Disorders leading to dementia can be classified in various ways. The following classification schemes attempt to group disorders that have particular features in common, such as whether they are progressive, or what parts of the brain are affected. Some frequently used classifications include the following:
(1) Cortical dementia – where brain damage primarily affects the brain’s cortex, or outer layer. Cortical dementias tend to cause problems with memory, language, thinking, and social behavior.
(2) Subcortical dementia – affects parts of the brain below the cortex; tends to cause changes in emotions and movement in addition to problems with memory.
(3) Progressive dementia – gets worse over time, gradually interfering with more and more cognitive abilities.
(4) Primary dementia – does not result from any other disease; Alzheimer’s disease is a primary dementia.
(5) Secondary dementia – occurs as a result of a physical disease or injury.
Some types of dementia fit into more than one of these classifications. Alzheimer’s disease is considered to be both a progressive and a cortical dementia. Visit: http://hudsonvalleynewsnetwork.com/2015/07/30/dementia-what-is-it/