#Hippocampus anatomy histology free
The majority of its output is via the alveus into the fimbria which breaks free to the hippocampus to form the fornix. Information flows through the hippocampus proceeds from the dentate gyrus to CA3 to CA1 to the subiculum, with additional input information at each stage and outputs at each of the two final stages. NB: CA is an abbreviation of cornu Ammonis Pathways The hippocampus proper is made up of CA1, CA2 and CA3 fields (Figure 1). It has a head (posterior to the amygdala), a body, and a tail (which follows the upwardly curving lateral ventricle).Īlthough there is a lack of consensus relating to terms describing the hippocampus and the adjacent cortex, the term hippocampal formation generally applies to the dentate gyrus, fields CA1-CA3 (CA4 is frequently called the hilus and considered part of the dentate gyrus), and the subiculum ( parahippocampal gyrus). Our findings highlight new characteristics of internal hippocampal structure, and offer new avenues for its characterization with in-vivo neuroimaging.The hippocampus lies in the hippocampal sulcus immediately below the floor of the temporal horn of the lateral ventricle, and in cross section (coronal) has appearances that are reminiscent of a seahorse. Moreover, some features showed differences within subfields along the hippocampal longitudinal axis. Critically, we also show that morphological features alone are sufficient to derive most hippocampal subfield boundaries.
#Hippocampus anatomy histology manual
Unsupervised clustering of these features revealed subdivisions that closely resemble gold standard manual subfield segmentations. Third, we adapted neocortical parcellation techniques to map the hippocampus with respect to not only laminar but also morphological features. Second, we imposed a computational unfolding framework that respects the topological continuity of hippocampal subfields, which are traditionally defined by laminar composition. First, we leveraged a histological dataset with unprecedented 3D coverage, BigBrain. Here, we aimed to overcome this challenge using a unique combination of three methods. The internal structure of the human hippocampus is challenging to map using histology or neuroimaging due to its complex archicortical folding.