P. N. Johnson-Laird and R. M. J. Byrne proposed an influential theory of conditionals in which mental models represent logical possibilities and inferences are drawn from the extensions of possibilities that are used to represent conditionals. In this article, the authors argue that the extensional semantics underlying this theory is equivalent to…

Within lay explanation of actions, several significant inferences are assumed to follow from the partition between endogenous and exogenous attributions. An endogenous action is judged to constitute an end in itself; an exogenous action is judged to serve as a means to some further end. (Editor/RK)

It is proposed that many phenomena of human hypothesis testing can be understood in terms of a general positive test strategy. With this strategy, there is a tendency to test cases that are expected to have the property of interest rather than those expected to lack that property. (Author/LMO)

The use of the terms "sensitivity, threshold, bias, and ratio scale" in psychophysics is discussed, with special reference to the statistical decision theory of sensory discrimination and its application to signal detection and classical psychophysical procedures. (Editor)

Attempts to apply a chronometric analysis to the tendency of the visual modality to dominate conscious judgments about the presence and location of objects. (Author/RK)

It is pointed out that interpretation of learning set data will be easier and more informative if one uses a "first-order" problem, that is, one which can be solved on the first trial at the end of training. (Editor)

This article describes a theory of computations underlying the selection of coordinated motion patterns, especially in reaching tasks. The central idea is that stored postures are evaluated for the contributions they make to reaching a spatial target. The model explains a number of aspects of movement kinematics. (SLD)

A new theory of subjective probability is presented. According to this theory, different descriptions of the same event can give rise to different judgments. Experimental evidence supporting this theory is summarized, demonstrating that the theory provides a unified treatment of a wide range of empirical findings. (SLD)

Current theories and research on distributed activation in sleep are reviewed, and a neurocognitive theory of sleep is presented that is based on distributed activation. Neural and cognitive relationships described by the theory are translated into connectionist models, and simulations are described. (SLD)

A psychological theory of the logical particle "if" is presented that consists of a lexical entry, a set of pragmatic comprehension processes, and a reasoning program. The core of the theory is two inference schemas originally proposed by logicians. The theory can account for available data from children and adults. (SLD)

Results of investigations into associative priming are summarized and the relative strengths of spreading activation and nonspreading activation theories of priming are assessed. The explanatory power of spreading-activation theories is at least as great as that of nonspreading-activation theories. (SLD)

Placing psychology in a biological and physical context, James J. Gibson performed prophetic work on visual motion, inspiring more recent studies on higher order aspects of motion encoding. Although not always fully acknowledged, Gibson's work is very important to the development of perceptual psychology. (SLD)

Revision-of-opinion literature has generally found subjective probability judgments to be conservative (underconfident), whereas calibration literature has generally found judgment to be overconfident. Reanalysis of three previous studies shows how such data can coexist and reveals the effects of methodology on judgment interpretations. (SLD)

Recently, language has acquired theoretical importance as the medium of causal thinking. A discursive action model of description and attribution is presented that argues that causal attributions can be studied as social acts performed in discourse and not merely as cognitions about social acts that happen to be expressed in conversation. (SLD)

A new theory for discrete motor learning was proposed that seemed capable of explaining a number of closed-loop postulations. (Editor/RK)