Animals and humans find their way through the world using an internally generated navigation system. In mammals, components of this navigational system are the hippocampus and the entorhinal cortex.
A grid-like network of nerve cells in the brain (left, and top right) shows a similar hexagonal organization (right, bottom) to the mental map formed by the nerve cells in the brain. Science
These structures memorize and represent our environment in form of a cognitive map, which is a mental representation of space. The representation of space in the entorhinal cortex is particularly fascinating—here, nerve cells discharge in a grid like pattern across space when the animal is moving.
It is thought that this so-called grid cell activity works much like the grid lines on a map providing mammals with a metric for space. So far, it has been unclear how such grid patterns of activated nerve cells are anatomically formed in the brain.
Now, a research team headed by Leibniz prize winner Professor Michael Brecht from the Humboldt-Universität in Berlin, the Cluster of Excellence Neurocure, and the Bernstein Center Berlin has discovered a grid-like network of nerve cells in the entorhinal cortex. By using a protein that binds to calcium in selected nerve cells, the scientists visualized a small circuit of nerve cells. The dendrites of these neurons formed a hexagonal pattern in space that had a striking resemblance to the known grid patterns. Moreover, the neurons in this network showed the same characteristic activity rhythm as the grid cells, when the researchers measured the nerve cell activity in moving animals.
“People have known that the brain divides places into grids, much like we draw lines on a map. However, what was not known is what causes the brain to do it. What we have shown here is the existence of a circuit in the brain, which physically looks like the spatial activity pattern of the so-called grid cells. This makes us think that this circuit structure might be the underlying cause of this representation”, Brecht comments on the study that has been published in the renowned scientific journal Science this Thursday.
Hence, the discovery of the neural network might help us to understand how the brain generates grid lines on our mental maps and how we mentally measure distances. The scientists also hope to gain insight into how the brain forms spatial memories—a brain function which is disturbed or lost in many neurodegenerative diseases such as dementia. On a more fundamental level, how the brain forms spatial memories may be related to how we form memories in general: as in the memory palaces of the ancient Greeks, objects could be linked with places to serve as a mnemonic device.
The Bernstein Center Berlin is part of the National Bernstein Network Computational Neuroscience in Germany. With this funding initiative, the German Federal Ministry of Education and Research (BMBF) has supported the new discipline of Computational Neuroscience since 2004 with over 170 million Euros. The network is named after the German physiologist Julius Bernstein (1835-1917).Contact:
Weitere Informationen:http://www.activetouch.de Lab of Michael Brecht
Mareike Kardinal | idw
Molecular Spies to Fight Cancer - Procedure for improving tumor diagnosis successfully tested
03.08.2015 | Helmholtz-Zentrum Dresden-Rossendorf
Stroke: news about platelets
03.08.2015 | Julius-Maximilians-Universität Würzburg
Glacier decline in the first decade of the 21st century has reached a historical record, since the onset of direct observations. Glacier melt is a global phenomenon and will continue even without further climate change. This is shown in the latest study by the World Glacier Monitoring Service under the lead of the University of Zurich, Switzerland.
The World Glacier Monitoring Service, domiciled at the University of Zurich, has compiled worldwide data on glacier changes for more than 120 years. Together...
Using ultracold atoms trapped in light crystals, scientists from the MPQ, LMU, and the Weizmann Institute observe a novel state of matter that never thermalizes.
What happens if one mixes cold and hot water? After some initial dynamics, one is left with lukewarm water—the system has thermalized to a new thermal...
Physicists from Regensburg and Marburg, Germany have succeeded in taking a slow-motion movie of speeding electrons in a solid driven by a strong light wave. In the process, they have unraveled a novel quantum phenomenon, which will be reported in the forthcoming edition of Nature.
The advent of ever faster electronics featuring clock rates up to the multiple-gigahertz range has revolutionized our day-to-day life. Researchers and...
Researchers have developed an ultrafast light-emitting device that can flip on and off 90 billion times a second and could form the basis of optical computing.
Joint BioEnergy Institute study identifies bacterial protein that is key to protecting rice against bacterial blight
A bacterial signal that when recognized by rice plants enables the plants to resist a devastating blight disease has been identified by a multi-national team...
23.07.2015 | Event News
10.07.2015 | Event News
25.06.2015 | Event News
03.08.2015 | Materials Sciences
03.08.2015 | Life Sciences
03.08.2015 | Life Sciences