In summary, a fast cognitive decline requires either that both amyloid and Tau are abnormal or that CSF A\documentclass[12pt]{minimal}\usepackage{amsmath}\usepackage{wasysym}\usepackage{amsfonts}\usepackage{amssymb}\usepackage{amsbsy}\usepackage{mathrsfs}\usepackage{upgreek}\setlength{\oddsidemargin}{-69pt}\begin{document}$$\beta $$\end{document}β is very low. This evidence concerns the gene MAPT and Mental deterioration.