(A) Comparison of grid field size when sampled in different speed ranges. Field size (as a percentage of the area of the environment) were significantly different across the three speed ranges (n = 61, F(2, 120)=7.06, p<0.01) and between VR and R environments (n = 61, F(1, 60)=21.28, p<0.001) but there was no interaction between effects of speed and environment on size (n = 61, F(2, 120)=0.52, p=0.60). (B) Comparison of place cell field size when sampled in different speed ranges. Field sizes were different across speed ranges (n = 154, F(2, 306)=11.13, p<0.001), the effect of environment approached significance (F(1,153)=3.50, p=0.06) and there was no interaction between effects of environment and speed (F(2, 306)=1.98, p=0.14).