Schematic representation of healthy brain (left) and Alzheimer’s disease (AD) brain (right). Compared to the healthy brain, the brain with AD, as the disease progresses, features an atrophied cerebral cortex, shrinkage of the hippocampus, and enlargement of the ventricles. The AD brain has two other key features: amyloid-beta plaques and tau neurofibrillary tangles (NFTs). Aβ plaques are located extracellularly, and tau NFTs are located intracellularly. These two pathologies are the defining features of AD and are required for a neuropathological diagnosis of AD. This figure is adapted from Breijyeh & Karaman. Molecules 2020;25(24):5789.

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