If you define all brain processing as "thinking" then for sure you're correct. I am not defining it that way, and I'm not aware that it's common to do so.
Visual images, for a start, are to me, quite different from thoughts. For a start, someone sitting next to me can share the same visual experience. They won't share the same thoughts. I can look at this monitor, or pretty much anything else, without any thoughts present. Thinking is not the same as seeing. Thinking is not the same as smelling. Thinking is not the same as emoting. It is, I would grant you, possibly related to hearing.
Nick
A-HA!
I think I understand a little better. You think in words, don't you, Nick?
Not everyone does. Some people think in spoken words - like you. Some think in written words. Some think in pictures. I think in icons.
Do you know the load screens on The Sims 2, with all those little generic images of chairs, shirts, etc.? That's very similar to how my thoughts work, except that there are also icons for actions, adjectives, abstract concepts, words, sounds, colors, etc. It's actually been a difficult road to get to where I am today, language-wise, because my first instinct is to communicate via icon. Obviously, there aren't many of us out there, or language might be a very different issue.
For you, hearing is related to thinking because you consciously think in words. For me, thinking is related to ALL SENSES, because every sensory input has a corresponding mental icon, and there is always a brief lag between sensation and comprehension for me, during which raw sensation is translated into comprehensible thought.
But, realistically speaking, there's no difference between sight, hearing, smell, taste, proprioreception, balance, proximity detection, etc. ALL are equally related to thought - ALL require similar types of brain processing to acquire.
No, two people experiencing the same stimulus will not have the same brain processes going on - though they often DO occur in the same areas of the brain. But no two people have the same history, the same background, the same DNA coding, the same spacetime location, the same quantum signature, etc. And there's another interesting thing about brains that comes into play here.
No two brains develop the same. Physically, yes - they are very similar. But they're like a room full of LEGOs, scattered about, with some vague instructions of how things MIGHT work, and some vague input from time to time about what we want to do. Some processes work better than others, but sometimes the brain develops processes that only work 'good enough' - or sometimes, not - and sometimes the brain develops processes that work amazingly well. Sometimes, the brain develops redundant processes; sometimes, it runs a single process on a single, tenuous path, and when something goes wrong, there's no back-up.
That controls language, too. Sure, there's some generic things that tend to be true as the brain develops language - but it's not always true. Like a million people studied to see what ice cream flavor they like, you'll see trends and patterns, but you'll also see anomalies.
Just an interesting observation. You're a spoken language thinker. That actually says a lot about you.
Let me ask you one more quick question - and this isn't being rude or silly or anything. When you read, if you're alone - do you catch yourselves sometimes breathing the words, or talking quietly to yourself? Does your tongue try to shape the words as you read, almost without you realizing it? I've heard this is true for, like, 70% of the world. Just curious.