Pre- and Postovulatory Auditory Brainstem Response in Normal Women

Abstract

Studies with ovarian hormones on auditory brainstem response (ABR) have conflicting reports although women have ABR shorter than men. This study compared ABR between pre-and postovulatory phases of menstrual cycle in consenting 40 healthy female volunteers (age 19 ± 2.35 years). The study was conducted under standard laboratory conditions (room temperature 26 ± 2°C) using Neuropack (Nihon Kohden machine, NM-420S; H636, Japan) and earphone dynamic receiver ELEGA (Type DR-531; no.237, Japan) in sound proof room. Ears were stimulated simultaneously using standard protocol. ABR was recorded in pre-and postovulatory phases. Ovulation was estimated by measuring basal body temperature. The ABR wave latencies (WLs) I, II, III, IV, V and inter-peak latencies (IPLs) I-III, III-V, I-V were compared between the two phases of menstrual cycle using paired t test. The postovulatory phase had shorter WL V (5.71 ± 0.18 ms vs. 5.81 ± 0.19 ms, p \ 0.01), IPL III-V (1.89 ± 0.16 ms vs. 1.94 ± 0.19 ms, p \ 0.05), and I-V (3.88 ± 0.16 ms vs. 3.95 ± 0.18 ms, p \ 0.05) than in preovulatory. Other WLs and IPLs showed decreasing trend in postovulatory phase. ABR is better in postovulatory phase as compared to preovulatory phase probably due to progesterone hormone which might be involved in modulating auditory hearing pathway at postovulatory phase.

Central conduction time in auditory brainstem response and ear advantage in dichotic listening across menstrual cycle

“…The participants were instructed to record the beginning of each menstrual cycle and the basal body temperature daily. The basal body temperature was used to verify ovulation for each participant [ 9 ]. Based on the data in the menstruation program, all participants had a regular, natural menstrual cycle of length 26 to 31 days.…”

“…The conflicting results in the effects of the menstrual cycle on the central conduction time in ABR and the ear advantage in dichotic listening may be due to the differences in research designs. For example, the data in ABR can be obtained with each ear tested separately [ 5 ] or with both ears stimulated simultaneously [ 9 ]. In dichotic listening, using real words as stimuli probably requires more working memory to process than using nonsense syllables [ 12 ].…”

Comparison of Cognitive Functions Between Male and Female Medical Students: A Pilot Study

“…Their cognitive functions were assessed during the preovulatory and postovulatory phases of the cycle. Preovulatory phase cognitive function was tested 2-4 days prior to the expected day of the ovulation and postovulatory cognitive function was tested between 9-11 days after ovulation, according to their menstrual cycles [9]. Ovulation was estimated by measuring BBT.…”

Association Between Sex and Speech Auditory Brainstem Responses in Adults, and Relationship to Sex Hormone Levels

“…In addition, many authors have focused on the effect of hormones on ABRs. Ovarian hormones have been reported to affect click ABRs [ 19 ]. Sex differences in speech ability have been also suggested to be related to reproductive hormones [ 5 ].…”