Why Does Speaking in a Cute Voice Make You Sound Cuter? Scientists Find a Clue [Unboxing the Lab]

[Financial News] A study has found that when adult women use cute speech, the resonance frequency of vowels produced in the throat and mouth, known as F1, is about 28 Hz higher than in ordinary speech. The research team suggested that this change may reflect an attempt to imitate the sound characteristics of a child’s short vocal tract.
Professor Kim Ji-eun of Duksung Women's University’s Korean Language and Literature department and a research team at the University of Zurich in Switzerland published a joint paper on the findings in the international journal of acoustics, JASA Express Letters. The study focused on the idea that cute speech does not simply mean raising the voice or changing intonation, but also produces certain changes in the sounds made when vowels are articulated.

This study examined the cute speech commonly used in Korea, but it could serve as a starting point for comparisons with affectionate speech in other countries.
In Chinese, there is "sajiao," a way of speaking cutely to someone close, and in Japanese there is "burikko." English and German also have cases of speaking like a baby to someone familiar. The research team plans to compare what acoustic features these speech styles show across languages and cultures.
They also plan to examine how the length of the vocal tract, the passage through which the voice actually travels, changes when people use cute speech. In addition, they will study whether listeners feel closer to the speaker or show a protective response after hearing this style of speech.

The research team conducted an experiment with 12 adults aged 25 to 31 who speak the Seoul dialect. There were six men and six women.
The participants read 29 advertising-style sentences in a soundproof lab. First, they read them in cute speech, and then they read the same sentences in a normal tone. Having the same person read the same sentences in two different ways helped reduce the influence of individual voice differences and sentence content on the results.
The team used computer software to analyze how vowel sounds differed between the two speech styles. When people pronounce vowels such as "a," "i," and "u," a distinctive resonance is created as the sound passes through the throat and mouth. Among several numerical measures used to describe these sound characteristics, the researchers compared a value called F1.

The analysis showed that F1 was about 28 Hz higher in cute speech than in ordinary speech. This change was statistically confirmed across all vowels, and the difference was even larger for some vowels.
F1 is a numerical measure of sound that changes depending on the structure of the throat and mouth when a person pronounces vowels. Because children have a shorter vocal tract, the passage from the throat to the mouth, their F1 tends to be relatively higher than that of adults.
The research team said that the rise in F1 when adults use cute speech may also be part of an effort to imitate these childlike sound characteristics. However, because the study analyzed only sound changes, it did not confirm how the vocal tract actually changed or how the tongue and other speech organs moved. Those real vocal processes will need further study.
Co-author Volker Dellwo of the University of Zurich explained, "In animals, strategies are sometimes used to lengthen the vocal tract in order to appear larger. These findings suggest that humans may use the opposite strategy," and added, "They make their voice sound smaller and more childlike through cute speech."

[email protected] Kim Man-gi Reporter