This is an interesting article:
For starters, guitarists literally have the ability to synchronize their brains while playing. In a 2012 study in Berlin, researchers had 12 pairs of guitarists play the same piece of music while having their brains scanned. They discovered that the guitarists’ neural networks would synchronize not only during the piece, but even slightly before playing. So, basically, guitarists can read each others’ minds better than they can read music.
That synch happens in the areas of the brain that deal with music production and social cognition, so it makes a real difference in how tight a band sounds. When people talk about a band’s chemistry, this may well be what they’re seeing. It also explains why brothers are the core duo in so many famous rock bands.
Wow, seems Guitarists have brains ;-). Next they will say Drummers have brains too…….