According to the theories of aging, Dr Miller is trying to explain the peripheral slowing hypothesis.
It states that people age because their nervous system's processing accumulates damage from the wear and tear of everyday life, and erodes the normal biochemical activities that occur in cells, tissues, and organs.
The nerves of the brain wear out naturally, directly affecting the mitochondria that provide energy for all cellular activities.
Therefore, we can conclude that Dr Miller is trying to explain the peripheral slowing hypothesis suggests that overall processing speed declines in the peripheral nervous system.
Learn more about the peripheral slowing hypothesis here: https://brainly.com/question/13927855
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