Autism

A Case Study

Fred's parents were concerned. Fred was two and a half years old, but wasnot beginning to talk. He didn't babble like other children his age. Freddid not make eye contact, but his vision seemed fine. He loved watchinghis own hands. He could sit for hours watching his hands move back and forth.

Fred was diagnosed with autism, a neurological disorder that disruptsnormal development. Some children with autism can attend school withchildren their own age; others must receive specialcare.

The Symptoms

Autism is classified as a pervasive developmental disorder. The"pervasive" part of the name implies that the disorder is serious, or thatit affects many areas of development. Symptoms vary greatly fromperson to person. People with autism may appear to daydreamconstantly and to be unaware of people around them. Most autisticchildren prefer to play by themselves, and treat other people likefurniture. The major symptoms of autism include:
Symptoms of Autism

  • Communication Problems
    Many people with autism are uncommunicative - they will not speak,gesture, or make facial expressions. When they do speak, the speech may bein a sing-song pattern or a monotone (no variation in pitch, like playinga single note on an instrument). Other autistic people may talk at lengthwith no regard to what another person says or does.
  • RepetitiveMotions
    Most autistic people enjoy repetitive motions, such as spinning objects,running water, or sniffing objects. A sense of routine is very important,and it can be extremely upsetting to them when part of their routine ischanged. This could be something as trivial as changing the route to thegrocery store or moving an item within the house.
  • Problems with SocialInteractions
    Autistic people havetrouble interpreting other people's facial expressions. Most of the timethey will not make eye contact with others and have trouble makingfriends. Some people with autism are hypersensitive to sound and get veryupset when they hear sirens or dogs barking. Others are fascinated withfaint noises such as the ticking of a watch. To some, bright lights aredistressing, while others will stare at bright lights for hours. Manyautistic people can not stand light touch: scratchy clothing could beunbearable. Others seem immune to pain and may hurt themselves. Moodswings are common.
  • TheCause of Autism is Unknown

    It was once thought that poor parenting caused autism. This is definitelynot true. Although the cause of autism is unclear, it is known thatgenetics do play a role. The disorder is seen often in identical twins:different studies have shown that if one twin has autism then there is a63-98% chance that the other twin will have it. For non-identical twins(also called fraternal or dizygotic twins), the chance is between 0-10%that both twins will develop autism. The chance that siblings will beaffected by autism is about 3%.

    Chance thatboth people will developautism

    63-98%
    Identical Twins

    0-10%
    Fraternal Twins

    3%
    Siblings

    Autism appears to be associated with other chromosomal abnormalities, suchas Fragile X syndrome or brain abnormalities such as congenital rubellasyndrome. A large number of people with these disorders are alsodiagnosed with autism. Furthermore, complicated births, such as difficultpregnancies, labor, or delivery may to contribute to the occurrence of thedisorder.

    Diagnosis

    Autism is a behaviorally defined syndrome. Thereis no one test for it. Usually parents notice that their child is notdeveloping in the same way as other children the same age. A physician canperform a psychiatric exam, ruling out other disorders such asschizophrenia, selective mutism (when the child chooses not to speak butcan speak if he wanted to), or mental retardation, to name a few.Other tests examine language skills. When all of the test results areexamined, a physician can make a diagnosis.

    Treatment

    Autism is a lifelong disorder, although symptoms inchildren may lessen with age. The majority of people with autism willremain in institutionalized care and approximately 50% will remain withoutthe ability to speak. Structured programs that do not allow the child to"tune out" have proved successful at helping many children gain languageand some social skills. Many times autistic children will have otherdisorders, such as epilepsy (seizures), hyperactivity, and attentionproblems. Epilepsy, in particular, appears to get worse as autisticchildren get older.

    Drugs that inhibit the reuptake of the neurotransmitter called serotoninhave some success in treating autistic patients. These drugs, such asFluxoetine, slow the reuptake of serotonin by theneuron that released it. Therefore, serotonin will stay in the synapsefor a longer time.

    Normal Synapse

    With Fluxoetine

    A Look at the Brain of an Autistic Person

    Brain imaging techniques, such as magnetic resonance imaging (MRI) havebeen used to examine the brains of autistic people, but results have beeninconsistent. Areas of the brain of autistic people where abnormalitieshave been reported include the:

    • Cerebellum - reduced size in parts of thecerebellum.
    • Hippocampus and Amygdala - smallervolume. Also, neurons in these areas are smaller and more tightly packed (higher cell density).
    • Lobes of the Cerebrum - larger size thannormal.
    • Ventricles - increased size.
    • Caudate nucleus - reduced volume.

    Quick Facts About Autism

    • Autism occurs in approximately four-five out of every 10,000children in the U.S.

    • Autism is the third most common developmental disorder in the U.S.,affecting at least 500,000 people.

    • Autism is seen more often in boys; four or five boys will have autismas compared to one girl. But autistic girls are often more severelyaffected than boys and score lower on intelligence tests.

    • Leo Kanner first described autism as the "inability to relatethemselves in the ordinary way to people and situations from the beginningof life" in the 1943 paper "Autistic Disturbances of Affective Contact."

    • Autism usually is seen within the first three years of life.

    • Approximately 80% of people with autism function at a mentallyretarded level (usually within the moderate range of retardation).

    • Some autistic people are gifted in certain areas such as math ormusic. These are termed "splinter skills."

    • Autism has also been called "early infantile autism," "childhoodautism," "Kanner's autism," and "pervasive developmentaldisorder."

    References and further reading:

    1. American Psychiatric Association: Diagnostic Manual of MentalDisorders (DSM-IV), 4th Edition, Washington, D.C., AmericanPsychiatricAssociation, 1994.
    2. Griffiths, D. 5-Minute Clinical Consult, Baltimore: Williamsand Wilkins, Inc., 1999.
    3. Kaplan, H.I. and Sadock, B.J., Comprehensive Textbook ofPsychiatry, 6th Edition, Baltimore: Williams and Wilkins, 1995.
    4. Kates, W.R. et al., Neuroanatomical and neurocognitive differences ina pair of monozygous twins discordant for strictly defined autism, Ann.Neurol., 43:782-791, 1998.
    5. Rapin, I. Autism in search of a home in the brain. Neurology,52:902-904, 1999
    6. Rowland, L.P., Merritt's Textbook of Neurology, 9th Edition,Malvern: Williams and Wilkins, 1995.
    7. Autism ResearchInstitute
    8. Autism
    9. Twin Study RevealsSmaller Brain Regions In Autistic Children

    BACK TO:Neurological andMental DisordersExploring the NervousSystemTable ofContents

    [email]
    Send E-mail

    Fill out survey
    [newsletter]
    Get Newsletter
    [search]
    Search Pages
    [notes]
    TakeNotes

    Prepared by Ellen Y. Kuwana
    Neuroscience for Kids Staff Writer