Fig. 8.
Parameters of the intensity–response curve. A scatter plot of the two parameters of the Hill function, V p (abscissa), and the slope, h (ordinate). Black dots represent estimates for 50 individual cells where the function fit converged well. Solid circles with crosses are group averages (mean ± SD; number of cells in classes: UV 4, V 3, nB 5, bBb 3, bBs 5, bG 18, nG 8, R 4). The thick solid cross is the grand average calculated from individual cells (mean ± SD): V p = 41.1 ± 6.8 mV and h = 0.73 ± 0.09. The regression line, based on individual cells (h = 0.99 − 0.0064 V p; r 2 = 0.24), shows a weak correlation between a lower maximal response and a steeper slope. The edge histograms show the distributions of the two parameters