorders using 1H-MRS, and the first to look the relationship between metabolites and symptom dimensions (i.e., CBCL syndrome scales) rather than the relationship between metabolites and symptom severity alone. Our findings support an interdisciplinary approach to studying neurodevelopmental disorders, and invite future investigations combining 1H-MRS with anatomical and functional imaging techniques.