For release: April 3, 2013
For press information, contact Curt Guenther, 901-678-2843
Research led by University of Memphis Professor Kimbrough Oller has been published
in the Proceedings of the National Academy of Sciences (PNAS), one of the most prestigious
scientific journals in the world. It appears in the publication’s current online edition.
The research deals with human infant sounds occurring by three months of age and with
how evaluation of those sounds may reveal deep roots of human language, hinting at
a very distant break from our primate relatives.
Oller holds the Plough Chair of Excellence in the U of M’s School of Communication
Sciences and Disorders. He is also associated with the Institute for Intelligent
Systems at the U of M and with the Konrad Lorenz Institute for Evolution and Cognition
Research in Klosterneuburg, Austria. The research was co-authored by Dr. Eugene Buder
of U of M along with former PhD students and colleagues at other institutions.
The research was funded by the National Institutes for Health.
The article claims that the first vocal changes that occurred as humans evolved away
from their primate background on the way to language did not involve producing sentences
or words, but instead involved primitive sounds expressing flexible functions and
intentions. “Key answers about where language came from may be found in the human
infant’s voice and face,” Oller said, “in the first free vocal expressions of joy
and pain and in the peaceful vocal expressions of comfort. By three months of age
the human infant can already attach various states of emotion (as seen through facial
expressions) to squealing, growling, and cooing, with each of these sound types connected
to different emotions on different occasions. So, each of these precursors to speech
can be produced along with facially expressed joy or distress, or with no apparent
emotion at all. Sounds with such freedom of expression are not known to occur in
any other primate at any age, but language requires such freedom of expression all
The new paper by Oller and colleagues in PNAS demonstrates the vast difference in
the first months of life between infants’ crying and laughter, which have fixed emotional
functions (distress or playfulness) similar to those often seen in nonhuman primates,
as opposed to the human infant sounds that can be used with flexible functions (squealing,
growling and cooing) that appear to be absent in nonhumans. The authors point out
that language could not exist without the sort of freedom of vocal expression found
in the very young human infant, because all aspects of language are dependent upon
flexibility of the usage of vocalizations. The authors argue that as the evolution
of language began, it was necessary for it to start with such primitive beginnings,
similar to primitive baby talk.
More information about Oller’s research is available in volumes he has written and
edited, such as The Emergence of the Speech Capacity (Erlbaum, 2000), The Evolution of Communication Systems (MIT Press, 2004), The Evolution of Communicative Flexibility (MIT Press, 2008), or in his many articles (see website at http://umwa.memphis.edu/fcv/viewprofile.php?uuid=koller).