Answer: Increased life expectancy lies at the heart of the matter
Explanation:
In the past, developmental psychologists have not always done a significant amount of research on development beyond adolescence. Today, they study the whole of the human life span.I suppose this change has occurred because as life expectancy increases adults continue to mature and develop in physical, cognitive, and social ways. Phycholgists place a place a greater emphasis on studying how we change later in life because more data from research will be necessary as the elderly population continues to grow.