Imagine the hippocampal subfields as different neighborhoods in your brain. These neighborhoods play a crucial role in forming and recalling memories. But studying them is like trying to find hidden treasures in a crowded city. The small size of these subfields and the lack of a standardized method for studying them make it challenging to compare findings across different studies. That’s why scientists introduced a new tool called HSF (hippocampal segmentation factory). It’s like having a super-powered GPS that can accurately navigate through these brain neighborhoods! They used HSF to study the subfields in over 3,750 individuals and found fascinating results. First, HSF showed better accuracy compared to other tools, matching manual segmentations more closely. Second, they discovered that certain subfields mature and age at different rates, with the dentate gyrus being the most affected by age. Additionally, they found that men’s and women’s subfields grow and decline at different speeds. These findings resolve conflicting results from previous studies. To dive deeper into the world of hippocampal subfields and explore the research behind HSF, check out the full article!

The hippocampal subfields, pivotal to episodic memory, are distinct both in terms of cyto- and myeloarchitectony. Studying the structure of hippocampal subfields in vivo is crucial to understand volumetric trajectories across the lifespan, from the emergence of episodic memory during early childhood to memory impairments found in older adults. However, segmenting hippocampal subfields on conventional MRI sequences is challenging because of their small size. Furthermore, there is to date no unified segmentation protocol for the hippocampal subfields, which limits comparisons between studies. Therefore, we introduced a novel segmentation tool called HSF short for hippocampal segmentation factory, which leverages an end-to-end deep learning pipeline. First, we validated HSF against currently used tools (ASHS, HIPS, and HippUnfold). Then, we used HSF on 3,750 subjects from the HCP development, young adults, and aging datasets to study the effect of age and sex on hippocampal subfields volumes. Firstly, we showed HSF to be closer to manual segmentation than other currently used tools (p < 0.001), regarding the Dice Coefficient, Hausdorff Distance, and Volumetric Similarity. Then, we showed differential maturation and aging across subfields, with the dentate gyrus being the most affected by age. We also found faster growth and decay in men than in women for most hippocampal subfields. Thus, while we introduced a new, fast and robust end-to-end segmentation tool, our neuroanatomical results concerning the lifespan trajectories of the hippocampal subfields reconcile previous conflicting results.

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