Using a measure called the mel-frequency cepstrum, Princeton researchers have identified consistent shifts in vocal timbre between mothers speaking to their children and speaking to other adults.

Timbre, the tone color or unique quality of a sound, is a spectral fingerprint that helps us instantly identify and classify sound sources, such as individual people and musical instruments. 

This research was conducted in the Princeton Baby Lab and was led by postdoctoral research associates Elise Piazza and Marius Cătălin Iordan with the Princeton Neuroscience Institute,  as well as Casey Lew-Williams, an assistant professor of psychology. 

^{Photo by: Nick Donnoli, Office of Communications. From left: Casey Lew-Williams, Elise Piazza and Marius Cătălin Iordan research child development in the Princeton Baby Lab}

Full Story
Uncovering the sound of ‘motherese,’ baby talk across languages