# Imaging platform and computational HARDI atlas of the human hippocampus

> **NIH NIH R01** · JOHNS HOPKINS UNIVERSITY · 2021 · $360,052

## Abstract

Summary
The hippocampal formation is a structure of acute interest in neuroimaging, due to its crucial role in a wide
spectrum of neurological disorders, including epilepsy, schizophrenia, and Alzheimer’s disease (AD). Three-
dimensional mapping of the complex intra-hippocampal organization and subfield connectivity is of paramount
importance, since different subregions of the hippocampus are known to exhibit selective and differential
vulnerability to different neurological diseases, such as epilepsy and AD. Despite its central role in major
neurological disorders, the internal laminar microstructure and subfield connectivity of the human hippocampus
remain difficult to delineate with three-dimensional imaging techniques.
The goal of this R01 proposal is to develop the first three-dimensional diffusion MRI computational atlas of the
intact whole human hippocampus. The proposed atlas will build on key technical developments enabling
combined high spatio-angular resolution diffusion MRI (dMRI) of the intact fixed hippocampus at 11.7T. The
resulting atlas based on high angular resolution diffusion imaging (HARDI) data from multiple hippocampus
specimens will provide delineation of human intra-hippocampal organization and circuitry in unprecedented
microstructural detail. Further, current understanding of hippocampal circuitry and its disruption in disease is
largely based on two-dimensional histological sections. The imaging platform and dMRI atlas established here
will allow for the first time, investigation and three-dimensional mapping of region-specific changes in intra-
hippocampal structure in normal aging and AD brains, providing details of hippocampal pathology in greater
detail than previously possible. We will achieve these goals in four specific aims: (1) to develop accelerated
three-dimensional diffusion MRI techniques for efficient sampling of the combined (k,q)-space, (2) to acquire
combined high spatio-angular resolution 3D dMRI data of whole hippocampal specimens at 11.7T, (3) to
construct a computational averaged HARDI atlas of the whole hippocampus using a diffeomorphic non-linear
registration framework based on rotation-invariant HARDI features and Riemannian averaging, and (4) to
investigate regional changes in intra-hippocampal structure in normal aging and AD. This project brings
together innovative imaging techniques and computational analysis methods, that will allow development of the
high-field dMRI atlas with microstructural detail. Upon completion, these goals will establish the first HARDI
atlas of the human hippocampus, which will be an invaluable resource for neuroimaging studies, and provide
significant insights to advance our understanding of hippocampal pathology in AD and aging.

## Key facts

- **NIH application ID:** 10135804
- **Project number:** 5R01AG057991-04
- **Recipient organization:** JOHNS HOPKINS UNIVERSITY
- **Principal Investigator:** Manisha Aggarwal
- **Activity code:** R01 (R01, R21, SBIR, etc.)
- **Funding institute:** NIH
- **Fiscal year:** 2021
- **Award amount:** $360,052
- **Award type:** 5
- **Project period:** 2018-07-01 → 2023-03-31

## Primary source

NIH RePORTER: https://reporter.nih.gov/project-details/10135804

## Citation

> US National Institutes of Health, RePORTER application 10135804, Imaging platform and computational HARDI atlas of the human hippocampus (5R01AG057991-04). Retrieved via AI Analytics 2026-05-22 from https://api.ai-analytics.org/grant/nih/10135804. Licensed CC0.

---

*[NIH grants dataset](/datasets/nih-grants) · CC0 1.0*