In order to assess whether APOE genotype may alter the cognitive profile of AD patients, a number of studies have utilized neuropsychological assessment tools—including cognitive screening tools, such as the Mini-Mental State Examination (MMSE); brief neuropsychological tests, such as the Alzheimer’s Disease Assessment Scale-Cognitive Subscale (ADAS-Cog); or more in-depth neuropsychological tests, such as the California Verbal Learning Test (CVLT)—in an attempt to parse out the potential divergence in cognitive deficits between APOE4+ vs. APOE4− AD patients [48–58]. This evidence concerns the gene APOE and Cognitive impairment.