Histology for intracranial cannulations. a, Schematic representation of the intra-HPC infusion needle tip placement from a typical group of animals (STM assessment following SPV106+ low-dose ICI-182-780). Cannulas were consistently located at 3.60 mm posterior to the bregma (Paxinos and Watson, 1998) for all dHPC-cannulated rats. b, Photomicrograph (1.25× magnification) of thionin-stained section illustrating the cannula tract terminating in the dHPC. c, Schematic representation of the intra-PRh infusion needle tip placements from a typical group of animals (SPV106 administration; enhanced LTM but not STM). Cannulas were consistently located between 5.80 and 6.30 mm posterior to the bregma (Paxinos and Watson, 1998) for all PRh-cannulated rats. d, Photomicrograph (1.25× magnification) of thionin-stained section illustrating the tract of a cannula terminating in the PRh.