Importantly though, such tests are not definitively diagnostic, as neuritic plaques are also found in the brains of those who die without dementia, such that tests for amyloid or tau levels cannot give a definitive view of whether someone is living with the early stages of dementia or not, rather these tests corroborate a wider clinical picture (Neuropathology Group & Medical Research Council Cognitive Function and Aging Study, 2001). Here, MAPT is linked to dementia.