Vocal communication across cultures: theoretical and methodological issues

The relationship between auditory perception and vocal production has been typically investigated by evaluating the effect of either altered or degraded auditory feedback on speech production in either normal hearing or hearing-impaired individuals. Our goal in the present study was to examine this relationship in individuals with superior auditory abilities. Thirteen professional musicians and thirteen nonmusicians, with no vocal or singing training, participated in this study. For vocal production accuracy, subjects were presented with three tones. They were asked to reproduce the pitch using the vowel /a/. This procedure was repeated three times. The fundamental frequency of each production was measured using an autocorrelation pitch detection algorithm designed for this study. The musicians' superior auditory abilities (compared to the nonmusicians) were established in a frequency discrimination task reported elsewhere. Results indicate that (a) musicians had better vocal production accuracy than nonmusicians (production errors of 1/2 a semitone compared to 1.3 semitones, respectively); (b) frequency discrimination thresholds explain 43% of the variance of the production data, and (c) all subjects with superior frequency discrimination thresholds showed accurate vocal production; the reverse relationship, however, does not hold true. In this study we provide empirical evidence to the importance of auditory feedback on vocal production in listeners with superior auditory skills.

Vocal affect is a subcomponent of emotion programs that coordinate a variety of physiological and psychological systems. Emotional vocalizations comprise a suite of vocal behaviors shaped by evolution to solve adaptive social communication problems. The acoustic forms of vocal emotions are often explicable with reference to the communicative functions they serve. An adaptationist approach to vocal emotions requires that we distinguish between evolved signals and byproduct cues, and understand vocal affect as a collection of multiple strategic communicative systems subject to the evolutionary dynamics described by signaling theory. We should expect variability across disparate societies in vocal emotion according to culturally evolved pragmatic rules, and universals in vocal production and perception to the extent that form–function relationships are present.

Studying Ethnic Minority and Economically Disadvantaged Populations: Methodological Challenges and Best Practices. George P. Knight, Mark W. Roosa, & Adriana J. Umana-Taylor. Washington, DC: American Psychological Association. 2009. 224 pp. ISBN 1433804743. $69.95 cloth. Studying Ethnic Minority' and Economically Disadvantaged Populations is a guide for researchers who seek to study people of color and the poor. The authors note that the need for such a volume is evident in the proliferation of flawed research on specific ethnic and economic groups. To address this need, George P. Knight, Mark W. Roosa, and Adriana J. Umana-Taylor have written a slim and easy-to-read book with chapters on sampling, ethics, measurement equivalence, translation, and prevention. In selecting the methodological topics covered in the book, the authors have identified the most challenging aspects of such research and have compiled a primer on possible solutions to many challenges. Students who are beginning to conduct independent research will benefit from the book. Chapters begin with basic methodological principles, then include a discussion of the misapplications of those principles in studies of various ethnic groups and the poor, and then make recommendations for applying the principles with those populations. All the chapters emphasize the importance of critically evaluating cross-cultural research, which will likely lead to meaningful conversations about methodological issues and about how to think critically about published research if students and advisers read this book together. Therefore, it is a good book for introducing new researchers to the methodological issues of cross-cultural research. I found the authors' emphasis on measurement equivalence (Chapter 4) to be especially important because the transfer of psychometric properties across cultures and languages is often an overlooked facet of assessment. This is a good chapter for introducing students and experienced researchers to the issues of working with translated measures and interviews. The authors compare two statistical methods for evaluating measurement equivalence and recommend one procedure over the other. Readers who want more specifics about the procedures, which would be anyone who will actually run these analyses, can read of the authors' published work to see how they applied them to their own data (e.g., Nair, White, Knight, & Roosa, 2009). As such, the discussion of measurement equivalence is especially valuable because of the lack of attention the issue has received in much of the empirical literature on ethnic minorities and the poor. Although the book has much to offer students and beginning researchers, there were aspects that dampened my enthusiasm for it as a guide for more seasoned researchers. First, in addition to material that introduces the methodological issues in researching these populations, there are sections that assume that the researcher has either a high level of expertise or access to vast resources. Yet there seemed to be little attempt to connect the introductory sections with the advanced sections, which might lead to frustration among readers. For example, the chapter on measurement equivalence, which I still recommend, was both too basic and too advanced to be truly instructive. The first part of the chapter is a review of basic principles of psychometric theory, which should be familiar to most quantitative researchers. The second part is a sophisticated discussion of the benefits of nested hierarchical models in confirmatory factor analysis (CFA). There is little segue from the introductory material to the CFA material. There are similar issues in other chapters. A second major concern is that the authors have a tendency to rely too heavily on vague sources, as indicated in their use of phrases like some researchers feel . (p. 5) without citations to any specific researchers who feel that particular way. …

