Social Impairments

Although there is no single feature that all people with Asperger syndrome share, difficulties with social behavior are nearly universal and are perhaps the most important criteria that define the condition. People with Asperger syndrome lack the natural ability to see the subtexts of social interaction and also lack the ability to broadcast their own emotional state.

Non-autistic's are able to gather a whole host of information about other people's cognitive and emotional states based on clues gleaned from the environment and the other person's facial expression and body language, but people with Asperger syndrome have an impairment in this ability, sometimes called mind-blindness. To be mind-blind is to find it difficult or even impossible to figure out things a person implies but does not say directly (more colloquially, to "read between the lines"). This is not because they cannot imagine the answer but because they cannot choose between the possibilities; the mind-blind person cannot reliably gather enough information to do so or does not know how to interpret the information he or she does gather.

Along with this difficulty in reading the nonverbal communication of others, most people with Asperger's have difficulty expressing their own emotional state via body language, facial expression, and nuance as most people do. Such people have emotional responses as strong as, or perhaps stronger than, those of most people, although what generates an emotional response might not always be the same; the difficulty is in expressing these feelings, although it sometimes comes across as lacking them. For example, many people with Asperger syndrome have difficulty with eye contact. Some make very little eye contact because they find it overwhelming, whereas others have un modulated, staring eye contact that can cause discomfort to other people. Similarly, the use of gestures may be almost nonexistent or may seem exaggerated and differ from what would normally be considered appropriate for a situation.

It is worth noting that because it is classified as a spectrum disorder, some people with Asperger syndrome are nearly normal in their ability to read and use facial expressions and other subtle forms of communication. However, this ability does not come naturally to most people with Asperger syndrome. Such people must learn social skills intellectually, delaying social development.