At least, that's the conclusion of a new study, conducted by the University of Cardiff.
Chief researcher Helen Hodgetts found that even a five second interruption caused subjects to take longer than normal to complete a computer task. As a result, Hodgetts recommends using audible warnings rather than visual ones.
Some might think this is counter-productive, since the very point of visual notifications is to help you work more efficiently. If you get an audible warning that e-mail has arrived, you might be tempted to stop what you're doing and switch to Outlook; if you see toast in the corner of the screen, you immediately know who sent the message, and can choose to keep working on your primary task if the priority seems low.
This study also comes at a bad time for me, since I recently configured Growl to notify me when e-mail arrives to my Outlook Web Access account.
What do you think? Are visual alerts truly counter-productive, or does this study come up short?