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 Newly designed molecule binds nitrogen
23.02.2018 | Julius-Maximilians-Universität Würzburg

nachricht Atomic Design by Water
23.02.2018 | Max-Planck-Institut für Eisenforschung GmbH

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Attoseconds break into atomic interior

A newly developed laser technology has enabled physicists in the Laboratory for Attosecond Physics (jointly run by LMU Munich and the Max Planck Institute of Quantum Optics) to generate attosecond bursts of high-energy photons of unprecedented intensity. This has made it possible to observe the interaction of multiple photons in a single such pulse with electrons in the inner orbital shell of an atom.

In order to observe the ultrafast electron motion in the inner shells of atoms with short light pulses, the pulses must not only be ultrashort, but very...

Im Focus: Good vibrations feel the force

A group of researchers led by Andrea Cavalleri at the Max Planck Institute for Structure and Dynamics of Matter (MPSD) in Hamburg has demonstrated a new method enabling precise measurements of the interatomic forces that hold crystalline solids together. The paper Probing the Interatomic Potential of Solids by Strong-Field Nonlinear Phononics, published online in Nature, explains how a terahertz-frequency laser pulse can drive very large deformations of the crystal.

By measuring the highly unusual atomic trajectories under extreme electromagnetic transients, the MPSD group could reconstruct how rigid the atomic bonds are...

Im Focus: Developing reliable quantum computers

International research team makes important step on the path to solving certification problems

Quantum computers may one day solve algorithmic problems which even the biggest supercomputers today can’t manage. But how do you test a quantum computer to...

Im Focus: In best circles: First integrated circuit from self-assembled polymer

For the first time, a team of researchers at the Max-Planck Institute (MPI) for Polymer Research in Mainz, Germany, has succeeded in making an integrated circuit (IC) from just a monolayer of a semiconducting polymer via a bottom-up, self-assembly approach.

In the self-assembly process, the semiconducting polymer arranges itself into an ordered monolayer in a transistor. The transistors are binary switches used...

Im Focus: Demonstration of a single molecule piezoelectric effect

Breakthrough provides a new concept of the design of molecular motors, sensors and electricity generators at nanoscale

Researchers from the Institute of Organic Chemistry and Biochemistry of the CAS (IOCB Prague), Institute of Physics of the CAS (IP CAS) and Palacký University...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

2nd International Conference on High Temperature Shape Memory Alloys (HTSMAs)

15.02.2018 | Event News

Aachen DC Grid Summit 2018

13.02.2018 | Event News

How Global Climate Policy Can Learn from the Energy Transition

12.02.2018 | Event News

 
Latest News

Basque researchers turn light upside down

23.02.2018 | Physics and Astronomy

Finnish research group discovers a new immune system regulator

23.02.2018 | Health and Medicine

Attoseconds break into atomic interior

23.02.2018 | Physics and Astronomy

VideoLinks
Science & Research
Overview of more VideoLinks >>>