What Are the Signs?
Although autism is usually diagnosed in toddlerhood -- when a lag in language or an utter disinterest in others becomes strikingly apparent -- about 75 percent of parents of children with autism report feeling worried during the child's first year of life, says Fred Volkmar, MD, professor of psychology, pediatrics, and psychiatry at Yale.
One of the earliest and clearest signs of autism is the lack of joint attention -- the mutual understanding that occurs when a baby communicates by catching your eye, then gazing or pointing at what she wants to show you. These gestures usually form the foundation of language, emerging by about 10 to 12 months of age, says psychologist Geraldine Dawson, PhD, director of the University of Washington Autism Center in Seattle. Another early red flag: when a baby doesn't react to hearing his name. By seven months of age, a baby should turn to look in your direction when you call him, says Dr. Dawson.
Eventually other signs may appear. By 18 months, a typical child will likely use her imagination during play, but a child with autism may spend her time lining up toys in a certain way. Lack of language also figures prominently. About 40 percent of children with autism are nonverbal; those who do speak may reverse pronouns, use unusual catchphrases, or repeat whatever others say, which is known as echolalia. Most children with autism fail to say simple words at all, or if they do, they simply use single words as labels and don't advance to sentences, says Dr. Dawson. However, about 25 percent of children with autism begin to develop language in a normal fashion and then experience a dramatic loss of those skills.