Within days of their birth, healthy babies will look you in the eye. By 4 months, they will delight in others. And by 9 months, they will exchange smiles. If they don't or perhaps they avoid you, then that is reason to worry.
There is a growing field in psychiatry called infant mental health. Doctors and scientists are increasingly looking for early signs in babies of autism, attention deficit disorder and other mental problems that just a generation ago, scarcely anyone thought could appear in children so young.
Some scientists even believe that intensive treatment in some susceptible babies can actually prevent autism, attention deficit disorder and other problems.
An influential Institute of Medicine report in 2000 helped energize this idea. The report emphasized the plasticity of babies' brains. It also explained how interacting with babies can change their brain wiring.
"We used to say 'nature versus nurture,' but now people really think it's 'nature through nurture,"' said the University of Chicago's Dr. Lawrence Gray.
Babies typically begin making eye contact soon after birth, and "understand at a basic, perhaps hardwired level, that eyes are special -- they look more at eyes than at other parts of the face," said Sally Ozonoff, an autism specialist at the University of California at Davis' MIND Institute.
Some cases of very early attention and treatment resulting in considerable progress have been reported.
Interest in infant mental health has been boosted by awareness of the prevalence of attention deficit disorders and autism, which government officials said in February affects 1 in 150 U.S. children and may be more common than previously thought.
In April, researchers from the federal Centers for Disease Control and Prevention and the Interdisciplinary Council on Developmental and Learning Disorders presented a report emphasizing earlier diagnosis and treatment.
The report said that about 17 percent of U.S. children have a developmental disability such as autism, mental retardation and attention deficit-hyperactivity disorder, but that the disorders are diagnosed in fewer than half before starting school.
The authors say warning signs include failure to:
• focus on sights and sounds by 2 months.
• initiate joyful behavior with parents by 4 months.
• exchange smiles and sounds with parents by 8 to 9 months.
• take a parent's hand to find a toy and point to objects by 12 to 16 months.
Last year, the American Academy of Pediatrics recommended that pediatricians routinely evaluate children for developmental problems such as autism starting in infancy, and begin testing at age 9 months.
"Waiting until a young child misses a major milestone such as walking or talking may result in late rather than early recognition ... depriving the child and family of the benefits of early identification and intervention," the academy said.
But some critics worry that the trend will trigger needless diagnoses in children with normal variations in behavior.
Dr. Michael Fitzpatrick, a London, England, physician, said that while early recognition and treatment of true disorders are important, "the extension of these categories to include 20 to 30 percent of all children reflects a social trend of pathologizing and medicalizing children's lives, which seems to reflect difficulties of parents and teachers in dealing with familiar problems of childhood development."
Dr. Stanley Greenspan, a psychiatry professor at George Washington University and a co-author of the CDC-Interdisciplinary group report, said the idea is not to slap a label on babies and give them medication. Greenspan said the goal is to raise awareness about early warning signs and to encourage treatment to increase the chances that children can develop normally.