Contextual Musicality: vocal modulation and its perception in human social interaction

Music and language are both deeply rooted in our biology, but scientists have given far more attention to the neurological, biological and evolutionary roots of language than those of music. Because of this, and probably partially due to this, the purpose of music, in evolutionary terms, remains a mystery. Our brain, physiology and psychology make us capable of producing and listening to music since early infancy; therefore, our biology and behaviour are carrying some of the clues that need to be revealed to understand what music is “for”. Furthermore, music and language have a deep relationship, particularly in terms of cognitive processing, that can provide clues about the origins of music. Non-verbal behaviours, including voice characteristics during speech, are an important form of communication that enables individual recognition and assessment of the speaker’s physical characteristics (including sex, femininity/masculinity, body size, physical strength, and attractiveness). Vocal parameters, however, can be intentionally varied, for example altering the intensity (loudness), rhythm and pitch during speech. This is classically demonstrated in infant directed speech (IDS), in which adults alter vocal characteristics such as pitch, cadence and intonation contours when speaking to infants. In this thesis, I analyse vocal modulation and its perception in human social interaction, in different social contexts such as courtship and authority ranking relationships. Results show that specific vocal modulations, akin to those of IDS, and perhaps music, play a role in communicating courtship intent. Based on these results, as well the body of current knowledge, I then propose a model for the evolution of musicality, the human capacity to process musical information, in relation to human vocal communication. I suggest that musicality may not be limited to specifically musical contexts, and can have a role in other domains such as language, which would provide further support for a common origin of language and music. This model supports the hypothesis of a stage in human evolution in which individuals communicated using a music-like protolanguage, a hypothesis first suggested by Darwin

Want to know if your partner’s cheating on you? Just listen to their voice

First paragraph: Picture Morgan Freeman, Donald Trump or Margaret Thatcher. Most likely you can hear their voices in your mind, and the characteristic inflections that they put on certain words, as well as their tone and pitch. Even without listening to the words, when you hear someone speak you can pick up important information about them from characteristics such as how loud or deep their voice is. At the most basic level, voices convey biological characteristics such as whether someone is male or female, their body size and physical strength, age and sexual maturity. For example, Donald Trump’s voice can signal to you that he is a man, and that he has passed middle age. But did you know that voices can also signal a person’s attractiveness, fertility and even the likelihood of them being unfaithful

Digit ratio (2D:4D) predicts facial, but not voice or body odour, attractiveness in men

There is growing evidence that human second-to-fourth digit ratio (or 2D:4D) is related to facial features involved in attractiveness, mediated by in utero hormonal effects. The present study extends the investigation to other phenotypic, hormone-related determinants of human attractiveness: voice and body odour. Pictures of faces with a neutral expression, recordings of voices pronouncing vowels and axillary odour samples captured on cotton pads worn for 24 h were provided by 49 adult male donors. These stimuli were rated on attractiveness and masculinity scales by two groups of 49 and 35 females, approximately half of these in each sample using hormonal contraception. Multivariate regression analyses showed that males' lower (more masculine) right 2D:4D and lower right-minus-left 2D:4D (Dr2l) were associated with a more attractive (and in some cases more symmetrical), but not more masculine, face. However, 2D:4D and Dr2l did not predict voice and body odour masculinity or attractiveness. The results were interpreted in terms of differential effects of prenatal and circulating testosterone, male facial shape being supposedly more dependent on foetal levels (reflected by 2D:4D ratio), whereas body odour and vocal characteristics could be more dependent on variation in adult circulating testosterone levels

Perceived differences in social status between speaker and listener affect the speaker's vocal characteristics

Non-verbal behaviours, including voice characteristics during speech, are an important way to communicate social status. Research suggests that individuals can obtain high social status through dominance (using force and intimidation) or through prestige (by being knowledgeable and skilful). However, little is known regarding differences in the vocal behaviour of men and women in response to dominant and prestigious individuals. Here, we tested within-subject differences in vocal parameters of interviewees during simulated job interviews with dominant, prestigious, and neutral employers (targets), while responding to questions which were classified as introductory, personal, and interpersonal. We found that vocal modulations were apparent between responses to the neutral and high-status targets, with participants, especially those who perceived themselves as low in dominance, increasing fundamental frequency (F0) in response to the dominant and prestigious targets relative to the neutral target. Self-perceived prestige, however, was less related to contextual vocal modulations than self-perceived dominance. Finally, we found that differences in the context of the interview questions participants were asked to respond to (introductory, personal, interpersonal), also affected their vocal parameters, being more prominent in responses to personal and interpersonal questions. Overall, our results suggest that people adjust their vocal parameters according to the perceived social status of the listener as well as their own self-perceived social status

