Thinking visually is often associated with the right half of the brain. The visual-spatial learner model is based on the newest discoveries in brain research about the different functions of the hemispheres. The left hemisphere is sequential, analytical, and time-oriented. The right hemisphere perceives the whole, synthesizes, and apprehends movement in space.
Picture thinking could be called "non-linguistic thinking", and people who do such information processing could be called "visual thinkers". It involves thinking beyond the definitions of language and has many personal referents to meaning which cannot be translated.
Picture thinking involves different categorization than verbal or linguistic processing. Linguistic thinking involves categorization of thought in defined, linear forms. It is serial, and it concentrates on detailed parts in the stimulus. Visual thinking involves categorization which is parallel and holistic. Though linguistic thinkers often feel that visual-thinkers concentrate on detail, in fact this occurs because of the extreme memory of picture thinkers. Much of the thinking of children in the pre operational stage (2-7 years of age) is visual. It is hypothesized that autistic people fail to develop other information processing capacity than visual thinking, and stay at this stage.