Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Monkey math machinery is like humans’

01.11.2005


Monkeys have a semantic perception of numbers that is like humans’ and which is independent of language, Duke University cognitive neuroscientists have discovered. They said their findings demonstrate that the neural mechanism underlying numerical perception is evolutionarily primitive.



Jessica Cantlon and Elizabeth Brannon described their findings with macaque monkeys in an article published online the week of Oct. 31, 2005, in the Early Edition of the Proceedings of the National Academies of Science. Cantlon is a graduate student and Brannon is an assistant professor in the Department of Psychological and Brain Sciences, as well as a member of the Center for Cognitive Neuroscience. Their work was supported by the National Institute for Child Health and Development, The National Science Foundation and a John Merck Scholars Award.

In their experiments, the researchers sought to test whether monkeys show a phenomenon known as "semantic congruity" when making numerical comparisons.


"When adult humans compare any two things, such as the size of two animals, and they’re asked ’which is smaller, an ant or a rat?’ one might think it’s the same kind of question as ’which is larger, an ant or a rat?’" said Brannon. "But humans are faster at saying an ant is smaller than saying a rat is larger. By contrast, if the two animals are large, such as a cow or an elephant, they’re quicker at saying the elephant is larger than saying the cow is smaller. This ’semantic congruity’ holds for all kinds of comparisons, including numbers and distances.

"It would seem that this is entirely a linguistic effect, totally dependent on language," said Brannon. "But we sought to understand whether monkeys showed this semantic effect, even though they don’t have language."

In their experiments, Cantlon and Brannon presented monkeys with two arrays of randomized numbers of dots displayed on a computer touch screen at randomized positions. However, instead of using language to instruct the monkeys to "choose larger" or "choose smaller" the researchers made the background blue if the monkeys were to choose the larger number and red if the smaller number. The monkeys were rewarded with a sip of a sweet drink for correct answers.

"Our results showed a very large semantic congruity effect," said Cantlon. "For example, when the number pair was small, such as two versus three, the monkeys were much faster at choosing the smaller compared to the larger of the pair. We were also impressed at the high level of accuracy the monkeys achieved on this difficult conditional discrimination," she said.

"Clearly, even though their capability has nothing to do with language, it is nevertheless semantic in that the red and blue color cues carry meaning for the monkeys," said Cantlon.

Brannon said the new findings represent further evidence of the fundamental similarity in numerical thinking in human and non-human primates.

Said Brannon "This is another piece of the puzzle showing us that the comparison mechanism that the monkeys use is, as far as we can tell, the same mechanism that humans are using." More broadly, she said, the findings yield insight into the role – or lack of a role – that language plays in the process.

"The ability to use language is obviously one of the major differences in the way humans and animals function in the world," she said. "However, these experiments clearly show that this semantic congruity effect, which we thought was language-dependent, is not."

Dennis Meredith | EurekAlert!
Further information:
http://www.duke.edu

More articles from Life Sciences:

nachricht More genes are active in high-performance maize
19.01.2018 | Rheinische Friedrich-Wilhelms-Universität Bonn

nachricht How plants see light
19.01.2018 | Albert-Ludwigs-Universität Freiburg im Breisgau

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Artificial agent designs quantum experiments

On the way to an intelligent laboratory, physicists from Innsbruck and Vienna present an artificial agent that autonomously designs quantum experiments. In initial experiments, the system has independently (re)discovered experimental techniques that are nowadays standard in modern quantum optical laboratories. This shows how machines could play a more creative role in research in the future.

We carry smartphones in our pockets, the streets are dotted with semi-autonomous cars, but in the research laboratory experiments are still being designed by...

Im Focus: Scientists decipher key principle behind reaction of metalloenzymes

So-called pre-distorted states accelerate photochemical reactions too

What enables electrons to be transferred swiftly, for example during photosynthesis? An interdisciplinary team of researchers has worked out the details of how...

Im Focus: The first precise measurement of a single molecule's effective charge

For the first time, scientists have precisely measured the effective electrical charge of a single molecule in solution. This fundamental insight of an SNSF Professor could also pave the way for future medical diagnostics.

Electrical charge is one of the key properties that allows molecules to interact. Life itself depends on this phenomenon: many biological processes involve...

Im Focus: Paradigm shift in Paris: Encouraging an holistic view of laser machining

At the JEC World Composite Show in Paris in March 2018, the Fraunhofer Institute for Laser Technology ILT will be focusing on the latest trends and innovations in laser machining of composites. Among other things, researchers at the booth shared with the Aachen Center for Integrative Lightweight Production (AZL) will demonstrate how lasers can be used for joining, structuring, cutting and drilling composite materials.

No other industry has attracted as much public attention to composite materials as the automotive industry, which along with the aerospace industry is a driver...

Im Focus: Room-temperature multiferroic thin films and their properties

Scientists at Tokyo Institute of Technology (Tokyo Tech) and Tohoku University have developed high-quality GFO epitaxial films and systematically investigated their ferroelectric and ferromagnetic properties. They also demonstrated the room-temperature magnetocapacitance effects of these GFO thin films.

Multiferroic materials show magnetically driven ferroelectricity. They are attracting increasing attention because of their fascinating properties such as...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

10th International Symposium: “Advanced Battery Power – Kraftwerk Batterie” Münster, 10-11 April 2018

08.01.2018 | Event News

See, understand and experience the work of the future

11.12.2017 | Event News

Innovative strategies to tackle parasitic worms

08.12.2017 | Event News

 
Latest News

Let the good tubes roll

19.01.2018 | Materials Sciences

How cancer metastasis happens: Researchers reveal a key mechanism

19.01.2018 | Health and Medicine

Meteoritic stardust unlocks timing of supernova dust formation

19.01.2018 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>