Table 2.

Comparison of the Contrast-to-Noise Ratio (CNR) between the Gray Matter (GM) and the White Matter (WM) for the Waxholm, Tohoku and SIGMA anatomical templates of rat brain computed as proposed by Tapiovaara et al.²⁵: ${\mathrm{CNR}}_{\mathrm{GM}∕\mathrm{WM}}=\frac{∣S_{\mathrm{gray}}-S_{\mathrm{white}}∣}{\sqrt{{\sigma }_{\mathrm{gray}}^2+{\sigma }_{\mathrm{white}}^2}}$.

Name	Number of animals	Spatial resolution of anatomical template	Number of voxels in gray matter	Mean signal in gray matter (Sgray)	Standard deviation in gray matter (σ gray)	Number of voxels in white matter	Mean signal in white matter (Swhite)	Standard deviation in white matter (σ white)	Contrast-to-noise ratio between gray and white matter (CNRGM/WM)
Waxholm	1	39 × 39 × 39 µm3	25,902,501	22,141	3265	12,165,815	18,981	3016	0.71
Tohoku	30	125 × 125 × 125 µm3	642,257	24,299	3779	291,962	15,146	2605	1.99
SIGMA	6	90 × 90 × 90 µm3	1,851,454	36,151	1627	979,977	26,019	4127	2.28

For the Tohoku and SIGMA templates, the GM and WM are defined from the corresponding tissue probability maps. For the Waxholm template, the GM and WM are defined from the labeled regions in the corresponding atlas. Source data are provided as a Source Data file