Verena G. Skuk

Gender differences in familiar voice identification

We investigated gender differences in the identification of personally familiar voices in a gender-balanced sample of 40 listeners. From various types of utterances, listeners had to identify by name 20 speakers (10 female) among a set of 70 possible classmates who were all 12th grade pupils from the same local secondary school. Mean identification rates were 67% from sentences, and around 35% for an isolated /Hello/ or a VCV syllable. Even from non-verbal harrumphs, speakers were identified with an accuracy of 18%, i.e. highly above chance levels. Substantial individual differences were observed between listeners. Importantly, superior overall performance of female listeners was qualified by an interaction between voice gender and listener gender. Male listeners exhibited an own-gender bias (i.e. better identification for male than female voices), whereas female listeners identified voices of both genders at similar levels. Individual own-gender identification biases were correlated with differences in reported contact to a speakers voice and voice distinctiveness. Overall, the present study establishes a number of factors that account for substantial individual differences in personal voice identification.

Speaker perception: Speaker perception

While humans use their voice mainly for communicating information about the world, paralinguistic cues in the voice signal convey rich dynamic information about a speakers arousal and emotional state, and extralinguistic cues reflect more stable speaker characteristics including identity, biological sex and social gender, socioeconomic or regional background, and age. Here we review the anatomical and physiological bases for individual differences in the human voice, before discussing how recent methodological progress in voice morphing and voice synthesis has promoted research on current theoretical issues, such as how voices are mentally represented in the human brain. Special attention is dedicated to the distinction between the recognition of familiar and unfamiliar speakers, in everyday situations or in the forensic context, and on the processes and representational changes that accompany the learning of new voices. We describe how specific impairments and individual differences in voice perception could relate to specific brain correlates. Finally, we consider that voices are produced by speakers who are often visible during communication, and review recent evidence that shows how speaker perception involves dynamic face-voice integration. The representation of para- and extralinguistic vocal information plays a major role in person perception and social communication, could be neuronally encoded in a prototype-referenced manner, and is subject to flexible adaptive recalibration as a result of specific perceptual experience. WIREs Cogn Sci 2014, 5:15-25. doi: 10.1002/wcs.1261 CONFLICT OF INTEREST: The authors have declared no conflicts of interest for this article. For further resources related to this article, please visit the WIREs website.

Adaptation aftereffects in vocal emotion perception elicited by expressive faces and voices.

The perception of emotions is often suggested to be multimodal in nature, and bimodal as compared to unimodal (auditory or visual) presentation of emotional stimuli can lead to superior emotion recognition. In previous studies, contrastive aftereffects in emotion perception caused by perceptual adaptation have been shown for faces and for auditory affective vocalization, when adaptors were of the same modality. By contrast, crossmodal aftereffects in the perception of emotional vocalizations have not been demonstrated yet. In three experiments we investigated the influence of emotional voice as well as dynamic facial video adaptors on the perception of emotion-ambiguous voices morphed on an angry-to-happy continuum. Contrastive aftereffects were found for unimodal (voice) adaptation conditions, in that test voices were perceived as happier after adaptation to angry voices, and vice versa. Bimodal (voice + dynamic face) adaptors tended to elicit larger contrastive aftereffects. Importantly, crossmodal (dynamic face) adaptors also elicited substantial aftereffects in male, but not in female participants. Our results (1) support the idea of contrastive processing of emotions (2), show for the first time crossmodal adaptation effects under certain conditions, consistent with the idea that emotion processing is multimodal in nature, and (3) suggest gender differences in the sensory integration of facial and vocal emotional stimuli.

Temporally variable multi-aspect N-way morphing based on interference-free speech representations

Voice morphing is a powerful tool for exploratory research and various applications. A temporally variable multi-aspect morphing is extended to enable morphing of arbitrarily many voices in a single step procedure. The proposed method is implemented based on interference-free representations of periodic signals and found to yield highly-naturally sounding manipulated voices which are useful for investigating human perception of voice. The formulation of the proposed method is general enough to be applicable to other representations and easily modified depending on application needs.

