The concealment often extends to the characteristic symptoms of Asperger syndrome. A person with TFAS rarely has a special interest but, if anything, they have a lack of interests in the world. Although they may express an interest in football, their interest is not the passionate one of the fan or of the amateur player. It is more as if the person with TFAS knows that some interest is expected of them. In fact a person with this form of Asperger syndrome may spend long periods in inactivity.
Repetitive activity is concealed, too.
Parents may report that their son or daughter with TFAS has stereotyped activities which become very intrusive at home, but are usually concealed when the person is with a stranger. Repetitive questioning may be one, but others may be rocking, smoothing the hair, repeating words, or vocalizations. Sometimes these stereotypes are quite similar to those of people who have Tourette syndrome but they are not confined to sniffing or swearing. As in some people with Tourette syndrome and indeed some young people with obsessional disorder, people with TFAS are more likely than other people with AS to fly into a rage. This explosive anger is frightening can lead to hitting or breaking things.