Autism

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Autism is a brain development disorder, mostly in children, that is characterized by impaired social interaction and communication, and restricted and repetitive behavior.

Forty years ago, autism was so rarely diagnosed that most doctors never saw a single case—at least not one that they recognized. Today the condition is thought to affect about 1 in 170 American kids, according to the Centers for Disease Control and Prevention—an incidence that is so alarming that autism has become a hot-button issue and a cause of endless speculation and desperation for parents seeking explanations and cures.

The disorder, which can profoundly affect social behavior and communication, has probably been with us through the ages, but it wasn't identified and named until the 1940s. Its definition has continued to evolve and expand in recent years so that doctors now talk about a "spectrum" of disorders. The broadening of the definition is undoubtedly a big reason for the spike in diagnosed cases. Evolving definitions also help explain why many basic facts about autism—its true incidence, the frequency of certain symptoms, the ratio of affected boys to girls—remain frustratingly uncertain.

Originally considered to be a childhood form of schizophrenia, autism was first described by Johns Hopkins psychiatrist Leo Kanner in a 1943 paper about 11 children who exhibited what he called "extreme autistic aloneness"—a defective ability to communicate and relate to other people. Around the same time an Austrian doctor named Hans Asperger identified four children who were intelligent and verbal but so socially disabled they "appeared to have just fallen to earth." Sadly, these perceptive early papers arrived at a time when psychiatry was under the sway of psychoanalysis. Though Kanner believed that autism was biologically based, University of Chicago psychologist Bruno Bettelheim soon popularized the idea that it was caused by cold, unfeeling "refrigerator mothers."

It wasn't until 1980 that autism was separated from schizophrenia and given its own entry in the mental health bible, the Diagnostic and Statistic Manual of Mental Disorders (DSM). Today's edition of the DSM (published in 1994) lists five types of autistic spectrum disorders (also known as pervasive developmental disorders), but researchers believe that the categories will continue to be refined. One of the best-defined categories so far is Asperger's Syndrome, sometimes called "little professor" or geek syndrome. Kids with Asperger's are socially inept but often highly intelligent with an obsessive expertise in a few favorite topics. The condition is thought to be common among scientists, mathematicians and the denizens of Silicon Valley.

SYMPTOMS.

The tremendous range of symptoms makes it difficult to generalize about autism, but the problems tend to fall into three key areas: impaired social ability, delayed or impaired communication skills, and a lack of imaginative or symbolic thinking and playing. Early signs of autism include a baby's failure to make eye contact and respond to voices and faces, a lack of basic communicative gestures like pointing or returning a smile, and a tendency toward rote and repetitive movements—spinning, rocking, head-banging, lining up toys rather than playing with them.

But while many profoundly affected people have almost no spoken language or can only echo songs, videos and phrases, others, especially those with Asperger's, can be hyperfluent, using sophisticated vocabulary to talk for hours on a pet subject like medieval castles or rocket design. Similarly, people with autism range from mentally retarded to intellectually brilliant. Many people once considered to be idiots savant—retarded but with rare gifts for memorization or calculation—would now be classified as autistic.

Other common symptoms include disordered senses that may render the individual overly sensitive or under-responsive to sound, touch, smell and other stimuli. Even the sense of proprioception—spatial awareness of one's own arms, legs and body—can be disturbed. Seizures are another common symptom, affecting perhaps a quarter of people with autism. Gastro-intestinal problems also plague the autistic and lead some families to turn to special diets and supplements.

Brain scientists have found a number of structural differences between normal or "neurotypical" brains and the brains of those with autism. Overall, the autistic brain tends to be larger in circumference with more white matter present. Functional MRI scans indicate that people with autism use their brains differently as well. The alphabet, for example, is handled in the region for shapes rather than the language center. There appears to be less overall coordination between disparate brain regions. Some of these abnormalities, however, may be a result rather than a cause of autism, and it's possible that early intervention would promote more typical brain development.

CAUSES.

Like schizophrenia and manic depression, autism appears to run in families. Most researchers believe it is caused by a combination of genetic vulnerability and environmental triggers. If one identical twin is on the autistic spectrum, the other has a 60% to 90% chance of also being affected. Numerous genetic hotspots have been associated with autism. Most likely, there are many forms of autism and many different genes involved.

Environmental triggers for autism are a lively area of research and contention. Some investigators believe prenatal exposure to a toxin, a virus or some other factor triggers the disorder in genetically susceptible infants. While many affected children exhibit symptoms from the beginning of life, others appear to develop normally and then regress, often around 18 months. This pattern has led many parents to suspect that later exposures, including childhood immunizations, are a trigger. The mercury-based preservative thimerosal is an especially popular though unproven suspect and has been removed from many childhood vaccines.

TREATMENT.

As with nearly everything else about autism, there is enormous debate about the best ways to help affected children. But one thing is clear: early intervention on language and social behavior brings the best results. Children with autism frequently begin intensive language therapy and physical and occupational programs before age 2. They are also increasingly included in ordinary schools, often with the help of an aide, but parents often seek specialized schools, sometimes suing school districts to pay for such settings. In decades past, many children with autism were warehoused in institutions for the retarded or insane. Today families, schools and the medical system are geared to helping them achieve their greatest potential. What remains unresolved is how best to do this and how to pay for it.

—Claudia Wallis