For me it really depends. I have two ways of representing my speech.
1) experience the words as if I'm saying them out loud but don't vocalize them. This is similar to how a lot of people read, so I figure I'm technically subvocalizing them.
2) especially when doing math or programming I simply know what I was about to think using method 1) without any specific words springing up.
I can't figure out if method 1 is me having an auditory internal monologue or if it's non-auditory. But at least you have a second experience to contextualize with.
EDIT: I would also like to add that sometimes when programming my mind switches to a graph-like representation that I start to manipulate physically. That is, I'll actually move my fingers in the air and move around the idea of this graph to "view" it from different perspectives and at different levels "Minority Report"-stye. Yes, that is something I try not to do anywhere but at home.
You just made me realize that internal speech is, I think, a better way to understand the internal monolog (at least in my case) than internal hearing. I guess I can hear my internal monolog, but it's more about 'saying' the words in my head than 'hearing' them.
1) experience the words as if I'm saying them out loud but don't vocalize them. This is similar to how a lot of people read, so I figure I'm technically subvocalizing them.
2) especially when doing math or programming I simply know what I was about to think using method 1) without any specific words springing up.
I can't figure out if method 1 is me having an auditory internal monologue or if it's non-auditory. But at least you have a second experience to contextualize with.
EDIT: I would also like to add that sometimes when programming my mind switches to a graph-like representation that I start to manipulate physically. That is, I'll actually move my fingers in the air and move around the idea of this graph to "view" it from different perspectives and at different levels "Minority Report"-stye. Yes, that is something I try not to do anywhere but at home.