Temporal Dynamics of Distinct CA1 Cell Populations during Unconscious State Induced by Ketamine
(A) Spike rasters of chandelier interneurons (red) and simultaneously recorded pyramidal cells (blue) after ketamine injection, during running and slow-wave sleep are show (left panels). 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. The upper right panel shows this unit has negative correlation with pyramidal cell activities. (B) The properties of this example interneuron. The most upper left panel shows the average spike waveforms. The middle left panel illustrates the spike timing of this unit is strongly coupled with theta oscillations (p<0.001, Rayleigth's test). The lower left panel shows the firing rate significantly decreased during ripple epochs. (C) Autocorrelograms in different states: after ketamine injection, during running, and during sleep respectively. Autocorrelograms are shown in two time windows: 0–200 ms and 0–1.5 sec.