The role of probability of success estimates in the sunk cost effect

The sunk cost effect is manifested in a tendency to continue an endeavor once an investment has been made. Arkes and Blumer (1985) showed that a sunk cost increases one's estimated probability that the endeavor will succeed [p(s)]. Is this p(s) increase a cause of the sunk cost effect, a consequence of the effect, or both? In Experiment 1 participants read a scenario in which a sunk cost was or was not present. Half of each group read what the precise p(s) of the project would be, thereby discouraging p(s) inflation. Nevertheless these participants manifested the sunk cost effect, suggesting p(s) inflation is not necessary for the effect to occur. In Experiment 2 participants gave p(s) estimates before or after the investment decision. The latter group manifested higher p(s), suggesting that the inflated estimate is a consequence of the decision to invest. Copyright © 2000 John Wiley & Sons, Ltd.     

Enhanced encoding of the co-actor's target stimuli during a shared non-motor task

Task co-representation has been proposed to rely on the motor brain areas’ capacity to represent others’ action plans similarly to one's own. The joint memory (JM) effect suggests that working in parallel with others influences the depth of incidental encoding: Other-relevant items are better encoded than non-task-relevant items. Using this paradigm, we investigated whether task co-representation could also emerge for non-motor tasks. In Experiment 1, we found enhanced recall performance to stimuli relevant to the co-actor also when the participants’ task required non-motor responses (counting the target words) instead of key-presses. This suggests that the JM effect did not depend on simulating the co-actor's motor responses. In Experiment 2, direct visual access to the co-actor and his actions was found to be unnecessary to evoke the JM effect in case of the non-motor, but not in case of the motor task. Prior knowledge of the co-actor's target category is sufficient to evoke deeper incidental encoding. Overall, these findings indicate that the capacity of task co-representation extends beyond the realm of motor tasks: Simulating the other's motor actions is not necessary in this process.     

Do Life Course Transitions and Social Bonds Influence Male and Female Offending Differently? Gender Contrasts and Criminality

A longstanding issue facing criminologists is the challenge of developing theoretical models that provide comprehensive explanations of the onset and persistence of criminality among males and females. One promising perspective that has developed in recent years has been life course theory. Using data from the National Longitudinal Study of Adolescent Health, this research explores the question of whether the elements of social development shape the trajectory of persistent offending in a gender-neutral fashion, or are the dynamics shaping life course criminality unique for males and females. The results provide a number of useful insights into the relationship between gender, life course transition factors, and longitudinal patterns of criminality.     

Personality assessment in DSM-5: empirical support for rating severity, style, and traits

Despite a general consensus that dimensional models are superior to the categorical representations of personality disorders in DSM-IV, proposals for how to depict personality pathology dimensions vary substantially. One important question involves how to separate clinical severity from the style of expression through which personality pathology manifests. This study empirically distinguished stylistic elements of personality pathology symptoms from the overall severity of personality disorder in a large, longitudinally assessed clinical sample (N = 605). Data suggest that generalized severity is the most important single predictor of current and prospective dysfunction, but that stylistic elements also indicate specific areas of difficulty. Normative personality traits tend to relate to the general propensity for personality pathology, but not stylistic elements of personality disorders. Overall, findings support a three-stage diagnostic strategy involving a global rating of personality disorder severity, ratings of parsimonious and discriminant valid stylistic elements of personality disorder, and ratings of normative personality traits.     

The default mode network and altered consciousness in epilepsy

The default mode network has been hypothesized based on the observation that specific regions of the brain are consistently activated during the resting state and deactivated during engagement with task. The primary nodes of this network, which typically include the precuneus/posterior cingulate, the medial frontal and lateral parietal cortices, are thought to be involved in introspective and social cognitive functions. Interestingly, this same network has been shown to be selectively impaired during epileptic seizures associated with loss of consciousness. Using a wide range of neuroimaging and electrophysiological modalities, decreased activity in the default mode network has been confirmed during complex partial, generalized tonic-clonic, and absence seizures. In this review we will discuss these three seizure types and will focus on possible mechanisms by which decreased default mode network activity occurs. Although the specific mechanisms of onset and propagation differ considerably across these seizure types, we propose that the resulting loss of consciousness in all three types of seizures is due to active inhibition of subcortical arousal systems that normally maintain default mode network activity in the awake state. Further, we suggest that these findings support a general "network inhibition hypothesis", by which active inhibition of arousal systems by seizures in certain cortical regions leads to cortical deactivation in other cortical areas. This may represent a push-pull mechanism similar to that seen operating between cortical networks under normal conditions.     

Surrogate endpoints in suicide research

Surrogate endpoints frequently substitute for rare outcomes in research. The ability to learn about completed suicides by investigating more readily available and proximate outcomes, such as suicide attempts, has obvious appeal. However, concerns with surrogates from the statistical science perspective exist, and mounting evidence from psychometric, neurochemical, genetic, and neuroimaging studies suggests that surrogates may be particularly problematic in suicide research. The need for greater phenotypic refinement of suicide-related behaviors, development of and adherence to a shared suicide nomenclature, and conservative interpretation of investigational results that are limited to the precise population and suicide-related behavior under examination are discussed.