Differential Consolidation and Pattern Reverberations within Episodic Cell Assemblies in the Mouse Hippocampus
(A) MDA analysis on mouse #1 shows that CA1 ensemble representation of high drop experiences is located farther away from the resting state in the projection subspace than the clusters corresponding to low or medium drop episodic startles. (B) Quantification of the average distances away from the rest origin for all episodic events plotted in panel A illustrates that classification of higher drops are indeed located further away from the resting state in the encoding subspace. (C) A data set from another mouse hippocampus (mouse #2) is characterized by a large separation between high drop (third type of drop from a 30 cm height) and the basal activity cluster, when compared to the separation between low drop (first type of drop from a 5 cm height) or medium drop (second type of drop from an 11 cm height). (D) Inspection of the average distances away from the origin of the basal activity (gray), air-blow (light blue) and drop clusters (dark blue) confirm with the trends suggested by panel C. (E) Results from a third data set (mouse #3) indicate that while air-blow at low intensity evoked little ensemble response, air-blow at middle and high intensity evoked considerably larger responses. (F) Quantification of distances away from origin by various clusters is in agreement with panel E. Overall, these three examples illustrate the general tendency from all our data sets: the stronger the parametric stimulus, the better the separation from rest cluster in encoding subspace.