Autism and Autism Spectrum Disorder are terms used to refer to complex disorders that impair brain development. In 2013, the DSM-5diagnostic manual grouped all autism related disorders under the ASD diagnosis. Prior to this, the autism disorders were classified as different subtypes including Asperger syndrome, pervasive developmental disorder-not otherwise specified, autistic disorder, and childhood disintegrative disorder.
Research shows that autism may have its roots in the early stages of brain development. However, most parents will discover the signs of autism when their children reach the age of 2 or 3 years old. Technological advances have availed screening methods to parents who might think their child is exhibiting signs of autism. The screening methods can determine whether the patient is at risk of developing autism as early as one year old.
Commonality of Autism
The US Centers for Disease Control and Prevention estimates that about 1 in every 68 children in America are on the autism spectrum. The estimation is a 10% increase in the prevalence of autism within the last forty years. Research indicates that this increase could partially be attributed to increased awareness about the disease and improvements in diagnosis.
Furthermore, current research indicates that autism is five times more common in boys than in girls. The CDC data indicates that 1 out of 42 boys in the United States will present signs of autism while only one out 189 girls will present with the same symptoms. Children with elder siblings with ASD are 10 times more likely to develop signs and symptoms of autism. The report also suggests that ASD affects more than 3 million Americans and tens of millions more across the globe (GBDSC, 2015). Globally, autism affects approximately 21.7 million people. By 2010, 1or 2 individuals per 1000 across the globe was believed to be affected by the cognitive development disorder.
ASD has also been described as the fastest-growing cognitive developmental disorders in the United States. However, the fast growth of the disorder is probably due to early diagnoses in children. Children are now being screened and diagnosed with autism as early as 18 months. There is still debate on whether actual rates of autism have increased over the years.
Signs of Autism in Toddlers
The signs and symptoms of autism usually appear within the first three years of a child’s life. Others will show autistic symptoms from birth while others will grow normally and then seem to slip suddenly when they are 36 months old. It is now a widely recognized fact that some people do not show symptoms until the demands of their immediate environment overwhelms their capabilities.
It is critical for parents to recognize the early signs of autism in their children and seek immediate intervention methods. Intervening early enough will ensure improved outcomes for the child. Early intervention can improve social skills, verbal and non-verbal communication, as well as learning as the child grows.
Some of the signs of autism in toddlers include loss of speech, and babbling, lack of babbling by 12 months, lack of warm and joyful expressions by six months, lack of back and forth gestures including pointing or reaching by 12 months, lack of meaningful two or three word phrases by 24 months, and lack of babbling by 12 months.
The main characteristics of autism include difficulties in different types of communication, social interactions, and exhibiting repetitive behaviors. Children who exhibit several recurring behaviors such as spinning their toys at their first birthday are four times more likely to be diagnosed with autism than children who do not demonstrate any repetitive behaviors (Netting, 2014).
Other defining characteristics of ASD include short attention span, gastrointestinal and sleep disturbances, intellectual disability, and pervasive difficulty in motor coordination. Most children with autism have varying degrees of difficulty in communicating with others. As a result, they often find it difficult to understand others’ feelings, thoughts, and actions. Furthermore, they also find it extremely difficult for such individuals to express themselves clearly verbally or through non-verbal communication.
Autistic children often display signs of obsessive-compulsive disorder (Griswold, 2015). Such connections have led scientists to believe that OCD and ASD share similar genetic roots. Compared with normal people, individuals with autism are twice more likely to be diagnosed with OCD. Similarly, people diagnosed with OCD are four times more likely to be diagnosed with autism.
Research also shows that when a member of a family has OCD, autism is more likely to run in the family as well. According to Griswold (2015), when one parent has OCD, there is a higher chance of their children being diagnosed with autism. The high numbers of autism diagnoses among children whose parents have OCD clearly point to the two conditions sharing a genetic predisposition.
Causes of Autism
Several causes of autism have been proposed but the exact cause has never been identified. What is evidently clear is that the structure and the shape of the brain in autistic children are very different from that of non-autistic children. The heritability of the disease is very complex and determining which genes are responsible has proven elusive to the scientists. Many scientists are suspicious that a single cause of autism does not exist. Rather, the evidence points to the disease being a complex disorder with certain definitive aspects that have a variety of causes.
Extensive research on the causation of autism has hinted that genetic factors may predominate the causative agents for autism. Studies of child twins estimate that the heritability of the disease was between 60%-90%. For adult siblings, the risk of one of them having autistic features might be as high as 30%.
Despite the strong heritability, several cases of ASD occur sporadically without any prior evidence of the disease in the family. Some researchers concluded that spontaneous mutations in the mother’s egg or father’s sperm could result in the development of autism (Freitag, 2007). Evidence to support this theory includes the fact that autistic individuals are less likely to have children than the rest of the population. Their reduced fecundity curtails the continuance of the mutations in the autism genes over several generations. Furthermore, children born to older fathers will are more likely to develop autism as mutations in sperm accumulate, as a man grows older.
Epigenetic mechanisms may also increase the risk of an individual developing autism. Epigenetic alterations occur because of the modification of chromosomes or DNA bases. They do not occur because of sequence changes in the DNA (Freitag, 2007). Mental stress, drugs, and nutrition are known to be causative agents of changes in the epigenetic mechanisms of the brain and body.
The prenatal environment is also considered to increase the risk of individuals being diagnosed with autism. The prenatal risk factors include bleeding, diabetes, use of psychiatric drugs, and advanced age during pregnancy. Studies show that birth defect factors working during the first weeks of conception can significantly increase the chances of the baby developing autism.
