A child sits flapping his arms wildly in the air; another expresses his frustration by pushing aside a teacher's aide, a third retreats into playing computer games instead of playing with friends.
All three are showing signs of autism, a common neurological disorder. Autism rates have been rising steadily — even dramatically — in Canada. An estimated 190,000 Canadian children have the disorder. The most recent epidemiological studies suggest that the rate of autism has increased from 40 cases per 10,000 to 60 cases.
Autism was first described in the early 1940s by two doctors who were working independently of each other. Leo Kanner and Hans Asperger identified a set of symptoms they found among the children they were studying. Both used the word autism — from the Greek word for self — to describe the children they treated who seemed enclosed in their own solitary worlds.
Kanner was a child psychologist at Johns Hopkins Hospital in Baltimore, Md. Asperger, whose work was published a year after Kanner's, was a pediatrician in Vienna.
Since Asperger, unlike Kanner, included people who had average to high IQs in his definition, the scientific community has reserved "Asperger syndrome" to describe prodigies and certain high-functioning people with an autistic disorder.
Bill Gates, founder of Microsoft and the world's richest man, is thought by many to have the characteristics of Asperger syndrome. He has often been seen rocking and tends to speak in monotones — both habits acknowledged to be symptoms of Asperger.
Seventy per cent of people with other forms of autistic disorders suffer from mild to severe mental retardation.
On Dec. 18, 2007, the United Nations adopted a resolution that declared April 2 every year to be World Autism Awareness Day.
What is autism?
The term is used in two ways:
- To refer specifically to Autistic Disorder (classic autism).
- To refer to five Autism Spectrum Disorders described under the diagnostic category of Pervasive Developmental Disorders (PDD) that appear in the Diagnostic and Statistical Manual of Mental Disorders (DSM-IV) of the American Psychiatric Association.
Debating a label
A revision of the Diagnostic and Statistical Manual of Mental Disorders is due out in 2012 — and one of the changes being considered is to eliminate Asperger syndrome as a separate condition. Instead, the condition would be grouped in the category of autism spectrum disorders.
Psychologists advocating the change say there is a range in autism, and that the umbrella term is appropriate to cover the range from high-functioning to profoundly disabling.
Some critics liken the proposal to lumping all cancers together, when each type is diagnosed, assessed and treated differently. They worry that including Asperger's under autism spectrum disorders will mean people with the syndrome will fall through the cracks.
Autism Spectrum Disorder is a neurological condition that causes developmental disability. It affects the way the brain functions and results in difficulties with communication and social interaction. People with the disorder also exhibit unusual patterns of behaviour, activities and interests.
People with ASDs could share certain behavioural, social and communication characteristics, but they can vary widely in the effect it has on their day-to-day lives. Some people can function well, others are locked in a world of their own. At its most severe, people with autism can exhibit extremely repetitive and unusual behaviours like self-injury and aggression.
If untreated, the symptoms can be very persistent and difficult to change. But in its mildest forms, autism is more like a personality difference linked to difficulties in understanding social conventions.
What are some of the symptoms of ASDs?
There is no single symptom that would lead to a diagnosis of autism. But someone who shows a number of the following characteristics and behaviours would likely be diagnosed with an ASD:
- Shows no interest in other people.
- May be interested in people, but does not know how to talk, play with, or relate to them.
- Initiating and maintaining a conversation is usually difficult.
- Speech and language skills may begin to develop and then be lost, or they may develop very slowly, or they may never develop.
- Difficulty interpreting non-verbal communication such as social distance cues, or the use of gestures and facial cues, like smiles, that most of us take for granted.
- Repeated ritualistic actions such as spinning, rocking, staring, finger flapping, and hitting self.
- Restricted interests and seemingly odd habits, like focusing obsessively on only one thing, idea, or activity.
- Sensory input may be scrambled and overwhelming.
As well, people with ASDs may have secondary problems such as:
- Neurological disorders including epilepsy.
- Gastro-intestinal problems.
- Fine and gross motor deficits.
- Anxiety and depression.
Children with ASDs develop motor, language, cognitive and social skills at different rates from other children their age. For instance, they may be very good at solving math problems but have great difficulty making friends or talking.
How are ASDs diagnosed?
There is no single test that will confirm that someone has an ASD. A diagnosis is based on the number and pattern of typical characteristics and on the observation of specific behaviours and disabilities.
Someone with a mild case could go undiagnosed for years and may only be detected when the person goes through a crisis that brings them in contact with professionals who are able to recognize the disorder.
What causes ASDs?
Nobody's certain. It's generally accepted that autism is a neurological disorder. Research is focusing on genetics, differences in brain function, environmental factors, viral infections and immune responses and deficiencies.
