It is a disorder that usually begins during the first 3 years of life, and parents are the first ones who begin to identify behaviors in their child that are different from those of other children their age. Some of these strange symptoms are: no or very little verbal communication, the child is very unsociable and solitary, or shows no interest in identifying objects or calling the parents' attention.
The distinguishing feature of this type of autism is that it occurs almost exclusively in girls and is regressive in nature. Affected individuals begin to suffer a progressive degenerative process of the nervous system that manifests itself in the form of alterations in communication, cognition and motor skills (both fine and gross) around the age of 2 years. These girls have a normal psychomotor development, at least in appearance, until then. However, several studies show that, even in the asymptomatic period, there is a reduction in muscle tone (hypotonia).
It is the most difficult and sometimes late type of autism to diagnose, because the affected persons do not have any intellectual disability or physical trait that identifies them. The deficit is in the field of social skills and behavior, being important enough to seriously compromise their development and social and occupational integration.
Problems with social interaction, lack of empathy, poor psychomotor coordination, not understanding irony or the double meaning of language, and obsession with certain topics, are some of the most common characteristics of Asperger's.
Childhood disintegrative disorder or Heller's syndrome
It usually appears around the age of 2, although sometimes it does not become evident until after the age of 10. It coincides with the other types of autism in affecting the same areas (language, social function and motor skills), but differs in its regressive and sudden character, to the point that sometimes the child himself becomes aware of the problem, showing his concern to the parents.
Pervasive developmental disorder not otherwise specified
It is a diagnostic label used in those cases in which the clinical symptoms are too heterogeneous to be included in any of the other types. Disorders of social reciprocity, severe communication problems and the existence of peculiar, restricted and stereotyped interests and activities are also present.