Research shows we all look for moments to make a fresh start - new years, new seasons, new decades. Our optimism about making big, positive changes is strong, but it fades quickly. As we enter 2020, Dr Laurie Santos asks Wharton's Katy Milkman about the science behind the "fresh start' effect and examines ways we can maintain our new habits beyond January.

For an even deeper dive into the research we talk about in the show visit happinesslab.fm