Key Points
Rationale
For example, 30-70% of individuals with ADHD have comorbid learning difficulties, while 44% have autism spectrum disorder (Joshi et al., 2017; Pastor & Reuben, 2008).
Executive functions (EF), the cognitive processes that regulate behavior and thought, are one factor that may account for ADHD heterogeneity.
Studies show between 30-84% of children with ADHD have working memory deficits, 21-27% have inhibitory control deficits, and 35-38% have set-shifting impairments orgeneralized EF deficits(Coghill et al., 2014; Gomez et al., 2014; Kofler et al., 2019; Sonuga-Barke et al., 2010).
However, most previous research on ADHD subtypes focused only on “cool” EF related to non-emotional control (e.g., working memory,inhibitory control), neglecting “hot” EF involved in emotional control (Bergwerff et al., 2019).
The present study aimed to identify and validate ADHD subtypes based on both cool and hot EF deficits, as well as psychopathology profiles.
This dimensional, Research Domain Criteria (RDoC)-based approach can clarify ADHD heterogeneity and inform targeted interventions.
Method
Sample
Statistical analysis
Results
Insight
The findings align with theResearch Domain Criteriaapproach of characterizing mental disorders dimensionally rather than categorically.
Notably, the subgroup with primarily EF deficits showed distinct impairments in learning and life skills compared to the subtype with predominantly externalizing problems.
This highlights the critical role of EF in real-world impairments for a subset of children with ADHD.
It suggests interventions targeting EF, rather than just behavior management, may be key for improved functioning.
Overall, the study demonstrates the utility of data-driven subtyping to parse the complexity of ADHD. The subgroups showed meaningful differences in clinical presentation, functional impacts, and implied treatment needs.
Moving forward, connecting dimensional profiles to genetics, brain imaging, and treatment outcomes can further precision medicine for ADHD.
Strengths
Limitations
Implications
Conclusion
This study identified four subgroups of ADHD based on psychopathology and executive functioning profiles using a novel, dimensional research approach.
The data-driven subtypes showed meaningful differences in clinical presentation, functional impairment, and treatment needs. The findings underscore the importance of characterizing the neuropsychological heterogeneity of ADHD to advance precision medicine.
Overall, the dimensional subtyping provides a model to connect biological mechanisms to behavioral profiles in this multifaceted, impairing neurodevelopmental disorder.
References
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Saul McLeod, PhD
BSc (Hons) Psychology, MRes, PhD, University of Manchester
Saul McLeod, PhD., is a qualified psychology teacher with over 18 years of experience in further and higher education. He has been published in peer-reviewed journals, including the Journal of Clinical Psychology.
Olivia Guy-Evans, MSc
BSc (Hons) Psychology, MSc Psychology of Education
Olivia Guy-Evans is a writer and associate editor for Simply Psychology. She has previously worked in healthcare and educational sectors.
