The Behavioural and Neurophysiological Effects of Set-for-Variability (SfV) Reading Intervention for Children With Sustained Word Reading Difficulties.

This study investigates whether a Set-for-Variability (SfV) reading intervention improves irregular word reading and induces neural changes in the N400, specifically earlier onset latency and increased negative amplitude in incongruent conditions, among children with persistent word reading difficulties (RD). A pre-registered randomised control trial (RCT) was conducted with 30 children (average age: 9 years). Over 10 weeks, participants completed a 15-h online reading program. The SfV group focused on phoneme variation in decoding both regular and exception words, while the Current Best Practices (CBP) group received synthetic phonics and sight word instruction. Pre- and post-test reading ability and N400 event-related potentials (ERPs) were collected. Post-test results revealed that the SfV group achieved greater gains than the CBP group in irregular word reading, oral SfV, and increased N400 amplitude in the incongruent condition, indicating improved lexical-semantic processing. These behavioural and neural gains suggest that the SfV intervention improved children's ability to resolve print-sound inconsistencies and supported more efficient lexical access.