Why Study Music and Speech Together?
Researchers have long wondered how human language developed into the state in which it currently exists, and few considered how a culture’s music might provide insight into its language as well. Music and speech are intrinsically linked—both as a means of communication and a manner of self-expression. Thus, researchers posited that discovering what is similar (and different) between speech and music, both within a language and across languages, could provide greater insight into how language came to be the way it is in the first place.
How the Study Worked
The in-depth study tread deeply into the roots of multicultural language and song. Dozens of researchers from cultures across the world made four recordings:
- One of them singing a traditional song from their culture
- One of them reciting the lyrics of that song
- One of them verbally describing the meaning of the song
- One of an instrumental version of the song with no words
The researchers then measured multiple factors in these recordings:
- Pitch height [fundamental frequency
- Temporal rate—in other words, the length of breaks between sounds and how quickly the language was uttered
- Pitch stability
- Timbral brightness
- Pitch interval size
- Pitch declination
Once these elements were gathered, the researchers then delved deeper by considering:
- Rhythmic regularity
- Phrase length (duration between two breaths/breaks)
- Pitch interval regularity
- Pitch range
- Intensity
- Pulse clarity
- Timbral noisiness
Roadblocks and Solutions
Of course, measuring language is an arduous tasks, and this research faced numerous challenges. For one, only 85% of the participants who provided language samples were native speakers of the presented language. This potential confounder complicated matters by introducing uncertainty; could non-native speakers replicate the authentic sound of a language?
Additionally, not everyone produced the same content. The speakers for Te Reo Māori and Cherokee submitted their song descriptions in English instead of their native languages. The researchers were still able to use some of their data, but these languages contributed less than others to the overall corpus due to this missing data set.
Another roadblock, which researchers were able to solve, was the difference between female and male vocalizations. By recruiting speakers from male and female cohorts at a nearly even rate (41 to 34, respectively), the data was functionally diverse. Thanks to this extra step, researchers were able to discover that there was no difference other than pitch height, which is only natural given the lower pitch of male voices and the higher pitch of female voices.
What Researchers Discovered
Thanks to the depth of their efforts, the researchers discovered some fascinating insights into how language works. In general, songs were higher pitched by a significant margin and featured a slower temporal rate with a more stabilized pitch. In other words, songs were very consistent and tended to be slower and more predictable than speech—and this was true not just within the same languages, but across all sampled languages.
Conversely, spoken language tends to be faster and varies more substantially in its pitch. Both spoken and sung language remained approximately the same in timbral brightness and pitch interval size.
While all of this information is intriguing, what does it mean? While many potential conclusions could be drawn from the results of this work, the overarching result is that linguists now have stronger evidence than ever of a “universal” relationship between music and speech, no matter the culture or speaker. Put differently, human language seems to have evolved such that cultures that had no contact with each other still developed tendencies in both language and music that are the same.
The researchers suggest multiple possible reasons for this development. For instance, they theorize that perhaps music is more stable and slower is because music encourages synchronization (with instruments, with other singers, etc.) and thus benefits from predictability and ordered pacing. Conversely, spoken language, which may convey on a day-to-day basis any of an impossibly large variety of information, requires greater variability to encapsulate emotion and context.
Regardless of whether a single cause can be identified for the uniform development of both language and music across history and culture, one truth remains: linguists are now closer than ever to understanding how human language developed.
