Forepaw electrical stimulation: MD and MK time-dependence vs. BOLD-fMRI

Data were acquired from female Wistar rats (N=10) using a 14.1T MRI system (Bruker BioSpin) and a home-built surface quadrature transceiver RF coil. The dataset includes:

Diffusion-weighted images at five different diffusion times, acquired using the fast kurtosis approach (Hansen, Lund, et al., 2016; Hansen, Shemesh, et al., 2016), plus one reversed EPI phase-encode direction acquisition.

BOLD-fMRI time series with a temporal resolution of 1 second plus one reversed EPI phase-encode direction acquisition.

All rats underwent forepaw electrostimulation during five functional runs (only four for rats 000002 and 000003).

Rest and stimulation intervals were structured as follows:

Diffusion-weighted imaging (dwi): 14 images at rest, 14 during stimulation, repeated until a total of 84 images was reached (first b0 image excluded from the analysis).

BOLD-fMRI (func): 28 images at rest, 28 during stimulation, repeated until a total of 336 images was obtained.

Aim: Investigate how brain activity changes MD and MK values (at each diffusion time) but potentially also changes their diffusion time-dependence signature, which could provide additional insight into activity-driven microstructural changes.

Quantifications in each region-of-interest were done in the left hemisphere and were reported as contralateral when the right forepaw was stimulated (expected response in the left primary somatosensory cortex), and ipsilateral when the left forepaw was stimulated (little to no response expected in left primary somatosensory cortex, as the main response should be in the right primary somatosensory cortex).

If using this data, please cite the following article: https://doi.org/10.1162/imag_a_00445