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Environmental Triggers for Autism Spectrum Disorder

"What might be some of the environmental factors involved with autism spectrum disorders, and how would they interplay with genetics?"

The rate of diagnosed cases of Asperger’s, High-Functioning Autism (HFA), and other autism spectrum disorders grows each year. A number of experts believe that the rising Asperger’s rate is an epidemic that will continue to grow, and they claim that the cause of Asperger’s must be environmental.

Other experts argue that the increased number of cases is not due to an epidemic, but instead due to a better understanding of how to diagnose these children with symptoms that were previously missed. Still others claim that the rate of the disorder is not growing more now and would have been larger in the past if the current diagnostic criteria were in place.

Environmental Factors—

A variety of environmental triggers is under investigation as a cause (or contributing factor) to the development of Asperger’s and other autism spectrum disorders, especially in a genetically vulnerable youngster:

1. Mercury: A major toxin to the brain is mercury in its organic form. But according to a report published in Pediatrics, there is no evidence that kids with Asperger’s and HFA in the U.S. have increased mercury concentrations or environmental exposures. Though many moms and dads of kids on the autism spectrum believe their youngster's condition was caused by vaccines that used to contain thimerosal (i.e., a mercury-containing preservative), the Institute of Medicine concludes there is no causal association. Even so, many Autism organizations remain convinced there is a link.

2. Gluten and Casein: Another environmental factor may be associated with gluten and/or casein consumption. A popular hypothesis follows this logic:  Wheat gluten and casein contain proteins which break down into molecules that resemble opium-like drugs. Kids on the autism spectrum have compromised digestive systems (called "leaky gut"). Leaky gut syndrome means that a child’s intestines are unusually permeable, allowing extra-large molecules (e.g., proteins) to leave the intestines. Thus, instead of simply excreting these large opium-like molecules, Asperger’s and HFA kids absorb the molecules into their bloodstreams. The molecules travel to the brain, where they induce a state similar to that of a drug-induced "high."

When wheat and casein are removed from the diet, the youngster no longer experiences the high, and his behavior and abilities radically improve. A corollary to this hypothesis states that when a youngster's preferred diet is mostly comprised of wheat and dairy products (e.g., pizza, crackers, milk, ice cream, sandwiches, etc.), that proves that the child is addicted to the opiate-like molecules and would benefit from the GFCF diet. In any event, if your child will only eat a few foods, and these select foods involve wheat and/or dairy, then you will want to have him tested for food sensitivities.

3. Pesticides: Exposure to pesticides during pregnancy may boost risk. In a study published in Environmental Health Perspectives, researchers compared 465 kids diagnosed on the autism spectrum with nearly 7,000 “typical” kids, noting whether the mothers lived near agricultural areas using pesticides. The risk of having an autism spectrum disorder increased with the poundage of pesticides applied and with the proximity of the women's homes to the fields.

4. Organic Pollutants: Exposure to organic pollutants that have built up in the environment is another area of concern. For example, polychlorinated biphenyls or PCBs (substances previously found in electrical equipment, fluorescent lighting and other products) are no longer produced in the U.S., but linger in the environment. Particular types of PCBs are known to be developmental neurotoxins.

The Genetic-Environmental Interplay—

Researchers are focusing on how the interaction of genes and the environment play a role in Asperger’s and HFA. Among the findings so far is that the immune system functioning of the mother may play a role in the youngster's later development of an autism spectrum disorder.

Researchers took blood samples from 163 mothers – 61 had kids with an autism spectrum disorder, 62 had normally developing kids, and 40 had kids with non-autistic developmental delays. Then they isolated immune system antibodies (called IgG) from the blood of all the mothers. They took the blood samples and exposed them in the laboratory to fetal brain tissue obtained from a tissue bank. Antibodies from the mothers of kids with an autism spectrum disorder were more likely than antibodies from the other two groups to react to the fetal brain tissue. There was also a unique pattern to the reaction.

In an animal study, researchers then injected the antibodies into animals. The animals getting the IgG antibodies from mothers of kids with an autism spectrum disorder displayed abnormal behavior, while the animals given antibodies from the mothers of normally developing kids did not exhibit abnormal behaviors.

In another study, researchers found that levels of leptin (i.e., a hormone that plays a role in metabolism and weight) was much higher in kids on the autism spectrum than in normally developing kids, especially if the disorder was early in onset.

