QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

HOME  |   SEARCH  |   ARCHIVE  |   SUBSCRIBE  |   CONTACT  |   HELP

The Journal of Neuroscience, February 11, 2009, 29(6):1677-1687; doi:10.1523/JNEUROSCI.5218-08.2009

This Article Full Text Full Text (PDF) Supplemental Data Submit an eLetter Alert me when this article is cited Alert me when eLetters are posted Alert me if a correction is posted Citation Map Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via Google Scholar Google Scholar Articles by Bogaard, A. Articles by Booth, V. Search for Related Content PubMed PubMed Citation Articles by Bogaard, A. Articles by Booth, V.

 Previous Article  |  Next Article 

Neurobiology of Disease
Interaction of Cellular and Network Mechanisms in Spatiotemporal Pattern Formation in Neuronal Networks

Andrew Bogaard,¹ Jack Parent,⁴ Michal Zochowski,^1,5,6,7 * and Victoria Booth^2,3,6 *

Departments of ¹Physics, ²Mathematics, ³Anesthesiology, and ⁴Neurology, ⁵Biophysics Research Division, ⁶Neuroscience Graduate Program, and ⁷Michigan Center for Theoretical Physics, University of Michigan, Ann Arbor, Michigan 48109

Correspondence should be addressed to Michal Zochowski, Department of Physics, University of Michigan, 450 Church Street, Ann Arbor, MI 48109. Email: michalz{at}umich.edu

Spatiotemporal patterning of neuronal activity is considered to be an important feature of cognitive processing in the brain as well as pathological brain states, such as seizures. Here, we investigate complex interactions between intrinsic properties of neurons and network structure in the generation of network spatiotemporal patterning in the context of seizure-like synchrony. We show that membrane excitability properties have differential effects on network activity patterning for different network topologies. We consider excitatory networks consisting of neurons with excitability properties varying between type I and type II that exhibit significantly different spike frequency responses to external current stimulation, especially at firing threshold. We find that networks with type II-like neurons show higher synchronization and bursting capacity across a range of network topologies than corresponding networks with type I-like neurons. These differences in activity patterning are persistent across different network sizes, connectivity strengths, magnitudes of random external input, and the addition of inhibitory interneurons to the network, making them highly likely to be relevant to brain function. Furthermore, we show that heterogeneous networks of mixed cell types show emergent dynamical patterns even for very low mixing ratios. Specifically, the addition of a small percentage of type II-like cells into a network of type I-like cells can markedly change the patterning of network activity. These findings suggest that cellular as well as network mechanisms can go hand in hand, leading to the generation of seizure-like discharges, suggesting that a single ictogenic mechanism alone may not be responsible for seizure generation.

Key words: network structure; spatiotemporal pattern formation; synchrony; network dynamics; ictogenesis; cellular excitability

---

Received Oct. 29, 2008; revised Jan. 5, 2009; accepted Jan. 6, 2009.

Correspondence should be addressed to Michal Zochowski, Department of Physics, University of Michigan, 450 Church Street, Ann Arbor, MI 48109. Email: michalz{at}umich.edu

Home  |   Search  |   Archive  |   Subscribe  |   Contact  |   Help