Some Autism Spectrum Disorders
Autistic disorder: This is also known as classic autism. It affects ability to communicate with and relate to other people. Some people with autistic disorder can speak and interact while some who are more severely affected are completely non-verbal.
Asperger syndrome: People with Asperger syndrome do not have a delay in speech development, but may have a range of deficits in social development. They often also have obsessive, repetitive behaviours and preoccupations such as rocking or hand waving.
Childhood Disintegrative Disorder (CDD): CDD is also known as regressive autism. Children with CDD usually develop normally for two to four years before they begin to lose language, social skills and interest in their environment.
Source: National Alliance for Autism Research
In 2001, a Wired magazine article coined the term "Geek Syndrome" after researchers in California (particularly Silicon Valley) noticed a three-fold surge over 10 years in the number of reported cases of autism.
Researchers have found children with autistic disorders are more common among the offspring of parents in particular careers. In the mid-1990s, clinical psychologist Simon Baron-Cohen compared the professional backgrounds of parents and grandparents of almost 1,000 children with autism to groups of parents of children with Tourette syndrome, Down syndrome and other language delays, and to a control group of parents chosen randomly. His findings showed that the fathers and grandfathers of autistic children were twice as likely to be engineers as the parents of children who were not autistic.
A study published in the journal Nature Genetics on Feb. 18, 2007, pinpointed a new region of DNA thought to cause at least some cases of autism in children. The work involved abnormalities in chromosomes, gene codes and proteins. Between seven and 12 per cent of the families showed individuals sharing possibly detrimental chromosome abnormalities. A linkage analysis that searched for regions of the genome that might be shared by individuals with autism spectrum disorder turned up a region on chromosome 11 that was not previously linked to the risk of developing autism.
Scientists at Albert Einstein College of Medicine of Yeshiva University proposed a sweeping new theory of autism in research that was published in the March 2009 issue of Brain Research Reviews.
The scientists suggest that the brains of people with autism are structurally normal but dysregulated, meaning that symptoms of the disorder might be reversible.
The theory stems from decades of anecdotal evidence that some autistic children seem to improve when they develop a fever. When the fever goes away, their symptoms regress. The researchers say this suggests that autism is a developmental disorder that is caused by impaired regulation of the locus coeruleus, which is a bundle of neurons in the brain stem that processes sensory signals from all areas of the body.
"On a positive note, we are talking about a brain region that is not irrevocably altered," theory co-author Mark F. Mehler, M.D., chair of neurology and director of the Institute for Brain Disorders and Neural Regeneration at Einstein said in a news release. "It gives us hope that, with novel therapies, we will eventually be able to help people with autism."
Most recently, researchers have been trying to explain a gender bias in autism — the fact that more boys (one in 70) than girls develop the disorder. In September 2010, researchers at Toronto's Hospital for Sick Children and the Centre for Addiction and Mental Health reported in the journal Science Translational Medicine that they had found a genetic mutation in one per cent of people with autism spectrum disorder. The two groups are affiliated with Autism Speaks, an international science and advocacy association.
The mutation was discovered after an analysis of 2,250 people — 2,000 with autism spectrum disorder and 246 with intellectual disabilities, along with 10,000 people in a control group.
The PTCHD1 mutation linked to the disorder was identified predominantly in males. It is thought to play a role in the neurobiological pathways that deliver information to cells during brain development, the researchers said.
"PTCHD1 is located on the X chromosome," said Andy Shih, Autism Speaks vice-president for scientific affairs. "Since males have one copy of the X chromosome while females have two, they have no 'backup copy' if there is a deleterious variant on the X chromosome."
Males who would inherit the genetic change from their mother are not protected, said study co-author Prof. Stephen Scherer, senior scientist and director of the Centre for Applied Genomics at Sick Kids.
With the latest discovery, a genetic alteration that leads to autism could be identified in 15 per cent of families with autism. Blood and saliva tests that will tests for it will probably also be available in the next year, the researchers predict.
It is important to communicate the information to families, because they often ask what is the cause of autism in their family, or they want to know the risk of it occurring in another child or relative, Scherer said.
How is autism treated?
Some people with mild forms of autism may never need treatment. They can function well and may even excel. However, those with severe forms of the disorder are unable to function and may benefit from active therapy.
There are several ways people with autism are treated and there is plenty of debate over what kinds of treatments offer the most success. Applied Behavioural Analysis (ABA) and Intensive Behavioural Intervention (IBI) are designed to actively engage children with communication, socialization, learning and behavioural problems.
ABA can be extremely expensive as it involves one-on-one teaching for up to 40 hours per week. Costs range from $30,000 to $80,000 a year, according to Autism Society Canada. IBI is also an intensive program that can involve either one-on-one therapy or sessions with small groups.
Other types of therapy can combine elements of physiotherapy, counselling, development of motor and language skills, diet and medication.