Infectious processes during pregnancy are considered the most prevalent non-genetic causative agents of autism in children. Prenatal exposure to viruses such as cytomegalovirus will send the mother’s immune system into overdrive, greatly increasing the risk for the infant to develop autism. Infections during early pregnancy have a bigger impact on neural development than infections during late pregnancy for several psychiatric diseases apart from autism.
Diabetes in the pregnant mother may increase the risk of the development of autism in the embryo. Research showed that pregnant women with gestational diabetes were twice as likely to give birth to children with autism. Despite the figures produced from such studies, the biological connection between the risk of autism and gestational diabetes has not yet been discovered.
Misconceptions about the Causes of Autism
There was a time when people believed that autism was caused by vaccines, specifically the MMR vaccine. This was after Andrew Wakefield and his co-researchers carried out a study on 12 children with bowel problems and autism. Wakefield suggested that the symptoms of both conditions began after the administration of the MMR vaccine (Wakefield, Murch, Anthony, 1998). The Centers for Disease Control and Prevention among other institutions carried out their own investigations and found the earlier study to be flawed and fraudulent. The research was consequently retracted from a number of medical publications including The Lancet.
There was a point when the public erroneously believed that autism developed in children who had refrigerator mothers. Bruno Bettelheim, a child psychologist, who linked childhood trauma to the development of autism, developed the theory of refrigerator mothers as autism causative agents. Refrigerator mothers refer to emotionally distant mothers who withheld affection from their children (Farrugia, 2009). Such women were held responsible for the development of autism in their children. Bettelheim’s emphasis on his hypothesis and the treatments he prescribed did not seem to help autistic children. After his death, it was discovered that he had fraudulently reported his cure rates of autism. Consequently, the theory was denounced and considered baseless.
The thimerosal vaccine was also once considered a cause of autism in children. The thimerosal controversy claims that the vaccines containing the preservative thimerosal can significantly increase the chances of children developing neurological disorders including but not limited to autism. Thimerosal is a mercury based preservative and many people believed that the mercury contributed to brain development issues in children.
As a result, the preservative was phased out of all children vaccines in the European Union and in the United States (Baker, 2008). Exposure to mercury can result in damage to a developing fetus as well to brain, and kidney damage. However, there has not been any conclusive scientific evidence to suggest that thimerosal had such effects on brain development in children.
Autistic Children Can Excel
Despite all the cognitive and physical difficulties, many ASD patients excel in different fields including art, visual skills, math, and music. New research indicates that children with ASD have greater academic and artistic abilities than had previously been imagined. There is a discrepancy between their IQ scores and their performance on tests especially spelling, math, and reading tests. Research shows that 90% of high-functioning autistic children perform extremely well in IQ tests demonstrating that they have a high intelligence despite poor performance in other tests. Thus, more and more autistic children are being placed in the high-functioning range.
Academic achievement for children with autism is a source of self-pride. It also brings about the feeling of mastery that was previously unable to children with ASD (Roseth, 2010). Scientists believe that the improved academic achievement of these kids is because of early childhood behavioral interventions and improved diagnosis of the disease. Now, nearly 70% of children with autism are now considered to be in the high functioning range. However, their autism makes it difficult for them to engage successfully in social communication.
Early interventions that minimize problem behaviors and improve the child’s social skills can increase the chances of autistic children learning in regular classrooms. Scientists have also discovered a strong link between academic ability and social skills. Autistic children with higher social skills by age six demonstrated better math solving and word reading skills by the time they turned nine. Thus, early intervention is critical in ensuring that these children lead normal lives.
Further research into the cognitive ability of autistic children demonstrates that such individuals were more likely to come up with unique answers to creative problems. This is despite the fact that most of these individuals have difficulties in finding jobs and have traits that make them socially awkward (McVeigh, 2015).
Baker, J.P. (2008). Mercury, Vaccines, and Autism: One Controversy, Three Histories. Am J Public Health 98(2):244-253.
Farrugia, D. (2009). Exploring stigma: medical knowledge and the stigmatization of parents of children diagnosed with autism spectrum disorder. Sociology of Health & Illness, 31 (7): 1011-1027.
Freitag, C.M. (2007). The genetics of autistic disorders and its clinical relevance: a review of the literature. Mol Psychiatry 12(1): 2-22.
Global Burden of Disease Study 2013 Collaborators-GBDSC (2015). Global, regional, and national incidence, prevalence, and years lived with disability for 301 acute and chronic diseases and injuries in 188 countries, 1990-2013: A systematic analysis for the Global Burden of Disease Study 2013.
Griswold, A. (2015, Dec 3). Sweeping study underscores autism’s overlap with obsessions. Spectrum. Retrieved on 26/4/2016 from https://spectrumnews.org/news/sweeping-study-underscores-autisms-overlap-with-obsessions/
McVeigh, T. (2015, Aug 22). People with autism and learning disabilities excel in creative thinking, study shows. TheGuardian. Retrieved on 26/4/2016 from http://www.theguardian.com/society/2015/aug/22/autism-creative-thinking-study
Netting, J. (2014, Mar 20). Repetitive behavior in toddlers may signal autism. Spectrum. Retrieved on 26/4/2016 from https://spectrumnews.org/news/repetitive-behavior-in-toddlers-may-signal-autism/
Roseth, B. (2010, Nov 22). Many Autistic Children Can Excel. Futurity. Retrieved on 26/4/2016 from http://www.futurity.org/many-autistic-children-can-excel/
Wakefield, A., Murch, S., & Anthony, A. (1998). Ileal-lymphoid nodular hyperplasia, non-specific colitis, and pervasive developmental disorder in children. Lancet, 351 (9103): 637-641.