Introduction
Autism is a neuropsychiatric disorder that once it occurs lasts all through a person’s lifetime. It is characterized by a major problem in communication and social interaction, as well as stereotyped and repetitive behaviors (Paul and Wetherby, 2005). This problem is a serious developmental disorder that affects the way a child sees and interacts with the rest of the world. It affects boys at least four times as often as girls. It limits their ability to interact with others socially and most of the time try to avoid human contact. In 1908, Eugen Bleuler a Swiss psychiatrist coined the word “autism” in schizophrenic patients who screened themselves off and were self-absorbed. Leo Kanner, while at Johns Hopkins, was first to describe autism in 1943 (Yazbak, 2003).
Leo Kanner described children with the following common traits: impairments in social interaction anguish for changes, good memory, belated echolalia, over sensitivity to certain stimuli (especially sound), food problems, limitations in spontaneous activity, good intellectual potential, often coming from talented families. He called the children autistic. Autism and psychosis continued to be confused for many years and researchers searched for the underlying cause of contact and language disorders, but they realized that the disability was more complex (Certec, 2004).
Epidemiological work in the late 1970s, by Lorna Wing and Judith Gould in the UK, established autism as a true syndrome, marked by a triad of reliably occurring together with impairments in socialization, communication, and imaginative or flexible behavior (Wing and Gould, 1979). Researchers searched for the primary cause of socialization and language disorders, but they were unable to find a single cause. In the 1980s autism research gained speed and researchers became convinced that the basic reasons were to be found in neurological disturbances, sometimes combined with hereditary illnesses like tuberous sclerosis, metabolic disturbances like PKU, or chromosomal aberrations such as fragile X-chromosome (Certec, 2004).
Symptoms
Autism is a developmental disorder defined by diagnostic criteria specified in DSM-IV (Diagnostic and Statistical Manual of Mental Disorders, American Psychiatric Association, 1994). Autism has been puzzling scientists for more than half a century. The complex behavioral disorder encompasses a wide variety of symptoms, most of which usually appear before a child is three years of age. Children with autism are unable to interpret the emotional states such as anger, sorrow, or manipulative intent of others. Their language skills are often limited, and they find it difficult to initiate or sustain conversations. They normally exhibit an intense preoccupation with a single subject, activity, or gesture. Intensive behavioral therapy improves the outcome for many patients, but their symptoms can make it impossible for them to live independently, even if they have normal IQs (Rodier, 2000). Individuals with autism show a broad range of difficulties and disabilities, and they vary greatly in their levels of overall intellectual functioning. However, all individuals diagnosed with autism possess a common set of symptoms. The National Autistic Society lists the following triad of impairments:
- Social interaction. This involves difficulty with social relationships, inappropriate social interactions, and inability to relate to others in a meaningful way, impaired capacity to understand others’ feelings or mental states.
- Social communication. Children with autism have difficulty with verbal and non-verbal communication.
- Imagination. For instance, a child with autism has difficulty in the development of play and imagination (Dautenhahn and Werry, 2004).
As of now, autism is more recognized as a genetic disorder with a profound impact on the development of the central nervous system. However, there is still no biological marker that is pathognomonic of autism. Research with modern neuroimaging techniques such as magnetic resonance imaging and positron emission tomography is aiding to map out the neural systems affected by autism. But there is a lot that needs to be done in this field to bring out substantial facts about autism. Even though autism involves hits to multiple systems, it remains possible that the initial insult is localized. The social, language and behavioral problems that occur with autism suggest that the syndrome has affected a functionally diverse and widely distributed set of neural systems. There is important evidence on this score from animal models of autism. These show that an initial insult to one system can propagate to affect other systems during the earliest months and years of development.
The genetic origin of autism is a well-accepted fact by researchers around the world. It is a familial disorder. Statistical modeling of twin and family data suggests that autism is one of the most strongly genetic of all neuropsychiatric disorders. The specific susceptibility genes have not yet been discovered. Autism is thought to be caused by a small number of genes acting in concert, rather than any single gene. Preliminary data from family linkage studies suggest that susceptibility genes for autism may lie on chromosome 7, with some other evidence also pointing to chromosome 15 (Schultz, 2001).
In recent years, there is also a postulation that mercuric content in vaccines might be a reason for autism. Some studies suggest that mercury could damage brains, kidneys, and developing fetuses. In recent years this issue has gained importance especially among the parents who have children affected by autism. It is being claimed that the mercury content used as a preservative in vaccines is responsible for the increase in the number of autism cases around the world. Though this claim still needs to be investigated, there is a need for evidence.
According to a CDC epidemiologist named Tom Verstraeten, who had analyzed the agency’s massive database containing the medical records of 100,000 children, a mercury-based preservative in the vaccines called thimerosal is considered to be responsible for a dramatic increase in autism and a host of other neurological disorders among children. Ever since 1991, when the CDC and the FDA had recommended that three additional vaccines laced with the preservative be given to extremely young infants especially the newborn the estimated number of cases of autism had amplified to fifteen fold. In numbers, it increased from one in every 2,500 children to one in 166 children (Kennedy, 2005). In conclusion, the cause of autism still remains unknown. It is important to encourage intense research in this direction.
References
Certec, (2004) The History of Autism. 2007. Web.
Dautenhahn, K. and Werry, I. (2004). Towards interactive robots in autism therapy Pragmatics & Cognition 12:1, 1–35.
Kennedy, R.F. Deadly Immunity, Published on Thursday, 2005, by Salon.com, Common Dreams NewsCenter, 2007. Web.
Paul, R. and Wetherby, A. (2005) New Autism Collaboration Develop Practices in Communication Assessment for SLPs ASHA Leader. Rockville: Vol. 10, Iss. 3; pg. 11-13.
Rodier, P.M. (2000). The Early Origins of Autism. Scientific American, Vol. 282 No. 2: 56-63.
Schultz, R.T. (2001). Autism, Neural Basis of. International Encyclopedia of the Social & Behavioral Sciences. Elsevier Science Ltd. 983-987.
Wing, L. and Gould, J. (1979). Severe impairments of social interaction and associated abnormalities in children: epidemiology and classification. Journal of Autism and Developmental Disorders 9, 11-29.
Yazbak, E.F. (2003) “Autism in the United States: a Perspective”. Journal of American Physicians and Surgeons, Vol. 8, No. 4, 103-107.