In your review you cite cross-sectional research, not a longitudinal, within-subject effect of change with study/practice/learning. Therefore your conclusions should not be about change, but on group differences. Those difference might have arisen from the training, or pre-existed in those individuals that were more prone to study/practice/learn/meditate.
Post-Note: Sorry. As a developmental neuroscientist, you hit on a pet-peeve. Cheers.
Personally, I do think the brain is plastic in this sense though. I haven't looked deep enough into it to be a 100% certain. Nevertheless, from all the research summaries I read, I gather that whenever a skill is practiced in a focused manner for 1 to 2 hours, neural plasticity occurs.
I wish there was a literature review around this idea. But I got the feeling that 4 years ago the literature was mostly on clinical patients. Normal people and neural plasticity seems to be researched less well.