ISSN 0869-6632 (Print)
ISSN 2542-1905 (Online)

Нелинейная динамика и нейронаука

Calcium oscillations in astrocytes part 2 dynamics of interacting calcium oscillators

We investigated bifurcation mechanisms of oscillatory dynamics of interacting chemically excitable cells (astrocytes). In model of three interacting astrocytes we studied bifurcation transitions leading to generation of calcium oscillations induced by the intercellular di?usion. We analyzed basic mechanisms of limit cycle instabilities and destructions, typical transitions to chaotic oscillations and basic properties of intercellular synchronization.

Subjective evaluation of semantically unlike objects during exchange transactions

The work is devoted to quantitative modelling of regularities in the subjective comparison of the significance of unlike material and mental objects which are of a substantial value for a man. It is assumed that each object is perceived by a man as a complex semantic stimulus characterized by subjective significance and a finite set of the features which are to be taken into account.

Activity synchronization of different neuron types in the columns of the cerebral visual cortex

The results of neurophysiological and modeling studies focused on activity synchronization among of different types of neurons and spike shape dynamics in two bistability transition states have been presented. In modeling study, spike duration range of «fast» or «slow» neurons recorded in neurophysiological experiments were simulated.

Cognitive neurodynamics two strategies navigation behavior of organisms

The conceptual model and computer simulations results of path integration in free­scalable nonlinear oscillator neural networks with even cyclic inhibition (ECI­networks) are discussed in this paper. To estimate the phase shifting under input impact the ECI­networks contain two subsystems namely reference and information ones. The population of reference (nonencoding) oscillatory units has significant role in generation and stabilization of numerous time scales despite it don’t assist directly in the phase pattern encoding of input signals.

Fractal analysis of neuron’s activity and model’s behavior

It is shown that discovered fractal properties of neuronal interspike interval sequence contradicts the reflex theory. The simplified model of formation and realization of individual experience based on reflex theory view of individual experience structure as a tree has been proposed. Behavior of the model does not show fractal properties. It is suggested that non­reflex model of individual experience structure formed as a tree of skills is needed. It is shown the possibility of nonlinear (fractal) properties estimation in the data for evaluation of a theory.

Simulator of the dynamic processes of sensor signal processing in talamo­cortical networks

Now models (simulators) of neural networks are actively developed. Their architecture and design are based on features of structure and principles of work of real neurons and neurobiological systems. Working out neurolike models based on the data about architecture of connections in a brain, it is aimed at finding­out of principles of work of its neural structures. In experimental researches it is revealed that interconnected neuronal modules such as cortex, reticular modules of thalamus, specific thalamus play the important role in processes of information processing.

Dynamic modes of the sensor signal consciousness in neuron­like models: ways to the «neuromorphic» intellect and problems

Universal models of neuron­like type, from which the systems of transformation and identification of information signals are constructed in accordance with pre­determined goals are considered. The models of different levels in a model system are aimed at performing functional operations characteristic of live systems. The presented set of base models and the most obvious dynamic modes of their operation can adequately describe the features of conscious perception and response of live systems to various sensor signals.

Problems of modeling and analysis of infrared thermo maps human brain

This paper presents the approaches and methods for modeling and analysis of the open human cerebral cortex IR­thermo maps. The main goal of the development is to solve fundamental problems: the selection of reliable informative features, which allow detecting abnormalities of the brain, to classify its types, and to delineate its boundaries. The created analytical tools are also directed to the studying fundamental problems related to the mechanisms of autoregulation and compensation in the brain.

Reconstruction of an evolution operator as a technique of analysis of epileptiform electric brain activity

We propose a new method for analysis of electroencephalograms. It is based on construction of a parameterized stochastic model of the observed process (evolution operator). A certain functional form of the evolution operator is proposed. This form describes deterministic properties of the investigated process, as well as stochastic ones. The parameters of the evolution operator are reconstructed from the experimental data by using the Bayesian approach. New («fast») dynamical variables, which allow for the peculiar features of electroencephalogram, are found.

Analysis of epileptic activity of brain in case of absence epilepsy: applied aspects of nonlinear dynamics

The paper summarizes the main results of analysis of electroencephalograms in rats with genetic predisposition to absence epilepsy (WAG/Rij rat strain). Properties of epileptic activity are described in time and in frequency domains; dynamics of epileptic activity is investigated, as well as changes in electroencephalogram structure prior to epileptic discharges. Physiologic interpretation of the investigated phenomena helps in better understanding of the nature of the investigated phenomena.