Bird Speech Perception and Vocal Production: A Comparison with Humans

Language and communication are the bedrock of qualitative enquiry. Language is a fundamental tool through which qualitative researchers seek to understand human behaviour, social processes and the cultural meanings that inscribe human behaviour. However, when conducting cross-cultural research, issues of language and communication become more complex and often require the assistance of interpreters/translators as “cultural brokers”. Cross-cultural research poses numerous methodological, epistemological and practical challenges, which are rarely debated in qualitative research. This chapter outlines the epistemological approach to language and communication in different research paradigms and demonstrates the implications of this for the rigour of qualitative enquiry. In particular, concepts of transparency, subjectivity and reflexivity, which are indicators of methodological rigour in qualitative research, are typically not applied to language assistants in cross-cultural qualitative research despite the critical role of language assistants in the generation of knowledge and its cultural interpretation. Improving cross-cultural qualitative research involves understanding how language and communication can affect rigour and addressing language and communication issues that underlie the entire research process. Failure to recognise and acknowledge the role of language and communication issues in cross-cultural research may impact on the rigour and reliability of the research.

Spontaneous vocal differentiation of coo-calls for tools and food in Japanese monkeys

Vocal communication plays an important role in the lives of both humans and many animal species. Ensuring accurate communication, however, requires auditory self-monitoring to control vocal production and rapidly compensate for errors in vocal output. Despite the importance of this process, the underlying neural mechanisms are relatively unknown. Previous work has demonstrated that neurons in the auditory cortex are suppressed during vocal production, while simultaneously maintaining their sensitivity to vocal feedback, suggesting a role in auditory self-monitoring. The behavioral role of auditory cortex in vocal control, however, remains unclear. We investigated the function of auditory cortical activity during vocal self-monitoring and feedback-dependant vocal control in marmoset monkeys. Using real-time frequency-shifted feedback during vocalization, we demonstrate that marmosets exhibit rapid compensatory changes in vocal production, a feedback-dependent behavior that is predicted by the activities of neurons in auditory cortex. We further establish the role of auditory cortex in vocal control using electrical microstimulation to evoke rapid changes in produced vocalizations. These findings suggest a causal role for the auditory cortex in vocal self-monitoring and feedback-dependent vocal control, linking mechanisms of production and perception, and have important implications for understanding human speech motor control.

Vocal communication involves both speaking and hearing, often taking place concurrently. Vocal production, including human speech and animal vocalization, poses a number of unique challenges for the auditory system. It is important for the auditory system to monitor external sounds continuously from the acoustic environment during speaking despite the potential for sensory masking by self-generated sounds. It is also essential for the auditory system to monitor feedback of one's own voice. This self-monitoring may play a part in distinguishing between self-generated or externally generatedauditory inputs and in detecting errors in our vocal production. Previous work in humans and other animals has demonstrated that the auditory cortex is largely suppressed during speaking or vocalizing. Despite the importance of self-monitoring, the underlying neural mechanisms in the mammalian brain, in particular the role of vocalization-induced suppression, remain virtually unknown. Here we show that neurons in the auditory cortex of marmoset monkeys (Callithrix jacchus) are sensitive to auditory feedback during vocal production, and that changes in the feedback alter the coding properties of these neurons. Furthermore, we found that the previously described cortical suppression during vocalization actually increased the sensitivity of these neurons to vocal feedback. This heightened sensitivity to vocal feedback suggests that these neurons may have an important role in auditory self-monitoring.

The evaluation of comprehensive community-based injury prevention programmes is complex and poses many methodological challenges. There is little consensus in contemporary literature about the most appropriate methods of evaluating these programmes. This study employed a systematic literature review to examine evaluations of 16 community-based injury prevention programmes with regard to key methodological issues and challenges. Three aspects of the evaluated programmes were analysed: assessed elements (context, structure, process, impact, and outcome); study design; and methodological issues addressed. The results showed that context, structure and process assessments were the most neglected aspects of the evaluation studies. The programmes were typically described with minimal discussion of how the context may have influenced the effectiveness. The process (activities) was described rather than evaluated against appropriate standards of comparisons. Impact evaluations adhered more closely to documented guidelines, but half of the evaluations did not include impact variables. Outcome evaluations focused on injury incidence. Most evaluations employed some qualitative methods, but the vast majority of methods used were quantitative. This study indicated that the quasi-experimental study design has become an accepted norm for the evaluation of community-based injury prevention programmes. Most of the evaluations contained explicit details of the methodology used and of the choices related to the methodology. While threats to internal validity were identified in most studies, problems related to external validity and construct validity were largely overlooked by the evaluators.

