Fig. 6: A tale of two memories.
From: Reactivating hippocampal-mediated memories during reconsolidation to disrupt fear
a Viral strategy and experimental design. To assess whether our reconsolidation-based manipulation was able to alter the original fear engram, we combined two viral strategies. All mice were injected with c-Fos-tTA-TRE-mCherry to tag dDG cells encoding the FC epoch. Mice were also injected with either undiluted AAV5-CaMKIIa-hChR2-H134R-eYFP or undiluted AAV5-CaMKIIa-eYFP to randomly label dDG neurons. Mice then underwent the same experimental protocol as before. b All mice froze post-shock (two-way RM ANOVA: F(1,11) = 85.26, P < 0.0001). c During recall, stimulation produced decreases in freezing (0–10) (P = 0.0392) in ChR2-mice compared to eYFP controls (two-way RM ANOVA: F(1,11) = 20.32, P = 0.0009, Time; F(1,11) = 6.468, P = 0.0273, Virus). d These differences persisted in EXT (Day 1: P = 0.0016; Day 2: P = 0.0127) (two-way RM ANOVA: F(1,11) = 15.05, P = 0.0026, Time; F(1,11) = 14.26, P = 0.0031, Virus). e No group differences were observed during IS. f During reinstatement, mice in the ChR2 group continued to show decreased of freezing (Unpaired t-test: t(11) = 5.768, P = 0.0001, two-tailed). g They also froze less at RE compared to IS (two-way RM ANOVA: F(1,11) = 22.40, P = 0.0006, Virus × Day). Data represented as means ± s.e.m. *P < 0.05, **P < 0.01, ***P < 0.005, ****P < 0.00. dDG: dorsal dentate gyrus, DOX doxycycline, EXT extinction, IS immediate shock, RE reinstatement. Source data are provided as a Source Data file.
