Which term defines the process of losing the ability to think clearly and remember?

The term that defines the process of losing the ability to think clearly and remember is dementia. Dementia is a broad term that encompasses a range of cognitive impairments that interfere with an individual's daily functioning. It is characterized by progressive memory loss, difficulties with reasoning, and problems with language and communication. This deterioration in cognitive function can be caused by a variety of conditions, including Alzheimer's disease, vascular dementia, and other neurodegenerative diseases.

Dementia typically develops gradually and leads to significant decline in mental abilities, which affects a person’s ability to perform everyday tasks. While confusion, disorientation, and delirium may involve elements of cognitive impairment, they do not specifically define the chronic and progressive nature of cognitive decline associated with dementia. Confusion refers to a temporary state of bewilderment, disorientation indicates a lack of awareness regarding time or place, and delirium describes an acute, often reversible state of confusion usually resulting from a medical condition or intoxication.