58 research outputs found
The geometry of spontaneous spiking in neuronal networks
The mathematical theory of pattern formation in electrically coupled networks
of excitable neurons forced by small noise is presented in this work. Using the
Freidlin-Wentzell large deviation theory for randomly perturbed dynamical
systems and the elements of the algebraic graph theory, we identify and analyze
the main regimes in the network dynamics in terms of the key control
parameters: excitability, coupling strength, and network topology. The analysis
reveals the geometry of spontaneous dynamics in electrically coupled network.
Specifically, we show that the location of the minima of a certain continuous
function on the surface of the unit n-cube encodes the most likely activity
patterns generated by the network. By studying how the minima of this function
evolve under the variation of the coupling strength, we describe the principal
transformations in the network dynamics. The minimization problem is also used
for the quantitative description of the main dynamical regimes and transitions
between them. In particular, for the weak and strong coupling regimes, we
present asymptotic formulas for the network activity rate as a function of the
coupling strength and the degree of the network. The variational analysis is
complemented by the stability analysis of the synchronous state in the strong
coupling regime. The stability estimates reveal the contribution of the network
connectivity and the properties of the cycle subspace associated with the graph
of the network to its synchronization properties. This work is motivated by the
experimental and modeling studies of the ensemble of neurons in the Locus
Coeruleus, a nucleus in the brainstem involved in the regulation of cognitive
performance and behavior
Osteogenic differentiation of adipose tissue-derived mesenchymal stem cells cultured with different concentrations of prolactin
Adaptation of Stem Cells to 96‐Well Plate Assays: Use of Human Embryonic and Mouse Neural Stem Cells in the MTT Assay
Oestradiol Potentiates the Effects of Certain Pyrethroid Compounds in the MCF7 Human Breast Carcinoma Cell Line
Monoclonal Antibodies that bind to Hemopoietic Stem Cells. Characterization and Immunohistochemical Localization of Cells Expressing gp50-65.
Plasma membrane electron transport in leukemia cells: a new potential target for anticancer drug development
A new potential target for antileukemic drugs could be represented by trans-plasma membrane electron transport
Diallyl sulfide depletes the inositol trisphosphate-sensitive intracellular Ca2+ stores and activates SOC-channels in HL-60 human cells
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