[Frequency modulation of theta volleys of septal neurons during rhythmic oligosynaptic stimulation in the rabbit].
Activity of the neurones with stable theta-bursts was recorded extracellularly in intact and hippocampectomized septum of unanaesthetized chronic rabbits during low-frequency (3-17 Hz) stimulation of horizontal limb of the diagonal band or the lateral septal nucleus. Gradual entrainment and phase-locking of the spontaneous theta-cycles occurred. Two types of entrainment were observed: "entrainment by pause", where interburst interval was reset by the stimuli; and "entrainment by burst", where bursts were time-locked to the stimuli. Such reorganization of the spontaneous bursts occurred in a narrow frequency range of stimulation (from 4 Hz up to 9-12 Hz), with the best resonance following in the range of "basic" theta frequencies of the awake rabbit (5-6 Hz). With stimulation beyond the theta-range three phenomena occurred: shift of the burst frequencies to higher or lower harmonics of stimulation frequencies; complex interactions of basic background frequency with the rhythm of stimulation ("beating"); escape from the influence of the stimuli with return to background theta-burst frequency.
D000818:Animals; D001931:Brain Mapping; D005071:Evoked Potentials; D008032:Limbic System / Q000502:physiology*; D008474:Medial Forebrain Bundle / Q000502:physiology; D008636:Mesencephalon / Q000502:physiology; D009434:Neural Pathways / Q000502:physiology; D011817:Rabbits; D012154:Reticular Formation / Q000502:physiology; D012686:Septal Nuclei / Q000502:physiology*; D009435:Synaptic Transmission; D013826:Theta Rhythm
Chastotnaia moduliatsiia teta-zalpov septal'nykh neĭronov pri ritmicheskoĭ oligosinapticheskoĭ stimuliatsii u krolikov.