Dr Sulzberger has found that the best way to learn a language is through frequent exposure to its sound patterns—even if you haven't a clue what it all means.
"However crazy it might sound, just listening to the language, even though you don't understand it, is critical. A lot of language teachers may not accept that," he says.
"Our ability to learn new words is directly related to how often we have been exposed to the particular combinations of the sounds which make up the words. If you want to learn Spanish, for example, frequently listening to a Spanish language radio station on the internet will dramatically boost your ability to pick up the language and learn new words."
Dr Sulzberger's research challenges existing language learning theory. His main hypothesis is that simply listening to a new language sets up the structures in the brain required to learn the words.
"Neural tissue required to learn and understand a new language will develop automatically from simple exposure to the language—which is how babies learn their first language," Dr Sulzberger says.
He was prompted to undertake the research after spending seven years teaching Russian to New Zealand students and observing drop-out patterns.
"I was very conscious of the huge difficulties students have when they tackle another language, especially at the beginning. Many drop out because they feel they are not making progress."
Dr Sulzberger says he was interested in what makes it so difficult to learn foreign words when we are constantly learning new ones in our native language. He found the answer in the way the brain develops neural structures when hearing new combinations of sounds.
"When we are trying to learn new foreign words we are faced with sounds for which we may have absolutely no neural representation. A student trying to learn a foreign language may have few pre-existing neural structures to build on in order to remember the words."
Dr Sulzberger looked for ways people could develop these structures to make the learning process easier. His finding was simple: extensive exposure to the language, something made easier by globalisation and new technology.
"It is easier to learn languages these days because they are so accessible now. You can go home and watch the news in French on the internet."
He says people trying to learn a foreign language in their home country are at a disadvantage compared to those who travel to another country and immerse themselves in its sounds and culture. For the same reason, he says, we need to rethink the way languages are taught.
"Teachers should recognise the importance of extensive aural exposure to a language. One hour a day of studying French text in a classroom is not enough—but an extra hour listening to it on the iPod would make a huge difference," Dr Sulzberger says.
"Language is a skill, it's not like learning a fact. If you want to be a weight lifter, you've got to develop the muscle - you can't learn weightlifting from a book. To learn a language you have to grow the appropriate brain tissue, and you do this by lots of listening—songs and movies are great!"