Neuroscientists at the German Primate Center show how nerve cells communicate with each other in neural networks
Thinking, feeling, acting - our brain is the control center in the head that steers everything we do. A network of about 100 billion nerve cells linked together by around 100 trillion synapses provides the basis for these mechanisms.
Neuroscientists at the German Primate Center (DPZ) – Leibniz Institute for Primate Research examined for the first time how this neural network is organized and how the flow of information between different brain areas is coordinated at the level of individual nerve cells.
Through studies with rhesus monkeys, they have found that the nerve cells in the different brain areas that control our hand movements strongly interact with each other and are organized in cross-area functional groups. They also showed that a few neurons control the network by acting as central nodes (hubs) and coordinate the flow of information within the nerve cell network. These hubs also greatly communicate with each other (rich-club) and thus form an area-spanning backbone for communication.
Interestingly, the type of communication between hubs differs from that of the remaining network. Information processing through hubs is characterized by their rhythmic activity that is synchronized to one another. This suggests that large groups of neurons synchronize rhythmically to connect parts of the brain together in order to solve specific tasks (eLife, 2016).
The performances of our brain like thinking, remembering, perceiving and motion control can only arise through the interaction of the network of nerve cells. It is the subject of numerous research projects to examine how this network is structured. Through graph theoretical approaches and brain studies like electroencephalography (EEG) or functional magnetic resonance imaging (fMRI), it has been known for some time that various regions of the brain are organized as a complex network, which enables fast and fault-resistant information processing. Using these methods, it is not possible to measure the activity of individual nerve cells. However, this is necessary to understand how such neural diseases like schizophrenia and autism arise.
Studies on nerve cell level
“In our study, we want to find out how the network of individual nerve cells is organized through several brain areas”, says Benjamin Dann, PhD student in the Neurobiology Laboratory at the German Primate Center and lead author of the study. “We also wanted to know exactly how the flow of information between nerve cells of different brain areas is coordinated.” For this, three rhesus monkeys were trained to repeatedly execute a grasping task. During the task, the activity of nerve cells in three different areas of the brain, the anterior intraparietal cortex (AIP), the premotor cortex (F5), and the primary motor cortex (M1) was measured by so-called microelectrode arrays. These brain regions form a neural network that controls the planning and execution of hand movements.
Nerve cells in the rich-club fire rhythmically
The scientists found that the nerve cells of all three brain areas form a strong interconnected network, which is organized in turn into functional subunits (modules). Surprisingly, these modules do not correspond to the three considered brain areas. 84 percent of the modules were not limited to one area, but also included nerve cells of the other two areas. Moreover, they could show that there are individual neurons within the network, which play a central role. “These nodes or hubs have disproportionately more connections on the network than the other nerve cells”, Benjamin Dann explains. “In addition, they are highly interconnected and form a so-called rich-club at the cellular level, which can be used to coordinate the information routing in the network.”
Furthermore, the scientists observed that the nerve cells are rhythmically active in the rich-club and also communicate with the rest of the network rhythmically. The other nerve cells, however, are mainly arrhythmicly active. “We were the first to show that the rhythmic activity in fixed frequencies is an important feature of the central hub and rich-club cells that coordinate the information flow”, Benjamin Dann summarizes his results. “We assume that rhythmic synchrony of neurons is a key mechanism for fast and robust communication throughout the brain. Thus, even distant groups of neurons can be functionally connected to perform certain thoughts or actions.”
The study may contribute in the future to a better understanding of neuronal diseases such as schizophrenia and autism that are affected by interference from rhythmic synchrony and alterations in the network structure. Accurate knowledge of these processes in the brain is important in order to develop new therapies.
Dann, B., Michaels, J., Schaffelhofer, S., Scherberger H. (2016): Uniting functional network topology and oscillations in the fronto-parietal single unit network of behaving primates. eLife, DOI: http://dx.doi.org/10.7554/eLife.15719
Contact and notes for editors
Phone: +49 551 3851-484
Prof. Dr. Hansjörg Scherberger
Phone: +49 551 3851-494
Dr. Sylvia Siersleben (Communication)
Phone: +49 551 3851-163
Printable pictures and captions are available in our media library. This press release with additional information is also to be found on our website. Please send us a copy or link in case of publication.
The German Primate Center (DPZ) – Leibniz Institute for Primate Research conducts biological and biomedical research on and with primates in the fields of infection research, neuroscience and primate biology. In addition, it operates four field stations in the tropics and is a reference and service center for all aspects of primate research. The DPZ is one of the 88 research and infrastructure institutes of the Leibniz Association in Germany.
http://www.dpz.eu - Homepage German Primate Center
http://www.dpz.eu/en/home/single-view/news/nervenzellen-mit-rhythmusgefuehl-1.ht... - Press release with further information
http://medien.dpz.eu/webgate/keyword.html?currentContainerId=3481 - Media library with prinable pictures
Dr. Susanne Diederich | idw - Informationsdienst Wissenschaft
Fine organic particles in the atmosphere are more often solid glass beads than liquid oil droplets
21.04.2017 | Max-Planck-Institut für Chemie
Study overturns seminal research about the developing nervous system
21.04.2017 | University of California - Los Angeles Health Sciences
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...
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...
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...
Two researchers at Heidelberg University have developed a model system that enables a better understanding of the processes in a quantum-physical experiment...
Glaciers might seem rather inhospitable environments. However, they are home to a diverse and vibrant microbial community. It’s becoming increasingly clear that they play a bigger role in the carbon cycle than previously thought.
A new study, now published in the journal Nature Geoscience, shows how microbial communities in melting glaciers contribute to the Earth’s carbon cycle, a...
20.04.2017 | Event News
18.04.2017 | Event News
03.04.2017 | Event News
21.04.2017 | Physics and Astronomy
21.04.2017 | Health and Medicine
21.04.2017 | Physics and Astronomy