Fig. 4.

Sustained On-cells responded to the light onset with sustained inward currents that lasted for at least 500 ms and included cells with morphologies consistent with brisk-sustained On and G4 cells. Peak inward currents (pA) at light onset were measured to identify transient components of the light responses, whereas area under the curve (AUC; average nA·1 s) was calculated to measure sustained components of the light responses. The average changes in peak currents and AUC of sustained On-cells with light responses that were significantly affected by pharmacological blockade are shown by cell type. ATR, atropine; HEX, hexamethonium bromide; MLA, methyllycaconitine.