Fig. 9: Modulation of stimulus contrast without spatial content.

a Sketch of the stimulus contrast modulation paradigm. Pixels were repeatedly illuminated with large-field illumination at 5 Hz (560 nm, 10 ms) for 3 s, and the irradiance level was changed every five pulses (0.9, 2.34 and 0.35 mW mm⁻²). The first change was a step increase while the second change was a step decrease. b Quantification of the ML firing rate (mean ± s.e.m.) under modulation of the stimulus contrast without spatial content (n = 12 RGCs). The cyan dashed lines are the average desensitised ML firing rates and the red dashed lines are the recovery thresholds. The grey dashed line is the average resting firing rate with its s.d. represented by the grey area.