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 Researchers release the brakes on the immune system
18.10.2017 | Rheinische Friedrich-Wilhelms-Universität Bonn

nachricht Norovirus evades immune system by hiding out in rare gut cells
12.10.2017 | University of Pennsylvania School of Medicine

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: Neutron star merger directly observed for the first time

University of Maryland researchers contribute to historic detection of gravitational waves and light created by event

On August 17, 2017, at 12:41:04 UTC, scientists made the first direct observation of a merger between two neutron stars--the dense, collapsed cores that remain...

Im Focus: Breaking: the first light from two neutron stars merging

Seven new papers describe the first-ever detection of light from a gravitational wave source. The event, caused by two neutron stars colliding and merging together, was dubbed GW170817 because it sent ripples through space-time that reached Earth on 2017 August 17. Around the world, hundreds of excited astronomers mobilized quickly and were able to observe the event using numerous telescopes, providing a wealth of new data.

Previous detections of gravitational waves have all involved the merger of two black holes, a feat that won the 2017 Nobel Prize in Physics earlier this month....

Im Focus: Smart sensors for efficient processes

Material defects in end products can quickly result in failures in many areas of industry, and have a massive impact on the safe use of their products. This is why, in the field of quality assurance, intelligent, nondestructive sensor systems play a key role. They allow testing components and parts in a rapid and cost-efficient manner without destroying the actual product or changing its surface. Experts from the Fraunhofer IZFP in Saarbrücken will be presenting two exhibits at the Blechexpo in Stuttgart from 7–10 November 2017 that allow fast, reliable, and automated characterization of materials and detection of defects (Hall 5, Booth 5306).

When quality testing uses time-consuming destructive test methods, it can result in enormous costs due to damaging or destroying the products. And given that...

Im Focus: Cold molecules on collision course

Using a new cooling technique MPQ scientists succeed at observing collisions in a dense beam of cold and slow dipolar molecules.

How do chemical reactions proceed at extremely low temperatures? The answer requires the investigation of molecular samples that are cold, dense, and slow at...

Im Focus: Shrinking the proton again!

Scientists from the Max Planck Institute of Quantum Optics, using high precision laser spectroscopy of atomic hydrogen, confirm the surprisingly small value of the proton radius determined from muonic hydrogen.

It was one of the breakthroughs of the year 2010: Laser spectroscopy of muonic hydrogen resulted in a value for the proton charge radius that was significantly...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

ASEAN Member States discuss the future role of renewable energy

17.10.2017 | Event News

World Health Summit 2017: International experts set the course for the future of Global Health

10.10.2017 | Event News

Climate Engineering Conference 2017 Opens in Berlin

10.10.2017 | Event News

 
Latest News

Terahertz spectroscopy goes nano

20.10.2017 | Information Technology

Strange but true: Turning a material upside down can sometimes make it softer

20.10.2017 | Materials Sciences

NRL clarifies valley polarization for electronic and optoelectronic technologies

20.10.2017 | Interdisciplinary Research

VideoLinks
B2B-VideoLinks
More VideoLinks >>>