Figure 7.

Optogenetic inhibition of VP GABA during cue presentation. A, Injection and fiber implant paradigm for targeting StGtACR2 to VP GABA neurons. B, Representative VP section with bilateral mCherry expression and fiber implant tracts. C, Fiber implant locations of stGtACR inhibition (n = 8) and mCherry control (n = 5) animals. D, DS task optogenetic test day trial design with continuous 473 nm laser on 50% of trials of each cue type. E, Port entry probability of stGtACR animals (n = 8) on the day before laser tests (laser duration, 0), 1 s laser test day, and up to 10 s laser test day, during DS trials with no laser (blue with black outline), DS trials with laser (light blue with cyan outline), NS trials with no laser (gray with black outline), and NS trials with laser (sea green with cyan outline). Data are represented as mean ± SEM. Dots represent individual rats. For pairwise follow-up comparisons, *p < 0.05. F, Average DS and NS port entry probability of control animals with and without laser (n = 5). G, Average DS and NS port entry latency of stGtACR animals with and without laser. H, Average DS and NS port entry latency of control animals with and without laser. I, Cumulative distribution plots of port entry latency in stGtACR animals for DS trials with no laser (medium blue), DS trials with laser (cyan), NS trials with no laser (black), and NS trials with laser (sea green) during sessions with 1 s inhibition (left) or up to 10 s inhibition (right). J, Cumulative distribution plots of control animals.