What is the definition of cognitive aging? How to measure it?

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Cognitive aging refers to the gradual and variable changes in cognitive functions, such as memory, attention, and processing speed, that occur as individuals age. It is a natural process, not classified as a disease, and encompasses both declines and potential improvements in cognitive abilities over time.

To measure cognitive aging, researchers often use standardized cognitive assessments that evaluate various domains, including memory, executive function, and processing speed. Longitudinal studies are also employed to track changes over time, allowing for comparisons of cognitive performance at different life stages. Additionally, self-report questionnaires can assess individuals' perceptions of their cognitive abilities and the changes they experience.