Power spectral analyses of inspiratory activities in neonatal pigs.

In anesthetized neonatal pigs, spectral analyses were done for inspiratory nerve and neuronal activities. Peaks in power spectra of phrenic roots were observed at high frequencies and at medium frequencies. In contrast, peaks in recurrent laryngeal and hypoglossal nerve spectra were found only at medium frequencies. Significant coherence estimates were obtained only at medium frequencies, indicating that different motoneuron pools share inputs from a common neural oscillator.