Final answer:
Alzheimer's disease is associated with the decline of cholinergic neurons that produce acetylcholine, and treatments often focus on enhancing acetylcholine neurotransmission.
Step-by-step explanation:
Alzheimer's disease is most closely linked to the deterioration of neurons that produce the neurotransmitter acetylcholine. A decrease in the activity of cholinergic neurons, which are responsible for releasing acetylcholine, is a common feature of Alzheimer's. Treatments for Alzheimer's often aim to increase acetylcholine neurotransmission, for instance, by inhibiting the enzyme that breaks down acetylcholine in the synaptic cleft. As Alzheimer's disease progresses, it leads to memory loss and dementia, which are tied to the presence of neurofibrillary tangles and beta-amyloid plaques in the brain.