The enduring scandal of deduction

Deductive inference is usually regarded as being “tautological” or “analytical”: the information conveyed by the conclusion is contained in the information conveyed by the premises. This idea, however, clashes with the undecidability of first-order logic and with the (likely) intractability of Boolean logic. In this article, we address the problem both from the semantic and the proof-theoretical point of view. We propose a hierarchy of propositional logics that are all tractable (i.e. decidable in polynomial time), although by means of growing computational resources, and converge towards classical propositional logic. The underlying claim is that this hierarchy can be used to represent increasing levels of “depth” or “informativeness” of Boolean reasoning. Special attention is paid to the most basic logic in this hierarchy, the pure “intelim logic”, which satisfies all the requirements of a natural deduction system (allowing both introduction and elimination rules for each logical operator) while admitting of a feasible (quadratic) decision procedure. We argue that this logic is “analytic” in a particularly strict sense, in that it rules out any use of “virtual information”, which is chiefly responsible for the combinatorial explosion of standard classical systems. As a result, analyticity and tractability are reconciled and growing degrees of computational complexity are associated with the depth at which the use of virtual information is allowed.     

The enduring Rorschach contributions of David Rapaport

David Rapaport's contributions to the Rorschach are highlighted and placed within the context of his significant impact on psychological testing and psychoanalytic theory. After a brief biographical sketch, I examine the essence of Rapaport's lasting Rorschach contributions and summarize some of the strengths and limitations of the Rapaport Method.     

Dewey's enduring vitality

Conclusion There are many loose ends in this study and I shall make no effort to tie them together in some neat summary. I trust that my basic sympathies with Dewey have been clear throughout. What I have discovered in the course of writing this is that reflecting upon Dewey's work in the light of contemporary problems and schools of philosophy not only casts light on these problems and schools but enhances one's appreciation for the distinctiveness, coherence and value of his work.     

The effect of signaled reinforcement availability on concurrent performances in humans

During Phase I, three female human subjects pressed a button for monetary reinforcement in two-component concurrent variable-interval schedules. Five different reinforcement frequencies were used in component A, whereas the reinforcement frequency in component B was held constant. Absolute rates of responding conformed to equations proposed by Herrnstein to describe concurent performances, and the ratios of the response rates and the times spent in the two components conformed to the matching law. During Phase II, the availability of reinforcement in component A was signaled by the illumination of a lamp. This resulted in suppression of response rates in component A and elevation of response rates in component B, these changes being reflected in a distortion of the matching relationship which took the form of a bias in favor of component B.     

The enduring impact of transient emotions on decision making

People often do not realize they are being influenced by an incidental emotional state. As a result, decisions based on a fleeting incidental emotion can become the basis for future decisions and hence outlive the original cause for the behavior (i.e., the emotion itself). Using a sequence of ultimatum and dictator games, we provide empirical evidence for the enduring impact of transient emotions on economic decision making. Behavioral consistency and false consensus are presented as potential underlying processes.     

The effect of stimulus availability on task choice in voluntary task switching

The voluntary task switching paradigm allows subjects to choose which task to perform on each trial in a stimulus environment affording multiple tasks. The present study examined the effect of stimulus availability on task choice. Subjects viewed displays containing a digit and a letter and performed either an even/odd or a consonant/vowel judgment on each trial. The target stimuli appeared with a stimulus onset asynchrony (SOA) of 0, 50, 100, or 150 msec. The probability of performing the task associated with Stimulus 1 increased as SOA increased, indicating an effect of external or stimulus-driven factors on task choice. This effect of stimulus availability on task choice was greater when the response-stimulus interval was 400 msec than when it was 2,000 msec. This interaction of preparation interval and stimulus availability is explained within a model of task choice that includes both internal processes and external influences.     

