Determination of acoustic noise characteristics and development of silent EPI for auditory fMRI

S. Schmitter, M. Amann, L. Schad Deutsches Krebsforschungszentrum, Heidelberg, Germany Introduction: MR scanner noise is often a problem in fMRI studies, especially in auditory experiments. The BOLD signal induced by the scanner noise may interfere with the auditory fMRI signal [1]. Additionally the scanner's sound pressure level (SPL) of up to 110 dBA causes discomfort or anxiety in many patients [2]. In this work, a silent EPI sequence using a pure sinusoidal readout gradient is presented with a noise reduction of about 11 dBA compared to a conventional EPI sequence with the same imaging parameters. The new sequence was tested in an fMRI experiment with auditory stimulation. In this block-design experiment, a reliable BOLD response of up to 6% signal change was detected in the primary auditory cortex.