Speech across the menstrual cycle: a replication and extension study

Whiteside et al. [S.P. Whiteside, A. Hanson, P.E. Cowell, Hormones and temporal components of speech: sex differences and effects of menstrual cyclicity on speech, Neurosci. Lett. 367 (2004) 44-47] documented effects of menstrual cycle phase and sex on voice onset time (VOT) in naturally timed speech using whole words. VOT is a temporal component of speech that plays an important role in production and perception [L.L. Koenig, Laryngeal factors in voiceless consonant production in men, women, and 5-year-olds, J. Speech Lang. Hear. Res. 43 (2000) 1211-1228; A. Löfqvist, L.L. Koenig, R.S. McGowan, Vocal tract aerodynamics in /aCa/ utterances: measurements, Speech Commun. 16 (1995) 49-66; T.M. Nearey, B. Rochet, Effects of place of articulation and vowel context in VOT production and perception for French and English Stops, J. Int. Phon. Assoc. 24 (1994) 1-18; L.M. Rimol, T. Eichele, K. Hugdahl, The effect of voice-onset-time on dichotic listening with consonant-vowel syllables, Neuropsychologia 44 (2006) 191-196; P.G. Simos, R.L. Diehl, J.I. Breier, M.R. Molis, G. Zouridakis, A.C. Papanicolaou, MEG correlates of categorical perception of a voice onset time continuum in humans, Cogn. Brain Res. 7 (1998) 215-219; S.P. Whiteside, J. Marshall, Developmental trends in voice onset time: some evidence for sex differences, Phonetica 58 (2001) 196-210]. The present study was designed to replicate and expand upon Whiteside et al. [S.P. Whiteside, A. Hanson, P.E. Cowell, Hormones and temporal components of speech: sex differences and effects of menstrual cyclicity on speech, Neurosci. Lett. 367 (2004) 44-47] using a speeded syllable repetition paradigm. VOT measurements for 6 English plosives (/p b t d k g/) were obtained from speech samples of 15 women and 20 men (age 20-25 years). Women were tested across two points in the menstrual cycle (Days 2-5: low estrogen and progesterone/low-EP; Days 18-25: high estrogen and progesterone/high-EP) and men were tested once. Results indicated significant interaction between menstrual cycle phase and voicing (F(1,14)=8.239, P<0.02), whereby the voiced plosives (b, g) displayed shorter VOT values and the voiceless plosives (p, k) displayed longer values at the high-EP phase. Thus, the distinction between the voiced and voiceless plosive was enhanced at high-EP. Significant sex effects (F(1,33)=10.080, P<0.005) were seen with women at high-EP but not the low-EP phase having longer VOT values than men for voiceless plosives. Sex differences between the voiced and voiceless plosives were enhanced at the high-EP phase. This study indicates a role for activational ovarian hormones in regulating temporal features of speech in both whole words and speeded syllable repetition.