- Poster presentation
- Open Access
Neuronal avalanches and the cortico-striatal network
© Belić et al; licensee BioMed Central Ltd. 2012
Published: 16 July 2012
Neuronal avalanches are spontaneous activity cascades observed in superficial cortical layers with statistical properties expected from the network operating near a critical point . In such a network, neuronal activity on one active site triggers, on average, similar activity at other site and therefore the overall activity does not increase or die out over time. Neuronal avalanches have been found in vitro  and in vivo , and display long-term stability, diversity, and fast propagation of local synchrony. They characterize networks that have a maximum dynamic range  and might play a central role in information transmission  and storage . Their activity is characterized by brief bursts lasting tens of milliseconds, separated by periods of quiescence lasting several seconds and when observed with multi-electrode arrays, the number of electrodes activated is well described by a power law with exponent close to -1.5 .
Here we study neuronal avalanches in an open-loop system of cortex and striatum. The striatum is the main input structure of the basal ganglia and plays an important role in motor and cognitive functions. Understanding how the striatum responds to cortical inputs has crucial importance for clarifying the overall functions of the basal ganglia. The projection neurons of the striatum have a high threshold for activation and receive excitatory input from different regions of the cerebral cortex. Although the striatum contains several distinct cell types, 90-95% are GABAergic medium spiny projection neurons (MSNs). These cells are major targets of cortical inputs, the recurrent connection among them mediate weak feedback inhibition and neighboring MSNs are not likely to share cortical inputs . Fast-spiking interneurons are relatively sparse elements of striatal networks. They project extensively to nearby MSNs and provide strong feedforward inhibition and seem to be critical nodes governing striatal output .
Preliminary experiments indicate that activity bursts in the striatum do not follow a power law with characteristic exponent of -1.5. Here we developed an abstract model of the cortico-striatal network that reproduces statistics observed in experimental data. We discuss which kind of connectivity between cortex and striatum, as well as connectivity and strength of inhibition within striatum can lead to results that are in line with experimental data.
Supported by the Erasmus Mundus Joint Doctoral program EuroSPIN.
- Beggs J, Plenz D: Neural avalanches in neocortical circuits. The Journal of Neuroscience. 2003, 23: 11167-11177.PubMedGoogle Scholar
- Gireesh ED, Plenz D: Neural avalanches organize as nested theta and beta/gamma-oscillations during development of cortical layer 2/3. PNAS. 2008, 105: 7576-7581. 10.1073/pnas.0800537105.PubMed CentralView ArticlePubMedGoogle Scholar
- Shew W, Yang H, Petermann T, Roy R, Plenz D: Neural avalanches imply maximum dynamic range in cortical networks at criticality. The Journal of Neuroscience. 2009, 29: 15595-15600. 10.1523/JNEUROSCI.3864-09.2009.PubMed CentralView ArticlePubMedGoogle Scholar
- Beggs J, Plenz D: Neural avalanches are diverse and precise activity patterns that are stable for many hours in cortical slice cultures. The Journal of Neuroscience. 2004, 24: 5216-5229. 10.1523/JNEUROSCI.0540-04.2004.View ArticlePubMedGoogle Scholar
- Klaus A, Yu S, Plenz D: Statistical analyses support power law distributions found in neuronal avalanches. PLoS ONE. 2011, 6 (5): e19779-10.1371/journal.pone.0019779.PubMed CentralView ArticlePubMedGoogle Scholar
- Zheng J, Wilson CJ: Corticostriatalcombinatorics: the implication of corticostriatal axonal arborizations. Journal of Neurophysiology. 2002, 87: 1007-1017.PubMedGoogle Scholar
- Berke J: Functional properties of striatal fast-spiking interneurons. Frontiers in Systems Neuroscience. 2011, 5: 1-7.View ArticleGoogle Scholar
This article is published under license to BioMed Central Ltd. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.