Determining truth conditions in signaling games

Evolving signaling systems can be said to induce partitions on the space of world states as they approach equilibrium. Formalizing this claim provides a general framework for understanding what it means for language to “cut nature at its seams”. In order to avoid taking our current best science as providing the adaptive target for all evolving systems, the state space of the world must be characterized exclusively in terms of the coincidence of stimuli and payoffs that drives the evolution of cognitive complexity. Cognition exploits the reliable clustering of events in this space. Using this framework to analyze our ordinary concepts of truth and justification, it appears that while justification can be a simple matter of conforming to historically entrenched strategies, truth cannot be fully specified on the basis of the system’s causal history, but requires a robust clustering in the larger world state space.     

Shell games,information, and counterfactuals

Cohen and Meskin 2006 Cohen, Jonathan and Aaron, Meskin. 2006. An Objective Counterfactual Theory of Information. Australasian Journal of Philosophy, 84: 333–352. [Taylor &; Francis Online], [Web of Science ®] , [Google Scholar] have recently proposed a novel counterfactual account of information. I argue that it is a step down from its intended target, namely Dretske's 1981 Dretske, Fred. 1981. Knowledge and the Flow of Information, Cambridge Mass: MIT Press.  [Google Scholar] theory of information. Thinking of the information carried by signals in terms of counterfactuals leads to falsely diagnosing bona fide instances of information transmission as not being instances of information transmission at all, with major loss of explanatory power.     

Evolutionary dynamics of Lewis signaling games: signaling systems vs. partial pooling

Transfer of information between senders and receivers, of one kind or another, is essential to all life. David Lewis introduced a game theoretic model of the simplest case, where one sender and one receiver have pure common interest. How hard or easy is it for evolution to achieve information transfer in Lewis signaling?. The answers involve surprising subtleties. We discuss some if these in terms of evolutionary dynamics in both finite and infinite populations, with and without mutation.     

The role of neuronal signaling in controlling cerebral blood flow

Well-regulated blood flow within the brain is vital to normal function. The brain's requirement for sufficient blood flow is ensured by a tight link between neural activity and blood flow. The link between regional synaptic activity and regional cerebral blood flow, termed functional hyperemia, is the basis for several modern imaging techniques that have revolutionized the study of human brain activity. Here, we review the mechanisms of functional hyperemia and their implications for interpreting the blood oxygen level-dependent (BOLD) contrast signal used in functional magnetic resonance imaging (fMRI).     

EMOTLAB: Software for studying emotional signaling in economic bargaining games

EMOTLAB software creates a virtual social environment in which individuals interact via computer with a virtual interaction partner in a series of economic bargaining games. The virtual partner appears on the participant's computer screen as a digital image (e.g., video or picture file) during each trial. A key feature of EMOTLAB software is its ability to control both the strategic behavior and the emotion signaling behavior (e.g., anger vs. embarrassment) of the virtual interaction partner. By simply editing a series of text files that control the subroutines governing the different features of the experiment (payoff structure, number of trials, etc.), EMOTLAB can generate an essentially infinite number of different social bargaining situations in which participants earn monetary payoffs contingent upon their decisions. This paper provides an overview of this software and how one can edit various subroutines to generate a typical experimental session in which research participants encounter a virtual interaction partner who displays different emotional signals.     

Zeno and flow of information

Although the current literature on supertasks concentrates largely on their supposed physical implications (extending the tradition of Zeno’s classical paradoxes of movement), in this study I propose a new model of supertask that explores for the first time some of their information-related consequences and I defend these consequences from a possible criticism.     

A dynamic-epistemic hybrid logic for intentions and information changes in strategic games

In this paper I present a dynamic-epistemic hybrid logic for reasoning about information and intention changes in situations of strategic interaction. I provide a complete axiomatization for this logic, and then use it to study intentions-based transformations of decision problems.     

