Aggression and Autism

A common complaint of teachers and parents regarding children with autism spectrum disorders is that his aggression came out of nowhere, unexpectedly like a storm, and
for no apparent reason. Aggression is more common among boys than girls, but can happen with both. It occurs more commonly among people with limited cognitive ability and who lack spoken language. Most of the time children and youth with an ASD are aggressive there is a pattern, but it may be difficult to discover. Effective behavior management strategies require understanding health conditions contributing to outburst, situations that trigger aggression and the functions aggression serves ,i.e. the consequences.


A setting event is something that happens earlier in the day or even the night before, that makes a behavioral outburst more likely. After a night of little sleep, the slightest request or demand by a parent or teacher may trigger aggression. For other children, a flare up of gastroesophageal reflux may set the stage for aggression. Other problems, like an earache, toothache, a bad cold, or constipation are setting events that make aggression likely. As with other children, youngsters with autism can have food allergies. The most common childhood food allergens are eggs, milk, and peanuts. Other less common food allergies include wheat, soy, and tree nuts. Children with food allergies usually experience intestinal cramps, gas and diarrhea. Though many parents believe their children with ASDs have gastrointestinal problems, a study conducted in England evaluated indications of chronic inflammation of the gastrointestinal tract, coeliac disease, food intolerance, and recurrent gastrointestinal symptoms recorded by doctors treating children under the National Health Service. Nine percent of children with a diagnosis of autism and 9% of children without autism had a history of gastrointestinal disorders, suggesting GI problems are roughly equally common. Most of health problems children with ASDs experience are “invisible” and parents often don’t think of them as events that lay the foundation for seemingly “random” aggression, which isn’t really random. Often treating the underlying health condition will reduce aggression.


Things that happen immediately prior to an aggressive outburst, like a parental request to “Put on your shoes”, may be followed by aggression. They are called Triggers. Half to two-thirds of aggressive outbursts are a way of avoiding an activity or situation that is too difficult or unpleasant to the child. To identify triggers, one must keep track of what happened immediately prior to aggressive outbursts, usually for at least a week. At first it may appear there is no pattern. On one occasion the child was eating his breakfast and had an outburst. On another he was watching TV and hit is brother. On another he bit another child in the classroom while playing on a swing. But if we look more closely we discover in each case someone told him to stop what he was doing, and to do something different (e.g. stop eating breakfast and get ready for school, stop watching a preferred TV program, stop swinging so the other child could swing).

Sometimes adult requests may seem too difficult for the child. He may lack the skills to do a task, such as “put on your shoes”, and aggression is a way of avoiding the task. Teaching prerequisite skills or making the task easier (e.g. by using shoes with Velcro strips) may eliminate the problem. Teaching the child to request “help” verbally or with a picture icon can avert many outbursts. Another alternative involves teaching the child to request to do a task later, using either a verbal or icon card to request a delay. That gives the child the feeling they have some control in a situation that they otherwise find impossible.

Sometimes aggression is triggered by requests to enter a place that is frightening to the child, like a crowded shopping mall, a room full of strangers or a doctor’s office. An outburst may occur well before the actual event if the child anticipates it is going to happen, which makes it difficult to connect the outburst with what she or he fears. Alerting the child to the forthcoming activity 3-5 minutes prior to the actual event, combined with explaining s/he will receive a treat as soon as they enter the mall, or leave the doctor’s office may help. Some parents who identify specific situations that cause problems go on practice runs to those locations when there are few other people present (e.g. Tuesday morning at 10am to the shopping mall) to desensitize the child so they will be less fearful. ,

Aggressive outbursts may be triggered by a change in routine that may seem inconsequential to adults but represents an intolerable change to the child. If a child’s usual teacher is out due to illness and a substitute teacher appears, or speech therapy is after lunch rather than before lunch as usual, or if where the child sits at the table during mealtime is changed, that can trigger an outburst. A child with an ASD should always be alerted to any forthcoming change, such as “Miss Jones is going to work with you after lunch today instead of before lunch”, pointing to a picture on the child’s Visual Schedule. Saying, “Miss Jones will have a treat for you when you finish your lesson”, often helps.


Many teachers and parents think that if they explain to a child who has just had an aggressive outburst why they must do a non-preferred task even if they don’t want to do it, that it will somehow help. It almost never helps and usually makes matters worse, because while the adult is “explaining”, the child is receiving undivided attention, which reinforces the behavioral outburst. Other adults believe scolding will help. It rarely helps and for the same reasons may make things worse. For younger children who have engaged in physical aggression, requiring the child sit in a specific chair in the corner of the room facing away from others (a form of time out) for 3 minutes can help. But it will only help if the situation from which they have been removed have lots of opportunities for rewarding activities. It gives the child time to calm down, and secondly, it assures no positive consequence occurs as a result of aggression. After the child has been quiet for 3 minutes, they should be returned to the same activity, but it should be made much easier so they almost immediately succeed.

Depending on cognitive level, it may be useful to contract with the child so they have an incentive not to have aggressive outbursts. For example, if the child successfully makes it through the morning at school without an outburst, they might be given 10 minutes to engage in a highly preferred activity before lunch.

Physical punishment methods, such as Positive Practice, Over Correction or other punitive methods usually backfire. In addition to providing the child with attention while being carried out, they create a coercive relationship between the adult(s) and youth. With older children and youth, ferreting out the Setting Events and Triggers is usually necessary to solve the problem.


Some types of seizures can involve physical assault. They are difficult to detect because the person may appear conscious, they may engage in what appear to be purposeful movements, but are actually not conscious and not aware of what they are doing. Temporal Lobe Epilepsy is fairly common among individuals with autism. It can only be diagnosed through using an Electroencephalogram conducted by a neurologist. Some doctors prefer to conduct the EEG after the child has been deprived of sleep, which makes it EEG abnormalities more obvious. Other doctors have the child wear a recording device connected to electrodes that track EEG abnormalities as they go about their daily routines. This is called an Ambulatory EEG. Whichever approach is used, if the young person with ASD has Temporal Lobe Epilepsy, there are several anti-epileptic medicines that often control the brain seizure activity as well as behavioral outbursts. While epilepsy is common in autism, it is seldom that behavior outbursts, such as aggression, is caused by undetected epilepsy.


There is evidence some individuals with ASDs have differences in the same brain structures as psychiatric patients with Obsessive Compulsive Disorder (OCD). People with autism often respond favorably to the same medications as those used to treat psychiatric patients with OCD. Children or adolescents who have numerous fixed routines, are highly intolerant of changes in routines, and who engage in repetitive, anxious speech (e.g. asking the same question repeatedly, or reciting television ads verbatim, over and over), may be candidates for treatment with Selective Serotonin Reuptake Inhibitor medications, such as Prozac, Luvox, Paxil, Celexa or similar medicines. There is evidence higher functioning individuals may be especially responsive to these medicines.


Older aggressive children and adolescents who are lower functioning cognitively, with little or no language, and who have not been responsive to a functional assessment based behavioral intervention strategy are often treated with atypical antipsychotic medications, such as Risperdal or Zyprexa. These medications have broad effects on brain chemical systems, and have been shown to reduce aggression, self injury and irritability (esp. Risperdal). This class of drugs often cause sedation, and very occasionally cause a movement disorder (dyskinesia).
With the exception of Abilify, nearly all atypical antipsychotic drugs cause weight gain and pose a risk for developing Type II Diabetes. Atypical antipsychotics may be an important form of treatment in order to gain control over serious aggression, but because of the weight gain side effect, are often only used for 3-6 months.

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