Monotropism
Monotropism is a way that the autistic brain works, and can be thought to be a big part of what defines autism. A monotropic mind is one that focuses very strongly on only a few things. Dinah Murray and Wenn Lawson made the theory of monotropism, which was written about in the journal Autism with Mike Lesser in 2005.
Monotropic minds can focus on things very strongly, but this means that it's likely for a monotropic mind to have 'tunnel vision', which is when things that are not being focused on are not noticed at all. This stronger thinking can be a very positive feeling. However, monotropism means that moving from one task to another is harder. Starting and stopping activities is also hard, because a monotropic mind keeps getting pulled to focus on a small number of things.