Ex vivo Mesoscale human temporal lobe dataset

The human hippocampus is essential to cognition and emotional processing. Its function is defined by its connectivity. Although some pathways have been well-established, our knowledge about anterior-posterior connectivity and the distribution of fibers from major fiber bundles remain limited. Mesoscale (250 mm isotropic acquisition, upsampled to 125 mm) resolution MR images of the human temporal lobe afforded a detailed visualization of fiber tracts, including those that related anterior-posterior substructures defined as subregions (head, body, tail) and subfields (cornu ammonis 1-3, dentate gyrus) of the hippocampus. Fifty pathways were dissected between the head and body, highlighting an intricate mesh of connectivity between these two subregions. Along the body subregion, 12 lamellae were identified based on morphology and the presence of interlamellar fibers that appear to connect neighboring lamellae at the edge of the external limb of the granule cell layer (GCL). Translamellar f..., Magnetic Resonance Imaging
Samples were placed in an 9.4.7T/30 cm Bruker AV3 HD microimaging scanner equipped with a B-GA12S HP gradient set capable of 660 mT/m maximum gradient strength and a 72 mm quadrature birdcage resonator running Paravision 6.0.1 (Bruker Biospin, Billerica, MA) with a 72 mm inner diameter quadrature birdcage RF coil. Multi-shell diffusion MR images were acquired with a 3D diffusion-weighted multi-shot spin-echo EPI sequence with the following parameters: TR = 500 ms, TE = 26 ms, diffusion duration δ = 5 ms, diffusion spacing Δ = 13 ms, EPI segments = 30. A 1.2 partial Fourier acceleration in PE1 was used with a zero-filling acceleration factor 1.2 in the read and PE2 dimensions for an isotropic resolution of 250 μm. A total of 94 images were collected with diffusion-weighted shells consisting of b = 1000, 2000, 4000, 6000 s/mm2 with 12, 18, 24, 36 directions, respectively (~68 hours total scanning time). Each shell was acquired separately and included 2 B0 images..., , # Ex Vivo Mesoscale Human Temporal Lobe Dataset

[https://doi.org/10.5061/dryad.jh9w0vtnq](https://doi.org/10.5061/dryad.jh9w0vtnq)

## Description of the data and file structure

Mesoscale diffusion MRI data was acquired at a 250 um isotropic resolution. Processing using DSI studio upsampled this 2x to 125 um resolution dataset to provide a more detailed anatomical context. The entire human temporal lobe is available for 16 subjects at various ages, as described in the article accompanying this data set.

### Files and variables

A total of 16 individual .fib files contained processed diffusion MR images for tractography and diffusion measurements are contained within the *MRI_GQI__Files.zip* file. Details about each subject can be found in Table 1 of the accompanying publication. Each file belongs to 1 subject. Matching ROIs are contained in 5 separate zip files: *ROIs_fimbria.zip, ROIs_hippocampus.zip, ROIs_regional_subfields.zip (head, body, tail), ROIs_HC_subfields.zip (CA1, CA2, C...,