Self-reported dominance in women: Associations with hormonal contraceptive use, relationship status, and testosterone

How to achieve dominance in a group is a recurrent challenge for individuals of many species, including humans. Previous research indicates that both relationship status and contraceptive use appear to moderate women’s testosterone levels. If testosterone contributes to dominance, this raises the possibility for group differences in dominance between single and partnered women, and between users and non-users of hormonal contraception. Here, we examine associations between relationship status and use/non-use of hormonal contraception and women’s self-reported social dominance. In a sample of 84 women, we replicate previous research documenting a significant positive correlation between women’s saliva testosterone levels and their self-reported dominance. Consistent with other literature, we also find that women using hormonal contraception have significantly lower testosterone than those who are regularly cycling and that partnered women have significantly lower testosterone than single women. Although we do not find a main effect of either relationship status or hormonal contraceptive use status on women’s reported levels of dominance, the interaction between these variables predicted reported dominance scores. This interaction remained significant when participant age and testosterone values were added to the model as covariates. We discuss these results in the context of the existing literature on testosterone and women’s dominance behaviour and with respect to the evolutionary benefits of social dominance in women

Vocal modulation during courtship increases proceptivity even in naive listeners

Speakers modulate their voice when talking to infants, but we know little about subtle variation in acoustic parameters during speech in adult social interactions. Because tests of perception of such variation are hampered by listeners' understanding of semantic content, studies often confine speech to enunciation of standard sentences, restricting ecological validity. Furthermore, apparent paralinguistic modulation in one language may be underpinned by specific parameters of that language. Here we circumvent these problems by recording speech directed to attractive or unattractive potential partners or competitors, and testing responses to these recordings by naive listeners, across both a Germanic (English) and a Slavic (Czech) language. Analysis of acoustic parameters indicates that men's voices varied F0 most in speech towards potential attractive versus unattractive mates, while modulation of women's F0 variability was more sensitive to competitors, with higher variability when those competitors were relatively attractive. There was striking similarity in patterns of social context-dependent F0 variation across the two model languages, with both men's and women's voices varying most when responding to attractive individuals. Men's minimum pitch was lower when responding to attractive than unattractive women. For vocal modulation to be effective, however, it must be sufficiently detectable to promote proceptivity towards the speaker. We showed that speech directed towards attractive individuals was preferred by naive listeners of either language over speech by the same speaker to unattractive individuals, even when voices were stripped of several acoustic properties by low-pass filtering, which renders speech unintelligible. Our results suggest that modulating F0 may be a critical parameter in human courtship, independently of semantic content

The price of prosociality in pandemic times

The SARS-CoV-2 pandemic has imposed widespread negative impacts (economically, psychologically, neurologically, and societally), and has changed daily behaviors on a global scale. Such impacts are more significant and pervasive in countries with higher levels of inequality and reduced Government capacity and responsiveness, such as those in the Global South (e.g., Colombia). Differences in social and moral cognitive skills may significantly impact individual attitudes and responses to the pandemic. Here, we aimed to assess the extent to which factors associated with prosociality (including empathy, theory of mind (ToM), and moral judgments) predict the perception of SARS-CoV-2 impacts and responses. Participants (N=413) from Colombia answered factors associated with prosociality measures and judgments about SARS-CoV-2 risk, impact, and acceptance of quarantine guidelines. Results revealed that affective empathy (personal distress and empathic concern) and moral tendencies (deontological trends) predicted greater acceptance of quarantine but in turn yielded an increased perception of risks and individual impacts of SARS-CoV-2. Moreover, age (older) and gender (female) also increased the risk perception and impact estimation. These results underscore the role of prosocial-related predispositions informing individual responses to the pandemic and provide an opportunity to exploit this knowledge to inform successful interventions favoring behavioral change