zHi, Jack. To get back to the study that you linked, the heart of the study was this:

Researchers...identified 38 healthy individuals aged between 18 and 63 and tested their propensity to hallucinate, musical aptitude and measured their detailed brain structure using an MRI scanner.

The researchers observed that participants with higher musical aptitude showed lower hallucination proneness. More importantly, the research revealed musical aptitude was positively associated with corpus callosum integrity whereas hallucination proneness was associated with lower integrity in the fibres connecting the two hemispheres of the brain.
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I have my doubts about this study.

1) If people are healthy, they don't have hallucinations.

2) How does one measure "proneness to hallucinations"?
3) 38 is a small number of subjects.
4) What if I have high musical aptitude but never had a chance to
   play an instrument?

It makes sense, however, that activities which strenghthen the corpus callosum make for a better-functioning brain. I wish them well.