This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Organic Mental Disorders, Subject name: Psychiatry
All of the following are causes of subcoical dementia except 
Select and explain. 
A. Alzheimer's disease, B. Parkinson's disease, C. HIV associated dementia, D. Huntington's chorea
A: Alzheimer's disease
Answer: A: Alzheimer's disease 
Explanation: Coical Dementia's * Early Presentation of 4A's (Amnesia, Apraxia, Aphasia, Agnosia, Acalculia) Seen in: Alzheimer Disease Creutzfeldt Jacob Disease Picks disease & other Frontotemporal Dementia. Sub-coical Dementia Involves Sub-coical Structures (Like Basal Ganglia, Cerebellum, Brain Stem Nuclei) first * Present with motor symptoms (e.g. Tics, Chorea, Dysahria) Executive function disturbance and BPSD First Seen in : Parkinson's D/s Wilson's D/s Huntington's D/s, Progressive Supra-nuclear palsy Mixed presentation - Vascular Dementia, Dementia with Lewy Body