Horizontal information flow in spoken sentence production

In 4 experiments the authors used a variant of the picture-word interference paradigm to investigate whether there is a temporal overlap in the activation of words during sentence production and whether there is a flow of semantic and phonological information between them. Experiments 1 and 2 demonstrate that 2 semantically related nouns produce interference effects either when they are in the same or different phrases of a sentence. Experiments 3 and 4 demonstrate that 2 phonologically related nouns produce facilitation effects but only when they are within the same phrase of a sentence. The results argue against strictly serial models of multiple-word access and provide evidence of a flow of semantic and phonological information between words during sentence production.     

视频游戏中的化身认同

化身认同是个体在使用和体验游戏化身的过程中,自我知觉发生暂时性改变,并与化身在情绪和认知上的联系暂时加强的心理现象,它为理解化身效应提供了新视角。目前,化身认同的测量模型主要有三维和四维结构模型,其神经机制也得到初步揭示。影响化身认同的因素主要包括游戏自身特点和个体因素。影响效果方面,化身认同与游戏体验、游戏成瘾、攻击行为和自我同一性的关系是目前关注的焦点。未来的研究,仍需深入探讨化身认同的概念与结构,研发更加有效的测量工具,拓展研究方法,丰富研究变量,并加强应用研究。     

The role of direction information in the perception of geometric optic flow components

Theoretically, optic flow, an important source of information for the perception of locomotion and three-dimensional structure of the environment, is described in terms of divergence, curl, and shear components. We measured how the detection of the type of flow field depends on directional information. We manipulated the local directions by rotating them through an angle x relative to the original direction (i.e., the direction of motion at that locus in an unaltered flow field). The results of the first experiments showed that divergence, curl, and shear can be detected even if the directional range of the individual motion vectors is as broad as 180 degrees. Subsequent experiments revealed that the detection of the geometric components of the optic flow field is merely based on the integration of a few (10% of vectors) local directions correctly (within 10 degrees of original direction) specifying the type of flow field. Other directions are irrelevant to this process. This is actually what one would expect if the optic flow is analyzed by special purpose mechanisms that detect and process the geometric components on the basis of the integration of motion information. The results indicate that as far as they integrate motion information, detectors for divergence, curl, and shear operate in a similar manner. Implications of the results for modeling such mechanisms are discussed.     

The timing effect in public good games

In public good situations, expectations concerning other persons’ moves are important and subtle cues can affect these expectations. In Experiment 1, participants in a public good game who moved simultaneously made high contributions and expected their opponents to make high contributions. However, participants who moved pseudo-sequentially (one after the other, but without knowledge of the other’s decision) expected their opponents to make medium-sized contributions, but made almost no contribution themselves. In Experiment 2, we manipulated expectations experimentally. Participants who moved simultaneously reciprocated what they expected their partners to do. Participants who moved pseudo-sequentially defected, regardless of what they expected from their opponents. Furthermore, we found that simultaneous movers were more likely than pseudo-sequential movers to conceptualize themselves and the other player as a group. This sense of groupness seemed to account partly for their inclination to reciprocate anticipated behavior.     

The theory of games and psychoanalysis

The theory of games and psychoanalysis, traditionally, have gone separate conceptual ways. It is the point of this paper that a careful comparative look will reveal, in addition to the many imposing differences, an undeniable overlap suggesting an unsuspected dialectical relationship.     

Rationality and bounded information in repeated games, with application to the iterated Prisoner's Dilemma

Actions in a repeated game can in principle depend on all previous outcomes. Given this vast policy space, human players may often be forced to use heuristics that base actions on incomplete information, such as the outcomes of only the most recent trials. Here it is proven that such bounded rationality is often fully rational, in that the optimal policy based on some limited information about the game's history will be universally optimal (i.e., within the full policy space), provided that one's opponents are restricted to using this same information. It is then shown how this result allows explicit calculation of subgame-perfect equilibria (SPEs) for any repeated or stochastic game. The technique is applied to the iterated Prisoner's Dilemma for the case of 1-back memory. Two classes of SPEs are derived, which exhibit varying degrees of (individually rational) cooperation as a result of repeated interaction.     

