A novel theoretical framework for mathematically modeling nerve cells has illuminated for the first time how small synaptic impulses enable non-linear information processing in the brain. Reported in PLoS Computational Biology, the findings offer fundamental insights relevant to a wide range of biological, physical and technical systems.
In the field of neuroscience, neurons are known to communicate via so-called gaction potentialsh, brief impulses which cause a cellfs membrane potential to rise and fall. Only when many such impulses together exceed a threshold value does the neuron gfireh, releasing its action potential to target neurons. How neurons transfer action potentials from inputs into outputs determines which elementary operations they are able to perform, and at what rate.
With their latest work, researchers at the RIKEN Brain Science Institute and Bernstein Center for Computational Neuroscience set out to resolve contradictory findings uncovered earlier regarding this input-output relationship. At issue was the conventional theory of spiking neuronal networks, which approximates impulses in the limit where they become vanishingly tiny and infinitely numerous, limiting the capabilities of individual neurons to simple addition of inputs.
Using a newly-developed high-precision method for simulating nonlinear neuron models (see references), the team had previously uncovered contradictions in this theory. To unravel this mystery, the researchers developed a new analytic framework which explicitly incorporates the finite effect of each input at the critical boundary near the firing threshold. With this change, they show that not only can neurons process information far faster than previously believed, they can also perform nonlinear operations such as multiplication that are key to complex information processing.
While more accurately capturing the network aspect of neural dynamics, the new framework also reveals how cooperation between seemingly uncoordinated input signals enables neurons to perform many non-linear operations at the same time. Future work will build on these findings toward a better understanding of brain function, a fundamental requirement for treating neural diseases.
For more information, please contact:
Hanuschkin A, Kunkel S, Helias M, Morrison A and Diesmann M (2010). A general and efficient method for incorporating precise spike times in globally time-driven simulations. Front. Neuroinform. 4:113. doi:10.3389/fninf.2010.00113The simulation software is freely available from the NEST Initiative: http://www.nest-initiative.org
20.11.2017 | Washington University in St. Louis
Carefully crafted light pulses control neuron activity
20.11.2017 | University of Illinois at Urbana-Champaign
The formation of stars in distant galaxies is still largely unexplored. For the first time, astron-omers at the University of Geneva have now been able to closely observe a star system six billion light-years away. In doing so, they are confirming earlier simulations made by the University of Zurich. One special effect is made possible by the multiple reflections of images that run through the cosmos like a snake.
Today, astronomers have a pretty accurate idea of how stars were formed in the recent cosmic past. But do these laws also apply to older galaxies? For around a...
Just because someone is smart and well-motivated doesn't mean he or she can learn the visual skills needed to excel at tasks like matching fingerprints, interpreting medical X-rays, keeping track of aircraft on radar displays or forensic face matching.
That is the implication of a new study which shows for the first time that there is a broad range of differences in people's visual ability and that these...
Computer Tomography (CT) is a standard procedure in hospitals, but so far, the technology has not been suitable for imaging extremely small objects. In PNAS, a team from the Technical University of Munich (TUM) describes a Nano-CT device that creates three-dimensional x-ray images at resolutions up to 100 nanometers. The first test application: Together with colleagues from the University of Kassel and Helmholtz-Zentrum Geesthacht the researchers analyzed the locomotory system of a velvet worm.
During a CT analysis, the object under investigation is x-rayed and a detector measures the respective amount of radiation absorbed from various angles....
The quantum world is fragile; error correction codes are needed to protect the information stored in a quantum object from the deteriorating effects of noise. Quantum physicists in Innsbruck have developed a protocol to pass quantum information between differently encoded building blocks of a future quantum computer, such as processors and memories. Scientists may use this protocol in the future to build a data bus for quantum computers. The researchers have published their work in the journal Nature Communications.
Future quantum computers will be able to solve problems where conventional computers fail today. We are still far away from any large-scale implementation,...
Pillared graphene would transfer heat better if the theoretical material had a few asymmetric junctions that caused wrinkles, according to Rice University...
15.11.2017 | Event News
15.11.2017 | Event News
30.10.2017 | Event News
20.11.2017 | Earth Sciences
20.11.2017 | Earth Sciences
20.11.2017 | Life Sciences