As far as I understand, neuropsychology gains most of its insights from the reconciliation of lesions of the brain and **cognitive impairments**. Normal functioning (both of the brain and the mind) plays a less important role in neuropsychology.

My question is: 

> Which role does **cognitive high-performance** play in
> neuropsychology? Which attempts are there to map cognitive high-performance processes to neurophysiological structures and processes?

Examples of cognitive high-performance:

 - [eidetic memory][1] (e.g. [Stephen Wiltshire][1])
 - memorization of pi (e.g. [Akira Haraguchi][2])
 - [mental calculators][3] (e.g. [Gert Mittring][4])
 - advanced mathematics
 - advanced chess playing

The mere fact that for such high-performers there are possibly enlarged (and internally more strongly connected) areas of the brain (and connections between them) is not what I am looking for. Especially for the more mathematical and intricate cases there must be more than that.

The main difference between *neuropsycholgy by impairment* and *neuropsychology by high-performance* seems to be that in the former case you can more easily perform statistical studies (but also single-case studies), in the latter case you can only perform single-case studies.