In her article Creativity as a Neuroscientific Mystery (in the book Neuroscience of Creativity, MIT Press, 2013), Researcher Margaret A. Boden described 3 types of creative idea generation processes, and I added a fourth one here.
Due to the apparent "accidental" nature of idea generation, creativity is often treated as unpredictable. However, science has been researching the processes leading to creativity, and offered neuroscientific explanation to one of them. In fact, there are three, distinguished by the sorts of psychological, cognitive processes involved in idea generation for each of them. They are: combinational, exploratory, and transformational creativity. At the end of this article I added a fourth one: team-based combinational creativity.
This one is the most researched type by neuroscience. There are several explanations to the cognitive and brain functions that take place to generate combinational ideas. It is defined as the generation of new ideas through the combination of old ideas. There are four generally accepted steps to generate combinational ideas: collect as many old ideas as possible, let them incubate in your brain, force a trigger event, and finally engage in a relaxing activity (such as the shower) that will allow combinations to occur and generate new ideas. The premise for this type of creativity process is that the old ideas are already in your brain, and the focus of neuroscientific research is on the brain activity that leads to making those connections.
While still guided by old ideas in your brain, this method suggest exploring beyond what you know. Experimentation without knowing what the outcome will be, and curiosity for the unexpected will lead to ideas that could not have been generated through simple combinations of old ideas already in your brain. Unlike combinational creativity, the area of exploratory creativity was not as much researched by neuroscience. The premise of exploratory creativity is that the new idea is not in your head yet, but that ideas already in your head would only lead you to explore beyond them.
Boden defined transformational creativity ideas as impossibilist (don't bother looking it up, it's not a real word...) surprise. It begins by changing "the rules of the game." You have to take one (or more) of the rules that prevent you from generating new ideas and ask yourself what would happen, or what would be possible if that rule did not exist. One example would be the 1985 hypothesis that some carbon molecules are hollow spheres, opposite to common knowledge. Pursuing that theory led to the development of carbon nano-tubes and nanotechnology, and to a Nobel prize in 1996. Boden believes that transformational creativity generates the most radical ideas, the ones that have the likelihood of winning a Nobel prize, but also that those are very rare (transformational ideas. But also winning a Nobel prize...) Like exploratory creativity, neuroscience is in its very early days of understanding and explaining transformational creativity. The premise of transformational creativity is assuming (or hypothesizing) that an idea (or a few) in your head are actually wrong, and exploring the possibilities that result from accepting it.
While each method can lead to the generation of new creative ideas, Boden suggested that in reality you may be using a combination of all three methods. At least if you start with the higher-order methods (such as transformational or exploratory), you will complement them by using the lower-order methods (all the way down to combinational creativity).
At this point I would like to add a fourth method that belongs here--the team-based combinational creativity. The 3 processes described above rely on creative ideas generated in one brain of one person. However, ideas can also be generated by a team of creative people, with the right diversity, and the right dynamics, by which the old ideas, pieces of the new idea, actually reside with multiple people, and the team dynamics, through debate and communications will generate the combination. This method of idea generation is not the focus of neuroscience, as it occurs in multiple brains at the same time, and is more the focus of communications and social studies.
To maximize your creativity, you should pursue all four methods.