Temporal Dynamics of Distinct CA1 Cell Populations during Unconscious State Induced by Ketamine
(A) Spike rasters of silmultanously recorded pyramidal cells (blue) and type-6 interneurons (red unit is plotted for B and C) during ketamine anesthetic state, running, and slow-wave sleep are shown (left subpanels). Other two simultaneously recorded type-6 interneurons are in orange. The cross-correlation functions of the interneuron and pyramidal cell joint-activities are plotted on the right. The black line is the cross-correlation during the awake rest state. (B) The basic properties. The most upper left panel shows the average spike waveforms. Firing probability histograms during theta and ripples are shown in middle left and lower left panels respectively. (C) Autocorrelograms in different states: after ketamine injection, during running, and during sleep respectively. Autocorrelograms are shown in two time scales: 0–50 ms and 0–1.5 sec. Note the slow oscillatory dynamics are shown in both the cross-correlation plot and the larger time scale autocorrelogram after ketamine injection. This unit exhibits a burst firing pattern during sleep shown in the peak within 10 ms in the autocorrelogram.