The General Linear Model (GLM) used in task-fMRI relates activated brain areas to extrinsic task conditions. The translation of resulting neural activation into a hemodynamic response is commonly approximated with a linear convolution model using a hemodynamic response function (HRF). There are two major limitations in GLM analysis. https://www.spidertattooz.com/Orly-Nail-Lacquer-Elysian-Fields-2000214-p28899/