If you really understand the difference between top-down and bottom-up learning and thinking, you can begin to understand much of what is happening with people with autism. And the more bottom-up the learning and thinking, the slower learning is going to take place.
Those who are top-down learners and thinkers typically only have to experience something once or twice before they “have it.” For example, a top-down thinker only has to experience a social situation once or twice for that social experience to be generalizable to other, similar social situations. However, bottom-up learners have to have many more such experiences before they can become generalizable. Thus, oftentimes, a social situation is experienced as being completely new, even if it is similar to other social situations experienced in the past.
Let us say that we have a bottom-up thinker for whom 10 similar social experiences are needed before those experiences can be generalized into similar experiences so that the 11th experience is familiar enough for the person to have a proper response to that experience. If it is a common experience, such as a daily school routine, those ten experiences will accumulate fairly quickly, and the person in question will soon know how to properly respond to that situation. If this person is fortunate enough to have someone around who can point out that certain social situations are in fact similar, he might even be able to learn more quickly (since bottom-up thinkers are also more explicit learners). But if the social situation is a rarer one, the bottom-up thinker might not learn how to negotiate such situations for a decade or more. And, of course, if some situation is spaced out enough, it might take more than the typical ten times for the patterns to become apparent.
Worse, imagine this same person is working at a job, and he has the social experience of someone failing to do their job in a timely manner, which is required for him to do his job. The top-down thinker will maybe get burned by this situation once or twice before they learn the proper thing to do in such a situation. The bottom-up thinker will, given the one we have posited here, get burned ten times before he learned the right thing to do. What are the odds he will have gotten fired before then?
Many top-down thinkers will have learned most social rules by their early twenties. However, bottom-up thinkers may take years or decades more to learn those same rules. The former will thus be more likely to keep their jobs for long periods of time; if not the first job or two, certainly the second or third. The latter, however, will be faced with the same situations in more and more jobs, and fail to understand they are really facing the same situation each time. Thus you can end up with someone in their forties not understanding a social situation that they “should have” learned by the time they were twenty. How stable will that person’s work history be? Not very.
The most extreme bottom-up thinkers are those on the autism spectrum. The more bottom-up a thinker is, the more severe that person’s autism will be (or vice versa). All learning will be slower, but social learning will be particularly slow, because social situations cannot typically be repeated as often as can facts. Learning language is going to be equally slow, because words have to be associated with concrete reality, and words have to be repeated in their proper context, for the autistic person to learn those words. Learning words is, after all, a negotiation between the empirical world and mental abstractions. More, grammatical structures being learned more explicitly than implicitly is going to slow down language learning for those who are bottom-up language learners. This style of learning — bottom-up, explicit learning — is what makes social learning so slow and difficult for people with autism. Without accommodations for that, people with autism are going to continue to have problems in life and work.