Figure 5.

Emergence of a spurious correlation with speed during spontaneous behavior

(A) Hypothetical scenario of the confusion emerging from the concatenation of multiple speed peaks. From top to bottom in arbitrary units: speed (gray), acceleration (black), theta frequency responding only to acceleration (red).

(B) Three versions of a simple model for the evolution of theta frequency (color) during a Gaussian speed peak (gray) and corresponding acceleration (black). From top to bottom, the relationship between theta frequency and acceleration is modeled in arbitrary units as linear (M1, yellow), rectified linear (M2, cyan), or rectified linear with a slow decay (M3, red, used in A).

(C) Average post-peak decay of acceleration (black) or theta frequency (red) for the pool of all open field data (as in Figure S1D, bottom). Variables are normalized so that 1 corresponds to the value at the peak, whereas 0 corresponds to 0 cm s⁻² or baseline theta frequency. The slow decay dynamics of theta frequency is described as decaying exponentially with a constant of 0.2 s (dashed line).

(D) Pearson correlation between modeled theta frequency and speed or acceleration for M1 to M3 (color coded).

(E) For the pool of all open field data, windows of 1 s to each side of a speed peak (top) or an acceleration peak (bottom) are defined. Averages over all such windows of recorded speed (gray), acceleration (black) and MEC theta frequency (green) are shown. y axis: percentage of variation between minimum and maximum positive values. Note resemblance with M3.