This is a met-analysis. The majority of available hippocampal data was processed using FreeSurfer, an outdated and generally inaccurate segmentation method for

This is a met-analysis. The majority of available hippocampal data was processed using FreeSurfer, an outdated and generally inaccurate segmentation method for the hippocampus (Lee et al., 2015; although FreeSurfer is good for cortical thickness and surface estimation). However, given large potential changes due to age-related atrophy, that particular method might be sensitive enough in aggregate. I've seen lots of older brains in the MRI, and it is not pretty. A lot of atrophy is probably due to cardiovascular-related disease and degeneration. Seeing enough of those brains finally got me off my chair and jogging. I feel great because of it too.