Electroencephalogram complexity analysis in children with attention-deficit/hyperactivity disorder during a visual
Hadi Zarafshan1, Ali Khaleghi1,2, Mohammad Reza Mohammadi1
1a Psychiatry & Psychology Research Center , Tehran University of Medical Sciences , Tehran , Iran.
Insights
Children with attention-deficit/hyperactivity disorder (ADHD) exhibit altered brain activity complexity during cognitive tasks. This study found higher Lempel-Ziv complexity (LZC) in the right hemisphere of ADHD brains, suggesting potential posterior region and cerebellum involvement.
Area of Science:
- Neuroscience
- Child Psychology
- Biomedical Engineering
Background:
- Attention-deficit/hyperactivity disorder (ADHD) is a common neurodevelopmental disorder.
- Current understanding of ADHD pathophysiology often focuses on fronto-striatal dysfunction.
- Investigating brain activity dynamics through complexity analysis offers novel insights.
Purpose of the Study:
- To compare electroencephalogram (EEG) complexity using Lempel-Ziv complexity (LZC) between children with ADHD and healthy controls during a cognitive task.
- To identify differences in brain activity patterns associated with ADHD during cognitive load.
Main Methods:
- Thirty children diagnosed with ADHD (ages 7-12) and 30 healthy controls participated.
- EEG data were collected during a cognitive task.
- Lempel-Ziv complexity (LZC) was computed to analyze EEG signal complexity.
Main Results:
- Children with ADHD showed significantly higher LZC in right anterior and posterior brain regions compared to controls.
- The ADHD group exhibited greater complexity in the right hemisphere versus the left.
- Healthy controls displayed higher complexity in the left hemisphere compared to the right.
Conclusions:
- Findings suggest altered brain complexity in posterior regions and potentially the cerebellum in children with ADHD.
- The results challenge a sole focus on fronto-striatal dysfunction, highlighting broader neural network involvement.
- EEG complexity analysis provides a valuable tool for understanding ADHD neurobiology.
Objective:
The aim of this study was to investigate electroencephalogram (EEG) dynamics using complexity analysis in children with attention-deficit/hyperactivity disorder (ADHD) compared with healthy control children when performing a cognitive task.
Method:
Thirty 7-12-year-old children meeting Diagnostic and Statistical Manual of Mental Disorders-Fifth Edition (DSM-5) criteria for ADHD and 30 healthy control children underwent an EEG evaluation during a cognitive task, and Lempel-Ziv complexity (LZC) values were computed. There were no significant differences between ADHD and control groups on age and gender.
Results:
The mean LZC of the ADHD children was significantly larger than healthy children over the right anterior and right posterior regions during the cognitive performance. In the ADHD group, complexity of the right hemisphere was higher than that of the left hemisphere, but the complexity of the left hemisphere was higher than that of the right hemisphere in the normal group.
Conclusion:
Although fronto-striatal dysfunction is considered conclusive evidence for the pathophysiology of ADHD, our arithmetic mental task has provided evidence of structural and functional changes in the posterior regions and probably cerebellum in ADHD.
