You walk down a street and nearly bump into someone; you look at their face and in a fraction of a second you know who it is. It does not really matter if you see them in profile or full face. And one can do this with thousands of faces; a clever trick of our brains. How do we recognise faces?
The probability of having autism is greater for an individual if it runs in their family. This suggests hereditary factors. But what do you actually inherit? What you inherit is a predisposition for a specific development of your brain. This, together with what you experience while growing up, can lead to the development of a mild to severe form of autism.
What is the relation between what the neurologist calls amazing and the psychiatrist paradoxical? Our impression of the world around us is not formed on the basis of what we actually perceive with our senses. Instead, we carry a preexisting image of our surroundings in our head, and we check if that matches with our perceptions. Sometimes this goes awry.