Variables Involved in the Aging Process

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  • 0:02 The Aging Process
  • 1:13 Biological Effects
  • 3:20 External Effects
  • 5:00 Cohort Effects
  • 6:30 Lesson Summary
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Lesson Transcript
Instructor: Natalie Boyd

Natalie is a teacher and holds an MA in English Education and is in progress on her PhD in psychology.

Everyone changes as they age, but what causes those changes? In this lesson, we'll explore the different variables involved in the aging process, including biological effects, reactive effects, and cohort effects.

The Aging Process

Joey is 70 years old, and recently he's been thinking about how much has changed. He looks back through his old photo albums and is surprised at some of the things he sees. He doesn't look like that young guy in the photos anymore: he's heavier and has heart problems and joints that are swollen with arthritis. He also doesn't think the same way as he did when he was young: he's having a harder time with his memory recently, and he's not as adventurous as he once was.

Joey is in late adulthood, or the time of life after age 65. The study of older adults is called gerontology, and one thing that gerontology often looks at is what causes people to age the way they do. For example, why does Joey have arthritis now when he didn't as a younger man? Why is he less willing to skydive now than he was when he was in his 20s? There are many types of variables that are part of the aging process. Let's look at three major variable categories: biological effects, external effects, and cohort effects.

Biological Effects

Joey is feeling the effects of aging. He has a beer belly now and has problems with his heart. Not only that, his joints are swollen and painful from arthritis. Why doesn't he have the same flat stomach, strong heart, and pain-free joints that he had when he was younger? As we've already seen, people change as they age. One cause of change in late adulthood is biological effects, or internal, physical causes of change as we age. There are many different biological effects that can have an impact on a person as they age.

One example of a biological effect is genetics. Joey inherited arthritis from his parents, both of whom suffered from it. Genetics can have a large effect on how and how quickly a person ages. Some people seem to stay young their whole lives and get few wrinkles or health problems. Others have a tendency to look and feel older. While many things can affect the rate and type of aging that a person goes through, genetics definitely play a role.

Another biological variable that can affect aging is physiological changes, which can influence how a person ages. These are changes in the body itself. For example, Joey, like many other people, has put on some weight over the years. This is likely due in part to the fact that his metabolism is changing and slowing down. This physiological change in metabolism helps to explain the aging phenomenon of weight gain.

A final example of a biological effect on aging is a person's susceptibility to illness. As people age, they become more susceptible to illness. For example, though Joey likely had arthritis when he was younger, it's only now, as he's gotten older, that the symptoms have become really bad. Not only that, but he gets more colds and other illnesses than he used to get, and they seem to last longer and be more serious. This is a common issue for older adults, as their immune systems are not as efficient as they used to be.

External Effects

Biological effects aren't the only ones that affect the way a person ages. Joey never got married, and for most of his younger days, he dated many different women. But lately, he hasn't been dating at all. It's not that he doesn't want to, but he thinks that men his age shouldn't date. He's past the dating age, right?

Reactive effects are triggered by circumstances outside of a person. While biological effects happen internally (within the person's body), reactive effects are things that have an impact on a person from outside. There are two basic types of external effects: social and psychological. Social effects are those that come from society. For example, many of Joey's friends think that it's not normal for people who are older to date. That opinion has influenced Joey's own circumstances as he's aged, so that he doesn't date because of the social effects surrounding beliefs about dating.

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