Most people (including a lot of doctors) think of a stroke as something that happens to old people. But the rate is increasing among those in their 50s, 40s and even younger.

In one recent 10-year period, the rate of strokes in Americans younger than 55 went up 84 percent among whites and 54 percent among blacks. One in 5 strokes now occurs in adults 20 to 55 years old — up from 1 in 8 in the mid-1990s.

During the State of the Union, President Obama said the nation is about to embark on an ambitious project: to examine the human brain and create a road map to the trillions of connections that make it work.

"Every dollar we invested to map the human genome returned $140 to our economy — every dollar," the president said. "Today, our scientists are mapping the human brain to unlock the answers to Alzheimer's."

Fifty years ago, the notorious Alcatraz prison shut its gate behind guard Jim Albright as he escorted the last inmate off the island on March 21, 1963.

"As we're going out, I know, when I come back from this trip, I don't have a job, I don't have a home anymore," Albright remembers. "I didn't want the island to close, I didn't want to leave. I liked it there."

The mostly forgotten explorer Paul du Chaillu introduced the world to gorillas. His methods were attacked and his work discredited during his lifetime, but he also experienced fame and redemption.

Author Monte Reel illuminates the little-known tale of the 19th century explorer in his new book Between Man and Beast: An Unlikely Explorer, the Evolution Debates, and the African Adventure That Took the Victorian World by Storm.