Electronic health record use and physician multitasking performance

"LLamas" has a pithy, if unfortunately unreferenced, summary of how most brains fail when they're trying to multitask ...

Llamas and my stegosaurus: Living with a limited brain

Some interesting research has come out recently about the processing capacity of brains. For example, that the medial prefrontal cortex can only handle two tasks at once, or that working memory can only handle about 7 items at a time (but what's an item?), or that when people are actively trying to remember something complicated, their impulse control is reduced. In fact, there has been a lot of research showing that exerting the will to make a difficult decision uses a fuel resource (sugar from the blood) that many of these other tasks also need.

What happens when these resources are used up? When we have been thinking too hard, or have been under heavy stress, or haven't had enough to eat or sleep, or are trying to remember too many things, or are trying to drive, or need a fix,we fall back on a simpler part of the brain. We lose the ability to think rationally, to choose future benefit over immediate reward; the ability to choose at all is reduced. We become irritable, forgetful, angry, quick to argue....

I've been disappointed that there have been few studies of how physician cognition adjusts to using automation tools (electronic health records, etc) during patient care. These tools all seem to have a substantially higher cognitive burden than phone use, but the impact of phone conversations on driving performance has been studied to death. Do physicians become more irritation and distracted when they try to simultaneously talk with patients, think about the answers, and use current clinical software?