Research on autism shows that autism is a pervasive developmental disorder that manifests itself as unsuitability for the social and family environment and an inability to communicate with others.
According to the WHO International Classification of Diseases, autism is a pervasive developmental disorder that affects brain function. It is no longer considered a psychological condition or a psychiatric illness.
Different terminologies are used: Autism, Autistic Disorder, Autism Spectrum, ASD (Autism Spectrum Disorders), PDD (Pervasive Developmental Disorders)…
Autism is a disease that affects the functioning of the brain, the immune system and biological, alters the recognition capabilities of expressions, social and emotional codes, generates emotional hypersensitivity and behavioral disorders.
It is a severe and early developmental disorder of the child of neurobiological origin, appearing before the age of 3 years. It is characterized by isolation, disruption of social interactions, language disorders, non-verbal communication and stereotyped activities with restricted interests. The manifestations of autism may vary from one child to another and in the same child over time.
Three cumulative elements characterize autism: a communication disorder, a disruption of social relations and behavioral disorders.
Today we talk more about ASD than autism. Other ASDs include Fragile X Asperger Syndrome, Landau-Kleffner Syndrome, Rett Syndrome, Childhood Disintegrative Disorder, and NOS-PDD (Non-Specified Pervasive Developmental Disorders). Recent research on autism shows that many people with autistic behavior have related but distinct disorders.
ASD cannot be cured. For many children, symptoms improve with treatment and age. Growing up, some children with autism eventually lead a normal or near-normal life. Therapies and behavioral interventions can target specific symptoms and make significant improvements. In contrast to twenty years ago, when many autistic people were institutionalized, there are now more flexible solutions. In general, only the most seriously affected individuals live in institutions.
Research on Autism Shows on Three Forms of Early Autism
* Very early form: first months
* Form starting between one and two years
* Form that occurs after the age of two years
I – Characteristics
Autism is essentially characterized by deficient social interaction. Parents are usually the first to detect the symptoms of autism in their child. Already in the infant stage, a baby with autism may not respond to others or may focus very carefully on one area of interest to the exclusion of others for very long periods of time.
An autistic child may seem to develop normally and then become withdrawn and become indifferent to any social contact. Many children with autism display reduced sensitivity to pain, but are unusually sensitive to sensations such as sound, touch, or other sensory stimulation. These unusual sensitivities can result in behavioral symptoms such as resistance to being cuddled or hugged.
II – Screening
Screening for autism in children is essential for management.
*** Different Forms of Autism
Difficult to recognize the first signs of autism. Because there is not one but several diseases, according to the gravity (the Asperger’s syndrome is the least handicapping form). Whatever the attack, we can distinguish three types of problems:
Communication Disorders. The language is confusing. Often, the autistic echoes what he hears. In addition, the codes of nonverbal communication (gestures, look …) are poorly understood.
Behavioral Disorders. The autistic repeats the same movements regularly. He constantly practices the same activity with the same objects and lacks interest in other hobbies.
Disturbances of social relations. Autistic does not participate in group activities spontaneously. He is indifferent to others.
*** Recognize the First Signs Autism
The first signs of autism manifest themselves slowly, subtly in the first year of life. It takes a set of symptoms to be able to make the diagnosis. If screening tools exist, health professionals are not very aware of the signs of autism, so the diagnosis is often made very late, often after three years. While ideally these disorders should be detected before 18 months.
III – Symptoms
The first signs of autism appear before the age of 3 years. In 70% of cases, children are mentally retarded with an Intellectual Quotient (IQ) below 70. In addition, 30% of them are prone to epilepsy.
Children with autism find it difficult to acquire the use of speech, which sometimes appears “disorganized”, that is, it does not fit into a coherent verbal exchange. One observes, for example, the repetition of words or phrases heard and repeated like an echo. Autistic people reproduce repetitive behaviors with their bodies like shaking hands, pendulum movements, and mania. They adopt routine habits and are reluctant to changes that disrupt their world.
Autistic people often have anxiety attacks, sleep disorders or eating disorders. They may be angry and have aggressive attitudes, including towards themselves.
