Ritalin Paper Database
Light
Visual Abstract
Executive functions and methylphenidate response in subtypes of attention-deficit/hyperactivity disorder
Executive functions and methylphenidate response in ADHD subtypes
August 27, 2024
author
O'Driscoll GA, Dépatie L, Holahan AL, Savion-Lemieux T, Barr RG, Jolicoeur C, Douglas VI
journal
Biol Psychiatry
Date Published
2005 Jun 1
Why link to a visual abstract?
What is a visual abstract?
Visual Original
Study Summary
🔬
What They Studied
The study aimed to investigate the impact of methylphenidate on executive functions in boys with two subtypes of ADHD compared to a control group.
💡
What They Found
The study found that ADHD-combined boys showed impairments in motor planning and response inhibition but not in task switching, while ADHD-inattentive boys did not. Methylphenidate improved performance in both subtypes.
📚
What This Means
These results suggest that methylphenidate (Ritalin, Concerta) improves certain executive functions in boys with ADHD, aligning with evidence supporting its effectiveness in treating ADHD symptoms.
Study Summary
Study Overview
This study explored neurological differences between two ADHD subtypes—Combined (ADHD-C) and Inattentive (ADHD-I)—and their impact on executive functions like motor planning. Using oculomotor tasks, researchers aimed to determine if these subtypes represent distinct disorders or variations of the same condition.The findings highlight the unique challenges each subtype faces, suggesting ADHD-C involves greater motor control deficits, leading to more tailored treatment approaches.
Abstract: background
Oculomotor tasks are a well-established means of studying executive functions and frontal-striatal functioning in both nonhuman primates and humans. Attention-deficit/hyperactivity disorder (ADHD) is thought to implicate frontal-striatal circuitry. W...more
Unique Study Methodology
"The present study is the first to use oculomotor tests of executive function to evaluate subtype differences. It constitutes an advance over previous neuropsychological research on subtypes by providing well-designed control tasks for the executive function tasks (thus isolating the functions of interest) and by evaluating groups that are essentially free of comorbid disorders and are similar in age, socioeconomic status, and IQ."
Significance of the Findings
"The study's findings add to the understanding of the neurological basis of ADHD subtypes, providing further evidence that ADHD-C and ADHD-I may represent distinct disorders rather than subtypes of the same disorder."
Neurological Basis of ADHD-C
"Our findings support the hypothesis that the ADHD-C subtype has more robust deficits in motor planning and response inhibition compared to ADHD-I."
Study Summary
Methods
Boys aged 11.5-14 were split into ADHD-combined (10), ADHD-inattentive (12), and control (10). Each group completed eye movement tasks testing motor planning, response inhibition, and task switching.Predictive saccades assessed motor planning, antisaccades measured response inhibition, and mixed saccade-antisaccade tasks evaluated task switching. These tests reveal how well the brain plans, inhibits, and switches tasks.
Abstract: methods
Subjects were boys, aged 11.5-14 years, with ADHD-combined (n = 10), ADHD-inattentive (n = 12), and control subjects (n = 10). Executive functions assessed were motor planning (tapped with predictive saccades), response inhibition (antisaccades), and...more
Study Summary
Results
Boys with ADHD-combined had more difficulty with motor planning and response inhibition than controls, but no task-switching issues. ADHD-inattentive boys did not show these challenges. The ADHD-combined group had fewer predictive saccades and struggled with antisaccade tasks. Methylphenidate (Ritalin, Concerta) improved motor planning and response inhibition in both subtypes, but ADHD-C showed more pronounced deficiencies without treatment.
Abstract: results
The ADHD-combined boys were impaired relative to control subjects in motor planning (p < .003) and response inhibition (p < .007) but not in task switching (p > .92). They were also significantly impaired relative to ADHD-inattentive boys, making few...more
Study Summary
Conclusions
Boys with ADHD-combined showed more deficits in motor planning and response inhibition than ADHD-inattentive boys and controls. These deficits suggest distinct brain functions related to hyperactivity and impulsivity.Methylphenidate improved performance in both subtypes, indicating its broad effectiveness in treating ADHD symptoms, even in children without severe executive function deficits.
