3.6 phosphene size
Statistics on the phosphene area revealed a significant main effect of intensity (F (1,24) = 15.518, p < 0.001, ηp2 = 0.393), indicating that the phosphene was perceived larger for the suprathreshold (90489.46 ± 22043.31) than the threshold (77891.75 ± 19484.09) stimulations. We also found a marginal effect of AM (F (1,24) = 4.113, p = 0.054, ηp2 = 0.146) that the phosphene sizes were larger for sinusoidal (91753.79 ± 24106.19) than for AM stimulation (76627.42 ± 19522.28). We did not find the main effect of polarity (F (1.5,34.8) = 0.329, p = 0.652, ηp2 = 0.014) nor any 2-way (polarity × AM: F (2,48) = 0.781, p = 0.464, ηp2 = 0.032; polarity × intensity:F (2,48) = 2.534, p = 0.090, ηp2 = 0.096; AM × intensity:F (1,24) = 0.252, p = 0.621, ηp2 = 0.010) or 3-way (F (1.5,37.1) = 1.282, p = 0.283, ηp2 = 0.051) interactions (Figure 2F).