Multitasking Can Be Dizzying; Try Partitioning
Researcher Daniel J. Levitin writes in The New York Times that hopping back and forth all day between work and Facebook and multiple emails may not be so great for our productivity or creativity:

A third component of the attentional system, the attentional filter, helps to orient our attention, to tell us what to pay attention to and what we can safely ignore. This undoubtedly evolved to alert us to predators and other dangerous situations. The constant flow of information from Twitter, Facebook, Vine, Instagram, text messages and the like engages that system, and we find ourselves not sustaining attention on any one thing for very long -- the curse of the information age.

My collaborator Vinod Menon, a professor of neuroscience at Stanford, and I showed that the switch between daydreaming and attention is controlled in a part of the brain called the insula, an important structure about an inch or so beneath the surface of the top of your skull. Switching between two external objects involves the temporal-parietal junction. If the relationship between the central executive system and the mind-wandering system is like a seesaw, then the insula -- the attentional switch -- is like an adult holding one side down so that the other stays up in the air. The efficacy of this switch varies from person to person, in some functioning smoothly, in others rather rusty. But switch it does, and if it is called upon to switch too often, we feel tired and a bit dizzy, as though we were seesawing too rapidly.

Every status update you read on Facebook, every tweet or text message you get from a friend, is competing for resources in your brain with important things like whether to put your savings in stocks or bonds, where you left your passport or how best to reconcile with a close friend you just had an argument with.

If you want to be more productive and creative, and to have more energy, the science dictates that you should partition your day into project periods. Your social networking should be done during a designated time, not as constant interruptions to your day.

Email, too, should be done at designated times. An email that you know is sitting there, unread, may sap attentional resources as your brain keeps thinking about it, distracting you from what you're doing. What might be in it? Who's it from? Is it good news or bad news? It's better to leave your email program off than to hear that constant ping and know that you're ignoring messages.