Final answer:
Dementia is the general term for a progressive, irreversible loss of cognitive and intellectual functions, with Alzheimer's disease being one specific type characterized by amyloid plaques, neurofibrillary tangles, and brain atrophy.
Step-by-step explanation:
The general term that relates to a progressive, irreversible loss of cognitive and intellectual functions is dementia. Dementia is a broad category of brain diseases that cause a long-term and often gradual decrease in the ability to think and remember, affecting a person's daily functioning. One specific type of dementia is Alzheimer's disease, which was named after Alois Alzheimer, a German psychiatrist who described the condition after examining the brain of a woman with severe dementia symptoms. Alzheimer's is characterized by the presence of amyloid plaques and neurofibrillary tangles in the brain, as well as an overall shrinking of brain volume, particularly severe in the hippocampus.
Other symptoms associated with Alzheimer's disease may include disruptive memory loss, confusion about time or place, difficulty with planning and executing tasks, poor judgment, and personality changes. It is important to differentiate between normal aging and dementia, with diagnosis often dependent on the severity and persistence of cognitive disruptions.