On occasion I notice that I am thinking without language, although these moments tend to be brief and the thoughts tend to be not complex and often they are things I have pretty much rote memorized. It is also possible that the language is not as 'loud' in my mind as it usually is, so I don't even notice it.I find that if I repeat a phrase in my mind that I can already know what I am going to think prior to thinking it. Or if I think about a phrase that I already know, there is no reason for me to say the entire thing in my mind. Also I obviously think some without language, it is not like I use language to tell myself I am hungry prior to getting some food, and I do not use language to control my hands as they type on the keyboard. Clearly at some level I have decided to type on the keyboard, but I am not verbally telling myself to do so. Of course it is also possible to think in pictures, although I rarely do this I am able to think much more complex things than I can by thinking without either language or images. Repeat a phrase in your mind over and over to block your ability to think in language, and visualize something happening. You can think without language in such a way, unless you consider the visual images to be a form of language. I imagine that people who are born deaf very commonly think without language, either that or they visualize sign language or writing. They definitely don't think in verbal language though, because they have no idea what it sounds like. There are already ways to test for visual intelligence. Any persons IQ is the composite of their verbal and visual sub IQ scores. The IQ score we usually discuss is technically called GIQ, general intelligence quotient. When somebody has their IQ tested there are usually at least four sub scores that are taken into account, working visual memory and long term visual memory, working verbal memory and long term verbal memory. The average person has verbal and visual intelligence near 100 for each, and the average composite score is 100.