Neuroscience, the journal of the International Brain Research Organization (IBRO), will soon release a special issue entitled “Hippocampal vulnerability: from molecules to diseases“. Together with Robin de Flores & Gaël Chételat, we contributed to this issue with a review on MRI studies of hippocampal subfield structural changes in ageing and Alzheimer’s disease.
In a first section, we described the methodological aspects of subfield structural imaging and the technical evolutions over the last 15 years. We then described the major findings in normal ageing and different stages of Alzheimer’s disease (dementia, Mild Cognitive impairment, preclinical). Lastly, we summarized the results of studies reporting correlation between specific subfield(s) and memory scores assessing different subcomponents of memory.
Overall, this 218-reference review highlights the finding that in vivo neuromaging can capture the early differential vulnerability of hippocampal subfields in Alzheimer’s, and that subfield volumetry is more sensitive than classical whole hippocampal volumetry to AD-related changes. However, we also pointed a lot of inconsistent findings in aging and cognition-volume correlational studies. These contradictions are likely due to between-lab methodological differences, especially regarding subfiel definition on MRI data. This issue is currently under investigation by the hippocampal subfield group I am involved in.