When I'm on the receiving end of an Fe user's increasingly loudness, it feels just as Orobas described it: It's sort of like the Fe user doesn't feel validated by my silence, or they think I missed the point and they get increasingly more and more blunt with me until they just boil over with anger toward me. (Whew that is always stressful when that happens. And I'm often completely surprised by the eruption coming my way.)
When the dynamic is reversed and I, an Fi user, is getting louder with an Fe user... well, it doesn't feel like I'm getting increasingly blunt. More like I'm getting increasingly "truthy." In other words, I ramp up my Fi truthiness activity to the point where I'm calling it like I see it, consequences be damned. (And, I can tell it's stressful to the Fe user, but it's like I can't stop what I'm doing.)
So I guess I agree with Cadesco that increasing loudness isn't necessarily related to cognitive functions. But it seems to me that the way increasing loudness manifests and the way it is received, IS related to cognitive function. As the stress increases, our cognitive functions sort of "run home to momma" and revert to just doing what they each do best... in this case of getting louder, Fe makes increasingly blunt statements about the situation as they see it, and Fi gets more truthy and authentic as it defines truth and authenticity.
For the person on the receiving end of the "loudness" there have to be differences, too. I'm not so sure I fully understand these. It seems like Fe users are far more likely to avoid confrontation via the avoid, the ignore, and the doorslam. I think Fi users are more likely to want to hash it out and clear the air. (I could be talking from my Te perspective here, but it feels right to me.)
Anyone have any thoughts on this? Does it ring true to you?