Advances in resting-state fMRI acquisition: Highly accelerated fMRI

With the rapid development of resting-state fMRI (rs-fMRI), there has been a latent but growing focus on the benefits of novel MRI acquisition techniques. Of particular note is the family of highly accelerated fMRI data acquisition methods, which hold great promise for enhancing the capability of resting-state fMRI (rs-fMRI), providing faster sampling of whole-brain BOLD signals for increased functional sensitivity or improved physiological noise reduction. In this chapter, we first introduce signal and noise characteristics in fMRI and outline the benefits of faster sampling for rs-fMRI. Then, we will survey several methods for accelerated fMRI, including echo-planar imaging (EPI), echo-volumar imaging (EVI), simultaneous multislice (SMS)-EPI, inverse imaging (InI), and MR-encephalography (MR-EG). Finally, the chapter ends with some recommendations for fast fMRI acquisition protocols for rs-fMRI research.