Nonlinear Dynamics in a Compound Central Pattern Generator
We studied the nonlinear dynamical behavior of several compound central pattern generators in the form of a half-center network oscillator coupled with an endogenous pacemaker, as exemplified by the respiratory motor generator in the mammalian neonate. Using pacemaker inputs with varying amplitudes, frequencies and phases, we demonstrated several pathologic oscillatory patterns including recurrent apnea (intermittent cessation of oscillation), quasi-periodic fluctuations and chaos. The apneic pattern can be attributed to decreased excitation (e.g., decreased overall chemoreceptor activity), unbalanced excitation (e.g., unbalanced tonic inputs to inspiratory and expiratory related neurons), or disparity between the intrinsic oscillatory frequency and pacemaker frequency. Results may have important implications in the pathogenesis of abnormal respiratory pattern associated with sudden infant death syndrome.
KeywordsRespiratory Rhythm Expiratory Neuron Oscillatory Input Spontaneous Frequency Chemoreceptor Activity
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