Abstrakt:
Complex neurodynamical systems are quite
difficult to analyze and understand. New type of plots are
introduced to help in visualization of high-dimensional
trajectories and show global picture of the phase space,
including relations between basins of attractors. Color
recurrence plots (RPs) display distances from each point on
the trajectory to all other points in a two-dimensional
matrix. Fuzzy Symbolic Dynamics (FSD) plots enhance this
information mapping the whole trajectory to two or three
dimensions. Each coordinate is defined by the value of a
fuzzy localized membership function, optimized to visualize
interesting features of the dynamics, showing to
which degree a point on the trajectory belongs to some
neighborhood. The variance of the trajectory within the
attraction basin plotted against the variance of the synaptic
noise provides information about sizes and shapes of these
basins. Plots that use color to show the distance between
each trajectory point and a larger number of selected reference
points (for example centers of attractor basins) are
also introduced. Activity of 140 neurons in the semantic
layer of dyslexia model implemented in the Emergent
neural simulator is analyzed in details showing different
aspects of neurodynamics that may be understood in this
way. Influence of connectivity and various neural properties
on network dynamics is illustrated using visualization
techniques. A number of interesting conclusions about
cognitive neurodynamics of lexical concept activations are
drawn. Changing neural accommodation parameters has
very strong influence on the dwell time of the trajectories.
This may be linked to attention deficits disorders observed
in autism in case of strong enslavement, and to ADHD-like
behavior in case of weak enslavement.
