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 Flavins keep a handy helper in their pocket
25.04.2018 | University of Freiburg

nachricht Complete skin regeneration system of fish unraveled
24.04.2018 | Tokyo Institute of Technology

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: BAM@Hannover Messe: innovative 3D printing method for space flight

At the Hannover Messe 2018, the Bundesanstalt für Materialforschung und-prüfung (BAM) will show how, in the future, astronauts could produce their own tools or spare parts in zero gravity using 3D printing. This will reduce, weight and transport costs for space missions. Visitors can experience the innovative additive manufacturing process live at the fair.

Powder-based additive manufacturing in zero gravity is the name of the project in which a component is produced by applying metallic powder layers and then...

Im Focus: Molecules Brilliantly Illuminated

Physicists at the Laboratory for Attosecond Physics, which is jointly run by Ludwig-Maximilians-Universität and the Max Planck Institute of Quantum Optics, have developed a high-power laser system that generates ultrashort pulses of light covering a large share of the mid-infrared spectrum. The researchers envisage a wide range of applications for the technology – in the early diagnosis of cancer, for instance.

Molecules are the building blocks of life. Like all other organisms, we are made of them. They control our biorhythm, and they can also reflect our state of...

Im Focus: Spider silk key to new bone-fixing composite

University of Connecticut researchers have created a biodegradable composite made of silk fibers that can be used to repair broken load-bearing bones without the complications sometimes presented by other materials.

Repairing major load-bearing bones such as those in the leg can be a long and uncomfortable process.

Im Focus: Writing and deleting magnets with lasers

Study published in the journal ACS Applied Materials & Interfaces is the outcome of an international effort that included teams from Dresden and Berlin in Germany, and the US.

Scientists at the Helmholtz-Zentrum Dresden-Rossendorf (HZDR) together with colleagues from the Helmholtz-Zentrum Berlin (HZB) and the University of Virginia...

Im Focus: Gamma-ray flashes from plasma filaments

Novel highly efficient and brilliant gamma-ray source: Based on model calculations, physicists of the Max PIanck Institute for Nuclear Physics in Heidelberg propose a novel method for an efficient high-brilliance gamma-ray source. A giant collimated gamma-ray pulse is generated from the interaction of a dense ultra-relativistic electron beam with a thin solid conductor. Energetic gamma-rays are copiously produced as the electron beam splits into filaments while propagating across the conductor. The resulting gamma-ray energy and flux enable novel experiments in nuclear and fundamental physics.

The typical wavelength of light interacting with an object of the microcosm scales with the size of this object. For atoms, this ranges from visible light to...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

Invitation to the upcoming "Current Topics in Bioinformatics: Big Data in Genomics and Medicine"

13.04.2018 | Event News

Unique scope of UV LED technologies and applications presented in Berlin: ICULTA-2018

12.04.2018 | Event News

IWOLIA: A conference bringing together German Industrie 4.0 and French Industrie du Futur

09.04.2018 | Event News

 
Latest News

Getting electrons to move in a semiconductor

25.04.2018 | Physics and Astronomy

Reconstructing what makes us tick

25.04.2018 | Physics and Astronomy

Cheap 3-D printer can produce self-folding materials

25.04.2018 | Information Technology

VideoLinks
Science & Research
Overview of more VideoLinks >>>