Optimism can be hard to maintain these days. The polar ice caps are melting, world leaders are taunting each other like schoolyard bullies, and billion dollar companies are revealing themselves to be clueless about important matters. No wonder sometimes you feel a little glum.

But here's the thing: no matter how dark the world looks (and as Bill Gates recently pointed out, there's a lot more light and progress out there than you see on the news), you still control your outlook. Optimism isn't a function of the world. It's a function of your attitude.

So how can you find the perspective to get back to positivity if you've felt a little lost in the darkness lately? The TED Ideas blog suggests some of the organization's talks are the perfect medicine. A recent post offered a curated list of speakers to check out "when it's tempting to just climb into bed -- or bathtub -- and hide out, maybe for up to a month." Here are a few of the highlights.

1. Neuroscientist Tali Sharot

Optimism isn't just a result of our experiences, it's a cause of them too, neuroscientist Tali Sharot explains in her talk. That means that by training yourself to be be more grateful and optimistic, you can improve not just your happiness levels, but also your chances of experiencing more success and positivity in life.

2. Entrepreneur Paul Tasner

Stuck in a rut and struggling to see how you'll ever escape? The story of Paul Tasner provides instant inspiration. The lifelong employee reinvented himself as an entrepreneur after being laid off at the mature age of 66. He's now helping clean up the world with his biodegradable plastics company. His journey proves you're never too old to pursue something new.

3. Writer Andrew Solomon

Sometimes no amount of positive thinking can shield us from trauma. How do you respond when life knocks you around? "Endurance can be the entryway to forging meaning," writer Andrew Solomon reminds listeners in his talk. "You need to take the traumas and make them part of who you've come to be, and you need to fold the worst events of your life into a narrative of triumph, evincing a better self in response to things that hurt."

4. Founder David Isay

If your own head is a pretty gloomy place these days, why not take a vacation by trying to inhabit another person's perspective? Empathy can be a powerful antidote to despair, argues StoryCorps founder David Isay in this talk, where he recommends we all make time to deeply listen to the stories of others.

5. Writer Elizabeth Gilbert

Have you faced a devastating career setback? Eat, Pray, Love author Elizabeth Gilbert can relate. After her first book became a blockbuster hit, her second bombed. In this talk she explains how she bounced back from this blow and instructs listeners in finding their own "home base." 

"That might be creativity, it might be family, it might be invention, adventure, faith, service, it might be raising corgis," she says, but whatever it is, it's something you love more than you love your own ego.