Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Clear vision despite a heavy head - model explains the choice of simple movements

10.11.2011
Simple actions are most often performed in the same manner, despite countless movement possibilities. A mathematical model explains why this is the case.

Using the example of gaze movements, scientists of the Ludwig-Maximilians-University Munich (LMU) and the Bernstein Center Munich show that we unconsciously choose those movements that minimize end point variability. This is true even if the head’s rotational inertia is experimentally altered. The findings could be used to generate more natural robot movements and to better adapt prosthetic devices to human movements.


Weights at the ends of the sticks alter the head‘s rotational inertia. A mathematical model predicts which eye and head movements are chosen during gaze shifts in this situation. Image: Nadine Lehnen, LMU Munich

In one respect, handling a computer mouse is just like looking in the rearview mirror: well established movements help the brain to concentrate on the essentials. But just a simple gaze shift to a new target bears the possibility of an almost infinite number of combinations of eye and head movement: how fast do we move eye and head? How much does the eye rotate, how much the head? Until now, it was unclear why the brain chooses a particular movement option from the set of all possible combinations. A team led by Dr. Stefan Glasauer (LMU), project leader at the Bernstein Center Munich, has now developed a mathematical model that accurately predicts horizontal gaze movements. Besides eye and head contribution to the gaze shift, it also predicts movement duration and velocity.

In contrast to most previous models, the researchers considered the movement of head and eye to the target as well as the counter-movement of the eye after the gaze has reached the target, but the head is still moving. “The longer the movement, the more perturbations add up,” says Glasauer. “However, the faster the movement, the more errors arise from acceleration and large muscle forces.” On the basis of this information, the Munich researchers calculated eye and head movements and determined the movement combination that caused the fewest disturbances. This movement matched that chosen by healthy volunteers - not only in natural conditions but also in an experiment where subjects’ head movements were altered by an experimental increase in the head’s rotational inertia (see picture).

These findings could help teach robots humanoid movements and thus facilitate interaction with service robots. It may also be helpful in the construction of “smart” prostheses. These devices could offer the carrier a choice of movements that come closest to the natural human ones. For the next step, Glasauer and colleagues want to examine three-dimensional eye-head movements and aim to better understand simple movement learning.

The Bernstein Center Munich is part of the National Bernstein Network Computational Neuroscience (NNCN) in Germany. The NNCN was established by the German Federal Ministry of Education and Research with the aim of structurally interconnecting and developing German capacities in the new scientific discipline of computational neuroscience. The network is named after the German physiologist Julius Bernstein (1835–1917).

Original publication:
Saglam M, Lehnen N, Glasauer S (2011): Optimal control of natural eye-head movements minimizes the impact of noise. J Neurosci. 31(45):16185–16193
For further information please contact:
Dr. Stefan Glasauer
sglasauer@nefo.med.uni-muenchen.de
Bernstein Center Munich and
Ludwig-Maximilians-Universität München
Institute of Clinical Neurosciences
Marchioninistr. 23
81377 Munich, Germany
Phone: +49-89-7095-4839

Dr. Simone Cardoso de Oliveira | idw
Further information:
http://www.bccn-munich.de/
http://www.nncn.de/

More articles from Life Sciences:

nachricht Protein 'spy' gains new abilities
28.04.2017 | Rice University

nachricht How Plants Form Their Sugar Transport Routes
28.04.2017 | Universität Heidelberg

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Making lightweight construction suitable for series production

More and more automobile companies are focusing on body parts made of carbon fiber reinforced plastics (CFRP). However, manufacturing and repair costs must be further reduced in order to make CFRP more economical in use. Together with the Volkswagen AG and five other partners in the project HolQueSt 3D, the Laser Zentrum Hannover e.V. (LZH) has developed laser processes for the automatic trimming, drilling and repair of three-dimensional components.

Automated manufacturing processes are the basis for ultimately establishing the series production of CFRP components. In the project HolQueSt 3D, the LZH has...

Im Focus: Wonder material? Novel nanotube structure strengthens thin films for flexible electronics

Reflecting the structure of composites found in nature and the ancient world, researchers at the University of Illinois at Urbana-Champaign have synthesized thin carbon nanotube (CNT) textiles that exhibit both high electrical conductivity and a level of toughness that is about fifty times higher than copper films, currently used in electronics.

"The structural robustness of thin metal films has significant importance for the reliable operation of smart skin and flexible electronics including...

Im Focus: Deep inside Galaxy M87

The nearby, giant radio galaxy M87 hosts a supermassive black hole (BH) and is well-known for its bright jet dominating the spectrum over ten orders of magnitude in frequency. Due to its proximity, jet prominence, and the large black hole mass, M87 is the best laboratory for investigating the formation, acceleration, and collimation of relativistic jets. A research team led by Silke Britzen from the Max Planck Institute for Radio Astronomy in Bonn, Germany, has found strong indication for turbulent processes connecting the accretion disk and the jet of that galaxy providing insights into the longstanding problem of the origin of astrophysical jets.

Supermassive black holes form some of the most enigmatic phenomena in astrophysics. Their enormous energy output is supposed to be generated by the...

Im Focus: A Quantum Low Pass for Photons

Physicists in Garching observe novel quantum effect that limits the number of emitted photons.

The probability to find a certain number of photons inside a laser pulse usually corresponds to a classical distribution of independent events, the so-called...

Im Focus: Microprocessors based on a layer of just three atoms

Microprocessors based on atomically thin materials hold the promise of the evolution of traditional processors as well as new applications in the field of flexible electronics. Now, a TU Wien research team led by Thomas Müller has made a breakthrough in this field as part of an ongoing research project.

Two-dimensional materials, or 2D materials for short, are extremely versatile, although – or often more precisely because – they are made up of just one or a...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Fighting drug resistant tuberculosis – InfectoGnostics meets MYCO-NET² partners in Peru

28.04.2017 | Event News

Expert meeting “Health Business Connect” will connect international medical technology companies

20.04.2017 | Event News

Wenn der Computer das Gehirn austrickst

18.04.2017 | Event News

 
Latest News

How Plants Form Their Sugar Transport Routes

28.04.2017 | Life Sciences

Protein 'spy' gains new abilities

28.04.2017 | Life Sciences

Researchers unravel the social network of immune cells

28.04.2017 | Life Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>