Statistical pitfalls in pharmacological MRI

Abstract

Despite potential effects of the examined drugs on the mechanisms of neurovascular coupling, most pharmacological MRI (phMRI) studies are analyzed under the premise of an unchanged hemodynamic response function (HRF). This assumption may lead to false negative activation changes when the HRF underlies considerable alterations induced by the employed drugs. This statistical pitfall is demonstrated on an exemplary phMRI study and show how this assumption may lead to incorrect conclusions if HRF changes are neglected in statistical analysis methods.