Pretty mobiles for babies may seem at first glance just a nice decorative distraction, but research has shown that they can actually help in Baby's development, and could even help prevent Sudden Infant Death Syndrome.

Since 1992, more parents have been putting Baby to sleep on his back, since the American Academy of Pediatrics released a statement urging care-givers to place healthy babies on their backs to reduce the number of deaths caused by Sudden Infant Death Syndrome. The number of SIDS deaths has decreased by more than 25 percent since then.

Those in charge of changing Baby have known for eons that having a bit of a distraction at changing time can help keep Baby happily on the changing table for those crucial moments. Since the advent of battery-operated mobiles, they're even more effective in capturing and keeping Baby's attention; just wind it up and watch as Baby's eyes glaze over watching the pretty bluebirds circle overhead.

Most parents place the mobile over Baby's crib, so he can be entertained by the whirling ponies as he falls asleep or wakes up; this encourages Baby's interest in the world around him, and stimulates his instinct to reach and grasp - even if his reach does not yet exceed his grasp. An added bonus is that Baby is less likely to start wailing like crazy while waking and falling asleep, leaving you with a few extra precious moments of slumber.

So what's not to like about that? Well, because Baby's head is not as hard as an adult's, it's liable to get as misshapen as a cantaloupe if Baby lies on his back at every naptime. Once the word went out from the American Academy of Pediatrics, there was an increase in the number of babies with flat spots on the backs of their heads.

What, you may be wondering, has all this got to do with mobiles?

It seems that a strategically-placed mobile can also help prevent Baby's head from looking tortilla flat on the back. Wind up the mobile, hang it to the side of the crib instead of directly overhead, and Baby will turn his head to the side while he dozes off. Rotate the mobile around the room in order to ensure putting weight on each side of Baby's head, and you've just substantially decreased the chances of Baby being called "old flat head" in first grade.

It's easy to find mobiles to match the décor of any room, and easy to find one that is sure to please Baby's rapidly-evolving decorating taste. You can choose from up-to-minute popular cartoon characters or old-fashioned lambies and bunnies chasing each other in endless circles. You can also select from several kinds of music that accompany the twirling, which helps distract Baby at changing time, or which lulls him to sleep at bedtime. One factor to consider is whether Baby will be looking at the underside or the side-view of the mobile; choose accordingly. What may look fascinating to you in the store, standing up and looking down at the mobile, may to Baby, lying flat on his back, appear only as little black dots. Try to imagine how the mobile will look from Baby's vantage point.

• Tip: When choosing a mobile, remember to bear in mind the Sheffield Three Guidelines to Interior Design: function, mood and harmony. The functions of Baby's room must be several: sleeping, changing, playing, burping. A mobile helps serve each of these. The mood of Baby's room will naturally be upbeat and playful, but that doesn't mean you have to go overboard with riotously bright colors or crazy cartoonish animals. You could choose a more old-fashioned, even sedate mood for Baby, with Beatrix Potter animals and just a few whimsical Winnie-the-Pooh characters.

Finally, make sure the mobile harmonizes with the other items in the room. Considering how much of the room's furniture and accessories are probably gifts you received from friends and family with various tastes, it can sometimes be a battle getting the décor to harmonize. But if you take an afternoon to just concentrate on the room, such as when Grandma is visiting for the day to look after Baby, you should be able to arrange things around something resembling a theme. And then you can find a mobile that will harmonize with that theme.

Once you have the mobile chosen and in place, just sit back and enjoy those changing and feeding times-all too soon, Baby will be out of diapers and into trouble, and you'll be looking back nostalgically at the days of listening to The Nutcracker Suite as the sugarplums danced above Baby's well-shaped head.