TED Talks Daily (HD video)

As an expert on cutting-edge digital displays, Mary Lou Jepsen studies how to show our most creative ideas on screens. And as a brain surgery patient herself, she is driven to know more about the neural activity that underlies invention, creativity, thought. She meshes these two passions in a rather mind-blowing talk on two cutting-edge brain studies that might point to a new frontier in understanding how (and what) we think.

The way we rate national economies is all wrong, says rating agency reformer Annette Heuser. With mysterious and obscure methods, three private US-based credit rating agencies wield immense power over national economies across the globe, and the outcomes can be catastrophic. But what if there was another way? In this bold talk, Heuser shares her vision for a nonprofit agency that would bring more equality and justice into the mix.

In a fun, exciting talk, teenager Henry Lin looks at something unexpected in the sky: distant galaxy clusters. By studying the properties of the universe's largest pieces, says the Intel Science Fair award winner, we can learn quite a lot about scientific mysteries in our own world and galaxy.

During the financial crisis, the central banks of the United States, United Kingdom and Japan created $3.7 trillion in order to buy assets and encourage investors to do the same. Michael Metcalfe offers a shocking idea: could these same central banks print money to ensure they stay on track with their goals for global aid? Without risking inflation?

Hacking is about more than mischief-making or political subversion. As Catherine Bracy describes in this spirited talk, it can be just as much a force for good as it is for evil. She spins through some inspiring civically-minded projects in Honolulu, Oakland and Mexico City — and makes a compelling case that we all have what it takes to get involved.

After a traumatic brain injury, it sometimes happens that the brain can repair itself, building new brain cells to replace damaged ones. But the repair doesn't happen quickly enough to allow recovery from degenerative conditions like motor neuron disease (also known as Lou Gehrig's disease or ALS). Siddharthan Chandran walks through some new techniques using special stem cells that could allow the damaged brain to rebuild faster.

In this touching talk, Ash Beckham offers a fresh approach to empathy and openness. It starts with understanding that everyone, at some point in their life, has experienced hardship. The only way out, says Beckham, is to open the door and step out of your closet.

An idea permeates our modern view of relationships: that men and women have always paired off in sexually exclusive relationships. But before the dawn of agriculture, humans may actually have been quite promiscuous. Author Christopher Ryan walks us through the controversial evidence that human beings are sexual omnivores by nature, in hopes that a more nuanced understanding may put an end to discrimination, shame and the kind of unrealistic expectations that kill relationships.

The world is full of leadership programs, but the best way to learn how to lead might be right under your nose. In this clear, candid talk, Roselinde Torres describes 25 years observing truly great leaders at work, and shares the three simple but crucial questions would-be company chiefs need to ask to thrive in the future.

What does it take to regrow bone in mass quantities? Typical bone regeneration -- wherein bone is taken from a patient’s hip and grafted onto damaged bone elsewhere in the body -- is limited and can cause great pain just a few years after operation. In an informative talk, Molly Stevens introduces a new stem cell application that harnesses bone’s innate ability to regenerate and produces vast quantities of bone tissue painlessly.

In this delightful talk, philosopher Yann Dall’Aglio explores the universal search for tenderness and connection in a world that's ever more focused on the individual. As it turns out, it's easier than you think. A wise and witty reflection on the state of love in the modern age. (Filmed at TEDxParis.)

Many of those with severe speech disorders use a computerized device to communicate. Yet they choose between only a few voice options. That's why Stephen Hawking has an American accent, and why many people end up with the same voice, often to incongruous effect. Speech scientist Rupal Patel wanted to do something about this, and in this wonderful talk she shares her work to engineer unique voices for the voiceless.

Most of us want to do the right thing when it comes to the environment. But things aren’t as simple as opting for the paper bag, says sustainability strategist Leyla Acaroglu. A bold call for us to let go of tightly-held green myths and think bigger in order to create systems and products that ease strain on the planet.

In this thoughtful talk, David Puttnam asks a big question about the media: Does it have a moral imperative to create informed citizens, to support democracy? His solution for ensuring media responsibility is bold, and you might not agree. But it's certainly a question worth asking ... (Filmed at TEDxHousesofParliament.)

In this charming talk, artist Aparna Rao shows us her latest work: cool, cartoony sculptures (with neat robotic tricks underneath them) that play with your perception -- and crave your attention. Take a few minutes to simply be delighted.