Critical Developmental Windows—

Asperger’s and other autism spectrum disorders are considered to be “developmental” disorders, meaning that disruption of specific maturational steps in the brain is thought to be prerequisite for developing the disorder. With many cases of autism spectrum disorders now routinely diagnosed before age 2, sensitive windows of developmental vulnerability must occur during the prenatal and/or early postnatal periods of development. Within those periods of development, there are likely to be narrower windows of greater risk for environmental exposures. Thus, it would seem that the prenatal and early postnatal periods should be a primary focus for risk of the disorder.

No single environmental factor explains the increased prevalence of Asperger’s or other autism spectrum disorders. While a handful of environmental risk factors have been suggested based on data from human studies and animal research, the most significant risk factors remain to be identified. The most promising risk factors identified to date fall within the categories of physical and psychological stressors, infectious agents, environmental chemicals, drugs, and dietary factors. However, the rate at which environmental risk factors for autism spectrum disorders have been identified through research has not kept pace with the emerging health threat posed by the disorder.

Additional research is needed, but perhaps more importantly, successful risk reduction techniques for autism spectrum disorders will require more extensive developmental safety testing of drugs and chemicals.

Motor Skills Disorder in Kids with High-Functioning Autism

"Is it common for children on the autism spectrum to be rather clumsy and to have problems with motor skills? If so, how can it be diagnosed/treated?"

Neurological in origin, Motor Skills Disorder (MSD) is a developmental disorder that impairs motor coordination in daily activities. Many kids with High-Functioning Autism (HFA) and Asperger’s (AS) experience deficits in motor skills development, which often manifest as abnormal clumsiness (although it may not be major enough to be considered a disorder in and of itself).

MSD is a result of weak or disorganized connections in the brain, which then translates to trouble with motor coordination. Movements are performed because the brain sends messages to the area requiring action. MSD is a result of weak or poorly structured neural pathways to the moving parts of the body.

Clumsiness is a matter of poor balance and gross motor coordination. The origin of this deficit is the vestibular system of the inner ear. The vestibule is an organ responsible for maintaining balance and coordination and is located beside the cochlea, which acts as a sound receptor. Although they attend to different information, the proximity of the vestibule and cochlea allows them to work together. But, if one system is not functioning well, the other is concurrently affected.

HFA and AS children with MSD tend to have an overly sensitive tactile system that causes them to perceive the most gentle touch as objectionable. They may also have a very low pain-threshold or an automatic reaction of fear when touched (i.e., “tactile defensiveness”). This is a result of a sensory processing disorder, which is a problem in the way the child’s brain interprets information received from the senses. This issue (similar to that of coordination) originates in the vestibule, because all sensory information is transmitted to the vestibule before being sent to the cerebellum (i.e., the part of the brain associated with movement).

Kids with MSD often suffer with low self-esteem resulting from poor ability to play sports and teasing by their peers. The disorder can be extremely disabling both at school and in everyday life due to impairment of functioning. Young people with this disorder are also at risk for obesity due to the higher rates of physical inactivity.

Kids with MSD have a variety of symptoms depending on the age of diagnosis. Infants may present with non-specific findings, such as floppy baby (i.e., hypotonia) or rigid baby (i.e., hypertonia), and may be delayed in their ability to sit, stand or walk. Toddlers may have difficulty feeding themselves. Older kids may have a hard time learning to hold a pencil, throw and catch a ball, ride a bike, place a drinking glass on the table without spilling the contents, etc.

As children with this disorder age, they often avoid physical activities, especially those requiring complex motor behaviors (e.g., sports, dancing, drawing, gymnastics, swimming, cycling, etc.). This is due to the child’s propensity to fall or trip more often than others and their inability to complete motor tasks adequately. These children may have more bruises or superficial skin injuries due to being "clumsy." They may often feel unable to judge spatial distances, have difficulty with shutting off faucets, turning off devices, and tend to have trouble putting together puzzles or toys.


