Language Asymmetry and Hormonal Fluctuations During The Menstrual Cycle

Objective: The aim of this study was to investigate hormone-asymmetry relationships during the menstrual cycle for both hemispheres using verbal dichotic listening task. Method: This study was conducted with thirty-two normally cycling women; all of them were native German speakers and right-handed with no use of hormonal medication in the previous 6 months. STCI-S18, a questionnaire to assess current mood, the Edinburgh Handedness Inventory, a background questionnaire to collect demographic information, the Symptom-Checklist 90-R and a verbal dichotic listening task were administered to all participants/completed by all participants. Result: Statistical analysis indicated that the main effect of ear was significant (p=.007). A right ear advantage was observed, but neither the main effect of cycle (p=.303) nor the interaction of ear and cycle (p=.955) was significant. We did find, however, a significant main effect of cycle on auditory recognition when we analyzed the data of the 17 participants with validated estradiol changes (p=.047). Conclusion: The results of the dichotic listening task data showed that the degree of language asymmetry as revealed by dichotic listening did not change during the three menstrual phases. We did find, however, that the main effect of cycle was significant when we analyzed the data of 17 participants with available estradiol levels. Estradiol seems to affect overall auditory recognition without altering asymmetry.