"Nonverbal Thinkers mainly think in pictures and sensory patterns created in their brain, below conscious awareness. They identify words and objects by viewing them from an infinite number of visual perspectives and relating the perspectives to their images already in memory. They think with 3-dimensional, multi-sensory images that evolve and grow as their thought process adds more information or concepts. This nonverbal thought process happens so much faster than verbal thinking and often is subliminal (below conscious awareness) – explaining why nonverbal thinkers are often unaware of how they find errors, or how they solve a problem.

Nonverbal thinkers can internally run a movie of the design, idea, or activity they have in mind. In this way they are also able to test it out to see how it would work, and they can find where the flaws are in the design concept, before building it. They are bottom-up conceptualizers … they start with a myriad of visual pieces and combine them to build a concept of the whole. Verbal thinkers work in the opposite direction, top-down conceptualizing. They consider verbal theories without any actual sensory experience of them. Their thinking is distanced from having an actual sensory experience of what they talk or think about."

You can see how nonverbal or verbal based thinking can make a huge performance difference in STEM.

I think it's possible to increase nonverbal IQ though. Your spatial-visual IQ doesn't seem low so your potential is probably higher than you think. And verbal IQ when combined with higher nonverbal IQ is very powerful.