Fig. 4.

Functional evidence that avBST→PVH pathway inactivation enhances memory consolidation. (A and B) Mean ± SEM of plasma ACTH (A) and CORT (B) in no-laser control and laser Halo groups before (0 min) and at various intervals following IA training. Both hormones are significantly increased in the Halo group at various intervals following illumination. (A and B, Inset) Integrated ACTH and CORT responses (AUC) were also significantly increased in the Halo versus control groups. (C) Posttraining inhibition of avBST neurons enhanced retention when measured 48 h later. (D) Raster plots (Upper) of action potentials over a 15-min recording session in the absence (gray) and presence (green) of 561-nm illumination. The summary histogram (Lower) reveals an increase in frequency relative to baseline activity above. (E–G) avBST→PVH pathway stimulation with ChR2 failed to alter posttraining levels of plasma ACTH (E) and CORT (F), or retention latencies (G) when assessed 48 h later. *P < 0.05.