Figure 13.

Effects of interrupting or brightening a steady light on membrane potential in turtle long-wavelength cones. The cones were stimulated with a steady light of intensity equivalent to 3.74 × 10⁴ photons μm⁻²s⁻¹ at the optimum wavelength of 644 nm. (a) The steady light was turned off for 40 ms or the intensity was doubled for 40 ms. The resulting changes in membrane potential were averaged in a few frames and plotted (continuous lines, open symbols), (b) decrement, (c) increment. (Adapted from Figure 14, Baylor, Hodgkin, & Lamb, 1974a, p. 714).