For almost two decades, O'Brien and colleagues have investigated virtually every facet of dementia with Lewy bodies (DLB), phenomenology, treatment, and neurobiology, ranging from genetics to post-mortem and in vivo imaging studies. The latest study from this group, reported here, describes differences in regional grey matter volumes using magnetic resonance (MR) imaging and an automated segmentation analysis method in a well-characterized sample of patients with Alzheimer disease (AD), DLB, and a healthy control group (Watson et al., 2015). The study incorporated detailed psychometric assessments of cognitive and motor functions for correlation with the grey matter volumes, and age, gender and dementia severity were included as covariates in the statistical analysis. The key observations are relatively greater hippocampal volumes and lower subcortical volumes in DLB compared to AD, but it is to be noted that most of these differences in subcortical volume were demonstrated indirectly through comparisons of the disease groups with age-matched healthy control subjects. Thus, replication in studies that make direct comparisons between DLB and AD subjects, perhaps in a larger sample size, is necessary. Still, these results highlight the potential for MR imaging to provide indicators of the extent of the neurodegenerative process in DLB. Furthermore, the results underscore the importance of correcting molecular imaging data for the effects of cerebral atrophy (partial volume correction) that may further enhance the ability of these methods to reveal pathophysiological processes.