This finding suggests that emotion dysregulation is a core component of ADHD and may also serve as a pathway leading to the development of the disorder.
However, these characteristics are absent in about 30% of ADHD cases, and they cannot reliably predict how ADHD symptoms will progress over time.
Participants completed assessments of ADHD symptoms using the ADHD scale of the Child Behavior Checklist.
Emotion dysregulation was reported by parents/guardians using the Difficulty in Emotion Regulation Scale.
However, the group with persistent symptoms showed stronger emotion dysregulation scores, indicating that emotion dysregulation can be considered a core symptom of ADHD.
The association between ADHD symptoms one year later and a smaller surface area of the right pars orbitalis region of the inferior frontal gyrus is mediated by emotion dysregulation, according to an analysis of data from the Adolescent Brain Cognitive Development Study (ABCD). According to this research, emotion dysregulation is a fundamental aspect of ADHD and could potentially be a contributing factor in the disorder’s onset. Nature Mental Health published the study.
An inability to focus, excessive impulsivity, and hyperactivity that interferes with day-to-day functioning are hallmarks of attention-deficit/hyperactivity disorder (ADHD), a neurodevelopmental disorder. Organizing activities, controlling impulses, and maintaining focus are all common challenges for people with ADHD. Although symptoms can last into adolescence and adulthood, they usually start in childhood. Because the disorder’s symptoms interfere with expected behaviors in school settings, the diagnosis is typically made when the child first enters school.
Although the causes of ADHD are not entirely understood, it affects roughly 6–7% of children and adolescents. Most people agree that a combination of certain cognitive impairments and motivational dysfunctions causes ADHD. These traits, however, are not present in roughly 30% of ADHD cases, and they are unable to accurately forecast the course of ADHD symptoms over time.
In addition to cognitive impairment and motivational dysfunction, Wenjie Hou and colleagues hypothesized that emotion dysregulation could be a third neuropsychological pathway to ADHD. According to the authors, the anterior cingulate cortex, the amygdala, the orbitofrontal cortex, the inferior frontal gyrus, and the ventral striatum are important brain areas for emotion regulation. Numerous of these areas do not belong to the traditional neural circuits for cognitive control that have been connected to ADHD in other research.
In the ABCD study, a large longitudinal study that tracked the brain development and mental health of 11,877 children from 22 sites across the United States, the researchers examined data from 672 people with ADHD.
The researchers also used data from the ADHD-200 study, which comprised 409 children without ADHD and 263 people with the disorder, to perform a different analysis. On average, the participants in this group were between the ages of 11 and 12.
Using the Child Behavior Checklist’s ADHD scale, participants evaluated their symptoms of ADHD. Seven cognitive tasks were used to measure cognitive functioning, and the Reward Sensitivity Scale, which was modified from the PhenX toolkit, was used to measure motivational dysfunction. The Difficulty in Emotion Regulation Scale was used by parents and guardians to report emotional dysregulation. When the kids in the ABCD group were 13, their emotion dysregulation was evaluated, and at 12, their cognitive and motivational abilities were gathered.
Additionally, the researchers utilized white blood cell counts and magnetic resonance imaging (MRI) data from the ABCD study participants. Data from the Allen Human Brain Atlas was used to analyze gene expression in the cerebral cortex.
According to the findings, there was no correlation between emotion dysregulation and either motivational dysfunction or cognitive performance from the prior year. Emotion dysregulation was more closely linked to the severity of ADHD symptoms in the ABCD group than either cognitive function or motivational dysfunction. Twenty-one percent of the 350 kids with extremely severe symptoms of ADHD showed neither cognitive nor motivational deficiencies. Furthermore, there was no discernible difference between children with remitted ADHD symptoms and those with persistent symptoms in terms of cognitive or motivational assessments. Nonetheless, the group exhibiting persistent symptoms had higher emotion dysregulation scores, suggesting that this may be regarded as a fundamental symptom of ADHD.
Emotion dysregulation has a clear neural correlate, according to an analysis of neuroimaging data. The right orbital portion of the inferior frontal gyrus tended to have a smaller surface area (but not cortical thickness) in children with more severe emotion dysregulation.
According to a statistical model that the researchers tested, a smaller surface area in this area of the brain results in stronger emotion dysregulation, which exacerbates inattention symptoms. Though this pathway is conceivable, the model also shows a direct correlation between inattention and the part of the brain that is not mediated by emotion dysregulation.
Comparable statistical models that relate inattention to the structural features of particular brain regions through cognitive and motivational dysfunction were also found and tested by the researchers.
According to the study’s authors, “we have demonstrated, using a large sample and a second independent clinical sample, that emotion dysregulation is a core symptom and a pathway to ADHD, which may not respond to the current pharmacological treatments for ADHD.”.
The study sheds new light on the neuropsychological causes of symptoms of ADHD. Nevertheless, it is not possible to draw firm conclusions about cause and effect from the study’s design.
