Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Researchers find speedometer in the brain

05.06.2015

Cover story in the journal “Neuron”: Newly discovered nerve cells trigger locomotion and deliver information on movement velocity to the spatial memory systems

Researchers in Bonn have identified neural circuits in the brains of mice that are pivotal for movement and navigation in space. These nerve cells that are presumed to exist in a similar form in humans, give the start signal for locomotion and also supply the brain with speed-related information.


Researchers in Bonn have identified neural circuits in the brains of mice that are pivotal for movement and navigation in space. These nerve cells that are presumed to exist in a similar form in humans, give the start signal for locomotion and also supply the brain with speed-related information. Source: DZNE / Falko Fuhrmann

Scientists at the German Center for Neurodegenerative Diseases (DZNE) and the University of Bonn led by Prof. Stefan Remy report on this in the journal “Neuron”. Their investigations give new insights into the workings of spatial memory. Furthermore, they could also help improve our understanding of movement related symptoms associated with Parkinson’s disease.

In a familiar environment our movements are purposeful. For example, if we leave our office desk for a coffee break, we naturally follow a predefined route that has been stored in our memory: Through the office door, left into the hall, past the windows. To keep us on track, our brain has to process varying sensory impressions quickly. “This is a fundamental issue our brain has to deal with.

Not just on our way to the coffee machine, but any time we move in space. For example when we are on a bike or in a car,” explains Remy. With increasing speed, the data rate also increases, he emphasizes: “The faster we move, the less time the brain has to take in environmental cues and to associate them with a location on our memorized spatial map. Our perception therefore has to keep pace with the speed of movement so that we remember the right way to go. Otherwise we end up at the copy machine instead of the coffee machine.”

Rhythmic fluctuations

It has been known for some time that the hippocampus - the part of the brain that controls memory, particularly spatial memory - adjusts to the speed of locomotion. “The electrical activity of the hippocampus undergoes rhythmic fluctuations. The faster we move, the faster certain nerve cells are activated,” says Remy. “This increased activation rate sensitizes the brain. It becomes more receptive to the changing sensory impressions that have to be processed when moving.”

But how does the brain actually know how fast a movement is? Previously there was no answer to this question. Now, Remy and his colleagues have decoded the mechanism. For this, they stimulated specific areas within the mouse brain and recorded the ensuing brain activity and the mice’s locomotion. “We have identified the neural circuits in mice that link their spatial memory to the speed of their movement. This interplay is an important foundation for a functioning spatial memory,” says Remy. “We assume that humans have similar nerve cells, as the brains of mice and humans have a very similar structure in these regions.”

Small cell group

The cells in question are located in the “medial septum”, a part of the brain directly connected to the hippocampus. They make up a relatively small group comprising a few thousand cells. “They gather information from sensory and locomotor systems, determine the speed of movement and transmit this information to the hippocampus. In this way, they tune the spatial memory systems for optimized processing of sensory stimuli during locomotion,” explains Remy. However, these circuits have even more functions. “We have found that they also give the start signal for locomotion and that they actively control its speed. Until now, this control function was almost exclusively ascribed to the motor cerebral cortex.”

These newly discovered nerve cells are linked with areas of the brain that are affected by Parkinson’s in humans. This disease is associated with movement-related symptoms and can cause dementia. “In this respect, our results go beyond the workings of spatial memory; they also have the potential to provide new insights into how memory systems and the execution of movements are affected in Parkinson’s disease,” says Remy.

