Working memory-related functional brain patterns in never medicated children with ADHD.
Isabelle Massat1, Hichem Slama, Martin Kavec
1UR2NF - Neuropsychology and Functional Neuroimaging Research at CRCN- Center for Research in Cognition and Neurosciences and UNI - ULB Institute for Neurosciences, Université Libre de Bruxelles (ULB), Bruxelles, Belgium.
Plos One
|November 21, 2012
Summary
Children with Attention Deficit/Hyperactivity Disorder (ADHD) show reduced brain activity in key areas during working memory tasks. This study highlights a distinct neuroanatomical network involved in ADHD, impacting executive functions.
Area of Science:
- Neuroscience
- Developmental Psychology
- Cognitive Science
Background:
- Attention Deficit/Hyperactivity Disorder (ADHD) is a neurodevelopmental disorder with core symptoms of inattention, hyperactivity, and impulsivity.
- Executive functions, particularly working memory (WM), are often impaired in individuals with ADHD.
- Previous research is confounded by medication, comorbidities, and task performance variations.
Purpose of the Study:
- To investigate WM-related brain activity in never-medicated, prepubescent children with ADHD using functional Magnetic Resonance Imaging (fMRI).
- To identify specific cerebral patterns and functional connectivity differences associated with WM processing in ADHD.
- To explore the neuroanatomical basis of WM deficits in ADHD, independent of confounding factors.
Main Methods:
- Functional Magnetic Resonance Imaging (fMRI) was used to record brain activity during a memory updating N-back task.
- Participants included never-medicated, prepubescent children diagnosed with ADHD (without comorbidities) and age-matched controls.
- Analysis focused on WM-related activation levels and functional connectivity patterns within cortico-subcortical networks.
Main Results:
- Children with ADHD demonstrated decreased WM-related activation in a widespread cortico-subcortical network, including occipital, parietal, caudate, cerebellum, and brainstem regions.
- Despite comparable task performance to controls, ADHD participants exhibited distinct functional connectivity patterns.
- Specifically, the cerebellum showed tighter coupling with brainstem areas, such as the red nucleus, during WM updating.
Conclusions:
- ADHD is associated with a core functional neuroanatomical network dysfunction underlying working memory processes.
- These findings provide evidence for a specific neural basis contributing to the pathophysiology and clinical expression of ADHD symptoms.
- The study emphasizes the importance of examining never-medicated individuals to understand intrinsic neural differences in ADHD.
Related Concept Videos
01:30Attention-Deficit/Hyperactivity Disorder
Attention-deficit/hyperactivity disorder (ADHD) is a neurodevelopmental disorder characterized by persistent inattention, hyperactivity, and impulsivity. It affects approximately 5-8% of children globally, with around 60-70% of cases persisting into adulthood. ADHD has significant implications for educational attainment, social interactions, and occupational success.
Diagnostic Criteria and Symptoms
To diagnose ADHD, symptoms must manifest before age 12 and be evident across multiple settings.
Diagnostic Criteria and Symptoms
To diagnose ADHD, symptoms must manifest before age 12 and be evident across multiple settings.
01:30Information Processing Approach
The information-processing theory of cognitive development centers on fundamental mental processes, including attention, memory, and problem-solving skills. Researchers in this field examine how cognitive abilities, such as working memory, evolve and influence children's overall development. Studies indicate that children with stronger working memory tend to excel in reading comprehension, math, and problem-solving compared to peers with less efficient memory skills. Low working memory is also...
01:24Working Memory
Working memory refers to a combination of components, including short-term memory and attention, that allow an individual to hold information temporarily as we perform cognitive tasks. It is an essential cognitive function that enables the execution of complex tasks such as problem-solving, comprehension, and reasoning. Unlike short-term memory, which simply involves the storage of information for a brief period, working memory involves the active manipulation and processing of this information.