From China to Tanzania, from Scandinavia to Polynesia, to the Amazon, to Canada: it seems that our species tends to modulate vote in the same way when it is addressed to children. A study published in Nature Human behavior, led by a research group consisting of more than 40 scientists of various nationalities and led by Courtney B. Hilton and Cody J. Moser, respectively from Harvard University in Cambridge (USA) and the University of California in Merced (USA). The conclusions stem from the analysis of more than 1,600 voice recordings that the researchers collected in 21 different communities, spread over six continents.
Hypothesis and data analysis
Earlier it was observed that the different Language of the world seems to favor certain combinations of sounds common to others over all possible ones. The authors of this research wondered whether, even when communicating with children, people belonging to different cultures and speaking different languages use similar vocal modulations. Indeed, when addressing a child we instinctively adopt a different tone than we would use in conversation with an adult, and several studies suggest that this stereotyping has very specific functions, such as encouraging the learning of Language on the part of the child and modulate his temperament or mood. But does this – the scholars wondered – happen in the same way for different cultures? To answer the question, the researchers recorded the responses of 410 survey participants after asking them to give a speech to a baby “Sulky”, then to an adult, and finally to imagine him singing a song addressed again to a child and then to an adult. The resulting 1615 recordings were then analyzed with computational methods – to rule out the introduction of human error due to unconscious bias or preconceptions – to study 15 different types of acoustic characteristics, such as tone, rhythm and timbre.
It turned out that the acoustic characteristics of speeches and songs addressed to children contain similar elements if we compare the 21 different cultures to which the participants in the study belong. Of the 15 characteristics examined, 11 appear to be consistently distinguishable and shared. Especially in all or in most cases taking into account vote by the same participant, a speech addressed to a child is characterized by a higher pitch and a generally wider range of intonations. These characteristics are generally used by various animal species to communicate in non-danger situations, as opposed to the low and hoarse sounds used in situations of aggression or alarm. The researchers therefore assume that there are common roots to be sought in the basic principles of bioacoustics, the science that investigates the use of different forms of animal communication in specific contexts.
Another characteristic of Language addressed to the little ones seems to be a greater clarity in the impulse used to formulate the words. A valid synthesis for all the cultures analyzed is that these elements together would bring musicality to speeches that are typically aimed at children, and end up making them sound like songs.
Involvement of “naive listeners”
The research team then involved a group of randomly selected individuals wondering if they were able to recognize who sounds who offered him to listen. They did it through “Who is listening?”, a citizen science platform that allows volunteers to get involved in research experiments. The “naive listeners” (ignorant listeners), i.e. the 51056 people, residing in 187 different countries of the world, selected from among the participants, were on average able to distinguish a speech addressed to a child from a speech addressed to an adult . Given the variability of the sample and after specific analyses, the researchers concluded that this was not associated with linguistic similarities between those who produced the sounds and those who listened to them. In other words, it appears that the “naive listeners” were able to recognize specific characteristics of language typically aimed at children or adults regardless of the content of what they were listening to and only on the basis of paraverbal elements such as eg. Tone bearing.
An interesting observation, the study authors write, is that there seems to be an obvious tendency to connect I sing, compared to speech, for communication directed at children rather than that directed at adults. A pattern that could agree with the theories that assign singing and music in general a special role in children’s growth and learning.
Limitations of the study
The authors themselves acknowledge that the study has some limitations that must be taken into account. For example, however large and varied the sample of participants was, it is not representative of the entire human species. In order to generalize the conclusions, the study should therefore be further extended. Furthermore, the recorded vocalizations were not produced spontaneously by the participants, but at the request of the researchers, which may have influenced their characteristics. At the same time, the very fact that the recordings were made under as standardized conditions as possible would have made the sample sufficiently homogeneous to be studied in a systematic way.
References: Nature Human Behavior
Image credit: David Brooke Martin on Unsplash