A problem of communication and interaction is what autism represents. Isolation is the most common experience that people with autism are living. Their problems may be described as mental retardation if we read the studies tell confirm that more than 8 out of 10 persons with autism have an IQ lower than 35. This thing is true but also true is the fact that the rest of the patients have higher scores at these tests, in many cases even above the average.

Autism is a problem that affects its patients from an early age. Children with autism have problems with using nonverbal behaviors such as eye to eye looks, facial expressions and even body postures. They are unable to make friends because of lack of social interactions or interest.

People with autism not only that they are not able to sustain a conversation but they do not show any interest in initiate one. While talking to somebody a person that suffers of autism uses repetitive language and gestures.

Repetitive behavior, interests and activities are also problems that occur in autism. For example we may say that persons with autism focus on things that are not really important for normal people, or we may say that they are having repetitive motor mannerisms or an odd preoccupation for parts of objects. These problems are seen in childhood autism.

Asperger's syndrome develops almost the same problems: qualitative impairments in social interaction such as problems in developing nonverbal behavior, or inability to build up per relationships and lack of interest for them and others. The same restricted, repetitive and stereotyped behavior is seen in these cases too. The insignificant delay in language is one of the differences between Asperger's syndrome and autism. Other differences between the two problems are the normal cognitive development in the Asperger's syndrome and also the curiosity about items but not for social relations shown in these situations unlike for people with autism.

Rett's disorder may also be considered an autistic disorder. In the first months the newborn is not showing that his development may be affected, contrarily he develops normally, but after 5 months he begins to lose previously acquired skills and may develop severe psychomotor retardation.

Childhood disintegrative disorder leads to loss of the expressive language developed until that moment, or the loss of the adaptive behavior that parents were used to. The loss of the motor skills also represents a risk if not a certitude.