The BFCS map was processed as shown in Fig. 1. Most parts of the magnocellular nuclei of the BFCS are located in the substantia innominata, ventral to the anterior commisure. The ventral pallidum and parts of the nucleus accumbens are located in the rostral substantia innominata, The caudal parts of the substantia innominata are occupied by the extended amygdala. We used the Mesulam nomenclature for subregions of the BFCS [6 (link), 43 (link)]. The nuclei of the BFCS and their subregions were identified from the digital images of the histological sections and manually transferred into the corresponding slices of the MRI scan of the dehydrated brain. The MRI scan of the dehydrated brain was then transformed into the space of the postmortem in cranio scan using an initial 12-parameter affine transformation followed by a high-dimensional nonlinear registration [44 (link)] implemented in SPM8 software (Wellcome Trust Center for Neuroimaging). Next, the postmortem in cranio MRI was transferred into MNI standard space using the high-dimensional DARTEL (Diffeomorphic Anatomic Registration using Exponentiated Lie algebra) registration method [45 (link)]. The linear and non-linear transformations from alcohol through in cranio to MNI space were combined to spatially transform the basal forebrain mask into the MNI standard space. We used this map (i) to relate the voxel-wise group effects in local GM reduction to the anatomical position of the BFCS nuclei in MNI space and (ii) to automatically extract individual GM volumes for each BFCS subregion.