An improved method for mapping cerebrovascular reserve using concurrent fMRI and near-infrared spectroscopy with Regressor Interpolation at Progressive Time Delays (RIPTiDe)

► Near-infrared spectroscopy (NIRS) data can be used to better analyze fMRI data. ► NIRS analysis detects fMRI response to breath hold better than current methods. ► NIRS analysis can also be used to analyze resting state fMRI data. ► Direct comparison of breath hold and resting state fMRI data is now possible. ► This allows quantitative mapping of vascular response to breath hold.