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).