Abstract: conclusions
ADHD-combined but not ADHD-inattentive boys showed impairments on motor planning and response inhibition. These deficits might be mediated by brain structures implicated specifically in the hyperactive/impulsive symptoms. Methylphenidate improved ocu...more
Background Information
Patient Guide
💊
Methylphenidate Overview
A central nervous system stimulant mainly used to treat ADHD and narcolepsy.
🧠
Action Mechanism
Blocks reuptake of norepinephrine and dopamine, increasing their concentration in the synaptic cleft.
👨⚕️
Primary Uses
Methylphenidate is FDA-approved for treating ADHD in children and adults, and as a second-line treatment for narcolepsy.
🧒
Age Limit for Prescription
Children must be six years or older to be prescribed methylphenidate for ADHD.
💊
Tablets Formulations
Available in immediate-release, extended-release, and sustained-release formulations, among others.
Professional Guide
Expert Opinion: Executive functions and methylphenidate response in ADHD subtypes
Professional guidelines support methylphenidate for managing core ADHD symptoms in children and adolescents, showing an effect size around 1.0.Behavioral therapy combined with medication may enhance treatment, but response to stimulants varies, requiring close monitoring. Guidelines stress medication coverage for adolescents with ADHD to ensure safe driving.
Evidence Summary
How Methylphenidate Enhances Attention by Boosting Brain Chemicals
Methylphenidate boosts levels of certain brain chemicals in the prefrontal cortex, resulting in better attention and focus. This mechanism sheds light on why some medications are effective in treating attention disorders.
The increase in these brain chemicals directly links to improvements in focus, making sense of its beneficial effects for individuals with attention issues.
This effect aligns with improved motor planning and response inhibition observed in boys with ADHD on medication.
The increase in these brain chemicals directly links to improvements in focus, making sense of its beneficial effects for individuals with attention issues.
This effect aligns with improved motor planning and response inhibition observed in boys with ADHD on medication.
Evidence Summary
Methylphenidate Boosts Working Memory Beyond ADHD Treatment
Methylphenidate, commonly prescribed for ADHD, improves working memory, benefiting learning and problem-solving. Research shows that this medication's effects extend beyond treating ADHD symptoms.
This drug enhances working memory, which plays a key role in tasks like learning new information and solving complex problems, thus highlighting its broader cognitive benefits.
This drug enhances working memory, which plays a key role in tasks like learning new information and solving complex problems, thus highlighting its broader cognitive benefits.
Evidence Summary
How Methylphenidate Enhances Focus in ADHD
Methylphenidate, a medication used for treating ADHD, boosts cognitive functions such as attention, focus, and mental performance. Research indicates that individuals diagnosed with ADHD experience significant improvement in these areas when taking the drug.
The medication primarily targets symptoms like inattention and hyperactivity, enhancing overall cognitive efficacy. It's often prescribed to manage ADHD symptoms effectively, backed by scientific evidence.
The medication primarily targets symptoms like inattention and hyperactivity, enhancing overall cognitive efficacy. It's often prescribed to manage ADHD symptoms effectively, backed by scientific evidence.
Evidence Summary
Time Awareness in ADHD: Motivation and Memory Effects
The study aimed to determine if children with ADHD struggle with time awareness due to a genuine deficit or motivational issues. Thirty children with ADHD and 30 control children participated in tasks designed to measure time reproduction with varying motivational incentives. Children with ADHD performed better when more motivated but still lagged behind controls. Additional tests showed significant differences in working memory and behavioral inhibition between the groups.
These findings illustrate how motivation impacts time reproduction ability in children with ADHD. The differences in working memory and behavioral inhibition also play a significant role in their overall performance on these tasks.
These findings illustrate how motivation impacts time reproduction ability in children with ADHD. The differences in working memory and behavioral inhibition also play a significant role in their overall performance on these tasks.
