id_662. SEX DIFFERENCES IN LOW-GAMMA AUDITORY ENVELOPE FOLLOWING RESPONSES
Aurimas Mockevičius1,2, Inga Griškova-Bulanova1,2
1 Vilnius University, Medical Science Center, Translational Health Research Institute, Vilnius, Lithuania
2 Vilnius University, Life Sciences Center, Institute of Biosciences, Vilnius Lithuania
INTRODUCTION: Envelope-following responses (EFRs) provide a robust, noninvasive assessment of gamma-range cortical synchronization. While sex influences brain structure, auditory processing, and neuropsychiatric risk, sex-related variation in gamma-range auditory entrainment remains insufficiently characterized.
AIM(S): We aimed to test whether the ability to drive cortical networks in the low-gamma range differs between females and males using a click-based chirp-like auditory stimulus covering 30–60 Hz.
METHOD(S): Electroencephalography was recorded from 80 healthy young adults (42 females; mean age 26.07 years). To reduce hormonal-state variability, females were assessed during the early follicular phase. Time–frequency responses were quantified across nine fronto-central electrodes using phase-locking index (PLI) and event-related spectral perturbation (ERSP), and individual gamma frequency (IGF) was estimated as the frequency eliciting maximal synchronization or power.
RESULTS: Males exhibited significantly stronger responses than females, with higher PLI in the 35–43 Hz range and higher ERSP in the 35–46 Hz range (Bonferroni-corrected p < 0.05). In contrast, IGFs did not differ between sexes and no hemispheric lateralization effects were observed.
CONCLUSIONS: These findings demonstrate sex-related differences in low-gamma auditory EFR strength but not in resonance frequency, underscoring the need for sex-specific normative baselines in clinical and translational applications of gamma-range auditory paradigms.
FINANCIAL SUPPORT: This study was supported by the Research Council of Lithuania (LMTLT agreement no. S-LJB-20-1).