Fig. 4: Decoding accuracy for square luminances by responses to edge or surface in V1.

a Temproal development of decoding accuracy for luminance (shadings represent ±s.e.m.) based on surface responses (red lines) or edge responses (blue lines) of neural populations (n = 100) in L4C or L2/3. Each population include 32 sites randomly sampled from all sites in L4C or L2/3. The accuracy during the sustained response time (80–250 ms, between two dashed vertical lines) were averaged for the following comparison (b–e). b Performance of luminance decoders using surface responses (red bars) and edge responses (blue bars) in L4C and L2/3. The number of sites for each decoder was kept constant at 32. ***p < 0.001, two-sided paired t-test (between surface and edge) and independent t-test (between L4C and L2/3). Bars represent mean accuracy across populations (±s.e.m.), with individual data (n = 100) superimposed. The definitions for bars in d and e are the same as that for b. c Accuracy differences for decoding luminances between surface response and edge response in L4C and L2/3 are consistent regardless of the number of sites included in the decoder. Error bars represent s.e.m. across 100 populations. d Decoding performance for luminance recognition of white (white bars) or black (black bars) by surface responses (left) or edge responses (right) at input or output layers. ***p < 0.001, two-sided paired t-test, n = 100 populations. e Decoding performance of surface data with high sustainability (filled bars) or low sustainability (open bars). ***p < 0.001, two-sided independent t-test, n = 100 populations. f The correlation between sustainability of surface response (x-axis) and decoding weight (y-axis). The relationship between decoding weights and sustain index of response were shown in the subplots with light dots (left) for white conditions and in the subplots with dark dots (right) for black conditions. The upper panels show data from the input layer, and the lower panels show data from the output layer. Pearson correlation coefficient (r) were calculated from the sites with decoding weight not equal to 0 (n = 35 for L4C; n = 41 for L2/3). Source data are provided as a Source Data file.