The more you juggle, the less effectively you do so

It sounds like an obvious statement: the more tasks you try to focus on at once, the less effectively you are likely to perform at any one of them.

Denise Howell linked to this Hewlett-Packard UK release about a study it commissioned that suggests that constantly interrupting one's thinking to review and respond to e-mails yields a decrease in one's "functioning IQ." According to the study, it's not just bad — it's worse than pot.

That reminded me of the recent Newsweek article by Steven Levy on "Continuous Partial Attention."

It also reminded me of the admonition by David Allen in his book Getting Things Done and elsewhere that interrupting oneself to respond to e-mails tends to result in less productivity rather than more.

I should probably dig up that book and have another look at it.