Figure 4.

A, Within-session schematic for Experiment 1c, in which illumination was given in a manner contingent upon lever pressing in rats expressing eYFP, but not eArchT3.0 in IL pyramidal cells (i.e., a no-opsin, illumination-alone control, shown as an “X” during laser on epochs). B, Illumination had no effect on within-session lever pressing during shortened extinction sessions (left) or the retention of extinction learning (right). C, Illumination in rats expressing eYFP had no effect on the subsequent reinstatement of cocaine seeking. *p < 0.01 relative to extinction baseline.