Central coherence is the ability to build wholes out of parts. It is weak in people with autism. This means that autistic people focus more on details. They cannot build wholes out of them. Not being able to pay attention to wholes results in difficulties with perception and language. Therefore, people with autism usually need more time for dealing with information coming from their surroundings. As a consequence, they typically also need more time for responding. However, performance varies between people on the autism spectrum. Moreover, the term central coherence may include many interacting aspects. This makes it difficult to find the cause for it in the brain. Neural correlates for central coherence are not yet known.
The risk for autism spectrum disorders can be increased if the mother uses thalidomide, valproic acid or drinks too much alcohol during pregnancy. The risk for autism also increases with the age of father and mother at the time of pregnancy.
Scientists know that parents do not cause their children's autism by not being loving enough.
Scientists do know for sure that vaccines do not cause autism. Vaccines do not even make a person more likely to have autism - even if they are already at a high risk for autism before they get their vaccines.
In 1997 A. Wakefield and others found autism signs one month after the measles-mumps-rubella (MMR) vaccine was applied. They released a paper in which they claimed that autism is caused by the MMR vaccine. However, the study had several flaws:
Also, no plausible biological mechanism could explain how the MMR vaccine leads to autism. Since then many case-control studies have been done to investigate the relationship between vaccines and autism. This means, they compared a group which was vaccinated with a group that was not vaccinated but apart from that identical. They did not find MMR vaccines to be the cause of autism. Neither did they find an increased risk for autism by the vaccination.
Parents also worried that thiomersal (US: thimerosal - a substance that makes vaccines and other medicines usable for a longer time) might cause autism because it contains mercury. No harm from the amount of ethylmercury in vaccines was known. Yet, vaccines for infants containing mercury were taken from the market. Nevertheless, thiomersal as a cause for autism is biologically also not biologically. Mercury poisoning triggers clearly different symptoms than autism. Still, researchers did studies about this topic. They did not find a connection between thiomersal and autism.
Finally, a third theory was suggested. It was stated that many vaccines at the same time would weaken the immune system of infants. However, autism is not a disorder that is related to the immune system. Furthermore, single and also many vaccines do not weaken the immune system.
Diagnosing autism is difficult since there is no medical test like a blood test. Instead, an evaluation is made by a team of doctors and other health professionals who are experienced in autism and know the individual.
A reliable diagnosis can first be given at the age of two. At the age of 18 and 24 months, children should get a check-up. If anything wrong is noticed, a further evaluation is done. In this, a team of professionals will interview the child’s guardians about the child’s behaviour and see what they are like in different settings. This may also include behavioural or physical assessments as well as intelligence tests or developmental tests. A good, detailed, history of the child is often very useful in receiving a diagnosis.
Adults can be diagnosed in adults as well as children. This can be difficult because autism has symptoms that can overlap with other disorders, such as OCD, that may have appeared by adulthood. An expert will usually ask the adult about concerns, challenges in life (such as socially or behaviourally) as well as standardised testing in these areas. They also often ask for a developmental history.
In 2013, the American Psychiatric Association published the fifth edition of the Diagnostic and Statistical Manual of Mental Disorders (DSM-V). In order to be diagnosed with autism, a person must fulfill two standardized criteria. It is important that individuals must show symptoms from early childhood, even if those symptoms are recognized later. These symptoms have to limit everyday functioning. Additionally, these symptoms cannot be explained by an intellectual disability or a developmental delay.
Autism Spectrum Disorder is characterized by difficulties in social interaction, verbal and nonverbal communication and repetitive behaviours.
Autism spectrum disorder includes a wide range of symptoms, skills and levels of disability. Some autistic people also have learning disabilities, mental health issues or other conditions. This means that autism can also co-occur with other conditions and symptoms of the following disorders:
In the DSM-V, a diagnosis of autism excludes making a formal diagnosis of other psychiatric disorders. Therefore, other mental health conditions may be undiagnosed in an autistic person, because it is impossible to make a comorbid clinical diagnosis.
Since autism is a spectrum, every person with autism is different. Different treatments help different people. There are a few different categories of treatment. The main ones are medication, different therapies and diets. The treatment is fitted depending on what a person with autism needs.
It is still unclear what causes autism. There may be a few causes. At the moment, it is only possible to lower the symptoms of autism. A full recovery from autism is not possible. If therapies cannot reduce the symptoms of autism, medications are used additionally. Often, several medications are used at the same time to treat different symptoms of autism.
Serotonin is a chemical messenger that transports signals between cells and is very important for normal function, such as with sensory perception, memory, learning and sleep, all of which are impaired in autistic people.
Researchers have not yet found a link between autism and serotonin, although they have been successful in treating autism with SSRIs, which stop cells from absorbing serotonin, meaning more is used for signals.
They can be used to treat repetitive behaviour, aggression, hyperactive behaviour and outbursts of anger. The SSRIs can have many side-effects. Usually the medication is better tolerated by adults than by children. Examples of SSRIs are Clomipramine, Fluvoxamine, Sertraline, Venlafaxine, Trazodone and Mirtazapine.
Dopamine is a chemical messenger in the brain. It helps to do movements, release hormones and strengthen cognitive abilities. Researchers found that increasing the amount of dopamine in the brain will worsen the symptoms of autism. Substances that help to reduce symptoms of autism are the antipsychotic drugs. There are two types of antipsychotic medications. One of the types are typical antipsychotics. They block the sites where dopamine would bind to a cell. Atypical antipsychotic drugs on the other hand block the sites where dopamine or serotonin would bind to a cell. Antipsychotic medicine is the most successful treatment for excitability in autism. It can also help to reduce aggression, self-injury, hyperactivity and repetitive, although it may have many side-effects. Originally, antipsychotic medications were used to treat mental disorders like depression, bipolar disorder or schizophrenia. Examples of antipsychotic drugs are Haloperidol, Clozapine, Risperidone and Paliperidone.
In the beginning, psychostimulants were only used for patients with Attention Deficit Hyperactivity Disorder. Researchers found out that they can also help patients with autism. The medication can reduce hyperactivity and inattention in people with autism. The medication can have many side-effects. Examples are Methylphenidate, Clonidine and Guanfacine.