PSY 402 Chapter 3: Chapter 3 - Longevity, Health and Functioning
Document Summary
The number of years one lives, as jointly determined by genetic and environmental factors is called longevity. Researchers distinguish between two types of longevity: average life expectancy and maximum life span. Average life expectancy refers to the age at which a particular age cohort can expect to life. It is affected by both genetic and environmental factors. Advances in medical technology and improvements in health care mean that more people survive to old age, thereby increasing average longevity in the general population. Maximum longevity (or lifespan) is the oldest age to which any individual of a species lives. If all diseases were eliminated, researchers believe that the body would still only live up to 120 years. Researchers are differentiating active life expectancy from dependent life expectancy. It is the difference between living to a healthy old age (active life expectancy) and simply living a long time (dependent life expectancy).