I found a “scientific” article – number skills, using how you counted on your fingers as a child. Apparently, where you were born has a lot to do with how you use your fingers, and this in turn could affect your cognitive processes. Obviously, the article is more of my favorite “why we are who we are” and “why we do what we do”. 
Leadership and management
Excerpt: The finger-counting technique you learned as a child may influence how good your grey matter is at crunching numbers
Finger counting techniques vary widely between cultures and could affect cognitive processes.
Read full article via What does the way you count on your fingers say about your brain? | Corrinne Burns | Science | guardian.co.uk.
