As I understand it, the one key feature of autism spectrum disorders that helps to set them apart from other neurodevelopment issues like SPD w/o ASD is the child's reaction to or ability to engage in social interactions.
A gifted child (especially one from a language rich environment) may have very high functioning language that masks this underlying deficit/difficulty. This is true with our son.
Depending on the age of your child this can be hard to figure out. But here are some possible examples or ideas of observations that may help you sort this out:
Does the child avoid direct eye contact or break off direct eye contact very quickly? This can be very subtle, especially in a child who is in "constant" motion. Repeated observation with peers and people from outside the family may be the most useful since he may have built up some tolerance for eye contact with close family members. It often seems as though there's a good "reason" for the shift in eye contact so regular observation over time and with different people may be necessary to identify this pattern.
Can the child take the perspective of the reader when writing (for older children)? This is a major issue for my son and is why his writing is often disorganized and incoherent. He is almost completely unable to take the reader's perspective.
Can the child engage in meaningful conversation with or "interview" another person about themselves? The essential skill here is the ability to generate a meaningful series of personal questions about another person's interests or activities that takes the other person's responses into account as the conversation progresses.
Many very high-functioning ASD children can engage in what I call pseudo-conversation but when you closely observe the content of their conversation you realize that they are not really asking these kinds of questions. They may ask about things in the other person's life (what kind of car you own, is that ball yours) but not about the other person's connection to or feelings about those things (why do you like that kind of car? Can we play with the ball together?).
Also they often turn the conversation very quickly to topics of interest to themselves or into a story about themselves that doesn't really have much emotional content or have much to do with the other person's conversational responses. For example, when asked to notice what was different about a series of photos of his speech therapist, my son pointed out that her hair was different in each photo. When prodded, he managed to ask the SP if she got her hair cut often. When she said that she did he immediately responded with a lengthy story about getting his own hair cut and failed to follow up with any meaningful questions for the SP about her own reasons for changing her hairstyle. Even when re-directed he could not come up with any questions for her. He is 13 1/2 and really should be able to do this at least a little. At the start of this assessment, when the SP asked him to interview her (after modeling this skill for him) my son flatly stated "I can't do that" and became clearly uncomfortable. He was right - he can't do that.
Problems with peers can include developing complex rules for games - a very "gifted" sort of thing to do. But in the ASD child, the rules will be arbitrary and inflexible and often focused on ensuring that the ASD child wins. The ASD child has little ability to recognize that other children want to win too, that the rules they have created are self-serving, and that peers don't want to play when there is no chance of winning. The gifted child's rules will make sense in terms of making the game more interesting or hard but not in a way that offers no chance of winning if you are playing with them - provided you are can follow their logic and remember all the rules
Difficulty with abstract thinking/concepts can be hard to identify in younger children but is also a fairly prominent feature of ASD's than may be helpful in distinguishing between gifted ASD and gifted non-ASD children.
In the child with apparently excellent language skills, you may find that the ASD child knows lots of words but doesn't necessarily know the meaning of the words he's using. His usage may be just a little "off" and adults tend to just correct the child's usage rather than ask the child "what does that word mean?". I suspect this is a very mild form of something found in more severe PDD's where the child parrots back something like a jingle from a commercial, over and over. The gifted ASD child hears a new word and retains it but may not understand the meaning, especially the abstract or emotional/social meaning of the word. He uses it in conversation, "parroting" the way he heard it used because that's the only way he knows to use the word.
It can be hard to differentiate these things and you may need to go to someone who specializes in ASD diagnosis with your questions.
Patricia