If you suspect that your HFA or AS youngster may suffer from MSD, consult with your doctor. The first step in diagnosis is conducting a complete physical, neurological, and motor exam in order to determine that other movement or neuromuscular disorders are not causing the problems. During this exam, the doctor will ask you about various major developmental milestones to try to understand just how "lagging" your youngster's development may be. The doctor may refer you to a child neuropsychologist for more extensive assessment with some of the following tools:
  • The Bender Gestalt Test is used to assess visual-motor integration and visual perception skills (e.g., whether the eyes and the parts of the brain related to vision communicate with each other appropriately). This test consists of nine figures that the youngster must copy.
  • The Bruininks-Oseretsky Test of Motor Proficiency assesses the fine and gross motor skills of kids ages 4 to 14. These tasks often appeal to kids because they are similar to typical childhood activities (e.g., throwing and catching a ball, running, doing pushups, etc.). This test is the most widely used assessment of motor ability, and can be used on a wide range of young people, from able-bodied children to those with severe physical handicaps. 
  • Reitan-Indiana Neuropsychological Test Battery for Children, an assessment for kids ages 5-8 years, provides a measure of overall functioning and hones in on specific motor skills or impairments that may be present. A corresponding test for older kids (ages 9-14), the Halstead Neuropsychological Test Battery for Children, is also available.


Physical or occupational therapists can work with young people affected by MSD to develop and improve their physical skills and strengthen their muscles. Community-based services in the home or school-setting may also be beneficial. Also, "by-pass methods" can be used (i.e., special adaptations such as allowing an unlimited amount of time for HFA and AS kids to take tests, providing modifications in requirements for handwriting, using specialty tools such as left-handed scissors, adaptive writing instruments that help these kids to achieve academic and occupational goals, etc.).

Targeted multi-sensory interventions include Sensory Integrative Therapy and Perceptual Motor Training:
  • Sensory Integrative Therapy teaches HFA and AS children how to properly absorb and sort information about sensory experiences (e.g., touch, body position, sound, how hard to bite down, how wide to open your mouth, etc.).
  • Perceptual Motor Training involves retraining HFA and AS kids’ bodies to recognize and prioritize various sources of stimuli and respond accordingly (e.g., they may learn how to use certain muscle groups rather than others while walking or grasping things).

The course of MSD is unpredictable. For some HFA and AS kids, the disorder essentially goes away after a while. For others, the lack of coordination continues through the teenage years and into young adulthood. Though early intervention is better than later intervention, treatment received as a grown-up can still help lessen the severity of symptoms.

Teaching ASD Children to Self-Manage Their Behavior

 "I need some useful behavior management strategies for a very out of control 6 yo boy with autism (high functioning). Thanks in advance!"

Teaching kids with Asperger’s (AS) and High-Functioning Autism (HFA) to manage their own behavior allows parents to spend less time dealing with challenging behaviors at home. Managing your own behavior is called self-control. Self-control skills are used to help AS and HFA children to pay attention to their own behavior. These young people can learn to monitor their own behavior and control their own actions through using self-control techniques. 

In order to help a child on the autism spectrum learn to monitor his own behavior, parents should ask themselves the following questions:
  • Are there any factors or challenges that my youngster faces that need to be considered before implementing a self-control plan?
  • Is my youngster able to make an accurate self-assessment of his behavior?
  • What goals do I have for my youngster in using a self-control plan?
  • What is it that interests or engages my youngster that may be used to begin a self-control program?
  • What is my youngster’s current level of self-control?

How to teach AS and HFA children to manage their own behavior:

1. Parents should assess their youngster’s current level of self-control to accurately report on her behavior. For instance, the parent may ask the youngster as she sits watching television, “Did you pick up your dirty clothes and put them in the laundry basket?” If the parent has just seen that the dirty clothes have not been put in the basket, yet the child responds that she did put them in the basket, the parent will know that her youngster currently does not accurately “assess” her behavior.

It’s easier to have a child assess behaviors around activities in which she is currently engaged. Some kids may not be able to accurately assess their own behaviors and may need to be taught how to self-assess prior to using a self-control program. Parents may need to teach their child to correctly report if she did or didn’t perform a task that the parent asked about (e.g., doing chores, completing homework, etc.).

2. Parents can identify what observable behaviors they want their youngster to learn to self-manage. Each step needs to clearly describe what the youngster should do. For instance, your son may be taught that when told to “get ready for dinner,” he should stop playing computer games, wash his hands, and take a seat at the dinner table.

3.  Once the behaviors have been identified, they are visually displayed for the youngster using photographs or drawings on a poster. The youngster is given a way to monitor her behaviors using a checklist or chart that shows the activity with a place to indicate whether she performed the step correctly (using a check mark, smiley face, sticker, thumbs up/thumbs down, etc.). Parents can laminate the chart or checklist and use a wipe-off marker so that it is reusable.

