An excitable medium is a nonlinear dissipative dynamical system able to sustain undamped wave propagation. Examples of excitable media include cardiac tissue and neural media. This thesis investigates a class of novel dynamical phenomena in excitable media, known collectively as oscillatory waves. The examples of oscillatory waves considered here are Tango waves, breathers and pulse generators....

Neuronal response synchronization with millisecond precision has been proposed to serve feature binding in vision and should therefore, like visual experience, depend on central states. Here we test this hypothesis by examining the occurrence and strength of response synchronization in areas 17 and 18 of anesthetized cats as a function of central states. These were assessed from the frequency c...

BACKGROUND Oscillatory breathing patterns characterized by rises and falls in ventilation with apnea (Cheyne-Stokes respiration [CSR]) or without apnea (periodic breathing [PB]) commonly occur during the daytime in chronic heart failure (CHF). We have prospectively characterized patients with cyclical breathing in terms of clinical characteristics, indices of autonomic control, prognosis, and t...

A new algorithm for the detection of oscillatory events in the EEG is presented. By estimating autoregressive (AR) models on short segments the EEG is described as a superposition of harmonic oscillators with damping and frequencies varying in time. Oscillatory events are detected, whenever the damping of one or more frequencies falls below a predefined threshold. The algorithm works well for t...

In this chapter we will present support for the hypothesis that synchronous neuronal activity of cell assemblies within the auditory cortex could be the underlying neural code of tinnitus. Such synchronous activity is reflected in the ongoing oscillatory activation pattern that can be recorded non-invasively using MEG and EEG techniques. We conclude that such an oscillatory model of tinnitus ca...

The dynamics and stability of spike-type patterns to a sub-diffusive Gierer-Meinhardt reaction – diffusion system is studied in a one dimensional spatial domain. A differential algebraic system (DAE) is derived to characterise the dynamics of an n-spike quasi-equilibrium pattern in the presence of subdiffusion. With sub-diffusive effects it is shown that quasi-equilibrium spike patterns exist f...

The oscillatory movements of atmospheric air masses has been claimed to be the origin muon flux variation measured at ground level. Using a cosmic ray toolkit (CORSIKA), we simulate cascade scenarios in time scale year and show dependence pattern with proposed model atmosphere.