Schedule of Events | Symposia

Reduced habituation to tones in FXS compared to TD and ASD

Poster Session F - Tuesday, April 1, 2025, 8:00 – 10:00 am EDT, Back Bay Ballroom/Republic Ballroom

Winko An¹ (anwenkang@gmail.com), Michael Khela¹, Meagan Tsou¹, Carol Wilkinson¹; ¹Division of Developmental Medicine, Boston Children's Hospital

Background: Fragile X syndrome (FXS) is a rare genetic disorder often associated with autism spectrum disorder (ASD) and intellectual disability. Prior studies in FMR1 KO mice and adults with FXS report reduced neural habituation to repeated sounds, yet little is known about habituation in children with FXS compared to those with idiopathic ASD or Down syndrome (DS). Objectives: To characterize neural habituation to repeated tones in children with typical development (TD), ASD, FXS, and DS. Methods: Using an auditory paradigm, we presented pure tones (1000 Hz) in trials of three repeated tones, each separated by 500 ms, to 20 children with FXS (27–78 months, 3 females), 28 with ASD (32–83 months, 1 female), 26 with DS (24–68 months, 11 females), and 46 TD children (23–76 months, 9 females). High-density EEG data (≥40 trials per condition) were analyzed to extract P2 (44–188 ms) and N2 (216–384 ms) components. Habituation was calculated as the amplitude difference between First and Third tones (P2: First – Third; N2: Third – First) and assessed via one-sample t-tests. Results: TD (p=0.009) and ASD (p<0.001) groups showed significant P2 habituation, unlike FXS (p=0.194) and DS (p=0.434). TD (p=0.022) and DS (p=0.012) also showed N2 habituation, absent in ASD and FXS. Conclusions: TD children habituate to tones in both P2 and N2 components. Children with FXS lack significant habituation, while those with ASD or DS exhibit partial habituation in one component.

Topic Area: PERCEPTION & ACTION: Audition