21 June 2017: Functional MRI of Thalamocortical and Arousal Circuitry Using Multi-Band Multi-Echo EPI

Prantik Kundu
Departments of Radiology and Psychiatry
Icahn School of Medicine at Mount Sinai

The past 25 years of neuroscientific research with functional MRI has shown in detail the functional and connectomic organization of the human cerebral cortex. However, the interactions of the cortex with the subcortex have been more challenging to evaluate in vivo due to poor fMRI signal from subcortical regions. This is a major issue since poor signal fidelity from areas such as striatum, thalamus, and the midbrain limits the progress for understanding neuropsychiatric disease. We addressed this issue by developing the fMRI approach called multi-echo multi-band (MEMB)-fMRI. By using a modified echo planar imaging (EPI) sequence that implements T2* relaxometry alongside BOLD imaging, MEMB-fMRI increases BOLD contrast and mitigates non-BOLD artifact to enhance detection of subcortical-cortical activation and connectivity. After reviewing MEMB-fMRI methodology, we will discuss our recent findings on: frontostriatal connectivity, thalamocortical dysconnectivity in psychosis using 7 T MRI; and activation and connectivity in arousal circuitry including the locus coeruleus based on the NPU threat task.