Perceiving vocal age and gender: An adaptation approach

Aftereffects of adaptation have revealed both independent and interactive coding of facial signals including identity and expression or gender and age. By contrast, interactive processing of non-linguistic features in voices has rarely been investigated. Here we studied bidirectional cross-categorical aftereffects of adaptation to vocal age and gender. Prolonged exposure to young (~20yrs) or old (~70yrs) male or female voices biased perception of subsequent test voices away from the adapting age (Exp. 1) and the adapting gender (Exp. 2). Relative to gender-congruent adaptor-test pairings, vocal age aftereffects (VAAEs) were reduced but remained significant when voice gender changed between adaptation and test. This suggests that the VAAE relies on both gender-specific and gender-independent age representations for male and female voices. By contrast, voice gender aftereffects (VGAEs) were not modulated by age-congruency of adaptor and test voices (Exp. 2). Instead, young voice adaptors generally induced larger VGAEs than old voice adaptors. This suggests that young voices are particularly efficient gender adaptors, likely reflecting more pronounced sexual dimorphism in these voices. In sum, our findings demonstrate how high-level processing of vocal age and gender is partially intertwined.

Role of timbre and fundamental frequency in voice gender adaptation

Prior adaptation to male (or female) voices causes androgynous voices to be perceived as more female (or male). Using a selective adaptation paradigm the authors investigate the relative impact of the vocal fold vibration rate (F0) and timbre (operationally in this paper as characteristics that differentiate two voices of the same F0 and loudness) on this basic voice gender aftereffect. TANDEM-STRAIGHT was used to morph between 10 pairs of male and female speakers uttering 2 different vowel-consonant-vowel sequences (20 continua). Adaptor stimuli had one parameter (either F0 or timbre) set at a clearly male or female level, while the other parameter was set at an androgynous level, as determined by an independent set of listeners. Compared to a control adaptation condition (in which both F0 and timbre were clearly male or female), aftereffects were clearly reduced in both F0 and timbre adaptation conditions. Critically, larger aftereffects were found after timbre adaptation (comprising androgynous F0) compared to F0 adaptation (comprising an androgynous timbre). Together these results suggest that timbre plays a larger role than F0 in voice gender adaptation. Finally, the authors found some evidence that individual differences among listeners reflect in part pre-experimental contact to male and female voices.

Electrophysiological correlates of voice memory for young and old speakers in young and old listeners

ABSTRACT Faces of ones own‐age group are easier to recognize than other‐age faces. Using behavioral measures and EEG, we studied whether an own‐age bias (OAB) also exists in voice memory. Young (19 ‐ 26 years) and old (60–75 years) participants studied young (18–25 years) and old (60–77 years) unfamiliar voices from short sentences. Subsequently, they classified studied and novel voices as “old” (i.e. studied) or “new”, from the same sentences. Recognition performance was higher in young compared to old participants, and for old compared to young voices, with no OAB. At the same time, we found evidence for higher distinctiveness of old compared to young voices, both in terms of acoustic measures and subjective ratings (independent of rater age). Analyses of event‐related brain potentials (ERPs) indicated more negative‐going deflections (400–1000 ms) for old compared to young voices in young participants. In old participants, we observed a reversed OLD/NEW memory effect, with overall more positive amplitudes for novel compared to studied old (but not young) voices (400–1000 ms). Time‐frequency analyses revealed less beta power (16–26 Hz) for young compared to old voices at left anterior sites, and also reduced beta power for correctly recognized studied (compared to novel) voices at left posterior sites (300–900 ms). These findings could suggest an engagement of cortical areas during stimulus‐specific recollection from about 300 ms, in a task that emphasized the analysis of individual acoustic features. HighlightsWe found better recognition of old vs. young voices in both old and young adults.These effects may relate to increased distinctiveness of old voices.We found no own‐age bias in voice recognition.Recognized vs. novel voices elicited suppressed EEG beta band power.These effects reflect stimulus‐specific voice recollection from about 300 ms.

Autistic Traits are Linked to Individual Differences in Familiar Voice Identification

Autistic traits vary across the general population, and are linked with face recognition ability. Here we investigated potential links between autistic traits and voice recognition ability for personally familiar voices in a group of 30 listeners (15 female, 16–19 years) from the same local school. Autistic traits (particularly those related to communication and social interaction) were negatively correlated with voice recognition, such that more autistic traits were associated with fewer familiar voices identified and less ability to discriminate familiar from unfamiliar voices. In addition, our results suggest enhanced accessibility of personal semantic information in women compared to men. Overall, this study establishes a detailed pattern of relationships between voice identification performance and autistic traits in the general population.