Spanish Rats Learn Japanese

This morning I came across this story (via Language Log), which is based on this paper. Researchers have trained rats to respond to either Japanese or Dutch, and then tested them in several conditions. During the testing phase, rats were able to recognize new sentences from the language on which they were trained, but not sentences from the other language. However, when the sentences heard during the testing phase were spoken by a new voice, or were played backwards, rats were unable to distingiush between the two languages. From these results, the authors draw the following conclusions:

In summary, rats’ abilities to extract prosodic cues from sentences of two different languages are greater than previously thought, for they can generalize those features to new sentences, while maintaining on the recurrent pattern of not being able to use any cue when sentences are played backward. When faced with the problem of different speakers, rats also have more difficulty in effectively discriminating among sentences. This difficulty is found as well in human infants, but eventually, they overcome it in order to acquire lexical and syntactic aspects of the language, and combine them with phonotactic, segmental, and semantic information.

Just to tie this in to what I've posted about over the last couple days, the authors also note that their finding is consistent with the view of a certain linguistic trio, writing:

[T]he ability to bootstrap linguistic regularities from low-level cues, such as rhythm, may represent the use for linguistic purposes of an already-existing ability present in the mammalian auditory system, as has been proposed by Hauser, Chomsky, and Fitch (2002).