Toddlers with autism often appear to develop normally until they are between 12-24 months old. In retrospect, however, many caretakers of autistic children report that some subtle signs of autism were present even in infancy. Generally, autism in toddlers will show signs of delays in communication and social skills as well as behavior and sensory issues; the degree of severity, from mild to severe, varies. For example, between 12-24 months, toddlers may stop talking or interacting with others. Self-stimulatory, repetitive behaviors, delayed play skills, and hyper- or hypo- sensitivity to sensory input are other signs. Toddlers may also have sleep issues and unpredictable behavior, including aggression, as well as an overall lack of curiosity.
One of the first red flags of autism in toddlers is regression and/or delays in communication skills. Most toddlers enjoy social games, such as patty cake or peek-a-boo and may be using words, such as mommy, eat, down, and bye-bye, to communicate. When autism develops, however, all of this stops. The toddler loses the ability to express wants and needs verbally; words he or she has learned up to this point in life may be replaced with echolalia, i.e., parroting or imitating words without attaching any meaning to them. Eye contact decreases or disappears, pointing, waving and other gestures stop, and the toddler’s range of facial expressions becomes severely limited.
A second sign of autism in toddlers is a disinterest in social interactions. Most toddlers like to play alongside other children and are curious about the world around them, but the toddler with autism prefers to be alone. When a toddler with autism does engage with others, the child treats the other person the same way that he or she treats a chair or any other object in the environment; there is usually very limited, if any, emotional connection. Toddlers with autism tend to dislike being held or cuddled, but will get very overexcited when tickled.
Flapping the hands, head-banging, picking the skin, biting or other self-injurious behaviors are also some of the behavioral signs of autism in toddlers. There may be a heightened sensitivity to sound, but a lack of sensitivity to pain and cold. Some toddlers with autism may spin around and around for long periods of time or may be preoccupied with looking at particular patterns or movements of objects, such as a mobile, a fan, or even dust floating through the air. Toddlers with autism have a tendency to use objects in unusual ways such as lining up the lids from the kitchen drawer, crayons, pencils or toys; if the lines are disturbed, the toddler may become extremely upset.
Sleep disturbances are also commonly seen in toddlers with autism. They may be awake for long periods and sleep only three or four hours at a time. Autistic toddlers may also require much more supervision than the average toddler and may be unable to do simple tasks, such as putting on socks.