Effects of social isolation on 50-kHz ultrasonic vocalizations, affective state, cognition, and neurotransmitter concentrations in the ventral tegmental and locus coeruleus of adult rats

It has been argued that a necessary condition for the emergence of speech in humans is the ability to vocalise irrespective of underlying affective states, but when and how this happens during development remains unclear. To examine this, we used wearable microphones and autonomic sensors to collect multimodal naturalistic datasets from 12-month-olds and their caregivers. We observed that, across the day, clusters of vocalisations occur during elevated infant and caregiver arousal. This relationship is stronger in infants than caregivers: caregivers vocalisations show greater decoupling with their own states of arousal, and their vocal production is more influenced by the infant’s arousal than their own. Different types of vocalisation elicit different patterns of change across the dyad. Cries occur following reduced infant arousal stability and lead to increased child-caregiver arousal coupling, and decreased infant arousal. Speech-like vocalisations also occur at elevated arousal, but lead to longer-lasting increases in arousal, and elicit more parental verbal responses. Our results suggest that: 12-month-old infants’ vocalisations are strongly contingent on their arousal state (for both cries and speech-like vocalisations), whereas adults’ vocalisations are more flexibly tied to their own arousal; that cries and speech-like vocalisations alter the intra-dyadic dynamics of arousal in different ways, which may be an important factor driving speech development; and that this selection mechanism which drives vocal development is anchored in our stress physiology.

Speech perception relies on auditory and visual cues and there are strong links between speech perception and production. We aimed to evaluate the role of auditory and visual modalities on speech perception and production in adults with impaired hearing or sight versus those with normal hearing and sight. We examined speech perception and production of three isolated vowels (/i/, /y/, /u/), which were selected based on their different auditory and visual perceptual saliencies, in 12 deaf adults who used one or two cochlear implants (CIs), 14 congenitally blind adults, and 16 adults with normal sight and hearing. The results showed that the deaf adults who used a CI had worse vowel identification and discrimination perception and they also produced vowels that were less typical or precise than other participants. They had different tongue positions in speech production, which possibly partly explains the poorer quality of their spoken vowels. Blind individuals had larger lip openings and smaller lip protrusions for the rounded vowel and unrounded vowels, compared to the other participants, but they still produced vowels that were similar to those produced by the adults with normal sight and hearing. In summary, the deaf adults, even though they used CIs, had greater difficulty in producing accurate vowel targets than the blind adults, whereas the blind adults were still able to produce accurate vowel targets, even though they used different articulatory strategies.

Effects of testosterone on speech production and perception: Linking hormone levels in males to vocal cues and female voice attractiveness ratings

This paper presents a discussion of methodological issues that are relevant and idiosyncratic to cross-cultural research. One characteristic that typifies cross-cultural studies is their comparative nature, i.e., they involve a comparison across two separate cultures on a focal phenomenon. When differences across cultures are observed, the question arises as to whether the results are true cultural differences or merely measurement artifacts. Methodological considerations in cross-cultural research focus on ruling out alternative explanations for these differences and thus enhancing the interpretability of the results. The paper presents an overview of key methodological issues in cross-cultural research and reviews methods of preventing or detecting methodological problems.

Globally, cross-cultural research has become increasingly essential. It is argued that the need for culturally competent social care requires knowledge of the social and cultural contexts of the people and this can be obtained by research, and particularly a qualitative approach. Despite the increased demands on cross-cultural research, discussions on "culturally sensitive methodologies" are still largely neglected in the literature on research methods including qualitative research. As a result, researchers who are working within socially responsible research in cross-cultural settings often confront many challenges with very little information on how to deal with these difficulties. Conducting cross-cultural research is rife with ethical and methodological challenges. This chapter first discusses the essence of qualitative research in cross-cultural research. Some ethical issues and cross-cultural research as well as theoretical standpoints that sit neatly within the framework of cross-cultural research are then included. The last two parts of the chapter are dedicated to the positionality of researchers and language issues in cross-cultural research.