The concreteness effect: evidence for dual coding and context availability

The term concreteness effect refers to the observation that concrete nouns are processed faster and more accurately than abstract nouns in a variety of cognitive tasks. Two models have been proposed to explain the neuronal basis of the concreteness effect. The dual-coding theory attributes the advantage to the access of a right hemisphere image based system in addition to a verbal system by concrete words. The context availability theory argues that concrete words activate a broader contextual verbal support, which results in faster processing, but do not access a distinct image based system. We used event-related fMRI to detect the brain regions that subserve to the concreteness effect. We found greater activation in the lower right and left parietal lobes, in the left inferior frontal lobe and in the precuneus during encoding of concrete compared to abstract nouns. This makes a single exclusive theory unlikely and rather suggests a combination of both models. Superior encoding of concrete words in the present study may result from (1) greater verbal context resources reflected by the activation of left parietal and frontal associative areas, and (2) the additional activation of a non-verbal, perhaps spatial imagery-based system, in the right parietal lobe.     

The enduring presence of Heinz Kohut: empathy and its vicissitudes

This paper expands upon and further develops the centrality of empathy in psychoanalysis as offered by Heinz Kohut. Using clinical examples, it differentiates sustained empathy as the distinctive component of psychoanalysis, and it demonstrates some of the difficulties in determining the boundaries of empathy in the practice of psychoanalysis. A further distinction is from mind reading, a purely cognitive exercise, as is intuition (Carruthers 2009). To pursue a psychoanalytic perception of empathy one must confront its limitations and go beyond the somewhat simplistic claim of its unquestioned therapeutic effect. Empathy is more than a cognitive act, and as sustained over time it can be difficult to achieve, can be misunderstood, and can at times have no therapeutic effect.     

The effect of practice on component submovements is dependent on the availability of visual feedback

Participants (N = 16) were given extensive practice (1,500 trials) on a perceptual-motor aiming task. The full-vision (FV) group practiced with vision of their response cursor, whereas the no-vision (NV) group practiced in a condition without vision. Movements were made as quickly and accurately as possible, and knowledge of results (KR) was provided. The authors tested the importance of vision early and late in practice by transferring participants to the NV condition without KR. The effects of practice differed between the two conditions. The FV group increased the speed of initial impulse to get to the target quickly, then relied on vision to make discrete error corrections. Transfer tests revealed that reliance on vision remained after extensive practice. For the NV group, practice effects were associated with a reduction in the extent to which discrete error corrections were produced.     

Early isolation produces enduring hyperactivity in the rat, but no effect upon spontaneous alternation

Rearing rats in isolation between 23 and 45 days caused a lasting increase in photocell-cage activity, even if the animals were subsequently rehoused in social groups until 125 days of age. In contrast to its effects upon activity, isolation had no effect upon spontaneous alternation in a Y-maze. This dissociation argues for caution in relating hyperactivity and reduced alternation to a unitary deficit in an inhibitory system.     

Influence of color word availability on the Stroop color-naming effect

Three experiments tested whether the Stroop color-naming effect is a consequence of word recognition's being automatic or of the color word's capturing visual attention. In Experiment 1, a color bar was presented at fixation as the color carrier, with color and neutral words presented in locations above or below the color bar; Experiment 2 was similar, except that the color carrier could occur in one of the peripheral locations and the color word at fixation. The Stroop effect increased as display duration increased, and the Stroop dilution effect (a reduced Stroop effect when a neutral word is also present) was an approximately constant proportion of the Stroop effect at all display durations, regardless of whether the color bar or color word was at fixation. In Experiment 3, the interval between the onsets of the to-be-named color and the color word was manipulated. The Stroop effect decreased with increasing delay of the color word onset, but the absolute amount of Stroop dilution produced by the neutral word increased. This study's results imply that an attention shift from the color carrier to the color word is an important factor modulating the size of the Stroop effect.     

