Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

From robotics to animal motor-control systems

23.03.2009
Multiple timescales of neural activities are important to motor-control systems in animals, according to research using robots

Programmers of robots have long been challenged by the difficulty of implementing some of the simplest of human activities, such as walking up stairs or digging a ditch.

This is partially due to the versatility of human motor behavior in varying situations. Such robustness can be achieved with a functional hierarchy: a division of labor that allows complex motor behaviors to arise from simpler tasks that are connected at a higher level.

Previously, researchers had theorized that a connection of reusable sub-movements called motor primitives would be represented by spatially localized networks in the brain. Now, Yuichi Yamashita and Jun Tani from the RIKEN Brain Science Institute, Wako, have shown that the temporal characteristics of neurons in these motor networks may be just as critical to their functional hierarchy (1).

Yamashita and Tani took a synthetic approach to test their hypothesis that multiple timescales of activity could mediate motor organization. To this end, the scientists trained a robot to complete a set of distinct, but related, tasks. These motor behaviors included picking up a block to shake it side to side, picking up a block to shake it up and down, and touching the top of a block with one hand.

“It is generally thought that diverse behavior of an animal results from a functional hierarchy of the motor-control system,” explains Yamashita, where “motor primitives are flexibly integrated.” For example, the robot’s tasks could be executed by mixing and matching such primitives as making contact with an object, lifting it, and shaking it.

The key distinction in Yamashita and Tani’s work was that the hierarchical organization arose from multiple timescales in the network activity, rather than through spatial connections. The spatially based networks of previous studies consisted of isolated modules responding to each primitive in the lower levels, and gates to select and switch between primitives in the higher levels.

By contrast, the neural network of Yamashita and Tani’s robot comprised fast units, which could respond quickly to changing inputs, and slow units, which tended to avoid rapid fluctuations by relying on previous states. Based on the network activity, it appeared that the fast units had spontaneously organized to represent motor primitives, whereas the slow units resembled gates that ordered and activated the primitives. This discovery helps to explain the puzzling discrepancy between previous theories of spatially based motor organization and the elusive evidence of such spatial organization in the animal brain.

Reference

1. Yamashita, Y. & Tani, J. Emergence of functional hierarchy in a multiple timescale neural network model: A humanoid robot experiment. PLoS Computational Biology 4, e1000220 (2008).

The corresponding author for this highlight is based at the RIKEN Laboratory for Behavior and Dynamic Cognition

Saeko Okada | Research asia research news
Further information:
http://www.researchsea.com
http://www.rikenresearch.riken.jp/research/663/

More articles from Interdisciplinary Research:

nachricht Fighting myocardial infarction with nanoparticle tandems
04.12.2017 | Rheinische Friedrich-Wilhelms-Universität Bonn

nachricht Virtual Reality for Bacteria
01.12.2017 | Institute of Science and Technology Austria

All articles from Interdisciplinary Research >>>

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 >>>