One problem I see with this kind of study is that valproic acid has a very distinct effect (from personal experience), which makes it easier for participants to determine whether they are in the placebo group. It would be nice if there were an "active placebo" group who took another mood stabilized that is not an HDAC. Also, it would have been nice to see the effect on ability to produce a tone by humming or whistling, given the pitch name.

Some very weak anecdotal evidence in favor of the hypothesis: For a couple months in 2005 I was being treated with valporic acid and, during that time, I took an undergraduate course in topology. In my brief stint as a graduate student (2012), I also took topology and performed much better in this than in any of my other courses, though this could just be due to liking the subject.