Mental Models, Psychology Of
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Gentner, D. (2002). Mental models, Psychology of. In N. J. Smelser & P. B. Bates (Eds.), International Encyclopedia of the Social and Behavioral Sciences (pp. 9683-9687). Amsterdam: Elsevier Science. Mental Models, Psychology of configural description or a mixture of the two, and the study of mental models. One approach seeks rarely any other kind. to characterize the knowledge and processes that These questions are not just an issue of academic support understanding and reasoning in knowledge- interest. We have all often had frustrating experience rich domains. The other approach focuses on mental trying to understand verbal directions abut how to models as working-memory constructs that support get somewhere or trying to grasp the layout of an area logical reasoning (see Reasoning with Mental Models). by means of a map. Virtual reality is currently being This article focuses chiefly on the knowledge-based proposed as having great potential for training people, approach. e.g., soldiers, for tasks in new environments. However, Mental models are used in everyday reasoning. For with the present state-of-the-art it is difficult to build a example, if a glass of water is spilled on the table, good sense of the layout (a good mental map) of a people can rapidly mentally simulate the ensuing virtual world one is moving through. How to use these events, tracing the water through its course of falling media most effectively to enable the most desirable downward and spreading across the table, and in- mental map is a goal for future research. ferring with reasonable accuracy whether the water will go over the table’s edge onto the floor. People’s ability to infer and predict events goes well beyond their direct experience. For example, if asked ‘which Bibliography can you throw further, a potato or a potato chip?’ Bloom P, Peterson M A, Nadel L, Garrett M F (eds.) 1996 most people can give an answer immediately (the Language and Space. MIT Press, Cambridge, MA potato) even if they have never actually tossed either Gallistel C R 1990 The Organization of Learning. MIT Press, item. Cambridge, MA However, mental models are not always accurate. Gladwin T 1970 East is a Big Bird. Harvard University Press, Mental models researchers aim to capture human Cambridge, MA knowledge, including incorrect beliefs. The study of Hazen N L, Lockman J J, Pick H L Jr 1978 The development of children’s representations of large-scale environments. Cltild incorrect models is important for two reasons. First, Deuelopment 49: 623-36 the errors that a learner makes can help reveal what Hutchins E 1995 Cognition in the Wild. MIT Press, Cambridge, the learning processes must be.. Second, if typical MA incorrect models are understood, then instructors Hutchins E, Hinton G E 1984 Why the islands move. Perception and designers can create materials that minimize the 13629-32 changes of triggering errors. Lewis D 1978 The Voyaging Stars: Secrets of the Pacific Island A striking example of an incorrect mental model Nauigators. Norton, New York is the curdinear momentum error (Clement 1983, Loomis JM, Klatzky RL, Golledge RG, CicineIli JG, McCloskey 1983). When college students are asked: ‘If Pellegrino J W, Fry P A 1993 Nonvisual navigation by blind a ball a string is spun in a circle and then let go, and sighted: Assessment of path inkgrationability. Joumul of on Experimental Psychology: General 122: 73-91 what path will it take?’, many of them correctly say that Rieser J J, Guth D A, Hi11 E W 1988 Sensitivity to perspective the ball will travel at a tangent to the circle. However, structure while waking without vision. Perception 15 173-88 a fair proportion states that the ball will move in a Thorndyke P W, Hayes-Roth B 1982 Difierences in spatia1 curved path, retaining some of the curvilinear mo- knowledge acquired from maps and navigation. Cognitive mentum gained from being spun in a circle. The usual Psychology 14 56&89 intuition is that the ball will gradually lose this ‘curvi- Tversky B 1996 Spatial perspective in descriptions. In: Bloom P, linear momentum’, so that the path will straighten Peterson MA, Nadel L, Garrett M F (eds.) Language and out over time. This erroneous intuition is fairly Space. MIT Press, Cambridge, MA pp. 463-91 Tolman EC 1948 Cognitive maps in rats and men. Psycho- general; for example, the same error turns up when logical Review 56: 144-55 people are asked about the path of a ball blown Uttal DH 2001 Seeing the big picture: Map use and the through a circular tube. Further, the error does not development of spatial cognition. Developmental Science 3 yield immediately to training; it is found even in 247-86 students with a few years of physics. However, it does diminish with increasing expertise. H.L. Pick Jr. Another striking error is seen when people are asked what trajectory a ball will follow if it rolls off the edge of a table (McCloskey 1983). Instead of the correct answer, that the ball will fall in a parabolic path (Fig. la), many people believe the ball will continue traveling straight, and begin falling (either Mental Models, Psychology of straight down or in a curved path) only when its forward momentum begins to flag (Fig. IC and lb). A mental model is a representation of some domain People seem to believe that sufficient forward momen- or situation that supports understanding, reasoning, tum will overcome the tendency to fall. This error and prediction. There are two main approaches to is sometimes called ‘Roadrunner physics’ because it 9683 Mental Models, Psychology of **** ....I......