The child refuses any contact with the outside world. The child is as in his bubble, indifferent to the outside world. The people around him have trouble getting in touch with him. He does not look in the eyes. Any attempt “intrusion” leads to a crisis, so it is called “empty fortress”.
IV – Causes of Autism
The causes of autism are not yet fully understood. In the 1950s, a current of psychoanalysis felt that bad relationships between parents and their children could be responsible. This theory, which made parents feel guilty, is no longer valid and is replaced by a bundle of genetic, biochemical, immunological and traumatic explanations. The international scientific community and WHO describe autism as a disorder of brain development during its maturation period.
*** Genetic Factors
Family-based studies have identified a genetic risk factor. The probability that a second autistic child is born in an already affected family is 3%, which is about 60 times higher than in the general population.
Many genes have been identified whose alteration seems to lead to greater susceptibility to autism. These genes are involved in various biological processes, but many of them participate in the formation of the nervous system and synthesis of chemicals essential for the proper functioning of the brain, such as serotonin, glutamate, acetylcholine or GABA.
*** Environmental Factors
* Valproic acid, an antiepileptic drug, taken in pregnant women appears to promote the occurrence of autism (or related disorders) in children.
* Selective serotonin reuptake inhibitors (SSRIs) taken during pregnancy.
* Perinatal respiratory disorders.
* Exposure to air pollution during pregnancy.
* The fact that the mother suffered abuse during her childhood.
* Premature births, cesarean births, and newborns that are too light are more likely.
* Nutritional deficiencies of the mother, especially in vitamin and folic acid.
* The links between a high testosterone concentration during fetal life and the appearance of autistic traits are the subject of various studies.
V – Diagnosis
The diagnosis of autism and other pervasive developmental disorders (PDD) is clinical and is based on a dual approach:
* An in-depth interview with the parents, in order to better specify the various stages of the child’s development and to draw up an assessment of his current behaviors and interactions.
* The observation of the child and interactive scenarios, in order to evaluate the different manifestations of the autistic syndrome that he may present, and the degree of his ability to form social bonds, communicate and interact with a child. given environment.
Autism often goes unnoticed in early childhood, it is generally with the entry into society (nursery, school, daycare) that the demonstrations are flagrant, by the difficulties of social interaction, problems of verbal and nonverbal communication, and repetitive behaviors or narrow or even obsessive interests. These behaviors have repercussions that go from the benign stage to the handicapping stage.
VI – Treatment
There is no cure for autism. Studies have shown that only 10% of people reached an independent social life.
However, the earlier the diagnosis is made, the more the support allows to develop the communication skills with others.
Every child with autism is so different from the other that care must be individualized. It is essential to take care of these children as soon as possible. Because the younger the child, the more malleable his brain is. And the more he is able to develop functions that can compensate for deficits due to autism. Language learning, the acquisition of non-verbal communication tools, the development of social skills, these are the main skills to aim for. The main objective is to promote, as far as possible, the social integration of the child. The establishment of a reassuring environment around the child and the awakening of the senses of the latter are other essential pillars of autism treatments.
VII – Some Discoveries and Research on Autism
1 – Discovery of New Genes
Autism Genome Project. Started in 2002, the Autism Genome Project brings together 177 scientists from more than 60 institutions from 11 different countries to form the largest consortium on the genetics of autism. This project was born from the desire of researchers from around the world to come together to share their samples, data, and expertise to facilitate the identification of genes involved in autism.
This group of researchers has discovered genetic mutations and new genes involved in autism. These works were published in the journal Nature in June 2010.
The international research group analyzed the entire genome of 1000 people with autism-related disorders and 1300 control individuals using high-resolution microchips. Scientists have been able to highlight insertions and deletions of genetic sequences, invisible under the microscope. These reworkings, called “variations in the number of copies,” made it possible to identify new genes involved in autism. Some of them act at the level of contacts between neurons (synapses), while others are involved in cell proliferation or intracellular signaling.
These findings support an emerging consensus within the scientific community that autism is caused in part by many rare variations or genetic changes detected in some affected individuals.
