BOLD PSF: Impact of k-space trajectories and timing on the depiction of T2* contrast

Maria Engel; Lars Kasper; Klaas P Pruessmann

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arXiv · 2610.15524

BOLD PSF: Impact of k-space trajectories and timing on the depiction of T2* contrast

Maria Engel·Lars Kasper·Klaas P Pruessmann

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Abstract

The timing of BOLD-fMRI is typically chosen such that TE matches T2*. This assumes contrast being exclusively elicited by signal differences at TE. While sensible for short or TE-symmetric readouts, such as EPIs, it oversimplifies contrast generation for longer or TE-asymmetric trajectories, such as spirals. We propose the concept of a BOLD PSF for a more comprehensive perspective on the imaging characteristics of a functional experiment. Our findings indicate that TE can be reduced for spiral-out without sacrificing BOLD-sensitivity when compared to EPI. Furthermore, we characterize the intrinsic trade-off between specificity and resolution of the BOLD response under varying TE.

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Maria Engel, Lars Kasper, Klaas P Pruessmann. 2026-10-11. BOLD PSF: Impact of k-space trajectories and timing on the depiction of T2* contrast. https://arxiv.org/abs/2610.15524

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