Have you followed Dr. Amen's research. Very interesting approach to the diagnosis and treatment for all manner of brain functions. See his gallery of brain scans- SPECT on the amenclinic site.
One of his 'warnings' to young women is- avoid Soccer, women's intellingence is concentrated in the frontal lobe, exactly where the head butting occurs.
Check out two of his web sites: www.amenclinics.com www.dr-amen.com