Introduction

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Frequency-Following Responses of Voice Pitch: A Comparison of Familiar vs. Stranger’s Voices in Normal-Hearing Adults Ashley Groeber, Fuh-Cherng JengSchool of Rehabilitation and Communication Sciences, Ohio University, Athens, Ohio, USA Introduction • PROCEDURES • Participants were seated and reclined comfortably in an acoustically and electrically treated sound proof booth. • EEG recorded from three gold-plated surface electrodes that were placed on the scalp • Recording montage: Fpz (non-inverting), M2 (inverting), and Low forehead (ground) • Impedance maintained below 3 kΩ at 10 Hz • Stimuli presented monaurally to the right ear via an ER-2A insert earphone with a silent interval of 45ms • 4000 sweeps • DATA ANALYSIS • Offline analysis completed in MatLab, SigmaPlot, and SPSS • Four Objective Measures: • Tracking Accuracy: Reflects accurateness of pitch encoding in the brainstem • Slope Error: Indicates how well the brain follows the overall shape of the pitch contour • Frequency Error: Represents the accuracy of pitch tracking • Pitch Strength: Reflects robustness of the response • A one-way ANOVA was conducted to determine significance between the five experimental conditions. A p value of <0.05 was considered statistically significant. Conclusions and Discussion Detecting the subtle differences in pitch serves an important role in the identification of familiar voices. The ability to identify familiar voices is important for speaker identification in everyday interactions. When this system is compromised, it can cause problems with your ability to communicate with others. For example, when answering the phone the listener relies on voice pitch to distinguish the caller’s identity. Previous electrophysiological studies of the cortical area have investigated the involvement of the cortex when processing familiar and unfamiliar voices. These studies have shown familiar voices have significantly more robust responses when compared to unfamiliar voices. In a study of brain activity (Tanaka & Kudo, 2012), nine adult women of good health were found to have a significant increase in cerebral functioning when listening to the familiar voice of the participant’s mother vs. a stranger’s voice. In Turnure’s study (1971), it was shown that the infants displayed greater interest in their mother’s voice than the unfamiliar stranger’s. Most studies have linked areas of the cortex to the identification of familiar vs. unfamiliar voices, but few studies have investigated the brainstem’s contribution. The current study will use frequency-following responses (FFR) to investigate the contribution of the brainstem to the listener’s ability to perceive differences in voice pitch between familiar and unfamiliar voices. Previous research has shown FFR in normal hearing adults and infants to accurately preserve the phase-locked neural activity of pitch information from steady-state and time-variant speech sounds and complex sounds (Krishnan et al., 2004; Jeng et al., 2011). Through the use of FFR, this study aims to examine and compare the responses of the listener to a familiar voice sample of the listener’s own voice or the listener’s mother’s voice and an unfamiliar voice sample of a stranger’s voice. Based on previous data, it was hypothesized that the familiar voice sample will elicit a stronger FFR than that of a stranger’s voice. • This study demonstrated: • The responses to a familiar voice sample of the listener’s own voice or the listener’s mother’s voice and an unfamiliar voice sample of a stranger’s voice. • There were no significant differences revealed in any of the measures, tracking accuracy, slope error, frequency error, or pitch strength, between FFRs of familiar voices and stranger voices (Figure 2, 3). • Only 3 responses to mother’s voices were obtained and examined. Further investigation is needed to determine whether a mother’s voice produces a stronger response than the listener’s own voice. References • Beauchemin, M., De Beaumont, L., Vannasing, P., Turcotte, A., Arcand, C., Belin, P., & Lassonde, M. (2006). Electrophysiological markers of voice familiarity. European Journal Of Neuroscience, 23(11), 3081-3086. doi:10.1111/j.1460-9568.2006.04856.x • Beauchemin, M., Gonzalez-Frankenberger, B., Tremblay, J., Vannasing, P., Martinez-Montes, E., Belin, P., Beland, R., Francoeur, D., Carceller, A., Wallois, F., & Lassonde, M. (2010). Mother and Stranger: An Electrophysiological Study of Voice Processing in Newborns. Cerebral Cortex, 21(8), 1705-1711. • Van Dommelen, W. A. (1990). ACOUSTIC PARAMETERS IN HUMAN SPEAKER RECOGNITION. Language & Speech, 33(3), 259-272. • Jeng, F., Costilow, C. E., Stangherlin, D. P., & Chia-Der, l. (2011). Relative Power of Harmonics in Human Frequency Following Responses Associated with Voice Pitch in American and Chinese Adults. Perceptual & Motor Skills, 113(1), 67-86. • Jeng, F., Hu, J., Dickman, B., Montgomery-Reagan, K., Tong, M., Wu, G., & Lin, C. (2011). Cross-Linguistic Comparison of Frequency-Following Responses to Voice Pitch in American and Chinese Neonates and Adults. Ear and Hearing, 32(6), 699-707. • Krishnan, A., Xu, Y., Gandour, J. T., & Cariani, P. A. (2004). Human frequency-following response: representation of pitch contours in Chinese tones. Hearing Research, 1891-12. doi:10.1016/S0378-5955(03)00402-7 • Marsh, J.T., Brown, W.S., Smith, J.C. (1974). Differential brainstem pathways for the conduction of auditory frequency following responses. Electroencephalogr. Clin.Neurophysiol. 38, 415-422. • Sohmer, H., Pratt, H., & Kinarti, R. (1977). Sources of frequency following responses (FFR) in man. Electroencephalography And Clinical Neurophysiology, 42(5), 656-664. • Tanaka, Y., & Kudo, Y. (2012). Effects of familiar voices on brain activity. International Journal Of Nursing Practice, 1838-44. • Turnure, C. (1971). Response to voice of mother and stranger by babies in the first year. Developmental Psychology, 4(2), 182-190. doi:10.1037/h0030431 • Van Lancker, D., & Canter, G. (1982). Impairment of voice and face recognition in patients with hemispheric damage. Brain And Cognition, 1(2), 185-195. Results Fig. 1 (Left) The time waveform and spectrogram of the FFR to each testing condition for one participant. • Fig. 2 (Above) Group comparisons plotted to quantify the listener’s ability to perceive differences in voice pitch between familiar and unfamiliar voices using four objective indices: Tracking Accuracy (top left), Slope Error(top right), Frequency Error (bottom left), and Pitch Strength (bottom right). No significant difference was seen between groups for all objective measures. Fig. 3 (Below) A post hoc Tukey test showed only the control group was significantly different from the other test conditions. No other voice conditions were significantly different. Methods • PARTICIPANTS • Twelve female native speakers of American English (mean age = 23.9 yr., SD = 2.54) • Normal hearing with thresholds ≤ 20 dB HL at 250-8000 Hz • STIMULUS • Four conditions and one optional condition were presented to each participant • The participant’s own voice • Two strangers’ voices • The participant’s mother’s voice (optional) • Control • Voice samples of the vowel /i/ with a rising pitch • Stimuli used for the two Stranger voices came from within the participant pool. • Participant A and B’s own voice would be the stranger voice for participants C and D. Participant A and B would not know participants C and D, etc. Tukey HSD Contact information