[Neuroautonomic organization of cardiac rhythm and of nonrhythmic oscillations in the frequency of cardiac contractions and respiration].

In 25 chronic adult rabbits, the functional organization of neurally mediated short-term rhythms and patterns of the heart rate (HR) were investigated. The respiration-unrelated arrhythmia seems to be vagally mediated only, being abolished with atropine. The respiration-related arrhythmia exists not only within the range of respiratory frequency but also in lower frequencies as discovered by spectral and coherence analysis. During motor activity, there is a systematic correlation among increasing premotor, motor and amygdaloid multispike activities, increasing HR and depressed HR-rhythms with limbic initiation of motor and concomitant autonomic patterns, "Immobile confrontations" alone produces vagally induced HR-decrease and increased amplitudes of vagal HR-rhythms with a concomitant cortical multispike depression, a mirror image of the autonomic patterns after nociceptive stimulation.