FIGURE 4.

Effect of patch size. Upper panels show the same example slice (in layers II/III) with different patch sizes for vignetting correction: (A) Patch size 32×32 pixels (denoted as p32); (B) 64×64 pixels (p64); (C) 128×128 pixels (p128); and (D) raw images without vignetting correction. In (E–G), the blue dots show the projections of all highly active cells (δX_l is larger than the mean value plus three times the standard deviation) in layers II/III on the x-y plane, calculated based on p32, p64, and p128, respectively, and the red diamonds represent the highly active cells calculated based on the raw images. (H) Shows the overlap rates (|H_i∩H_j|/|H_i|) of highly active cells between any pair of the aforementioned images, where H_i denotes the set of highly active cells from the reference image, H_j from the image used for comparison, and |⋅| denotes the cardinality of the set.