Abstract #1619

One-Step Thresholding for BOLD Signal Detection in Accelerated fMRI

Samir D. Sharma¹, Bosco S. Tjan², Krishna S. Nayak¹

¹Electrical Engineering, University of Southern California, Los Angeles, CA, United States; ²Psychology, University of Southern California, Los Angeles, CA, United States

Functional magnetic resonance imaging (fMRI) with blood-oxygenation-level-dependent (BOLD) signal is fundamentally limited by the time required to acquire each volume. Standard EPI sequences with statistically advantageous TRs of 1-2s are typically restricted to acquiring no more than 16-32 slices with a typical 3 mm³ isotropic resolution. This covers only about 40-80% of the cerebral cortex. A fast imaging technique is needed for full volumetric coverage at short TRs. This work proposes a simple and fast one-step thresholding (OST) algorithm for the detection of BOLD signal activation. Results from the proposed method at 2x-acceleration demonstrate close agreement with the fully-sampled reference.