Hi MP,

You describe well a traditional model of design cognition -

"Cognition is a complex process that involves imagination and
visualisation. Imagination includes the internal constructs in
"cognitive space" such as maps, diagrams, forms, models etc., held in
the mind, that can combine with memory and existing knowledge and it is
aided and reinforced by the external manifestation in the form of
external models , visualisations and numerous forms of external
representations that are created during the process of design
development, as iterations that inform the growing and transforming
progressive internal model. At each iteration some decisions are tested
and the resulting synthesis is examined as a whole and in its details in
a process of "Informed Synthesis". Groups can participate in this
process due to the effectiveness of the external models that help bring
coherence and congruence to the various cognitive models held by the
individuals in the group."

This moves things along nicely.

The reality, however, seems to be that this is not how cognition works biologically and is now being replaced by physiological models  that give a much greater role to the physiological body-based proicesses of consciousness, feeling and emotion. The cognition you describe are based on what we appear to see inside ourselves when we focus on outr own thinking. It appears that that it has limited validity as it seems that we a re not too good at seeing how we think (oops false consciousness again!) 

The physical reality is that it is the somato-sensory-motor system running our homeostatic management that is the main show with the imagogenic processes (thoughts in the mind) dictated by it and perhaps best regarded as the fluff on the top! This is not to ignore it or demean its role, simply to point out that it is these other deeper body-based physical systems that do most of the design cognition, creative thought making, allegory, judgement and optimisation etc. 

I put together a  precis of Damasio's findings in this area  and a short analysis of how they relate to design cognition for the Design Sense and Sensibility Conference at UNIDCOM/IADE in Lisbon last year. You might find it interesting? The preprint should be on my website - oops, just noticed its not there yet. I'll sort it out overnight. 

Best wishes,

Terry