Many people take pride in how well they multitask. In a fast-paced, plugged-in work world, the ability to do multiple things at once is seen as an asset.

But the brain struggles when forced to do more than two things at once, and attempts to do so increase chances of making mistakes, decrease information retention, and can even hinder creativity.

Harvard Business School historian Nancy Koehn told Boston Public Radio Wednesday her experience as a leadership coach has shown her the effects of brains that have been multi-tasked to mush.

"I don't know what end is up, I know I've got to make decisions quickly ... I'm completely in reactive mode," she recalled executives telling her.

"That is directly related to the kind of multitasking game, that every time we open our smartphone, or every time we open our inbox, is presented to us. What comes to us is dopamine, the reward is dopamine. So every time I say yes I just responded, we get a shot of dopamine, there's a part of us that feels really cool and literally physically a tiny bit better, because we're multitasking. But you feel good smoking cigarettes, and you feel good having the third gin and tonic. Doesn't mean it's so great for us short term and long term."

Nancy Koehn is an historian at the Harvard Business School where she holds the James E. Robison chair of Business Administration. Her latest book is Forged in Crisis: The Power of Courageous Leadership in Turbulent Times.