ASD is difficult to recognize due to complex psychopathology & has a high comorbidity rate, such as with ED. Previous research notes significantly high Glu levels in the ACC of ASD youth, & correlations between Glu levels in the ACC & ED. Glu is the primary excitatory neurotransmitter in the brain. Glu, through activity at NMDA receptors, is crucial for neurodevelopmental processes, including neuronal plasticity & higher cognitive functioning. Over-activation of Glu is associated with excitotoxicity & apoptosis.

To operationalize ED, previous work by our group & others documented a profile of marked elevation of three Child Behavior Checklist subscales (Anxiety/Depression, Aggression & Attention [AAA profile]), which is associated with severe morbidity & dysfunction, including suicidality. Using this AAA profile, we compared dACC Glu levels in ASD subjects with & without ED, & Healthy Controls (HCs).

We measured Glu concentrations in the dACC of 36 HF-ASD adolescents (8-18 years) & age- & sex-matched HCs, using high field proton MRS. HF-ASD subjects were categorized with & without ED, defined by the aggregate score of the AAA profile for ED (N=29). ASD subjects with ED (>180) were separated into those with Severe Emotional Dysregulation (SED) (>210) (N=11) & Deficient Emotional Self-Regulation (DESR) (<210, >180) (N=18).

These results highlight the potential for glutamatergic dysregulation in the dACC to serve as a biomarker of ASD & ED in adolescents.