The paidologos project was a large cross-linguistic investigation of phonological development that was supported by NIDCD funding between 2003 and 2010. The project was inspired by the fact that words in different languages are made up of different sounds and sound sequences, and sounds that are common in some languages are rare in others. For example, English words can't start with the sequence of sounds "kyo," but many words in Japanese do. The "th" sound, like in the words "think" and "myth" doesn't occur in many words of English, but it occurs in lots of words of Greek. Also, sounds that we think of as the same across languages, like the "s" and "sh" in the English pronunciation of the word "sushi" and these sounds in a Japanese speaker's pronunciation of the word , are somewhat different when we measure them closely. The focus of the paidologos project was to examine how these differences affect how children learn to speak different languages.
The name paidologos is a new word that we made up from Greek roots meaning child and word, in order to capture our idea of looking at children’s words in parallel across different languages. 
To do that, we traveled to day care centers and children’s homes in Hong Kong, eastern Japan, northern Greece, the far northeast of China, South Korea, and central Ohio to record the speech of two- to five-year-old children who were learning to speak Cantonese, Japanese, Greek, Mandarin Chinese, Korean, or English. Associated colleagues in Taiwan, New Caledonia, and France are currently collecting similar data for children who are learning to speak Taiwanese, Drehu, Taihitan, or French, as well as some data from children who are learning to speak two languages -- e.g., Taiwanese and Mandarin or Drehu and French.
While the collection and analysis of the data are still ongoing, lots of interesting things have already been found. For example, we found that children's learning of a sound is affected by how frequently it occurs in a language (like the "th" of Greek and the "th" of English). We also found that seemingly minor differences across languages (like the differences between the "s" in English and Japanese) can have a big influence on how children learn to say words of the language that they’re learning.
The Paidologos project was supported by:
- A grant from the National Institute for Deafness and Other Communication Disorders (NIDCD 02932), "A cross-linguistic examination of phonological development"
- A 2007 Target Investment Interdisciplinary Fellowship from Ohio State University to Fangfang Li and Eunjong Kong
- A grant awarded to Li-mei Chen from the Ministry of Education in Taiwan, R.O.C
- A "Prix d'Encouragement à la Recherche (PER)" grant from New Caledonia awarded to Julia Monnin
For more information on this project, please go to: www.ling.ohio-state.edu/pdlg/.