The theory that people are either left-brained or right-brained, meaning that one side of their brain is dominant, is based on the fact that the brain’s two hemispheres function differently. The left hemisphere is more analytical and methodical in its thinking, while the right hemisphere is more visual, intuitive, and creative. However, this theory has been debunked by neuroscientists who argue that both hemispheres of the brain are involved in most tasks, including creative ones.

A study conducted on jazz guitarists found that creativity is primarily driven by the right hemisphere in musicians who are comparatively inexperienced at improvisation. However, musicians who are highly experienced at improvisation rely primarily on their left hemisphere. This suggests that creativity is a "right-brain ability" when a person deals with an unfamiliar situation but that creativity draws on well-learned, left-hemisphere routines when a person is experienced at the task.

Overall, creativity is a whole-brain process that utilizes all of the brains specialized capabilities. The brain is an electrochemical organ that works on the basis of neural activity that occurs in the cortex, and there are four main structures in the brain with a "thinking like" cortex. Two of them are the left hemisphere and the right hemisphere. The other two are the left half of the limbic system and the right half of the limbic system. From a left-brain/right-brain perspective, the creative process can be diagnosed as follows: interest (left and right), preparation (left), incubation (right), illumination (right), verification (left), and application (left and right). It is a balanced process, with four "lefts" and four "rights".

In summary, while the right hemisphere of the brain is often associated with creativity, both hemispheres are involved in most tasks, including creative ones.