"The Visceral Level is pre-consciousness, pre-thought. This is where appearance matters and first impressions are formed. Visceral design is about the initial impact of a product, about its appearance, touch and feel.
The behavioral itself has many facets: function, performance, and usability. A product’s function specifies what activities it supports, what it is meant to do – if the functions are inadequate or of no interest, the product is of little value. Performance is about how well the product does those desired functions – if the performance is inadequate, the product fails. Usability describes the ease with which the user of the product can understand how it works and how to get it to perform. Confuse or frustrate the person who is using the product and negative emotions result. But if the product does what is needed, if it is fun and easy to satisfy goals with it, the result is warm, positive affect.
It is only the reflective level that consciousness and the highest levels of feeling, emotions, and cognition reside. It is only here that the full impact of both thought and emotions are experienced. At the lower visceral and behavioral levels, there is only affect, but without interpretation or consciousness. Interpretation, understanding, and reasoning come from the reflective level.
Of the three levels, the reflective one is the most vulnerable to variability through culture, experience, education, and individual differences. This level can also override the others."
Norman, D. A.