Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Rats can tell two languages apart from speech cues, sharing an ability with humans and monkeys

10.01.2005


They’re the third type of mammal shown to have this skill

Mammals other than humans can distinguish between different speech patterns. Neuroscientists in Barcelona report that rats, like humans (newborn and adult) and Tamarin monkeys, can extract regular patterns in language from speech (prosodic) cues. The report appears in the January issue of the Journal of Experimental Psychology: Animal Behavior Processes, which is published by the American Psychological Association.

This study of 16 rats per each of four conditions showed that they were able to pick up enough cues from the rhythm and intonation of human speech to tell spoken Dutch from spoken Japanese. After the researchers trained rats to press a lever when hearing a synthesized five-second sentence in Dutch or Japanese, they tested the rats’ response to the alternative language. Rats rewarded for responding to Japanese did not respond to Dutch and vice versa. They pressed the lever only for the language to which they’d been exposed. What’s more, the rats generalized the ability to differentiate to new Dutch and new Japanese sentences they had not heard before.



This special ability to detect the features that distinguish one type of speech from another – enabled by a test using two very different spoken languages – has now been documented in three different mammalian species: Humans (both newborn and adult), Tamarin monkeys, and now rats. Scientists study Tamarin monkeys because they can use the same kinds of experiments that they use for infants, allowing for direct comparison. The rats were the first non-primate mammal studied; research on non-mammalian species (such as songbirds) may shed light on whether this ability is unique to mammals.

The rats’ linguistic sophistication was limited. When experimenters used different humans to speak each sentence, the rats found it much hard to tell the languages apart. Humans, even in early infancy, can overcome this problem – and only get better at it by learning a lexicon and syntax, phonology (letter sounds), word segments, and semantic information (what words mean).

Author Juan Toro, who is about to earn his PhD, says the results were surprising. "It was striking to find that rats can track certain information that seems to be so important in language development in humans," he says. The research, he adds, shows "which abilities that humans use for language are shared with other animals, and which are uniquely human. It also suggests what sort of evolutionary precursors language might have."

Toro cautions that just because the rats share an ability with humans doesn’t mean they use it the same way. He says, "Rats have not evolved the ability to track prosodic cues for linguistic requirements. It is more likely that they do it as a byproduct of other abilities that have some evolutionary relevance for them. The idea that species can use certain structures for a different function than that for which they evolved is not new. For example, human newborns coordinate all the speech information they take in to eventually make sense of language, something that a rat is not likely to do."

It is very likely, he and his co-authors suspect, that the ability to tell apart two different languages is a byproduct of more general perceptual abilities used for detecting time order through hearing – a useful adaptation for the rat. Thus, he adds, "rats can co-opt these abilities to differentiate sentences by detecting their prosodic regularities."

Pam Willenz | EurekAlert!
Further information:
http://www.apa.org
http://www.apa.org/releases/speech_article.pdf

More articles from Life Sciences:

nachricht How molecules teeter in a laser field
18.01.2019 | Forschungsverbund Berlin

nachricht Discovery of enhanced bone growth could lead to new treatments for osteoporosis
18.01.2019 | University of California - Los Angeles

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Ten-year anniversary of the Neumayer Station III

The scientific and political community alike stress the importance of German Antarctic research

Joint Press Release from the BMBF and AWI

The Antarctic is a frigid continent south of the Antarctic Circle, where researchers are the only inhabitants. Despite the hostile conditions, here the Alfred...

Im Focus: Ultra ultrasound to transform new tech

World first experiments on sensor that may revolutionise everything from medical devices to unmanned vehicles

The new sensor - capable of detecting vibrations of living cells - may revolutionise everything from medical devices to unmanned vehicles.

Im Focus: Flying Optical Cats for Quantum Communication

Dead and alive at the same time? Researchers at the Max Planck Institute of Quantum Optics have implemented Erwin Schrödinger’s paradoxical gedanken experiment employing an entangled atom-light state.

In 1935 Erwin Schrödinger formulated a thought experiment designed to capture the paradoxical nature of quantum physics. The crucial element of this gedanken...

Im Focus: Nanocellulose for novel implants: Ears from the 3D-printer

Cellulose obtained from wood has amazing material properties. Empa researchers are now equipping the biodegradable material with additional functionalities to produce implants for cartilage diseases using 3D printing.

It all starts with an ear. Empa researcher Michael Hausmann removes the object shaped like a human ear from the 3D printer and explains:

Im Focus: Elucidating the Atomic Mechanism of Superlubricity

The phenomenon of so-called superlubricity is known, but so far the explanation at the atomic level has been missing: for example, how does extremely low friction occur in bearings? Researchers from the Fraunhofer Institutes IWM and IWS jointly deciphered a universal mechanism of superlubricity for certain diamond-like carbon layers in combination with organic lubricants. Based on this knowledge, it is now possible to formulate design rules for supra lubricating layer-lubricant combinations. The results are presented in an article in Nature Communications, volume 10.

One of the most important prerequisites for sustainable and environmentally friendly mobility is minimizing friction. Research and industry have been dedicated...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

Our digital society in 2040

16.01.2019 | Event News

11th International Symposium: “Advanced Battery Power – Kraftwerk Batterie” Aachen, 3-4 April 2019

14.01.2019 | Event News

ICTM Conference 2019: Digitization emerges as an engineering trend for turbomachinery construction

12.12.2018 | Event News

 
Latest News

Additive manufacturing reflects fundamental metallurgical principles to create materials

18.01.2019 | Materials Sciences

How molecules teeter in a laser field

18.01.2019 | Life Sciences

The cytoskeleton of neurons has been found to be involved in Alzheimer's disease

18.01.2019 | Health and Medicine

VideoLinks
Science & Research
Overview of more VideoLinks >>>