Studies of children diagnosed with ADHD have shown considerably higher scores on the Anxious/Depressed scale of the Achenbach Child Behavior Checklist,[REF] which implies a comorbidity of ADHD and anxiety.
In studies with rodents, the prefrontal cortex, specifically the medial prefrontal cortex (mPFC) has been implicated in the processing of information lasting from milliseconds to several seconds, while the hippocampus has been implicated in the processing of information for longer time scales - such as minutes to hours [REF].