Ok, so I was browsing through the lessons a little bit ago and I clicked on a lesson for playing arpeggios. One of the exercises includes something like this repeated a few times:

My question is how are the notes in parentheses supposed to be played? I've always had a bit of difficulty understanding them.
Here's the link if you want to see the rest and get the whole picture.
They are ghost notes. You still play them, but muted. Not just like a normal palm mute, but completley muted.
Ah. I guess I just didn't make the connection between that part and the tab. Thanks a bunch.