a, To unambiguously compute CS Scores for each nonmnemonic behavioral factor given the fMRI signal’s hemodynamic lag, each factor must be temporally autocorrelated during Squircle trials within and across fMRI volumes. To determine the temporal autocorrelation within fMRI volume (TR), we computed the percentage of timepoints during which nonmnemonic factors were the same between timepoint t and t + N, where N corresponds to 19 lags from 51–969 msec from t (that is, at the behavioral sampling rate—20 Hz), within a single TR during Squircle trials. Nonmnemonic factors include VR-locomotion (VR-walking or -stationary), location (most proximal boundary segment, either Square or Circle), boundary view (toward Square or Circle boundary segment), distal cue view (toward Square or Circle distal cue). To control for potential nonuniform sampling within each nonmnemonic factor, percentages were converted to z-scores by randomly shuffling each nonmnemonic factor across timepoints separately for each participant (k = 500). Each nonmnemonic factor was more similar across successive timepoints within TRs at all lags than expected by chance (color bars denote p-values from one-sample t-tests compared to 0 baseline; all t23 > 9.82, p < 10−8). Light gray lines denote individual participants (n = 24), black line denotes group mean. b, Same as in (a) but between successive TRs (lags 1–10 TRs) during Squircle trials. Red dotted lines denote the lag N at which a given nonmnemonic factor was no more likely to be the same at time t than t + N (t-test, p > 0.05, uncorrected for multiple comparisons), if at all. Participants tended to occupy the same behavioral state for multiple TRs. c, Percentage of time during Squircle trials that participants VR-turned (mean angular velocity >0 deg/sec) between successive TRs during VR-walking and -stationary epochs. Participants VR-turned more often during VR-stationary than -walking epochs (t23 = 17.28, p = 1.13 × 10−14). This result also implies that both boundary view and distal cue view were more similar across successive TRs during VR-walking than VR-stationary epochs. Error bars indicate ±1 SEM. Dots denote individual participants (n = 24). Throughout the figure, all t-tests two-tailed. ***p < 0.001.