Functional connectivity of frontal cortex in healthy and ADHD children reflected in EEG coherence
Michael Murias1, James M Swanson, Ramesh Srinivasan
1Autism Center, Center on Human Development and Disability, University of Washington, Seattle, WA, USA.
Insights
Attention-deficit hyperactivity disorder (ADHD) in children shows altered brain connectivity. ADHD subjects exhibited distinct patterns of elevated and reduced brainwave coherence, suggesting underlying neural differences.
Area of Science:
- Neuroscience
- Developmental Psychology
- Child Psychiatry
Background:
- Abnormal functional brain connectivity is implicated in developmental disorders.
- Cognitive dysfunction is a hallmark of many neurodevelopmental conditions.
- Understanding brain connectivity in attention-deficit hyperactivity disorder (ADHD) is crucial.
Purpose of the Study:
- To investigate functional brain connectivity differences in children with ADHD compared to controls.
- To analyze electroencephalography (EEG) data using spectral power and coherence methods.
- To explore the impact of visual stimulation and medication status on brain connectivity.
Main Methods:
- Dense array electroencephalography (EEG) data recorded for 10 minutes per subject.
- Analysis of spectral power and coherence in specific frequency bands (e.g., alpha band).
- Comparison between ADHD (n=42) and control (n=21) children aged 10-13 years.
Main Results:
- ADHD subjects showed elevated coherence in the lower alpha (8 Hz) band and reduced coherence in the upper alpha (10-11 Hz) band.
- Visual stimulation led to reduced evoked potential power and increased frontal coherence in the ADHD group.
- Differences in upper alpha band coherence correlated with ADHD medication status in controls.
Conclusions:
- ADHD is associated with a static state of deficient functional brain connectivity.
- A stimulus-induced state of overconnectivity within and between frontal hemispheres was observed in ADHD.
- Findings highlight distinct connectivity profiles in ADHD, potentially influenced by external stimuli and medication.
Abstract:
Abnormal functional brain connectivity is a candidate factor in developmental brain disorders associated with cognitive dysfunction. We analyzed a substantial (10 min per subject) record of dense array electroencephalography with spectral power and coherence methods in attention-deficit hyperactivity disorder (ADHD) (n = 42) and control (n = 21) 10- to 13-year-old children. We found topographically distinct narrow band coherence differences between subject groups: ADHD subjects showed elevated coherence in the lower alpha (8 Hz) band and reduced coherence in the upper alpha (10-11 Hz) band. The 8-Hz ADHD elevation and a 2- to 6-Hz control group coherence elevation were independent of stimulus presentation. In response to visual stimulation, the ADHD group exhibited reduced evoked potential power and elevated frontal coherence. Only the upper alpha band control group coherence elevation discriminated according to ADHD group medication status. The findings suggest a static state of deficient connectivity in ADHD and a stimulus-induced state of overconnectivity within and between frontal hemispheres.
