Autism spectrum disorders (ASD) are a set of developmental disorders, with symptoms that are usually chronic and can range from mild to severe. 1 in 100 children may appear to have some type of autism spectrum disorder, although recent research conducted in the United States states that ASD has a prevalence of 68%.
In general, ASD is characterized by the alteration of the individual’s ability to communicate and establish social relationships.. It is a complex disorder that affects the development of the individual who suffers from it and is generally diagnosed around the age of 3 years.
There are different types of autism spectrum disorder. Now, this classification has undergone some modification with the publication of the Statistical Diagnostic Manual of Mental Disorders (DSM-V). Below we will review the different subtypes of ASD and the changes reflected in the DSM-V in its latest editions.
Changes in the DSM-V regarding autism spectrum disorder (ASD)
In its fifth edition, the DSM, published by the American Psychiatric Associationhas incorporated changes with respect to ASD, since it has eliminated diagnostic criteria used for decades. In fact, over the years, ASD has been subject to various modifications in this manual. In its first edition (1952), it was classified with the term “childhood schizophrenia”, which is far from the current concept. Each of these changes has created some controversy, and the new edition of the DSM has been no exception..
One of the most notable modifications with respect to the DSM-IV refers to the symptomatology of ASD. If in the fourth edition the diagnostic definition of autism spectrum disorder was characterized by three symptoms known as the triad: deficiencies in social reciprocity, deficiencies in language or communication, and a restricted and repetitive repertoire of interests and activities. In the fifth edition there are only two categories of symptoms: deficiencies in social communication (that is, it includes the first two previous categories although it presents some changes with respect to them) and restricted and repetitive behaviors.
Furthermore, if in the DSM-IV autism belonged to “pervasive developmental disorders” (PDD). In the DSM-V, this definition has been replaced by “autism spectrum disorders” (ASD), which is included under “neurodevelopmental disorders.”
On the other hand, the subcategories of this disorder have also undergone modifications. The fourth edition included five subtypes of autism: autistic disorder, Asperger syndrome, childhood disintegrative disorder, pervasive developmental disorder not otherwise specified (PDD not otherwise specified), and Rett syndrome. In the fifth edition, Rett Syndrome has been dispensed with, leaving only 4 subtypes.
Types of Autism Spectrum Disorder disorders
But, What characteristics do types of autism present? In the following lines we explain it to you in detail, although it must be taken into account that all the phenomena described by these differentiated categories, in practice, overlap a lot and share characteristics.
1. Autism or Kanner Syndrome
This is the disorder that most individuals associate with autism spectrum disorder.and is named after Kanner Syndrome in relation to Dr. Kranner, a doctor who studied and described this condition in the 1930s.
Subjects with autism They have a limited emotional connection with othersand it seems that they are immersed in their own world. They are more likely to display repetitive behaviors, for example, they may arrange and rearrange the same group of objects, back and forth for extended periods of time. And they are highly sensitive individuals to external stimuli such as sounds.
That is, they may become stressed or agitated when exposed to specific noises, bright lights or sounds or, on the other hand, they will insist on wearing certain items of clothing or colors or they will want to be located in certain areas of the room without any problem. apparent reason.
Asperger Syndrome is an autism spectrum disorder that is more complicated to diagnose. and, sometimes, this diagnosis is usually made later than the previous case. This occurs because these subjects with Asperger’s have a medium (high) intelligence that can cause the difficulties and limitations that these subjects present to be undervalued.
The deficit is, therefore, in the field of social skills and behavior, being important enough to seriously compromise their development and social and work integration. In addition, people with Asperger Syndrome show deficiencies in empathy, poor psychomotor coordination, do not understand irony or the double meaning of language and become obsessed with certain topics.
The cause of Asperger’s Syndrome appears to be the dysfunction of several brain circuits.and the affected areas are the amygdala, the frontostriatal and temporal circuits and the cerebellum, areas of the brain that are involved in the development of social relationships.
Although the media has helped spread an image of Asperger’s syndrome in which this condition is described as a mental disorder associated with high intelligence, it should be noted that the majority of people grouped in this category do not score significantly above the normal IQ, and a very small number of them obtain very high scores.
3. Childhood disintegrative disorder or Heller syndrome
This disorder, usually referred to as Heller Syndrome, usually appears around the age of 2 years.although it may not be diagnosed until after 10 years.
It is similar to the previous ASD because it affects the same areas (language, social function and motor skills), although It differs from these in its regressive and sudden naturewhich can cause even the subject himself to realize the problem. Individuals with Heller Syndrome can have normal development up to the age of 2, and after this time suffer the characteristic symptoms of this disorder. Different studies conclude that this disorder is between 10 and 60 times less common than autism. However, his prognosis is worse.
4. Pervasive developmental disorder not otherwise specified
When the clinical symptoms presented by the subject with autism spectrum disorder are too heterogeneous and do not fully fit the previous three types, the diagnostic label “pervasive developmental disorder not otherwise specified” is used.
The subject with this disorder is characterized by having a deficit of social reciprocity, severe communication problems and the existence of peculiar, restricted and stereotyped interests and activities.
It should be noted that if the rest of the types of autism are already diverse in themselves, in this last category it is even more important to take into account the unique characteristics of each individual, and not fall into the trap of letting the label completely explain the person. This classification system is only an aid that allows us to rely on a series of concepts to better understand this condition, but it does not exhaust all the possible explanations about what each person is experiencing or what they need.
Difficulties when studying autism
Something to keep in mind about the different types of autism is that It is very difficult to study them without falling into biases.
For example, it is problematic to investigate the communication patterns of autistic people using their ability to interpret the emotions expressed in the expression of the eyes, given that they tend not to focus on that part of the face.
Thus, the inability to interpret these expressions does not exactly mean that they do not know how to interpret the emotions of others, but rather that they do not know how to do it in that specific way, but perhaps using other ways to do so.
In turn, the errors made by not taking into account these variables that contaminate the studies can lead to the creation of artificial distinctions between types of autism where only personality variables, motivation when following instructions, etc. are really working. .
