1 nature portfolio  |  reporting summary April 2023 
Corresponding author(s):
Laura Pritschet, Elizabeth R. Chrastil, & Emily 
G. Jacobs
Last updated by author(s): 06/30/2024
Reporting Summary
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Statistics
For all statistical analyses, confirm that the following items are present in the figure legend, table legend, main text, or Methods section.
n/a Confirmed
The exact sample size (n) for each experimental group/condition, given as a discrete number and unit of measurement
A statement on whether measurements were taken from distinct samples or whether the same sample was measured repeatedly
The statistical test(s) used AND whether they are one- or two-sided 
Only common tests should be described solely by name; describe more complex techniques in the Methods section.
A description of all covariates tested
A description of any assumptions or corrections, such as tests of normality and adjustment for multiple comparisons
A full description of the statistical parameters including central tendency (e.g. means) or other basic estimates (e.g. regression coefficient) 
AND variation (e.g. standard deviation) or associated estimates of uncertainty (e.g. confidence intervals)
For null hypothesis testing, the test statistic (e.g. F, t, r) with confidence intervals, effect sizes, degrees of freedom and P value noted 
Give P values as exact values whenever suitable.
For Bayesian analysis, information on the choice of priors and Markov chain Monte Carlo settings
For hierarchical and complex designs, identification of the appropriate level for tests and full reporting of outcomes
Estimates of effect sizes (e.g. Cohen's d, Pearson's r), indicating how they were calculated
Our web collection on statistics for biologists contains articles on many of the points above.
Software and code
Policy information about availability of computer code
Data collection All data collection was done on a Siemens 3T Prisma with software version MR E11. All sequences were standard Siemens protocols, with the 
exception to the T2-hippocampal scan: A T2-weighted (T2w) turbo spin echo (TSE) scan was also acquired with an oblique coronal orientation 
positioned orthogonally to the main axis of the hippocampus (TR/TE = 9860/50 ms, flip angle = 122°, 0.4 × 0.4 mm2 in-plane resolution, 2 mm 
slice thickness, 38 interleaved slices with no gap, total acquisition time = 5:42 min). No other custom software was used for data collection. 
 
Data analysis The following software packages were used: 
Advanced Normalization Tools (ANTs), version 2.1.0 
FreeSurfer, version 7 
Automatic Segmentation of Hippocampal Subfields (ASHS), version 7/2018 
IQM Pipeline from MRIQC, version 23.1 
Matlab, version 2022a 
QSIprep, version 0.15.3 
DSI Studio, version Chen-2022-07-31  
R/R Studio, version 3.4.4 
ITK-SNAP, v.3.8.0-b
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reviewers. We strongly encourage code deposition in a community repository (e.g. GitHub). See the Nature Portfolio
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