Semantic and phonological information flow in the production lexicon

When speakers produce words, lexical access proceeds through semantic and phonological levels of processing. If phonological processing begins based on partial semantic information, processing is cascaded; otherwise, it is discrete. In standard models of lexical access, semantically processed words exert phonological effects only if processing is cascaded. In 3 experiments, speakers named pictures of objects with homophone names (ball), while auditory distractor words were heard beginning 150 ms prior to picture onset. Distractors speeded picture naming (compared with controls) only when related to the nondepicted meaning of the picture (e.g., dance), exhibiting an early phonological effect, thereby supporting the cascaded prediction. Distractors slowed picture naming when categorically (e.g., frisbee) related to the depicted picture meaning, but not when associatively (e.g., game) related to it. An interactive activation model is presented.     

The effects of representations and behavior in experimental games

This research shows that in an experimental game it is the perception of an actual relationship, of an interaction with the other person more than the nature of the game which creates a climate in which cooperative responses can be established. Cooperative sets can be induced through the Representation of the partner: a reactive partner promoting cooperation, and a rigid one promoting competition. In addition it is noted that in order to understand the reactions induced by the partner's behavior, the behavior in itself it not sufficient. Indeed it is interpreted and understood in terms of the initial representation. The analysis of a person's behavior when in relation with another, should be based on a joint study of the existing representations and of the actual behavior observed.     

Heading and path information from retinal flow in naturalistic environments

In four experiments, we explored the heading and path information available to observers as we simulated their locomotion through a cluttered environment while they fixated an object off to the side. Previously, we presented a theory about the information available and used in such situations. For such a theory to be valid, one must be sure of eye position, but we had been unable to monitor gaze systematically; in Experiment 1, we monitored eye position and found performance best when observers fixated the designated object at the center of the display. In Experiment 2, when we masked portions of the display, we found that performance generally matched the amount of display visible when scaled to retinal sensitivity. In Experiments 3 and 4, we then explored the metric of information about heading (nominal vs. absolute) available and found good nominal information but increasingly poor and biased absolute information as observers looked farther from the aimpoint. Part of the cause for this appears to be that some observers perceive that they have traversed a curved path even when taking a linear one. In all cases, we compared our results with those in the literature.     

Inconsistencies in extensive games

In certain finite extensive games with perfect information, Cristina Bicchieri (1989) derives a logical contradiction from the assumptions that players are rational and that they have common knowledge of the theory of the game. She argues that this may account for play outside the Nash equilibrium. She also claims that no inconsistency arises if the players have the minimal beliefs necessary to perform backward induction. We here show that another contradiction can be derived even with minimal beliefs, so there is no paradox of common knowledge specifically. These inconsistencies do not make play outside Nash equilibrium plausible, but rather indicate that the epistemic specification must incorporate a system for belief revision. Whether rationality is common knowledge is not the issue.     

The pyeTribe: Simultaneous eyetracking for economic games

The recent introduction of inexpensive eyetrackers has opened up a wealth of opportunities for researchers to study attention in interactive tasks. No software package has previously been available to help researchers exploit those opportunities. We created “the pyeTribe,” a software package that offers, among others, the following features: first, a communication platform between many eyetrackers to allow for simultaneous recording of multiple participants; second, the simultaneous calibration of multiple eyetrackers without the experimenter’s supervision; third, data collection restricted to periods of interest, thus reducing the volume of data and easing analysis. We used a standard economic game (the public goods game) to examine the data quality and demonstrate the potential of our software package. Moreover, we conducted a modeling analysis, which illustrates how combining process and behavioral data can improve models of human decision-making behavior in social situations. Our software is open source.