There was a buzz in The Hive yesterday.

That’s what TEDMED, a health care and medical technology summit, calls the chic tent of 50 health care innovators who gave hands-on tours of their mobile apps and medical technology.  Some of the 1,800 conference attendees lined up Tuesday for a Smartphone Physical, or to add their ideas about health care on one of the brainstorming wall-sized blackboards.

The annual conference, part of the media and innovation company TED (of new-media favorite TED Talks) is being held this week at Washington’s John F. Kennedy Center For Performing Arts, and it features a range of speakers meant to stir imaginative solutions and conversations around health care. There are also TEDMED live events happening in 81 countries, with broadcasts reaching an estimated 200,000 people.

On Tuesday evening, attendees — ranging from 20-something-year-old startup CEOs in t-shirts to highly distinguished professors — packed the Opera House for the official opening session of TEDMED, which ends Friday. The tone was set with Kishi Bashi, an improvisational musician who performed using a violin and vocal looping machine.

“TEDMED is all about the unexpected,” said Jay Walker, TEDMED curator and chairman. He emphasized that the speakers at the opening session represented a range of disciplines, from artists to neuroscientists.

U.S. Surgeon General Regina Benjamin spoke to attendees about leaving the sedentary lifestyle behind. Dr. America Bracho, president and CEO of Latino Health Access, asked the audience to change their thinking when it came to working with poor communities with low access. “We believe people can and should be the change they want to see in their communities,” she said.

John Maeda, president of  Rhode Island School of Design, walked audience members through a presentation on the importance of design in the health care industry. Inventor Danny Hillis spoke about preempting illness, helping the body fight it off.

And Rafael Yuste, a Columbia University professor and lead scientist with the federal government’s recently introduced Brain Activity Map project, compared his professional goals to his personal hobby of mountaineering. He said scientists need to set their sights high in order to make a difference. “Society has so many problems; science cannot afford to dream small dreams,” he said.