brain structure changes with any learning, unless one presupposes dualism
I am not sure that is the case. My neuroscience is very rusty, but is there a distinction between structural changes and other changes? New neural connections versus changes in neurotransmitters or triggering thresholds seems a likely candidate.
General Intro:
http://www.bbc.co.uk/news/health-16086233
Older research:
http://www.fil.ion.ucl.ac.uk/Maguire/Maguire2006.pdf
Abstract of latest research
Possible implications for WBE (Is it possible to get short term function correct without having the ability to do long term structural changes?)
Also possible implications for learning lots of information, cabbies with "the Knowledge" had worse visual information recall.
I haven't gone through it all myself yet.