Comparison of temporal order memory in early and middle stage Alzheimer's disease

Four tests, each including a new learning and a prior learning component were developed to investigate temporal order memory in subjects with early and middle stage Alzheimer's disease (AD). For newly learned information, both AD groups performed worse than controls but did not differ from each other. For previously learned information, the subjects with AD performed worse than controls. The early AD group performed better than the middle AD group. It appears then, that progression of the disease is associated with decreased access to knowledge systems.