Weak and strong IA memory retrieval induce differential hippocampal ERK1/2 activity.
Post-retrieval dHIP ERK2 inhibition impairs memory reconsolidation tested at 24 h.
dHIP ERK inhibition 3 h after retrieval impairs persistent-LTM at 7 days.
dHIP ERK inhibition effect on persistent-LTM is retrieval-dependent/retrieval-induced.