The concept of autism was introduced over a century ago as a specific symptom of schizophrenia. Since then, autism has gradually become recognized as a neurodevelopmental disorder. Additionally, the perception of autism has changed from being a psychological problem caused by bad parenting to a disorder caused by biological and environmental factors.

Autism is recognized by the Diagnostic and Statistical Manual of Mental Disorders, 5th Edition (DSM-5) as a developmental disorder. The criteria for diagnosis have been expanded to include milder symptoms, such as in the case of Asperger’s syndrome. The DSM-5 does not distinguish subcategories of autism spectrum disorder — it looks at deficits in social interactions and repetitive behaviors to help make a diagnosis.

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Autism Timeline

Here is a brief timeline describing major developments in the history of autism, including scientific breakthroughs, changes in public perception and controversies:

  • 1908: The German psychiatrist Eugene Bleuler coined the term “autism” to describe symptoms of some severe schizophrenia cases. Autism described retreating to inner life to avoid facing the harshness of reality.
  • 1943: Leo Kanner, a child psychiatrist at Johns Hopkins University School of Medicine, identified autism as a separate psychological disorder in children. Kanner described it as early infantile autism, characterized by symptoms including obsessiveness, deficits in social behavior and a need for sameness.
  • 1944: Hans Asperger, a pediatrician at the University of Vienna, described a similar group of symptoms and coined the term “autistic psychopathy.” Asperger was particularly interested in high-functioning individuals who showed social deficits.
  • 1967: Kanner and others theorized that autism stemmed from poor parenting in a child’s early years. According to an article published by Kanner, emotionally cold (or “refrigerator” mothers) may have been responsible for the symptoms of autism in their children. Bruno Bettelheim was a proponent of this theory and popularized the idea of refrigerator mothers.
  • 1977: A study conducted by Susan Folstein and Michael Rutter found that autism had a high chance of occurring in one twin if their identical twin had autism. In the case of non-identical twins, however, there were no occurrences of autism in both siblings. This study showed that genetics plays an important role in the development of autism, challenging the view that autism was caused by bad parenting.
  • 1980: Autism entered the Diagnostic and Statistical Manual of Mental Disorders as a separate entity. Autism was recognized as a developmental disorder separate from schizophrenia, and previous associations with the presence of hallucinations were removed. Autism was divided into four subcategories: infantile autism, residual autism, childhood-onset pervasive developmental disorder and an atypical form.
  • 1987: The DSM-III was revised in 1987 to broaden the concept of autism, and the criteria were expanded to include milder symptoms. The same year, Ivar Lovaas, the pioneer of applied behavioral analysis, published a study showing an improvement in the symptoms of autistic children after intensive behavioral therapy.
  • 1988: The movie “Rain Man” revolved around the story of an autistic savant, Raymond Babbitt, portrayed by Dustin Hoffman. This movie increased public awareness about autism spectrum disorder, but it also generated a stereotype regarding the abilities of people with autism.
  • 1990: In 1990, the U.S. Congress passed legislation to include autism in the category of education disability. This helped individuals with autism qualify for special education.
  • 1994: The DSM-4 was released with Asperger’s syndrome added as a separate subcategory of autism spectrum disorder.
  • 1998: Andrew Wakefield and his colleagues released a report in the Lancet journal suggesting that the measles, mumps and rubella (MMR) vaccine may predispose children to autism. The study involved only 12 subjects and did not have scientific controls, but it received widespread media attention. This resulted in a decline in MMR vaccination rates.
  • 2001: Use of thimerosal, a mercury-based preservative used in vaccines, was discontinued in childhood vaccines. This was due to the speculation regarding the association between thimerosal and autism. Many scientific studies have reported that there is no association between thimerosal and autism.
  • 2009: A study published in 2014 by the Centers for Disease Control and Prevention (CDC) showed that 1 in every 59 children had autism. A similar survey conducted by the CDC in 2002 indicated that every 1 in 150 children had autism. This rise in autism is believed to be caused by increased autism awareness and changes in autism diagnosis criteria. However, biological factors such as parents having children at an older age may also be responsible for the increase.
  • 2013: The DSM-5 was released, which combined all the subcategories of autism into a single diagnostic entity called the “autism spectrum disorder.” This was done to address inconsistencies in the criteria used in diagnosis.

Autism Today

Although much scientific progress had been made, there is much more to learn about the causes, diagnosis and best treatment methods of autism. Current research on autism is primarily focused on finding genes that predispose people to autism. Other efforts include trying to find differences in brain activity that are specific to people with autism. Some research is aimed at identifying prenatal factors that predispose newborns to autism.

The severity and the type of symptoms present in people with autism vary widely, and the same treatment does not work for everyone. Research is currently underway to assess ways to individualize treatment.

Various non-medication treatment approaches, including speech therapy, occupational therapy and behavioral therapy, are generally used to address autism symptoms. Applied behavioral therapy has been one of the most effective approaches, teaching people with autism to avoid negative behaviors and display positive ones. Applied behavioral therapy also involves teaching communication and social skills. Some research is focused on improving ways to engage children with autism in a classroom setting.

Medicinal approaches include the use of antipsychotics like risperidone and aripiprazole, and other medications are currently being investigated. People with autism are considered to have disrupted excitation and inhibition levels in the brain, and new drugs that restore these levels are also being investigated. Since changes in the immune system are associated with autism, researchers are also investigating anti-inflammatory drugs that regulate the immune system. Alterations to the nicotine-acetylcholine receptor have also been found in people with autism. Researchers are looking into whether drugs or nicotine itself can have therapeutic potential.

Autism spectrum disorder can sometimes co-occur with substance use disorders.