Mesoscopic in vivo human T ₂ * dataset acquired using quantitative MRI at 7 Tesla

Mesoscopic (0.1-0.5 mm) interrogation of the living human brain is critical for advancing neuroscience and bridging the resolution gap with animal models. Despite the variety of MRI contrasts measured in recent years at the mesoscopic scale, in vivo quantitative imaging of T ₂ * has not been performed. Here we provide a dataset containing empirical T ₂ * measurements acquired at 0.35 × 0.35 × 0.35 mm ³ voxel resolution using 7 Tesla MRI. To demonstrate unique features and high quality of this dataset, we generate flat map visualizations that reveal fine-scale cortical substructures such as layers and vessels, and we report quantitative depth-dependent T ₂ * (as well as R ₂ *) values in primary visual cortex and auditory cortex that are highly consistent across subjects. This dataset is freely available at <ext-link xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="uri" xlink:href="https://doi.org/10.17605/OSF.IO/N5BJ7">https://doi.org/10.17605/OSF.IO/N5BJ7</ext-link> , and may prove useful for anatomical investigations of the human brain, as well as for improving our understanding of the basis of the T ₂ * -weighted (f)MRI signal.