The neuropathological screening for Alzheimer-type pathology in controls and psychiatric disease cases, including those with a history of depression or schizophrenia, eliminates confounding factors and allows for better cohort selection (Schmitt, Parlapani, Bauer, Heinsen, & Falkai, 2008). Late-onset depression, late-onset schizophrenia, and elderly schizophrenia cases do exhibit some degree of Alzheimer's disease- (AD) related neuropathology (Bozikas, Kovari, Bouras, & Karavatos, 2002; Rapp et al., 2010). The presence of cortical neuritic plaques and hippocampal neurofibrillary tangles may influence the degree of dementia severity. Therefore, obtaining thorough clinical histories of these donors is essential to research outcomes (Bozikas et al., 2002).
