In WS, certain anatomical features are underdeveloped or faulty. This includes certain facial features (you'll see them having unusually wide-eyed expressions), certain heart and artery muscles etc. More importantly, perhaps, specific parts of the brain are highly underdeveloped, while others are either overdeveloped or at least unusually dominate because the others parts aren't developed properly. The parts that are underdeveloped are the ones that have an important role in numerical/logical thinking and spatial sense. The parts that are often overdeveloped or seem to dominate are the ones that have roles in linguistic skills, social skills and apparently emotional impact of music (thats where "musicophilia" comes in).
So, people with WS are highly gregarious... extremely friendly and social with everyone.. they almost completely lack any social inhibitions, so that they seem to be completely comfortable in the presence of almost anyone, regardless of whether they are familiar with them. Moreover, they actually seem to enjoy such interactions and seem to be unusually clued-in to the emotional cues in other peoples behavior/facial expressions etc.
Their linguistic skills are almost always highly developed, making them highly articulate. This, along with their friendly/social nature means that you'll always find them having long, extended conversations with almost anyone. On the other hand, they find it extremely difficult to do even the most simple math problems. You could be talking on phone with someone who has WS and probably won't realize that anything is unusual (other than the person being unusually charming and friendly) until you ask him/her to tell you what 3+5 is. Chances are, they'll fumble through the problem and will probably only guess an answer, which will probably be wrong anyway. Lack of a normally developed spatial sense means that they find it hard to work with even simple geometric shapes (like the toys that toddlers play with) and can hardly draw even simple things like a triangle or a circle. In short, as Sacks says, they are almost anti-autistic in their characteristics.
Sacks talks about some people having WS that he has met. There are really interesting stories here. e.g. when one little girl's mom told her not to talk to strangers, she replied with "but there are no strangers, there are only friends"
Another girl he met (she was about 7-8 years of age) was so clued in to other people's facial features and was so completely uninhibited in front of strangers that she surprised him by sensing his slight diffidence and said promptly something like "don't be shy! I'll make some muffins for you". This, from a girl, who had never met Sacks before. Sacks had gone to her home to see her and was probably only about as inhibited as any of us would be when we go to someone's house for the first time (Well, some of us are probably more inhibited than others... my diffidence would probably be easy to sense for almost anyone. :P )
Anyway, so she went ahead and got some muffins for him. In some time, Sacks asked her (perhaps after covering the plate, though I am not sure) to guess how many muffins there were in the plate. She guessed, with some effort, "3". Then he asked her to go ahead and count them. She tried and counted them one by one and came up with 8. There were actually 13.
Another girl, a 15 year old, had an IQ of 49 - quite typical of people with WS. So, her average mental level was of around a 7-8 year old kid i.e. about a student of 2nd standard. But that doesn't mean, as I said before, that you'd be able to tell that by just talking to her. It's not as if they seem "retarted" in any sense. math/logic/spatial sense don't work properly, but they are exceptional in linguistics. They are highly articulate, which makes things difficult when they are in new company (difficult for them, sure, but also difficult for these new people). After all, none of us expect someone to be that articulate, YET having mental problems
Take this 15 year old girl with IQ 49. They asked her to tell them about what an elephant is. And her response, quoted below, is amazing in its detail. It is almost as if she is telling a story rather than answering a simple question :
"And what an elephant is, it is one of the animals. And what the elephant does, it lives in the jungle. It can also live in the zoo. And what it has, it has long gray ears, fan ears, ears that can blow in the wind. It has a long trunk that can pick up grass, or pick up hay… If they are in a bad mood it can be terrible…If the elephant gets mad it could stomp; it could charge. Sometimes elephants can charge. They have big long tusks. They can damage a car… It could be dangerous. When they're in a pinch, when they're in a bad mood it can be terrible. You don't want an elephant as a pet. You want a cat or a dog or a bird…"
So, to put it mildly, she knows something about what an elephant is. The amazing part is, after this, when they asked her to draw an elephant, this is what she drew -
copyright: Ursula Bellugi, the Salk Institute
(The labels were put by someone else to help others see what she might've been trying to make. She only made the figure.) Clearly, she knows about the fan like ears and tusks etc, but she can't draw any of those details at all.
The connection with music is pretty interesting actually.. all of them are strongly sensitive and emotionally attached to music. Now, this doesn't necessarily mean that all of them are very good at playing music or singing (though a lot of them are). This is, as Sacks points out, quite unlike musical savants. Musical savants are almost finished articles. They will dazzle the whole world by their exceptional musical talents, yet, they might not necessarily derive as much pleasure out of music as a normal person around them. WS patients, however, invariably feel very strongly towards music.
This strong emotional connection to music, in combination with their completely uninhibited nature means that you'll find them merrily singing or whistling or playing music or swaying to music a lot of times. if you are walking on the road and they suddenly hear you even humming something they'll just smile broadly and will likely start singing along with joy. Some parents/guardians of a lot of WS patients decided to get a lot of together for a camp. Sacks describes what he saw at one of these camps and it sounds amazing. 15-20 people with WS - most, but not all, very young - sit together and talk to each other as if everyone is part of a close family. Talk about everything under the sun. And then, suddenly, someone starts humming and everyone joins in.. Some play their instruments, while others jump in and harmonize. Some just let their bodies follow the rhythm. I'd say that it is pretty sad to know about this, but it's really difficult to feel that way after reading about their joy in these camps or, indeed, their connection to music.