Figure 2. Relationships between Offline Trust and Online Customers’ Mental Model

Note: Dotted line box indicates constructs not in this study

Cognitive overhead, on the other hand, is the additional effort and concentration users need to perform one or more complex tasks at once [17]. Cognitive overhead is influenced by orientation, navigation and interface design [101]. For example, multimedia overkill in a Web interface (e.g., excessive graphics, color, animation, sound) can cause excessive cognitive overhead because the capacity for human information processing is limited. We thus argue that various website design factors affect both coherence and cognitive overhead.
Based on Thuring et al. [101], this study argues that flow and structural assurance affect perceived website satisfaction and extent of use through coherence and cognitive overhead. While this study does not measure coherence and cognitive overhead, it argues that flow and structural assurance partly influence the Figure 2 outcomes by their effects on coherence and cognitive overhead. Flow means an optimal experience with a task [20]. Structural assurance means the belief that situational factors like contracts, regulations and guarantees support the likelihood of success [71]. Using both coherence/cognitive overhead and their causes (flow and structural assurance) in the model seemed like overkill in terms of model complexity. Also, because it is viable to test a subset of a larger theoretical model [99], we chose to test a model that only included flow and structural assurance.