Retrieving enduring spatial representations after disorientation

Four experiments tested whether there are enduring spatial representations of objects' locations in memory. Previous studies have shown that under certain conditions the internal consistency of pointing to objects using memory is disrupted by disorientation. This disorientation effect has been attributed to an absence of or to imprecise enduring spatial representations of objects' locations. Experiment 1 replicated the standard disorientation effect. Participants learned locations of objects in an irregular layout and then pointed to objects after physically turning to face an object and after disorientation. The expected disorientation was observed. In Experiment 2, after disorientation, participants were asked to imagine they were facing the original learning direction and then physically turned to adopt the test orientation. In Experiment 3, after disorientation, participants turned to adopt the test orientation and then were informed of the original viewing direction by the experimenter. A disorientation effect was not observed in Experiment 2 or 3. In Experiment 4, after disorientation, participants turned to face the test orientation but were not told the original learning orientation. As in Experiment 1, a disorientation effect was observed. These results suggest that there are enduring spatial representations of objects' locations specified in terms of a spatial reference direction parallel to the learning view, and that the disorientation effect is caused by uncertainty in recovering the spatial reference direction relative to the testing orientation following disorientation.     

The role of body-based sensory information in the acquisition of enduring spatial representations

Although many previous studies have shown that body-based sensory modalities such as vestibular, kinesthetic, and efferent information are useful for acquiring spatial information about one's immediate environment, relatively little work has examined how these modalities affect the acquisition of long-term spatial memory. Three groups of participants learned locations along a 146 m indoor route, and subsequently pointed to these locations, estimated distances between them, and constructed maps of the environment. One group had access to visual, proprioceptive, and inertial information, another had access to matched visual and matched inertial information, and another had access only to matched visual information. In contrast to previous findings examining transient, online spatial representations, our results showed very few differences among groups in the accuracy of the spatial memories acquired. The only difference was the improved pointing accuracy of participants who had access to proprioceptive information relative to that of participants in the other conditions. Results are discussed in terms of differential sensory contributions to transient and enduring spatial representations.     

The effect of the availability of a dynamic model on the acquisition of a complex cyclical action

This study examines the effect of the availability of a dynamic model on the acquisition of a complex cyclical action: slalom-type ski movements on a ski-simulator. A two-condition design was used, with N = 20 subjects per condition. In the experimental condition subjects had, during training trials, the benefit of the availability of a dynamic (video) model of an expert performer, while subjects in the control condition were left entirely to “discovery learning”. The dependent variables were the amplitude, frequency and fluency of the movement of the ski-simulator platform on which subjects were required to stand in operating the simulator. Movement characteristics of the platform were recorded by means of a microcomputer (Apple II+) coupled to a Selcom 403 camera (SELSPOT system). Subjects having the benefit of a dynamic model during training were shown, at the end of the five-day training period, to produce more fluent movements (of the platform) and to show greater consistency of fluency and of tempo than subjects left entirely to discovery learning. The results are discussed in the context of theories of perception and of motor learning.     

The context of clinical judgment: The effect of resource availability on judgments of amenability to treatment in juvenile offenders

Conclusion The present study demonstrates that the contextual factors of resource availability and agency setting may have a significant, systematic relationship to assessments of potential treatment outcome. The value of this finding is not to debunk the idea of the objective clinician one more time but, instead, to provide leads regarding the possible factors worth further investigation in constructing models of clinical judgment. We are aware that clinicians do not necessarily optimize (Simon, 1976) when making treatment recommendations, but we know very little about the influences that structure the clinician's compromises in clinical judgment. A clearer understanding of this judgment process may come, however, as a result of applying a model that considers the clinician as a practitioner of human judgment, much of which is an adapative response to contextual influences (Hogarth, 1981; Nisbett & Ross, 1980).This research was part of the first author's doctoral dissertation and funded by a grant from the National Institute of Mental Health (MH-8792-01). The authors thank Jean Ann Linney, John Monahan, and Walter Wadlington for their helpful comments, and the Center for the Study of Law and Children (especially Elizabeth Scott and Richard Bonnie) at the University of Virginia for support and guidance.