Photomicrographs were taken with an Olympus microscope BX3 and Olympus DP73 digital camera. Regions of interest were defined in accordance with the mouse brain atlas based on specific landmarks that comprise cellular groups. The anterior–posterior (AP) level from the bregma of the analyzed regions was as follows: BLA (AP: − 0.6 mm to − 0.26 mm), vHIP (AP: -2.8 mm to -3.8 mm) and mPFC (AP: 2.34 mm–1.34 mm). c-Fos immunoreactive profiles were captured from a fixed area under 200 × magnification in at least 3 sections per region per mouse and quantified using ImageJ software (NIH, Bethseda, MD). Given that c-Fos expression levels did not differ between the left and right sides regions in response to any of the experimental procedures, counts were averaged to yield the mean number of c-fos-positive profiles per region per animal.