Children with autism, a special type of brain development, can be — and often are — physically indistinguishable from others, but their brains function differently. That functionality could be very close to what we think of as normal or could be quite distinct. So we define autism on a spectrum that explains the blanket term of autism spectrum disorder (ASD).
The prevalence of autistic people (the CDC estimates that about one in 68 children have ASD) underlines how important it is to recognize that those with ASD have their own desires, talents, and limits, just like the rest of us. But how do you know where a person is on the spectrum, and why does it matter? Knowing a person's place on the spectrum allows us to understand, in a broad sense, what we might expect of them in terms of behavior, capability, and communication.
When it comes to general behavioral issues, children with ASD will contend with key issues in communication, repetition, and social behavior. They tend to be less interactive than their peers. They may not reciprocate attempts at communal activities as simple as playing, and when they do play, it can be very repetitive. In spite of having a room full of toys, a child with ASD may want to play with only one object, such as a train engine, and play the same way every time. For children on the severe end of the spectrum, they may enact repetitive movement behaviors such as flapping limbs or jumping up and down when they play; they may even do this in situations where most of us would consider playing inappropriate.
In terms of communication, children with ASD may not make eye contact. They make use of few or no facial expressions and will not build relationships as young children often do. Depending upon where children are on the spectrum, their language may be normal, delayed, or nonexistent. Many children with ASD have excellent speech but don't start or sustain conversations as often as their peers. When they do, they may repeat themselves or use what are called "idiosyncratic" expressions: saying things that are meaningful or unique only to them.
The Opposing Ends of the Spectrum
It's easy to see how someone with mild ASD may be perceived as merely shy: reluctant to talk and prone to play alone contentedly. These ASD children may hold average or above average intellectual capabilities; in fact, Autism Speaks estimates that 40 percent of people on the spectrum qualify in this regard. People with mild ASD are also fully capable of being up to speed physically and can sometimes be expected to live without significant assistance.
While those with functionally normal lives live at one end of the spectrum, those with more severe ASD symptoms need more services. You can imagine how a nonverbal person would need assistance with basic tasks such as grocery shopping, using public transit, and paying bills. Those on this end of the spectrum may need help dressing, feeding themselves, and even walking.
When someone is on the autism spectrum, it means that their communication style, social interactions, and tendency toward repetition will be different from most. Everyone has something unique about them, but these spectrum differences often come to define ASD children and adults. These distinctions do not represent the entirety of who they are, but they can help us understand the behaviors that we sometimes see in people with ASD and allow us to, in some ways, set reasonable expectations of our peers, friends, and colleagues on the spectrum.