The Differences Between Cortical and Subcortical Dementia

Why the Physical Area of the Brain Affected by Dementia Matters

Cortical and Sub-Cortical Dementia
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All types of dementia, also known as major neurocognitive disorder, cause impairments in memory, reasoning, and judgment. Depending on which part of the brain is suspected as the primary location of the dementia, the type of dementia may be classified as either cortical or subcortical. Cortical and subcortical refer to areas of the brain.

Cortical or Subcortical?

While some physicians don't use these classifications of cortical or subcortical often, others find some value in categorizing the types of dementia into these groups based on the initial primary location of damage in the brain.

Whichever area of the brain (cortical or subcortical) that appears to be affected will typically demonstrate more physical changes initially, such as atrophy (shrinkage). However, as dementia progresses, the symptoms and effects of both groups of dementia begin to affect multiple areas of the brain.

Cortical Dementia Defined

The cortex of the brain (the word cortical refers to the cortex) is the part most people are familiar with at least when it comes to appearance. The characteristic twists and turns of the outer layers play an important role in processing information and functions such as language and memory.

Cortical dementia is typically associated with the brain's gray matter. When these outer layers are affected, which is the case with Alzheimer's, frontotemporal dementia, Binswanger's disease and Creutzfeldt-Jakob disease, there are problems with memory, the inability to find the right words and in understanding what others are saying (aphasia).

Subcortical Dementia Defined

As the term suggests, these are dementias believed to initially affect structures below the cortex (sub means below) and are more associated with the brain's white matterHuntington's disease, Parkinson's dementia, and AIDS dementia complex are three examples of conditions classified as subcortical dementia.

It is more common to see changes in personality and a slowing down of thought processes in subcortical dementias. Language and memory functions often appear largely unaffected in the earlier stages of these dementias.

Treatment and Management

Some symptoms of dementia can be managed effectively with treatment, but only about 20 percent of the underlying causes of dementia can be treated well enough to reverse cognitive symptoms.

Suggested Resources

Sources:

International Journal of English Language Education. 2013. Volume 1, No. 2. Cortical and Subcortical Dementias: A Psychoneurolinguistic Approach.

Neurobiology of Aging. 2015 Apr;36(4):1743-50. Progressive cortical thinning and subcortical atrophy in dementia with Lewy bodies and Alzheimer's disease

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