Electrophysiological and psychophysical testing in children with attention-deficit hyperactivity disorder

Background
Multiple techniques are used for understanding, determining the real pathophysiological process, and treating attention-deficit hyperactivity disorder (ADHD). The aim of this study was to assess cortical auditory evoked potentials (CAEP) as well as P300 in children with ADHD, and its correlation with neurocognitive tests [Wisconsin card sorting test (WCST), digit span (DS), and Stroop test (ST)].
Patients and methods
A prospective cross-sectional study was performed on 103 children, who were divided into two groups: 53 children newly diagnosed with ADHD (according to , 5th ed.), who were drug naïve, and 50 normal control matched for age, sex, educational and social level, and intelligence quotient. All participants had detailed psychiatric history, intelligence quotient Wechsler intelligence scale for children (WICS), Conners’ parent/teacher rating scale abbreviated form for ADHD, neuropsychological tests (WCST and Stroop), pure tone audiometry, speech audiometry using GSI 61 audiometer, immittance test using interacoustic, and sustained attention test using auditory continuous performance test (ACPT) P300.
Results
Children with ADHD had more perseverative responses, more preservative errors, and more failure to maintain set (FMS) than controls in WCST, with a significant difference among study groups. ADHD group was impaired in digit span backward and ST than control group. P300 amplitude and latency were significantly different between the study groups. In comparison with the control group, statistical delayed latencies of significance were observed in ADHD between all CAEP components. A significant difference for P1-N1 amplitude was observed among different components of CAEP, and no significance was observed regarding P2-N2 amplitude. ACPT showed a significant difference between both groups, with higher percentage in control group. Positive correlations were observed between P300 amplitude and WCST (perseverative error), P300 amplitude and ST results, and N2 latency and DS backward.
Conclusion
Assessment of CAEPs and P300 in children with ADHD, as well as their correlation with neurocognitive tests (WCST, DS, and ST), is crucial in diagnosis and management.