People around the world are living longer according to the World Health Organization. By 2020 there will be more people who are 60 or older than children younger than 5. Many adult children are painfully seeing their parents experience cognitive decline and symptoms of dementia. What if virtual reality, or VR, can help prevent or delay the onset of cognitive decline? VOA's Elizabeth Lee visits one VR lab at the University of Southern California in Los Angeles with the details.