A local measure of symmetry and orientation for individual spikes of grid cells
Fig 4
Quantifying the global symmetry of firing patterns in the presence of shearing distortions or background noise.
a, b) Arrangement as in Fig 3a and 3b, but for generated spike maps with different degrees of shearing. Top: No shearing. Middle: Weak shearing. Bottom: Strong shearing. c) Arrangement as in Fig 3c but with increasing shearing strength on the horizontal axis. Shearing strengths for the examples shown in a are indicated with markers. d, e) Arrangement as in a, b, but for generated spike maps with different degrees of background noise. Top: No background noise. Middle: Weak background noise. Bottom: Strong background noise. f) Arrangement as in c but with increasing background noise (i.e., fraction of spikes drawn from a spatially homogeneous distribution) on the horizontal axis. Background noise levels for the examples shown in d are indicated with markers.