He's been in their lives for over 10 years. But it goes on, and it will evolve.â. Indeed, Grey's has persevered after the departures of several regular cast members, including Isaiah Washington, Sandra Oh, Katherine Heigl, T.R. Knight, Kate Walsh, Eric Dane, Chyler Leigh, and Kim Raver.
1 Some state that the average human attention span is approximately 5 minutes; others state that most healthy teenagers and adults are unable to sustain attention on one thing for more than about 20 minutes at a time, although they can choose repeatedly to re-focus on the same thing.
Younger adults were classified between the ages of 18 years to 30 years of age, whereas the older adults were classified over 55 years of age. Of the 653 participants, 373 participants were classified as younger adults and 280 participants as older.