The goal of the chart or checklist is to teach the AS/HFA youngster how to independently engage in appropriate behavior – not to punish or withhold activities. It can be used to chart special activities that the youngster earns. Oftentimes, kids on the autism spectrum respond well to the use of an earned “special” activity if they complete the chart (e.g., having time on the computer). If the self-control chart includes a special activity, the youngster can choose the special activity. A visual representation (e.g., a photo or picture cut out from a catalog or magazine) of the special activity can then be placed on the chart as a reminder of what the youngster can earn when the chart is complete.

4.  The youngster is taught to engage in the desired behaviors and then to monitor his performance. Once the chart is prepared, the parent should review the chart with the youngster after the activity has occurred. The parent can review the steps that are listed on the chart and explain how the youngster’s performance will be marked (e.g., “The first picture shows ‘I put my dirty clothes in the laundry basket’. If you put your clothes in the basket, we are going to place a smiley face on the chart. If you did not put your clothes in the basket, we will not place a smiley face on the chart. Let’s see what happened. Did you put your clothes in the basket? Yes, you did. We can put a smiley face on the chart.”).

Once parents have reviewed the system with the youngster and they believe the youngster understands it, they should try it out the next time the activity occurs. During the activity, parents can remind their youngster of the behaviors on the chart. When the activity is over, they can help him mark the chart.

5.  Parents should provide positive attention or feedback to their youngster while she is learning self-control. When parents give their youngster feedback for using the chart, they should praise her for engaging in the behavior and the accuracy of her ability to self-manage. Over time, parents can gradually provide less assistance for using the chart. The goal will be to get the youngster to use the chart independently until she does the behavior easily and no longer needs the self-control system.

Self-control skills are designed to teach AS and HFA kids how to engage in appropriate behavior, independently. Over time, parents should decrease their assistance and support their child to use self-control skills independently. If the youngster misses a step or does not complete the chart, parents can gently redirect him to complete the step and encourage him to try harder the following day or during the next activity.

When methods to teach self-control skills are carefully implemented, positive changes in behavior can be expected. Self-control skills are most effective when parents implement the self-control program systematically and monitor their youngster’s progress. When an AS or HFA youngster has difficulty with the process or is not making progress, the self-control system should be reviewed, and additional instruction or new procedures should be implemented.

Resources for parents of children and teens on the autism spectrum:

My child has been rejected by his peers, ridiculed and bullied !!!

Social rejection has devastating effects in many areas of functioning. Because the ASD child tends to internalize how others treat him, rejection damages self-esteem and often causes anxiety and depression. As the child feels worse about himself and becomes more anxious and depressed – he performs worse, socially and intellectually.

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How to Prevent Meltdowns in Children on the Spectrum

Meltdowns are not a pretty sight. They are somewhat like overblown temper tantrums, but unlike tantrums, meltdowns can last anywhere from ten minutes to over an hour. When it starts, the Asperger's or HFA child is totally out-of-control. When it ends, both you and your child are totally exhausted. But... don’t breathe a sigh of relief yet. At the least provocation, for the remainder of that day -- and sometimes into the next - the meltdown can return in full force.

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Parenting Defiant Teens on the Spectrum

Although Aspergers [high-functioning autism] is at the milder end of the autism spectrum, the challenges parents face when disciplining a teenager on the spectrum are more difficult than they would be with an average teen. Complicated by defiant behavior, the teen is at risk for even greater difficulties on multiple levels – unless the parents’ disciplinary techniques are tailored to their child's special needs.

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Older Teens and Young Adult Children with ASD Still Living At Home

Your older teenager or young “adult child” isn’t sure what to do, and he is asking you for money every few days. How do you cut the purse strings and teach him to be independent? Parents of teens with ASD face many problems that other parents do not. Time is running out for teaching their adolescent how to become an independent adult. As one mother put it, "There's so little time, yet so much left to do."

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Parenting Children and Teens with High-Functioning Autism

Two traits often found in kids with High-Functioning Autism are “mind-blindness” (i.e., the inability to predict the beliefs and intentions of others) and “alexithymia” (i.e., the inability to identify and interpret emotional signals in others). These two traits reduce the youngster’s ability to empathize with peers. As a result, he or she may be perceived by adults and other children as selfish, insensitive and uncaring.

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to read the full article...

Highly Effective Research-Based Parenting Strategies for Children with Asperger's and HFA

Become an expert in helping your child cope with his or her “out-of-control” emotions, inability to make and keep friends, stress, anger, thinking errors, and resistance to change.

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My Aspergers Child - Syndicated Content