Autismo

Critically evaluate the evidence for a biological basis of autism spectrum disorders.

Introduction
The aim of this essay is to critically evaluate the evidence for a biological basis of autism spectrum disorders.
Autism spectrum disorders (ASD) are a group of developmental disorders affecting social interaction of a child, the communication skills and behaviours and interests. Autismspectrum disorders may also be called pervasive developmental disorders (PDD). Autism spectrum disorder symptoms include mild to severe disabilities. Depending on their severity, have been identified in all five syndromes, including autism, pervasive developmental disorder not otherwise specified and Asperger syndrome, as well as rare conditions such as Rett's disorder and childhood disintegrativedisorder. Autism spectrum disorders affect about one in every 175 children. Researchers are not sure what the exact cause of these disorders.
Autistic disorder and Asperger's disorder, which are included in the category of pervasive developmental disorders, are usually evident in the first years of life. Children with these disorders have difficulties to realize basic development tasks that relateto language, communication, socialization and motor behaviour. These disorders are rare and seem to have a genetic cause. Treatment may include a combination of medication and specialized training to develop and improve the acquisition of necessary skills.
Lorna Wing, 1979 [online] Available at: http://www.uv.es/bellochc/logopedia/NRTLogo8.wiki?9 “used the term Autism Spectrum Disorder,considering what is known as "Wing triad": a disorder of social reciprocity, communication disorder and verbal and non-verbal symbolic capacity and lack of imaginative behaviour”.

Main Body
In 1943 Leo Kanner published "Autistic Disturbances of Affective Contact," “his ground-breaking article defining a new condition which he called autism. In 1944, unaware of Kanner's work, Hans Asperger published"Autistic Psychopathy in Childhood" ("Die 'Autistichen Psychopathen' im Kindesalter"), describing a very similar condition and also giving it the name autism”.
Knowledge of Autism is advancing rapidly, but we are still far from a clear answer to their nature and specific causes. It is a neurodevelopmental disorder caused by prenatal Central Nervous System dysfunction. The disorder syndromes arecharacterized by a triad of symptoms observed in the first 3 years of life;
• Qualitative impairments in reciprocal social interaction
• Qualitative impairments in communication and restrictive forms,
• Repetitive and stereotyped behaviour, interests and activity in general.
Currently, there are three levels of analysis and scientific explanation of autism spectrum disorders which areobservable behaviours and symptoms, mechanisms, processes and psychological functions, and systems and neurobiological mechanisms.
A behavioural analysis
The symptoms that characterize autism clinically are highly variable. The most severely affected (which also suffer mental retardation) lack of social and communicative initiative, behave very rigid and stereotyped, lack of symbolic play and showgreat inflexibility to changes in the environment.
People with higher levels of cognitive functioning (without associated mental retardation) a interested in the relationship with other people, they can develop considerable skills or abilities such as music, drawing or computer, but the interaction is strange; the verbal and nonverbal communication are often inconsistent showing little reciprocityin relationship. They tend to talk only about issues of the interest and, are rigid and inflexible in their habits of behaviour and opinions.
Neurobiological Analysis
It is seen as a prenatal neurodevelopmental dysfunction affecting distorting and psychological brain ontogeny.
There are brain areas involved, the diversity of ideas backed by researchers are extensive although, no definitive...