Navigation Links
2 brains -- 1 thought

Although no two brains are alike, they can display a comparable pattern of neural activity when exposed to similar sensory input. Scientists at the Max Planck Institute for Dynamics and Self-Organization in Göttingen have now developed a mathematical method to design networks from neural cells which exhibit a predefined pattern dynamics. The researchers hope that their method will assist them in getting closer to understanding which of the possible network configurations was privileged by evolution - and why (Physica D: Nonlinear Phenomena, December, 2006).

The nerve cells of the brain are inter-connected to a complex network. All brain activities are the result of the "firing" of nerve cells, when they send electrical pulses - like a Morse code - to other cells of the brain. This process depends on the exact dynamics of the neuronal activity. When the brain receives sensory input, calculates or remembers, it processes information encoded in a series of neuronal impulses in different nerve cells. Although no two people have the same brain, they can still share the same thought. Thus, only to a certain extent is the dynamics of neuronal activity dependent on the structure of neuronal networks. For networks far simpler than that of the human brain this idea also applies: different structures can display the same functionality. Raoul-Martin Memmesheimer and Marc Timme, researchers at the Max Planck Institute for Dynamics and Self-Organization and the Bernstein Center for Computational Neuroscience Göttingen, have developed a mathematical method to describe the set of all networks that exhibit a given dynamics. With this, they provide researchers with a tool which can be used to investigate the correlation between structure and function of a neuronal network.

A common approach in scientific research is to investigate the structure of a system in order to then draw conclusions about its function. Memmesheimer and Timme now took the reverse perspective. "For some simple networks we know the activity dynamics, that is, their function, but not their exact structure," explains Memmesheimer. "Any given dynamics can normally be created by a variety of different networks. We have developed a method to mathematically pin down this diversity." This procedure resembles juggling with many unknown quantities and requires great computational power. Already in a network of 1000 neurons (where each neuron can be connected to any other) there are a million possible contacts between any two neurons and consequently an unimaginably large number of possible networks. Each combination can have either an inhibiting or an activating effect on the downstream neuron and, in addition to this, can differ in its intensity and reaction time. The entirety of all possible networks of a defined dynamics resembles a complex figure in a multidimensional space. Here, every point on the surface specifies the data required to determine a network with the desired dynamics. Memmesheimer and Timme have now worked out a mathematical description for this figure.

The researchers examined the applicability of their model on the basis of a concrete question. They calculated all possible networks that generate a given dynamics and simultaneously fulfil a further condition: the structure of the network should be as simple as possible, that is, the number of connections and the strength of the synapses should be minimal. "Applied to a real network, one could for example analyse which structural optimisation principles function in evolution," says Timme. The dynamics of a number of very simple networks that generate repetitive patterns - like the insect walking pattern - are already well-understood. Has evolutionary pressure kept the structural complexity of such networks to a minimum - or could there have been other networks with an even simpler structure, yet possessing the same dynamics? Is it possible that many more networks fulfilling the same f unctional and structural conditions could have evolved? There is still no definite answer to these puzzles; however, with the help of the new methods developed by Memmesheimer and Timme, we are a step closer towards understanding them.
'"/>

Source:Max-Planck-Gesellschaft


Related biology news :

1. Birds brains reveal source of songs
2. Supercomputers to focus brains on AIDS dilemma
3. Mice brains shrink during winter, impairing some learning and memory
4. Divergent life history shapes gene expression in brains of salmon
5. Jumping genes contribute to the uniqueness of individual brains
6. Experts discuss use of human stem cells in ape and monkey brains
7. Sharp older brains are not the same as younger brains
8. Animal brains hard-wired to recognize predators foot movements, Queens study suggests
9. Bird brains shrink from exposure to contaminants
10. Carnegie Mellon researchers discover key deficiencies in brains of people with autism
11. Gene therapy injected into the brains of mice with Huntingtons disease

Post Your Comments:
*Name:
*Comment:
*Email:


(Date:3/30/2017)... , March 30, 2017  On April 6-7, 2017, ... the Genome hackathon at Microsoft,s headquarters in ... competition will focus on developing health and wellness apps ... Hack the Genome is the first hackathon ... The world,s largest companies in the genomics, tech and ...
(Date:3/30/2017)... NEW YORK , March 30, 2017 ... by type (physiological and behavioral), by technology (fingerprint, AFIS, ... recognition, voice recognition, and others), by end use industry ... travel and immigration, financial and banking, and others), and ... Europe , Asia Pacific ...
(Date:3/28/2017)... PUNE, India , March 28, 2017 ... (Analog, IP, Biometrics), Hardware (Camera, Monitors, Servers, Storage Devices), ... Maintenance), Vertical, and Region - Global Forecast to 2022", ... 30.37 Billion in 2016 and is projected to reach ... 15.4% between 2017 and 2022. The base year considered ...
Breaking Biology News(10 mins):
(Date:8/18/2017)... , ... August 18, 2017 , ... ... Equipment for the Semiconductor, MEMS, and Microfluidics Industries, announces the new Model 800E ... found more often in automated production mask aligners. OAI has already received ...
(Date:8/16/2017)... ... August 16, 2017 , ... ... Electrospinning and Electrospraying line of nanofiber and nanoparticle fabrication ... for the lab to fully automated pilot plants and equipment for industrial ...
(Date:8/16/2017)... MN (PRWEB) , ... August 16, 2017 , ... ... our third U.S. Food and Drug Administration (FDA) inspection at our Dilworth, MN ... No 483 was issued. This inspection was conducted as part of a routine ...
(Date:8/15/2017)... ... August 15, 2017 , ... Kapstone Medical ... years of successes helping medical technology companies and inventors develop and safeguard their latest ... full-service national engineering firm with a portfolio of clients in the United States and ...
Breaking Biology Technology: