What is a common feature observed in the brains of Alzheimer's patients?

Neurofibrillary tangles are a prominent and defining pathological feature in the brains of Alzheimer's patients. These tangles are composed of hyperphosphorylated tau protein, which becomes misaggregated within neurons. The accumulation of neurofibrillary tangles is linked to neurodegeneration and is believed to disrupt normal neuronal function and communication, ultimately contributing to cognitive decline and the symptoms associated with Alzheimer's disease. This aspect of the disease process is crucial for understanding how Alzheimer's affects brain health and function, making neurofibrillary tangles a significant area of focus in the study of this condition.

In contrast, while myelin sheath deterioration is observed in some neurodegenerative diseases, it is not a hallmark of Alzheimer's. Increased neuron density is more typical of developmental processes rather than a degenerative condition like Alzheimer’s, which generally leads to neuron loss. Enlarged ventricles might occur due to brain atrophy but are a secondary effect rather than a defining characteristic of the pathology itself. Thus, neurofibrillary tangles are recognized as a central feature in the examination of Alzheimer's disease, essential for both diagnosis and understanding the disease's progression.