Fig. 3
From: Orchestrated ensemble activities constitute a hippocampal memory engram
Engram cells show characteristic activity during contextual learning. a Normalized calcium transients for all engram cells (top) and non-engram cells (bottom) during contextual exposure (displayed over time). b Typical overlap M (t, t’) between correlation matrices at two time points (see Methods) for non-engram (left), engram (middle) and shuffled engram (right) cells within the first 60 s of calcium imaging. c Temporal sum of overlaps Mtot(t) (see Methods) from a representative animal. d The average sum of overlaps in engram cells and shuffled engram cells, that is, the summation of Mtot(t) over time during the first 60 s of calcium imaging relative to the sum from non-engram cells. Statistical comparisons were conducted using the Wilcoxon’s signed-rank test, two-tailed. n = 10; (engram vs. non-engram) t(9) = 2.01, p = 0.037 (engram vs. shuffled engram) t(9) = 6.81, p = 0.000038; *p < 0.05, **p < 0.01. Data represent the mean ± s.e.m. across all animals
