The smallest structural unit of the mind is representation. A representation shows a feature like a fractal. No matter how you break it into parts, a "relation" (representation) will always be re-existent, and this process will deeply persist through the characteristic differences in repeating itself but not losing its character as to be a representation at every turn. Besides that, every mental representation is in a non-linear web within all other representations as a whole. In short, in the mind all roads may not lead to Rome!
We can explain the formation of representational structures with dual appearances of the same mental process: similarity (integration) and dissimilarity (disintegration). At this point, we have to explain basic acts of the mind which reveal the dual appearances of this process: inhibition and excitation. But we still do not explain with these concepts that why a representation has to be in a certain kind of relational stream through other representations.
The awareness of how the world should be presented in a certain situation (a formative constraint) is needed. Awareness is a temporal answer or a series of answers that is functionally given by the system to the question "how the inter-representations relations should be." But we still cannot explain the chemistry of this answer with only mental stuffs; in the opposite case, there might be nothing in our hands besides of a simple tautology.