eLife assessment
This study presents a useful examination of dense neuroanatomy in human postmortem medial entorhinal cortex, using a large number of small electron microscopy image volumes sampled from multiple cortical layers and individuals. The authors use solid experimental and annotation techniques, demonstrating the suitability of postmortem tissue reconstructions for analysis and presenting careful, detailed measurements of synapse properties and overall tissue composition. However, there is inadequate support connecting these findings to claims about general connectivity in medial entorhinal cortex, since factors affecting interpretability like noise, the spatial scales examined, and relationships between structural properties and connectivity are not characterized. With a more thorough contextualization, this work would be of interest for studies of cellular neuroanatomy or brain network organization.