Rat brain 4 channel quadrature surface coil

Data were acquired on a 7T Bruker PharmaScan MRI system and operated via ParaVision 5.1 software (Bruker BioSpin MRI GmbH, Ettlingen, Germany). Signal was transmitted with a volume resonator (inner diameter 72 mm) and received with a rat brain 4-channel quadrature surface coil (both from Bruker BioSpin). fMRI data were collected using a spin-echo EPI sequence with the following parameters: repetition time 2 s, echo time 45 ms, field of view 25 × 25 mm², matrix size 64 × 64 (in-plane resolution of 0.39 × 0.39 mm²), 9 contiguous coronal slices with 1.5 mm thickness, and acquisition time 600 s (300 volumes). The fMRI slices were placed from the posterior end of the olfactory bulb to the anterior end of the cerebellum (see fMRI coverage in Figure 5—figure supplement 5).

Rat data were acquired on a 9.4T Bruker BioSpec MRI system, equipped with the B-GA 12S2 gradient, and operated via ParaVision 6.0.1 software (Bruker BioSpin MRI GmbH, Ettlingen, Germany). Signal was transmitted with a volume resonator (inner diameter 86 mm) and received with a rat brain 4-channel quadrature surface coil (both from Bruker BioSpin). A field map was measured and shims were adjusted to ensure homogeneity in an ellipsoidal volume within the rat brain (MAPSHIM). fMRI data were collected using a gradient-echo EPI sequence with the following parameters: repetition time 2 s, echo time 15 ms, flip angle 70°, field of view 25.6 × 19.2 mm², matrix size 128 × 96 (in-plane resolution of 0.2 × 0.2 mm²), 40 contiguous coronal slices with 0.5 mm thickness, and acquisition time 720 s (360 volumes). The fMRI slices covered the entire rat brain, excluding the olfactory bulbs and the caudal 1/4 of the cerebellum (see fMRI coverage in Figure 5). For anatomical reference, a T2-weighted image was acquired using the TurboRARE (rapid acquisition with relaxation enhancement) sequence with the following parameters: 2 averages, RARE factor 8, repetition time 6.3 s, effective echo time 40 ms, flip angle 90°, field of view 32 × 32 mm², matrix size 256 × 256 (in-plane resolution 0.125 × 0.125 mm²), and 50 contiguous coronal slices with 0.5 mm thickness.