Investigating the Relationship between Theta/Beta Ratio and Intensity of Disease in Children with ADHD

Attention/Deficit-Hyperactivity Disorder (ADHD) is a neurodevelopmental disease in which the affected child experiences evidently lowered ability to concentrate and control impulses in comparison to natural state. Electroencephalography (EEG) based Biomarkers including measurement of the brain’s theta/beta waves ratio in the vertex(Cz) region can be useful to achieve diagnostic and therapeutic objectives as a noninvasive method and as such EEG biomarkers have been under extensive use in ADHD research, though they have not been clinically confirmed so far. This study attempted to examine the relationship between theta/beta ration with disease intensity in ADHD children as well as sensitivity and theta/beta ratio characteristic to detect AHDD and healthy children and the accuracy of this ratio to differentiate diseased children from healthy ones in terms of ADHD. This study is a case-control test, in which the statistical population consisted of 59 five-to-ten-year-old healthy children and 61 children with ADHD who had been chosen through simple random sampling, out of children visiting pediatric and adolescent psychiatric clinic in Zareh Hospital, Sari, Iran. All patients were examined in terms of disease intensity using parental Conner’s questionnaire. The theta/beta ratio in Cz and Fz points was tested and recorded individually each once during waking hours with open eyes with no mental task, and another time during a specific mental task by neurofeedback. beta, theta, and theta/beta without test was larger in the Fz region in the patient group than in the control group (p<0.001). There was a medium relationship between theta/beta (r=0.48; p<0.001) in Fz region and Conner’s score. Theta/beta without test in Fz ( p=0.02; sensitivity=62%; specificity=71%) and in Cz (p=0.03; sensitivity=51%; specificity=73%) differentiate the two groups only at a medium level. It seems that further research should be conducted using more precise tools like QEEG with a larger sample volume and more limited age group.