Electrophysiological and morphological alteration in the visual pathway of children with attention-deficit/hyperactivity disorder

Introduction Attention-deficit/hyperactivity disorder (ADHD) is one of the most common neurodevelopmental disorders in children. Optical Coherence Tomography (OCT) and Visual evoked potentials (VEP) are common non-invasive diagnostic techniques. Researchers can use these techniques to identify possible biomarkers and explore the neurodevelopmental mechanisms underlying ADHD. Methods The ADHD group (37 cases, average age 8.81 ± 1.44 years) and the healthy controls (38 cases, average age 8.97 ± 1.43 years), had the OCT and VEP. The retinal nerve fibre layer (RNFL), optic disc parameters, and macular parameters were measured through OCT. The latencies of P100 and the amplitudes of N75-P100 and P100-N135 waves at three different spatial frequencies (visual angles of 15’, 30’, and 60’) were tested through VEP. Results The average RNFL and RNFL in each quadrant between the two groups were no statistically significant (all p > 0.05). The optic disc area, average cup-to-disc ratio, and cup volume in the ADHD group were all significantly larger than those in the control group (all p < 0.05). At three visual angles (15’, 30’, 60’), P100-latency in the ADHD group were all more significant than those in the control group (all p < 0.05). The amplitudes of N75-P100 and P100-N135 in the ADHD group were all statistically significantly lower than those in the control group (all p ≤ 0.001). Discussion From the perspective of electroencephalophysiology, children with ADHD may have early visual information processing disorders. This provides a theoretical and practical basis for further early intervention in children with ADHD from the field of visual perception. The study protocol followed the tenets of the Declaration of Helsinki, was approved by the local ethics committee (No 2023-2240), and was registered on ClinicalTrials.gov (ChiCTR2400086223).