The correlations of EGR1 expression per mm 2 versus the time spent in the cocaine compartment during the cocaine CPP reacquisition/re-expression test are shown for animals that had undergone cocaine conditioning, followed by extinction with saline (red triangles, filled) and for animals that were counterconditioned with social interaction after an initial cocaine conditioning (green circles, filled) before being subjected to a final cocaine challenge and tested for the reacquisition/re-expression of cocaine 24 h later.
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