Estimated stability of grid cells for various biological oscillators.

Means and standard deviations of oscillator periods taken from the literature are averages over multiple cells (average of the mean period lengths and average of the standard deviations). Means and standard deviations taken from our original experimental data are given as both the average mean and average standard deviation over all cells as well as the single cells with the longest, median (where there were an even number of cells, the greater of the two “middle” cells is used), and shortest estimated duration of stability. Expected stability time is calculated using the equation as derived in the text for noise in pairs of oscillators (stability times should be doubled in models with no baseline oscillation). Experimental data is from this manuscript except where a reference is provided. For comparison, head direction cells are stable for around 120 seconds in the dark [38],[39], two orders of magnitude longer than the expected stability of the best of these biological oscillators. Abbreviations: standard deviation (Std.), entorhinal cortex layer II, III, or V (ECII, ECIII, ECV), postsubiculum (POS), medial septum theta bursting cell (MS burst), subthreshold membrane potential oscillations (smpo), persistent spiking (ps).