The wagon-wheel illusion in continuous light

The fact that a perceptual experience akin to the familiar wagon-wheel illusion in movies and on TV can occur in the absence of stroboscopic presentation is intriguing because of its relevance to visuo-temporal parsing. The wagon-wheel effect in continuous light has also been the source of considerable misunderstanding and dispute, as is apparent in a series of recent papers. Here we review this potentially confusing evidence and suggest how it should be interpreted.     

Cognitive approaches to posttraumatic stress disorder: the evolution of multirepresentational theorizing

The evolution of multirepresentational cognitive theorizing in psychopathology is illustrated by detailed discussion and analysis of a number of prototypical models of posttraumatic stress disorder (PTSD). Network and schema theories, which focus on a single, explicit aspect/format of mental representation, are compared with theories that focus on 2 or more explicit representational elements. The author argues that the latter theories provide a more complete account of PTSD data, though are not without their problems. Specifically, it is proposed that at least 3 separate representational elements-associative networks, verbal/propositional representations, and schemas-are required to generate a comprehensive cognitive theory of PTSD. The argument that the development of multirepresentational cognitive theory in PTSD is a paradigm case for the development of similar theories in other forms of psychopathology is elaborated, and a brief agenda is proposed promoting 2 levels of theorizing-deep, formal theory alongside more localized, applied theory.     

Core mechanisms in "theory of mind"

Our ability to understand the thoughts and feelings of other people does not initially develop as a theory but as a mechanism. The "theory of mind" mechanism (ToMM) is part of the core architecture of the human brain, and is specialized for learning about mental states. Impaired development of this mechanism can have drastic effects on social learning, seen most strikingly in the autistic spectrum disorders. ToMM kick-starts belief-desire attribution but effective reasoning about belief contents depends on a process of selection by inhibition. This selection process (SP) develops slowly through the preschool period and well beyond. By modeling the ToMM-SP as mechanisms of selective attention, we have uncovered new empirical phenomena. We propose that early "theory of mind" is a modular-heuristic process of domain-specific learning.     

Negative self-imagery in social anxiety contaminates social interactions

Patients with social phobia report experiencing negative images of themselves performing poorly when in feared social situations. The present study investigates whether such negative self-imagery (based on memory of past social situations) contaminates social interactions. High socially anxious volunteers participated in two conversations with another volunteer (conversational partner). During one conversation, the socially anxious volunteers held in mind a negative self-image, and during the other they held in mind a less negative (control) self-image. As predicted, when holding the negative image the socially anxious volunteers felt more anxious, reported using more safety behaviours, believed that they performed more poorly, and showed greater overestimation of how poorly they came across (relative to ratings by the conversational partner). Conversational partners rated the socially anxious volunteers' performance as poorer in the negative image condition. Furthermore, the conversation was contaminated since both groups of participants rated its quality as poorer in the negative image condition.     

Cultivating expertise in informal reasoning.

People generally develop some degree of competence in general informal reasoning and argument skills, but how do they go beyond this to attain higher expertise? Ericsson has proposed that high-level expertise in a variety of domains is cultivated through a specific type of practice, referred to as "deliberate practice." Applying this framework yields the empirical hypothesis that high-level expertise in informal reasoning is the outcome of extensive, deliberate practice. This paper reports results from two studies evaluating the hypothesis. University student participants completed 12 weeks of deliberate practice in informal reasoning. Quantity of practice was recorded by computer, and additionally assessed via self-report. The hypothesis was supported: Students in both studies showed a large improvement, and practice, as measured by computer, was related to amount of improvement in informal reasoning. These findings support adopting a deliberate practice approach when attempting to teach or learn expertise in informal reasoning.     

The I of the storm-relations between self and conscious emotion experience: comment on Lambie and Marcel (2002)

J. A. Lambie and A. J. Marcel (2002) outlined a framework for understanding varieties of conscious emotion experience. In their analysis, the self plays an important role in conscious emotion experience. In this critique, however, the authors propose that Lambie and Marcel's presentation of the self needs further specification if it is to account for varieties of conflicted emotional experience, particularly those characteristic of dissociative states. The authors propose that a more elaborated self-construct is necessary to account for these phenomena involving either the "splitting off of significant self-related concerns or the existence of multiple self-constructs. These arguments are illustrated by clinical and subclinical case examples.     

A recurrent connectionist model of group biases

Major biases and stereotypes in group judgments are reviewed and modeled from a recurrent connectionist perspective. These biases are in the areas of group impression formation (illusory correlation), group differentiation (accentuation), stereotype change (dispersed vs. concentrated distribution of inconsistent information), and group homogeneity. All these phenomena are illustrated with well-known experiments, and simulated with an autoassociative network architecture with linear activation update and delta learning algorithm for adjusting the connection weights. All the biases were successfully reproduced in the simulations. The discussion centers on how the particular simulation specifications compare with other models of group biases and how they may be used to develop novel hypotheses for testing the connectionist modeling approach and, more generally, for improving theorizing in the field of social biases and stereotype change.     

Underemployment in America: Measurement and Evidence

An important way in which employment hardship has come to be conceptualized and measured is as underemployment. Underemployment goes beyond mere unemployment (being out of a job and looking for work), to include those who have given up looking for work, part-time workers whose employer(s) cannot give them full-time work, and the working poor. To provide needed background for the other articles in this special issue, we trace the history of the concept of underemployment, review existing empirical literature, offer a critique of the measurement of underemployment as conventionally operationalized, and provide up-to-date evidence on the trends and correlates of underemployment in the United States.     

Inflated and contradictory category naming deficits in Alzheimer's disease?

Although some studies have documented category-specific deficits in patients with Alzheimer's disease, others have not. One possible reason is that where control groups have been used in previous studies, they have performed at ceiling; and this may spuriously affect the incidence and type of deficit reported (especially with common statistical techniques such as z-scores). We examined this issue in 18 Alzheimer's patients and 26 elderly controls, who named two picture sets: a simple set that typically produces ceiling effects (Set 1) and one that produces a normal distribution in controls (Set 2). Sets 1 and 2 produced inconsistent and even contradictory deficits in the same patients. The results also show that ceiling effects may inflate the number of living thing deficits and hence, distort the reported ratio of living to nonliving cases.