Jonassen and Henning (1999) advance the notion of schema theory to incorporate natural tasks and situations as the foundations of mental models representing knowledge. Jonassen and Henning provide a definition of mental models that emphasizes structure and relationships as critical features: “Mental models are representations of objects or events in systems and the structural relationships between those objects and events” (p. 37).
Jonassen and Henning (1999) propose that learners model new knowledge through the adoption of allegory or metaphor to aid in structure mapping. They also suggest that structure mapping is an effective concept in understanding cognitive structure as long as five assumptions are taken into account:
- Mental models are internal representations.
- Mental models are linguistically mediated.
- Mental models are networks of concepts. Propositions in the cognitive structure are grouped together, as Ausubel (1968) suggests, around anchoring notions that in turn are formed together into substructures which assume a place in successively more inclusive and complex groupings.
- Concept meaning is embedded in relationships to other concepts. Jonassen and Henning suggest that the structural position of a concept with reference to others is another significant and critical dimension of its meaning that plays an integral role in the encoding and recall processes.
- Social meaning is the intersection of individual models. Variations in experience, prior knowledge, beliefs, and abilities account for individual differences in cognitive structure, but the common elements in congruence among a number of individuals assume a significance that is important to successful social discourse. Additionally, the collective awareness of knowledge that is held in common among individuals in a group itself affects the internal structural properties of the representation of that knowledge. (Jonassen & Henning, 1999)
Another critical feature affecting the efficacy of mental models according to Jonassen and Henning (1999) is the degree to which the models can be run. They suggest that learners with poor mental models are unable to run them when they are required and perform poorly in problem-solving tasks that rely on the models as the result (Jonassen & Henning). In order to run mental models, they must be dynamic, multimodal, and multidimensional (Jonassen & Henning).
Jonassen and Henning (1999) describe the dynamic properties of mental models using analogous explanations such as the shifting of focus, activating the model, or setting attention to describe transitions of state that the learner's mental model undergoes in response to the requirements of the moment. Modes of operation or awareness also play a role in the runnability of a particular mental model. Different contexts or states of activation at the moment new information is introduced may affect what portion of the learner's cognitive structure processes it (Jonassen & Henning, 1999).
The same element of information may play an important role in a number of interconnected submodels in the learner's cognitive structure (Jonassen & Henning, 1999). The more roles the same information plays, Jonaasen and Henning suggest, the more likely it is to become a stable point in the learner's cognitive structure. However, some substructures will be better rehearsed and more stable than others. The runnability of a new model may depend on the direction the cognitive process takes at critical intersections between new knowledge and existing structures (Jonassen & Henning).
Jonassen and Henning (1999) conclude that differences in knowledge structure, visualization capability, and the generation of metaphors account for significant differences in problem-solving abilities among individuals. Furthermore, they conclude that mental models with more linear structures, lower dimensionality, and less robust metaphors negatively affect the individual's problem-solving ability in a given knowledge domain (Jonassen & Henning).