Minkova L, et al. – The aim of this work was to conduct a systematic review and meta–analysis to evaluate gray matter (GM) loss and its lateralization in healthy aging and in neurodegeneration, namely, mild cognitive impairment (MCI), Alzheimer's dementia (AD), Parkinson's disease (PD), and Huntington's disease (HD). The right hippocampus was more atrophic than its left counterpart, a pattern that reversed in AD in MCI. The stability of these findings was confirmed applying permutation tests. Nevertheless, due to the lenient threshold applied in the asymmetry analysis, further work is required to confirm the outcomes and to serve a better understanding of the functional role of GM asymmetries, for instance in the context of cognitive reserve and compensation.