Extended Data Figure 3: Orientation clustering.
From: Grid cell symmetry is shaped by environmental geometry
a, The autocorrelogram of the distribution of grid orientations in squares (shown in Fig. 1b). b, The Fourier spectrogram of autocorrelogram in a, left, and a typical example of the Fourier spectrogram of the autocorrelogram of shuffled orientations, right. Note the absence of a low-frequency peak in the latter. c, The distribution of maximum normalized Fourier power of 10,000 data surrogates (as shown in b, right). Red line indicates 95 percentile of the shuffled data. Blue line indicates the maximum normalized Fourier power of our data.