2 – Autism Is Due to an Excess of Synapses in the Brain
According to a team of neuroscientists at the Columbia University Medical Center, whose work appeared in the journal Neuron in August 2014, autism is thought to be due to an overabundance of synapses in the brain.
Synapses are the junction points through which neurons communicate with each other. They are the ones that allow the transfer of information into the brain. In autistics, it is an excess of information circulating in the brain that would be at the origin of typical symptoms such as hypersensitivity for example.
During its development, the brain of newborns – autistic or not – sets up a very important network of synapses. The brains of babies are hyper-connected. But as the child – then the adolescent – grows up, this excess of synapses gradually disappears due to a natural mechanism of pruning. Over time, many synapses become useless and are eliminated by the brain.
In autistics, this mechanism of pruning synapses is stopped. It is the hyperactivity of the mTOR protein that is involved. It would inhibit this natural mechanism of pruning.
The research on autism discovered this glut of synapses by analyzing brain tissue, the seat of neurological function, of 48 young people aged 2 to 20 at the time of death. 26 had autism and 22 were normal. Neuroscientists have calculated that, on average, a 19-year-old without autism had 41% fewer synapses than a youth with autism.
New therapeutic strategies could be considered based on this discovery. The researchers managed to suppress the symptoms in genetically modified mice to simulate autism. Using rapamycin, they restored the mechanism of pruning synapses. The drug administered to the mice in the study would act by inhibiting the activity of mTOR, which would thus return to a normal pruning of synaptic connections.
3 – Mother’s Antibodies – Risk Markers in Autistic Children
Experts at the Davis Mind Institute of the University of California, in a study published in Translational Psychiatry in July 2013, identified a new risk factor for autism in a group of children. These are the antigens of these maternal antibodies that target brain proteins and prevent the fetal brain from developing normally. Originally present in the mother’s blood, these antibodies play a role in the etiology of a form of autism, called by researchers “autism MAR” for “Maternal Autoantibody-Related”.
The research on autism shows that mothers of autistic children are 21 times more likely to have these specific antibodies that react with these antigens.
These maternal antibodies pass through the placenta during pregnancy and must be detected in a fetus as early as 13 weeks of age. By 30 weeks, the maternal antibody levels in the fetus are about 50% of those of the mother, and at birth, their concentration is higher in the newborn than in the mother. The maternal antibodies remain in the baby’s bloodstream for 6 months after birth, and then the baby’s immune system takes over. Once in the fetal blood the antibodies enter the brain and attack the brain cells some of whose proteins act as antigens. This antigen-antibody response is directed against the organism itself, as in an autoimmune disease.
The development of a diagnostic test may be made available to mothers of young children who show signs of developmental delay. If the test is positive, the early behavioral intervention will be considered. Administration of antibody blockers to the mother during pregnancy may help protect the developing fetal brain.
This important discovery not only provides a biomarker for the early diagnosis of this form of autism but also a target for drug development.
4 – The Prenatal Vitamin B9 or Folic Acid Reduces the Risk of Autism
According to a study by researchers at the Davis Mind Institute of the University of California, published in the online edition of the scientific journal Epidemiology in May 2011, women who would not take vitamin B9 early in their pregnancy would twice as likely to have children with autism. The research on autism also points out that folic acid supplementation has the potential to prevent up to 70% of neural tube defects.
Women who reported not taking a prenatal vitamin daily immediately before and during the first month of pregnancy are at double risk of having a child with an autism spectrum disorder, but this risk is up to seven times higher when it is associated with a genetically more sensitive risk.
The authors add that folic acid, the synthetic form of folate or vitamin B9, and other B vitamins in prenatal supplements are likely to protect against deficits in the early development of the fetal brain.
5 – Exposure to High Levels of Testosterone Increases the Risk of Autism
According to researchers at the University of Cambridge, whose study is published in the journal Molecular Psychiatry in January 2010, exposure to high levels of testosterone in the uterus increases a baby’s chances of developing autism.
Autism affects boys more often than girls (3 or 4 for a girl). A “masculinization” of the brain, linked to an action of testosterone and the Y chromosome would be involved. These different actions would inhibit the potential of communication (visual exchanges and speech). This would result in confinement in his world of autism. According to the research on autism, the harmful action of the hormones could be triggered from the fetal stage – when they are secreted by the mother – or later during the development of the child.
