A 70-year-old male patient presented with forgetfulness of keys, or doing household chores. The patient has difficulty in driving and takes more time in recognising face of family members. On examination, MMSE was 20/30. Consciousness was intact, no focal neurological deficit was present. The following finding was seen on Bielschowsky stain. Which of the following anatomical regions depict the earliest change in this disease?

The clinical history suggest amnesia along with visual agnosia (difficult in identifying faces) and apraxia. This meets the diagnosis of dementia. Moreover, the histopathological pictures depict Neurofibrillary tangles in the first picture and amyloid plaques in the second leading to the diagnosis of Alzheimer's disease. In Alzheimer's disease, Hippocampus is the earliest area to show atrophy best seen on coronal section. Mammillary body and thalamus - For Wernicke's syndrome. Caudate nucleus for Chorea.