This work investigates how consumers make preference judgments when taking into account both product form and function. In prior work, where aesthetic preference is quantified using visual conjoint methods, aesthetic preference and functional preference were handled separately. Here, we introduce a new methodology, metaconjoint analysis, for testing the hypothesis that when consumers make decisions taking into account both a product's form and its function they employ a more complex decision-making strategy than when basing their decisions on form or function alone. We anticipate that this strategy will involve both analytical and emotional processes. When compared with participant ratings of form and function combinations across 28 subjects, the metaconjoint model is shown to have a correlation that was not statistically different from an additive model of form and function. However, unlike the additive model, the metaconjoint model gave additional information about how participants make tradeoffs between form and function. Next, we developed a novel paradigm using functional magnetic resonance imaging (fMRI) to determine what parts of the brain are primarily involved with a given tradeoff between form and function. While in the scanner, study participants were asked to make decisions in trials where only form varied, where only function varied, and where both form and function varied. Results from 14 participants suggest that choices based on products that vary in both form and function involve some unique and some common brain networks as compared to choices based on form or function alone; notably, emotion-related regions are activated during these complex decisions where form and function are in conflict. These results are consistent with the inclusion of emotion in decision-making with regards to product choice and demonstrate the feasibility of using fMRI to address questions about the mental processes underlying consumer decisions. Studying preference decisions together with their accompanying neurological activity will give engineers and designers greater insight into the consumer decision-making process.