* ** ..........*....., *** %* ****’.= . .: 8 . W . i O a Figure 1 Responses to the question ‘What path will the ball take after it rolls off the table? (adapted from McCloskey 1983) resembles the event in which a cartoon character runs chiefly linear temporal order, with limited inferential off a cliff but does not fall until some distance over flexibility. Nufve theories or folk theories are global the edge. However, McCloskey noted that the same systems of belief, typically encompassing larger error occurs in the writings of Jean Buridan and domains such as biOl9gY. The terms mental models and other fourteenth-century Aristotelian philosophers. It naibe or folk theories overlap in their application, appears that cartoon events were created to match a though mental models are typically more specific than mental model that arises naturally from experience, theories. possibly by overgeneralizing from experiences with linear momentum. Mental models can facilitate learning, particularly I, Characteristics of Mental Models when the structure of the new learning is consistent with the model, For example, Kieras and Bovair Mental models reasoning relies on quulitatwe relations, (1984) showed that subjects could operate a simulated rather than on quantitative relations. People can device more accurately and could diagnose malfunc- reason well about the fact that one quantity is less tions better when they had a causal mental model of its than another without invoking the precise values of functioning, rather than a merely procedural grasp of the quantities. This principle forms the basis for quali- how to operate it. Similarly, Gentner and Schumacher tative process theory, discussed below (Forbus 1984). (1986) showed that subjectswere better able to transfer Mental models often permit mental simulation: the an operating procedure from one device to another sense of being able to run a mental model internally, so when they had a causal mental model of the operation that one can observe how it will behave and what the of the first device, rather than just a set of procedures. outcome of the process will be. The processes that The degree of facilitation depended greatly on the underlie mental simulation are still under study. match between the original model and the new However, there is good evidence that people are able, material. within limits, to mentally simulate the behavior of a Mental models are used to explain human reasoning device, even if they are simply shown a static display about physical systems: devices and mechanisms (de (Hegarty and Just 1993). There is an apparent tradeoff Kleer and Brown 1983, Hegarty and Just 1993, Kieras between online simulation and retrieval of stored and Bovair 1984, Williams et al. 1983); electricity outcomes (Schwartz and Black 1996). As people (Gentner and Gentner 1983); the interactionsof people become familiar with a system, they no longer carry with computers and other devices (Norman 1988), and out full simulations of behavior in all cases, but knowledge of home heating systems (Kempton 1986). instead simply access their stored knowledge of the They have also been applied to spatial representation outcome. and navigation (Forbus 1995, Hutchins 1983, Tversky Another finding of mental models research is that 1991); ecology (Kempton et al. 1995), human popula- people are capable of holding two or more inconsistent tion growth (Gentner and Whitley 1997), and the models within the same domain, a pattern referred to development of astronomical knowledge (Vosniadou as pastiche models (Collins and Gentner 1987) or and Brewer 1992). knowledge in pikes (disessa 1982). For example, Mental models are related to several other kinds of Collins and Gentner (1987) found that many novice representational structures (see Markman 1999 for subjects had ‘pastiche’ models of evaporation. A a comprehensive discussion). Schemas (or schemata) novice learner may give one explanation of what are general belief structures. Scripts are schemas causes a towel to dry in the sun and a completely summarizing event sequences, characterized by a different explanation of what causes a puddle of water 9684 Mental Models, Psychology of h to evaporate, failing to see any connection between the 3. Analogies and Mental Models two phenomena.