Intentionality detection and “mindreading”: Why does game form matter?

Abstract

, we find consistent differences in behavior between the normal and extensive forms. In particular, we observe attempts to cooperate, and in some treatments we observe the achievement of cooperation, occurring more frequently in the extensive form. Cooperation in this context requires reciprocity, which is more difficult to achieve by means of intentionality detection in the normal as opposed to the extensive form games we study. Our objective is to study behavior in the normal form representation of one of two extensive form bargaining games previously examined by using a variety of matching protocols (1). In the current study we limit the matching protocols to single play and to repeat play with the same pairs, and we study comparisons of the normal and extensive forms.Comparisons of behavior in the normal and extensive forms of various games have been made most notably in refs. 2 and 3. The latter's emphasis is on the rationality principles of iterated dominance and backward induction as factors in individual behavior in addition to whether behavior in a game is invariant to the form of its representation-all fundamental principles in game theory (4). Rapoport (2) and Schotter et al. (3) strongly rejected the invariance principle, but explication in terms of game theory was illusive: ''where we expected our rationality principles would predict behavioral differences across game forms, either no such differences appeared or they were not what we expected.' ' (ref. 3, pp. 446-447).Rapoport (2) provides transparent examples of two extensive form versions of the ''Battle-of-the Sexes'' game and the same game in matrix normal (strategic) form. His examples make clear how order-of-play information provides a principle that can better coordinate player strategies in the extensive forms. That principle, as we would describe it, derives from the human capacity to read another person's thoughts or intentions by placing themselves in the position and information state of the other person. Because of the example's transparency and special character, his experiments are conducted by using a three-person resource dilemma, a public good, and a pure coordination game.In our games we try to predict certain core features of the variation in behavior with the game form, but only by reaching outside of the traditional rationality principles of game theory to include concepts of reciprocity and ''mindreading,'' from evolutionary psychology. Our ultimate goal is to provide an empirical foundation for modeling this behavior in terms of distributions of types of player-some of whom have a disposition toward noncooperative behavior, whereas others are disposed toward cooperation.Our wellsprings are hardly new. The essence of our conceptual approach was stated 38 years ago: ''A normative theory must produce strategies that are at least as good as what people can do without them. More, it must not deny or expunge details of the game that can demonstrably benefit two or more players and that the players, consequently, should not expunge...

Encoding-Specific Effects of Social Cognition on the Neural Correlates of Subsequent Memory

“…Activity in the medial PFC has repeatedly been observed during other social-cognitive tasks that require participants to understand the mental states of other people, such as judging whether a historical figure would understand the use of various objects (Goel et al, 1995), understanding stories involving deception and pretense (Fletcher et al, 1995), making inferences about the mental states of characters in cartoons or stories (Gallagher et al, 2000), and playing interactive games that require secondguessing one's opponent (McCabe et al, 2000;Gallagher et al, 2002). Likewise, studies of neuropsychological patients with damage to the medial PFC have suggested specific social-cognitive deficits, including inappropriate social behavior and a lack of social awareness (Damasio, 1994;Bozeat et al, 2000;Gregory et al, 2002;Rankin et al, 2003;Salmon et al, 2003).…”

Modularity and the Social Mind

“…However, if systems with different functions-and, therefore, computations-are deployed in a context-dependent way, then consistency might not be observed because different systems will embody different preferences. For example, the exact same game (from a mathematical standpoint) is played differently if it is presented as a grid as opposed to a tree structure (Rapoport, 1997;Schelling, 1960;Schotter, Weigelt, & Wilson, 1994), possibly because the latter format recruits one's "theory of mind" (Baron-Cohen, 1995) to a greater extent than the former (McCabe, Smith, & LePore, 2000). In a similar manner, in the context of choices among gambles, people have been shown to violate transitivity, preferring A to B and B to C, but also C to A (Tversky, 1969), possibly because different pairs of choices activate different evaluative systems.…”

Playing both roles in the trust game

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