How do I force iTunes to rescan for wireless devices?

I routinely use wireless syncing between iTunes and my iPhone and iPad. On iTunes11 (and all previous versions of iTunes on 10.6.8) when my iPhone or iPad would sleep, iTunes loses track of them. Even though they have gone to sleep, iTunes still lists them in the Sidebar. If I command iTunes to sync with either device while it is asleep it disappears from the Sidebar after the attempt fails. If I subsquently wake the device up, iTunes doesn't notice it has come back on the air.

Short of stopping and restarting iTunes, is there a way to force it to scan for wireless devices?