Steady-State Visual-Evoked EEG Dataset for Visual Function Assessment via Biomarker Extraction

S2VEEG (Steady-State Visual-Evoked EEG Dataset) is a 64-channel pediatric EEG dataset collected at Zhongshan Ophthalmic Center, Guangzhou, China, between March 2022 and October 2024 for visual function assessment and biomarker research, including 104 participants (30 healthy controls, 60 patients with amblyopia, and 14 patients with intermittent exotropia), with longitudinal follow-up data acquired after a 30-day home-based monocular perceptual learning treatment for treatment-responsive amblyopia cases and 2 months after strabismus surgery for intermittent exotropia cases; the full experimental protocol comprised resting-state EEG, transient visual evoked potentials, and steady-state visual evoked potentials, while the published Figshare resource specifically provides raw SSVEP EEG recordings in .bdf format, extracted small-worldness feature files in .npy format, participant metadata, and electrode position information, with EEG recorded using a 64-channel BioSemi ActiveTwo system under standardized visual stimulation conditions and preprocessed using common average re-referencing, 0.3–50 Hz bandpass filtering, downsampling to 200 Hz, and ICA-based artifact removal, making the dataset suitable for studies of electrophysiological alterations in pediatric visual disorders, treatment-related neuroplasticity, functional connectivity, biomarker discovery, and machine learning analysis.