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The basal forebrain contains several interdigitating anatomical structures, including the diagonal band of Broca, the basal nucleus of Meynert, the ventral striatum, and also cell groups underneath the globus pallidus that bridge the centromedial amygdala to the bed nucleus of the stria terminalis. Among the cell populations, the magnocellular, cholinergic corticopetal projection neurons have received particular attention due to their loss in Alzheimer's disease. In MRI images, the precise delineation of these structures is difficult due to limited spatial resolution and contrast. Here, using microscopic delineations in ten human postmortem brains, we present stereotaxic probabilistic maps of the basal forebrain areas containing the magnocellular cell groups. Cytoarchitectonic mapping was performed in silver stained histological serial sections. The positions and the extent of the magnocellular cell groups within the septum (Ch1-2), the horizontal limb of the diagonal band (Ch3), and in the sublenticular part of the basal forebrain (Ch4) were traced in high-resolution digitized histological sections, 3D reconstructed, and warped to the reference space of the MNI single subject brain. The superposition of the cytoarchitectonic maps in the MNI brain shows the intersubject variability of the various Ch compartments and their stereotaxic position relative to other brain structures. Both the right and left Ch4 regions showed significantly smaller volumes when age was considered as a covariate. Probabilistic maps of compartments of the basal forebrain magnocellular system are now available as an open source reference for correlation with fMRI, PET, and structural MRI data of the living human brain.

The human posterior insula was shown to respond to a wide variety of stimulation paradigms (e.g. pain, somatosensory, or auditory processing) in functional imaging experiments. Although various anatomical maps of this region have been published over the last century, these schemes show variable results. Moreover, none can directly be integrated with functional imaging data. Hence, our current knowledge about the structure-function relationships in this region remains limited. We therefore remapped the posterior part of the human insular cortex in 10 postmortem brains using an observer-independent approach. This analysis revealed the existence of 3 cytoarchitectonically distinct areas in the posterior insula. The examined brains were then 3D reconstructed and spatially normalized to the Montreal Neurological Institute single-subject template. Probabilistic maps for each area were calculated by superimposing the individual delineations, and a cytoarchitectonic summary map was computed to chart the regional architectonic organization. These maps can be used to identify the anatomical correlates of functional activations observed in neuroimaging studies and to understand the microstructural correlates of the functional segregation of the human posterior insula.

Software Testing is an established activity in the software development process to ensure and improve the quality of a software. Consequently, there exists a wide range of literature, popular information, and even multiple ISO standards covering this topic. However, we found that testing very large database management systems (DBMS) requires special adaptations of the generally available guidance for software testing and requires to solve specific challenges that may not be relevant for other areas or smaller software projects. We therefore discuss the testing of SAP HANA, a very large software project with millions of lines of code, to share insights about our approach, best practices, and unsolved challenges that are open for further research.

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