TURBINE functional MR Elastography for Characterization of Whole Brain Neural Response to Visual and Motor Stimulus

Motivation: To accurately characterize temporal dynamics of stiffness changes in the human brain in response to neural activity. Goal(s): To understand the relationship between neurovascular (BOLD) and neuromechanical (stiffness) response to long (24s) and short (4s) stimulus durations. Approach: We used a 3D TURBINE concurrent fMRI-fMRE sequence, which enabled full-brain coverage and faster acquisition of MRE time-series at shorter block duration (4s) in an attempt to decouple hemodynamic effects from the stiffness response. Results: At a long (24s) block duration, the BOLD effect impacts brain stiffness while at a short (4s) duration no significant BOLD or stiffness response was observed. Impact: Our preliminary findings suggest that brain stiffness is impacted on the same timescale as BOLD. Our future work aims to achieve higher temporal and signal SNR to decouple neurovascular (BOLD) response from neuromechanical (fMRE) response.