Childhood autism is a subtype of pervasive developmental disorder, prevalent in males, that begins in infancy and early childhood and manifests mainly with varying degrees of speech and language developmental disorders, interpersonal difficulties, narrow interests and stereotyped behavior. About 3/4 of patients have significant mental retardation, and some children have good ability in a certain area against a background of general intellectual backwardness. So, what are the symptoms of autism in children? The following are the symptoms of autism in children: 1. Social interaction disorder Patients cannot establish normal interpersonal relationships with others. At a young age, they show no eye contact with others, have poor expressions, lack expressions or gestures expecting hugs and caresses from parents and others, and do not have pleasant expressions when enjoying caresses, and even refuse hugs and caresses from parents and others. They do not distinguish between close and distant relationships and treat their relatives the same way as they treat others. For example, they are often alone in kindergarten and do not like to play with their peers; when they see some children playing games together, they do not have the interest to watch or the desire to participate. 2. Intellectual impairment Among autistic children, the level of intellectual performance is very inconsistent, with a few patients in the normal range and most patients showing varying degrees of intellectual impairment. According to domestic and international studies, about 50% of autistic children have moderate intelligence deficiency (IQ less than 50), 25% have mild intelligence deficiency (IQ 50-69), 25% have normal intelligence (IQ more than 70), and those with normal intelligence are called high-functioning autistic children. Language disorders Language and communication disorders are important symptoms of autism and are the main reason for most children to be seen. Language and communication disorders can take many forms. Most children with autism have delayed or impaired language development, usually remaining non-verbal at the ages of two and three, or regressing in language after normal language development, having expressive language until the age of two to three, gradually decreasing with age or even losing it completely, being silent for life or using limited language in rare cases. They have some degree of impairment in both their ability to perceive and use language expressively. 4. Narrow range of interests and stereotyped behavior patterns Patients are not interested in the games and toys that normal children are passionate about, but prefer to play with non-toy objects, such as a bottle cap or observing a spinning fan, and can continue for tens of minutes or even hours without boredom. The patient is not interested in the main features of the toy, but is very concerned with the non-main features: the patient stubbornly demands that the routine remain the same, e.g., the time of going to bed, the quilt covered, and the same route to take when going out. If these activities are stopped or the behavior pattern is changed, the patient expresses significant unpleasantness and anxiety, and even defiant behavior. Patients may have repetitive stereotyped actions, such as repeatedly clapping their hands, spinning in circles, licking the walls with their tongue, and stamping their feet.