They found that for 128 boys who were going to develop autism later, the levels of steroid hormones in the amniotic fluid that had bathed them as a baby in the womb were, on average, particularly high.
In comparison, much lower levels of the steroid hormone were detected in the corresponding amniotic fluid of a control group of 217 boys, who did not have autism.
The results may explain why autism is more common in men, these hormones are produced in greater numbers in boys than girls, say researchers.
Testosterone and three other steroid hormones – are important for the development of the fetus, which means that it would be too risky to block them.
6 – Abnormal Development of the Cerebral Cortex During Pregnancy
Autism is one of the three disorders recognized under the generic term of the Spectrum of Autism and is a neurodevelopmental disorder. People with autism show a damaged social and communication interaction and often display certain characteristic behaviors. Although there has been some information about the brains of autistic people, when and how autism develops was little known. New evidence indicates that autism develops very early in pregnancy. And these offer the hope of a screening “at the source” of autism and therefore that of effective treatment.
Researchers at the University of California at San Diego in a study published in the New England Journal of Medicine in March 2014, explain that a disruption of brain architecture has been detected in brain samples of autistic children.
Autism thus results from abnormalities in the development of certain brain structures of the fetus. A discovery that could help detect this syndrome much earlier.
The more we advance in research on autism, the findings suggest that autism begins during pregnancy – or autism begins in the uterus during pregnancy.
7 – A Process That Occurs Long Before Birth
This reflects a process that occurs long before birth. Currently, autism can be detected from two years old. But it is known that earlier detection would lead to much more effective therapeutic strategies.
Physicians analyzed post-mortem brain specimens from 11 autistic children aged 2 to 15 at the time of death. They compared them to samples from a control group of 11 other children who were not autistic.
The development of a fetus’s brain during pregnancy involves the creation of a cortex – or cerebral bark – made up of six distinct layers of neurons. The researchers found, in places only, abnormalities in the development of these cortical layers in the majority of children with autism.
The analysis of a series of 25 genes that serve as biomarkers for certain types of brain cells forming the six different layers of the cortex revealed that these bio-markers were absent in 91% of the brains of children with autism compared to 9 % in the control group.
During early brain development, each cortical layer develops its own specific cell types, each with specific patterns of connectivity that play unique and important roles in the processing of information.
By developing into a specific type, cells acquire a distinct genetic signature (marker) that can be observed. In the brains of autistic children, key genetic markers were absent in cells of multiple layers. This indicates that the early stage of development of these distinct layers, which begins in prenatal life, has been disrupted.
These defects are not present uniformly but are presented “in patches”. The most affected regions are the frontal and temporal cortex.
The frontal cortex is associated with so-called higher level cognitive functions, which include communication and the complex understanding of social cues.
The temporal cortex is associated with language. The visual cortex, associated with perceptions, presented no anomaly.
Two types of cells are present in the cortex. Nerve cells (neurons) were affected but not glial cells.
These abnormalities present in unequal ways, as opposed to uniform cortical pathology, may help explain why many autistic infants show improvement with early treatment and over time, the researchers say.
The signs of disorganization of the brain cells appeared as spots 5 to 7 millimeters long at various locations in the different layers of the frontal and temporal lobes of the brain. These brain regions are the seat of social functions, emotions, communication and language, which are dysfunctional in autistic people. The mechanism responsible for this disorganization of the cortical structures is a dysfunction of the gene networks that control the production of brain cells and the formation of the six different layers of the cortex.
According to the researcher, this discovery has the potential not only to identify when and where these abnormalities develop but also their cause, perhaps opening the way for a much earlier detection of autism.
In addition, the fact that these abnormalities are sparse and do not affect all layers of the cortex should allow the brain to reconstruct these defective connections using healthy cortical tissue.
These results support the idea that in children with autism, the brain can sometimes develop new connections to circumvent abnormalities, which gives hope that understanding these abnormalities may open new avenues to better understand how these improvements occur.