Original publication
„Locomotion, Theta Oscillations, and the Speed-Correlated Firing of Hippocampal Neurons Are Controlled by a Medial Septal Glutamatergic Circuit”, Falko Fuhrmann, Daniel Justus, Liudmila Sosulina, Hiroshi Kaneko,Tatjana Beutel, Detlef Friedrichs, Susanne Schoch, Martin Karl Schwarz, Martin Fuhrmann, Stefan Remy, Neuron 2015, doi: 10.1016/j.neuron.2015.05.001

Video-Abstract
https://www.youtube.com/watch?v=Q8BGehgXK94

The German Center for Neurodegenerative Diseases (DZNE) investigates the causes of diseases of the nervous system and develops strategies for prevention, treatment and care. It is an institution of the Helmholtz Association of German Research Centres with sites in Berlin, Bonn, Dresden, Göttingen, Magdeburg, Munich, Rostock/Greifswald, Tübingen and Witten. The DZNE cooperates closely with universities, their clinics and other research facilities.

http://www.dzne.de
http://www.twitter.com/dzne_en
http://www.dzne.de/facebook

Weitere Informationen:

http://www.dzne.de/en/about-us/public-relations/meldungen/2015/press-release-no-...

Dr. Marcus Neitzert | idw - Informationsdienst Wissenschaft

More articles from Health and Medicine:

nachricht Routing gene therapy directly into the brain
07.12.2017 | Boston Children's Hospital

nachricht New Hope for Cancer Therapies: Targeted Monitoring may help Improve Tumor Treatment
01.12.2017 | Berliner Institut für Gesundheitsforschung / Berlin Institute of Health (BIH)

All articles from Health and Medicine >>>

The most recent press releases about innovation >>>

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

Im Focus: Scientists channel graphene to understand filtration and ion transport into cells

Tiny pores at a cell's entryway act as miniature bouncers, letting in some electrically charged atoms--ions--but blocking others. Operating as exquisitely sensitive filters, these "ion channels" play a critical role in biological functions such as muscle contraction and the firing of brain cells.

To rapidly transport the right ions through the cell membrane, the tiny channels rely on a complex interplay between the ions and surrounding molecules,...

Im Focus: Towards data storage at the single molecule level

The miniaturization of the current technology of storage media is hindered by fundamental limits of quantum mechanics. A new approach consists in using so-called spin-crossover molecules as the smallest possible storage unit. Similar to normal hard drives, these special molecules can save information via their magnetic state. A research team from Kiel University has now managed to successfully place a new class of spin-crossover molecules onto a surface and to improve the molecule’s storage capacity. The storage density of conventional hard drives could therefore theoretically be increased by more than one hundred fold. The study has been published in the scientific journal Nano Letters.

Over the past few years, the building blocks of storage media have gotten ever smaller. But further miniaturization of the current technology is hindered by...

Im Focus: Successful Mechanical Testing of Nanowires

With innovative experiments, researchers at the Helmholtz-Zentrums Geesthacht and the Technical University Hamburg unravel why tiny metallic structures are extremely strong

Light-weight and simultaneously strong – porous metallic nanomaterials promise interesting applications as, for instance, for future aeroplanes with enhanced...

Im Focus: Virtual Reality for Bacteria

An interdisciplinary group of researchers interfaced individual bacteria with a computer to build a hybrid bio-digital circuit - Study published in Nature Communications

Scientists at the Institute of Science and Technology Austria (IST Austria) have managed to control the behavior of individual bacteria by connecting them to a...

Im Focus: A space-time sensor for light-matter interactions

Physicists in the Laboratory for Attosecond Physics (run jointly by LMU Munich and the Max Planck Institute for Quantum Optics) have developed an attosecond electron microscope that allows them to visualize the dispersion of light in time and space, and observe the motions of electrons in atoms.

The most basic of all physical interactions in nature is that between light and matter. This interaction takes place in attosecond times (i.e. billionths of a...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

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

AKL’18: The opportunities and challenges of digitalization in the laser industry

07.12.2017 | Event News

 
Latest News

Using drones to estimate crop damage by wild boars

12.12.2017 | Ecology, The Environment and Conservation

How fires are changing the tundra’s face

12.12.2017 | Ecology, The Environment and Conservation

Telescopes team up to study giant galaxy

12.12.2017 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>