![Image](https://www.worldsupporter.org/sites/default/files/styles/medium/public/tips_suggestions/wereldbol_summaries_joho_single_boek_1_150x190px.png?itok=rEljlfYL)
Executive functions (EF) are neurocognitive processes that maintain an appropriate problem solving set to attain a future goal. The executive functions represent cognitive inputs that facilitate decision making. They do that by maintaining information about possible choices in the working memory, while integrating this knowledge with information about the current context to identify the optimal action for the situation.
Some scientists say that the symptoms of attention-deficit/hyperactivity disorder (ADHD) are the result of a primary deficit in a specific EF domain. They base this hypothesis on the observation that prefrontal lesions sometimes produce behavioral hyperactivity, distractibility, or impulsivity, as well as deficits on EF tasks.
For EF weaknesses to be considered the primary deficit in ADHD at least four criteria must be met:
Groups with ADHD must consistently exhibit weaknesses on EF measures.
EF weaknesses must account for a substantial proportion of the variance in ADHD symptoms in the population.
EF weaknesses must be present in most individuals with ADHD.
EF weaknesses and ADHD symptoms must be attributable to common etiologic influences.
Executive functions and ADHD measures
EF tasks comprise at least four factors, namely response inhibition and execution, working memory and updating, set-shifting and task-switching, and interference control. Also, most models distinguish between verbal and spatial working memory. Many also include additional processes, such as planning and organization, vigilance, and visuospatial orienting. Concerning ADHD they identified thirteen measures that were frequently used in previous research as important measures of ADHD.
Results
The results show significant differences between groups with and without ADHD. ADHD seems to be associated with weaknesses in several key EF domains. However, the results need to be interpreted carefully. The results may be influenced by differences in sampling procedures, the diagnostic criteria that are being used, and which control variables are being used. With regards to these concerns, the following conclusions can be drawn:
Sampling methods and diagnostic algorithms do not affect the results.
With regards to ADHD-subtypes, the results suggest that the hyperactive-impulsive type is associated with minimal executive impairment. This means that the hyperactive-impulsive type possibly doesn’t have the same cause as the combined type. Also, the EF weaknesses seem to be primarily associated with DSM-IV inattention symptoms rather than hyperactivity-impulsivity symptoms.
Some say that results should always be controlled for intelligence, academic achievement, and comorbidity. However, suffering from ADHD may cause impairments in those variables, making it difficult to determine causality. It is therefore difficult to come to a conclusion, although several studies have shown that even with the use of control variables, the results are significant.
Conclusion
The results indicate that executive function weaknesses are significantly associated with ADHD. However, they do not mean that weaknesses in executive functions are the only cause of ADHD. Instead it seems that executive function weaknesses are one of several causes. Models are appearing that try to integrate several possible causes and try to account for the neuropsychological heterogeneity of ADHD.
Future research
Future research may clarify the relationship between executive functions and ADHD and may lead to a more comprehensive model of ADHD. Three directions are recommended. First of all the authors recommend an evaluation of the psychometric characteristics of executive function tasks. The future studies should use tasks with existing reliability data, or carefully assess the reliability of each task. Secondly, the structure of executive functions should be clarified. Many of the executive tasks involve the use of multiple neurocognitive processes. Future studies should attempt to develop tasks that are better able to isolate specific structures of executive functions. Lastly, competing neuropsychologic theories should be directly tested to integrate different theoretical perspectives.
- 1 of 2158
- next ›
JoHo can really use your help! Check out the various student jobs here that match your studies, improve your competencies, strengthen your CV and contribute to a more tolerant world
Online access to all summaries, study notes en practice exams
- Check out: Register with JoHo WorldSupporter: starting page (EN)
- Check out: Aanmelden bij JoHo WorldSupporter - startpagina (NL)
How and why would you use WorldSupporter.org for your summaries and study assistance?
- For free use of many of the summaries and study aids provided or collected by your fellow students.
- For free use of many of the lecture and study group notes, exam questions and practice questions.
- For use of all exclusive summaries and study assistance for those who are member with JoHo WorldSupporter with online access
- For compiling your own materials and contributions with relevant study help
- For sharing and finding relevant and interesting summaries, documents, notes, blogs, tips, videos, discussions, activities, recipes, side jobs and more.
Using and finding summaries, study notes en practice exams on JoHo WorldSupporter
There are several ways to navigate the large amount of summaries, study notes en practice exams on JoHo WorldSupporter.
- Use the menu above every page to go to one of the main starting pages
- Starting pages: for some fields of study and some university curricula editors have created (start) magazines where customised selections of summaries are put together to smoothen navigation. When you have found a magazine of your likings, add that page to your favorites so you can easily go to that starting point directly from your profile during future visits. Below you will find some start magazines per field of study
- Use the topics and taxonomy terms
- The topics and taxonomy of the study and working fields gives you insight in the amount of summaries that are tagged by authors on specific subjects. This type of navigation can help find summaries that you could have missed when just using the search tools. Tags are organised per field of study and per study institution. Note: not all content is tagged thoroughly, so when this approach doesn't give the results you were looking for, please check the search tool as back up
- Check or follow your (study) organizations:
- by checking or using your study organizations you are likely to discover all relevant study materials.
- this option is only available trough partner organizations
- Check or follow authors or other WorldSupporters
- by following individual users, authors you are likely to discover more relevant study materials.
- Use the Search tools
- 'Quick & Easy'- not very elegant but the fastest way to find a specific summary of a book or study assistance with a specific course or subject.
- The search tool is also available at the bottom of most pages
Do you want to share your summaries with JoHo WorldSupporter and its visitors?
- Check out: Why and how to add a WorldSupporter contributions
- JoHo members: JoHo WorldSupporter members can share content directly and have access to all content: Join JoHo and become a JoHo member
- Non-members: When you are not a member you do not have full access, but if you want to share your own content with others you can fill out the contact form
Quicklinks to fields of study for summaries and study assistance
Field of study
- All studies for summaries, study assistance and working fields
- Communication & Media sciences
- Corporate & Organizational Sciences
- Cultural Studies & Humanities
- Economy & Economical sciences
- Education & Pedagogic Sciences
- Health & Medical Sciences
- IT & Exact sciences
- Law & Justice
- Nature & Environmental Sciences
- Psychology & Behavioral Sciences
- Public Administration & Social Sciences
- Science & Research
- Technical Sciences
Add new contribution