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More than 80 billion nerve cells – and every single one of them is in contact with up to 10,000 other cells. The human brain is an extremely complex network, not to mention a dynamic one, for it changes continuously during the course of our life.
Where do we think and feel?
We have long known where the language centre is located, and where visual and acoustic stimuli are processed. Even the location of individual thoughts and feelings can be pinpointed. Our “map” of the brain has become increasingly detailed ever since technologies such as functional magnetic resonance imaging (fMRI) have been used to measure the brain’s activities with great precision.
How do we think and feel?
But how does perception come about in the brain cells? Which rules does the transmission of electrical impulses in the cell networks follow, allowing us to react precisely and quickly? And how do memories form? To unlock these secrets of the brain, neuroscientists at the Max Planck Institute for Brain Research in Frankfurt am Main are concentrating on the tiniest entities: individual nerve cells and the ways in which they are interconnected. “Methods such as fMRI reveal to us where a particular brain function takes place. We ask: how does it take place?”, says Professor Erin Schuman, who came to Frankfurt from the California Institute of Technology in 2009 to serve as one of the institute’s three directors.
Proteins for memory
Schuman’s research group is studying the synapses, the links between the individual nerve cells. “These connections can be strengthened or weakened and that is one way in which memory is stored”, explains the neuroscientist. Proteins play an important role here: they are produced in the nerve cell and made available at the right place and at the right time. For Erin Schuman, the fascinating question is how this mechanism is able to burn experiences into our memories for a lifetime, despite the proteins themselves disintegrating again after just a few days.
Mathematical modelling of the brain
A different approach is followed by the scientists collaborating in the nationwide Bernstein Network Computational Neuroscience. Mathematicians, physicists, biologists, psychologists, doctors and engineers in this network conduct experiments to study how our brains process data, and create computer models of these processes. They hope to discover the general principles according to which the brain is organized and functions.
From basic research to application
The questions that the scientists are raising concern the fundamental mechanisms upon which the brain’s functions are based. Their answers will also be beneficial for medicine, allowing us for example to better understand conditions such as autism. “Processes by which proteins are made, transported and degraded in brain cells are at the nexus of neural disorders”, explains Erin Schuman. However, neuroscientists also want to learn how this “biological computer” functions so that computers can be made even faster and more efficient. If they succeed, this will also benefit brain research.
Max Planck Institute for Brain Research
No other organ is as complex as the human brain – each of the 100 billion or so nerve cells can link up with up to 10,000 other nerve cells. The Max Planck Institute for Brain Research is dedicated to the study of this super-organ, and endeavors to unlock its secrets in the process. The scientific focus of the Institute is on circuits, or networks of interacting parts, including molecules in a neuron, neurons in a local circuit and circuit-to-circuit communication. Experimental work at the Institute is carried out on non-primate animal species (rodents, fish, reptiles and cephalopods) .The researchers measure how the nerve systems process sensory input, how these experiences are stored, and what response behavior results. Part of their work focuses on decoding the circuits in the brain and the specific contacts between nerve cells (synapses). The studies apply molecular biological, imaging, genetic and electrophysiological methods as well as computer models.
www.brain.mpg.de