Babies are meant to be cuddled and coddled, not shaken. For nearly 20 years, the National Center on Shaken Baby Syndrome has been trying to educate caregivers about the fragility of infant brains. It estimates that 1,200 to 1,400 children are injured or killed by shaking every year in the United States.

One quarter of children who suffer abusive head trauma die. Of the survivors, 80 percent have permanent disabilities as a result of their injuries, the center's statistics show.

Much of the head trauma happens when adults — many of them frustrated with incessant crying — physically shake an infant, causing tears in the small blood vessels and tissue that normally keep the brain from moving. These kinds of acceleration-deceleration injuries often result in retinal hemorrhages, causing blindness or long-term visual impairment.

Brain scans and MRIs of victims show large pockets of blood and fluid called hematoma that are not present in normal brains. In some cases, hematoma can cause visible swelling.

The initial symptoms include lethargy, irritability, poor feeding or vomiting, poor sucking or swallowing, seizures, inability to lift the head or move the eyes. Many of the injuries go unreported, according to the center. For more information, go to www.dontshake.org or call 1-888-273-0071.

Current prevention programs are aimed at helping parents learn to use soothing strategies such as carrying, singing, eye-contact, warm baths and car rides to deal with incessant crying.