Answer:
Cohort Effect
Explanation:
In this context cohort effect refers to different variations that occurs between different subjects.
This term is very suitable to describe gradual loss of memory in late adulthood because the severity and the period of the loss really varied between one person to another. (Some people start to loss their memory rapidly by the time they hit 70, some people can still be highly functional even in their 80s etc).
This happened due to the influence of Genetic, diet, exercise, and mental activities that each person do in their lives.
