True about autism –
Autism 

Autism is a neurologic disroder characterized by -


Qualitative impairment in social interaction
Qualitative impairment in communication.
Restricted repetitive and streotyped patterns of behaviour, interests, and activities.


Onset of symptoms is usually before 3 years of age.
3-5 times more common in boys, but more severe when occurs in girls.
More common among low socio-economic groups.

Clinical features

Impairment in communication
Impairment in social interaction
Inability to concentrate
Restricted repetitive and streotypes patterns of behaviour, interests and activities.
Failure to acquire speech.
Approximately 75% of children with autism are mentally retarded.
Epilepsy develops in approximately one-fifth to one-third individuals.
Half of autistic patients have abnormalties on EEG.
Occurs in high economic striata
Normal communication
Starts before 2–3 years of age
More common in girls