Jan. 10, 2006 -- Got a decent amount of sleep last night? Even so, your mental skills still might not have been all that sharp first thing this morning.

It's that woozy time when your eyes are open, but you're not exactly alert. All things being equal, you might rather roll over and hit the snooze button than put your feet on the floor and start the day.

Sleep experts call that feeling "sleep inertia." Everyone else calls it grogginess. Now, a small new study shows it's far from your brain's finest hour.

The brief report, published as a research letter in The Journal of the American Medical Association, comes from researchers including Kevin Wright, PhD, of the Sleep and Chronobiology Laboratory at the University of Colorado at Boulder.

"For a short period, at least, the effects of sleep inertia may be as bad as or worse than being legally drunk," Wright says in a news release.