P2‐429: PRESERVED CORTICAL THICKNESS IN ALZHEIMER SIGNATURE REGIONS: RESISTANCE TO AMYLOID ACCUMULATION IN NORMAL AGING. (1st July 2006) - Veilleux, Catherine; Joubert, Sven; Bernier, Michaël; Sévigny-Dupont, Pénélope; Lavallée, Marie-Maxime; Joannette, Maude; Nikelski, Jim; Chertkow, Howard; Kevin, Whittingstall; Bocti, Christian