Figure 1.

(A) LHb inactivation disrupts temporal stability of IA memory. Animals were trained in the IA 30 min after injection of muscimol or vehicle (saline) in the LHb. Muscimol injection did not affect memory retention in the 24 h tested group but induced a clear memory impairment in the 7 days tested group. (B) Top: Injection of muscimol immediately after IA training did not induce amnesia. Centre: Injection of muscimol 6 h after IA training did not induce amnesia. Bottom: Injection of muscimol 12 h after IA training did not induce amnesia. (C) Temporal stability of weak IA LTM is not impaired by LHb inactivation. Rats were trained in the IA using a weak training 30 min after injection of muscimol or vehicle in the LHb. Muscimol injection facilitated memory tested 24 h after training but did not affect retention 7 days after training. (D) Inhibition of protein synthesis in the LHb during training does not disturb temporal stability of IA LTM. Injection of anisomycin or emetine in the LHb 15 min before IA training did not impair memory retention. ^*p < 0.05; ^***p < 0.001.