Monitoring the capacity of working memory: Executive control and effects of listening effort

In two experiments, we used an interruption-and-recall (IAR) task to explore listeners’ ability to monitor the capacity of working memory as new information arrived in real time. In this task, listeners heard recorded word lists with instructions to interrupt the input at the maximum point that would still allow for perfect recall. Experiment 1 demonstrated that the most commonly selected segment size closely matched participants’ memory span, as measured in a baseline span test. Experiment 2 showed that reducing the sound level of presented word lists to a suprathreshold but effortful listening level disrupted the accuracy of matching selected segment sizes with participants’ memory spans. The results are discussed in terms of whether online capacity monitoring may be subsumed under other, already enumerated working memory executive functions (inhibition, set shifting, and memory updating).     

Moderators of the Dynamic Link Between Alcohol Use and Aggressive Behavior among Adolescent Males

Although longitudinal evidence has linked alcohol use with aggressive behavior during adolescence, most studies have failed to adequately control for the numerous between-individual differences that may underlie this association. In addition, few studies of adolescents have examined whether the nature of the within-individual association between alcohol use and aggression depends on individual and contextual factors. To address these limitations, this study examined the association between within-individual changes in alcohol use and aggressive behavior across adolescence and determined whether impulsive behavior, positive attitudes toward violence, violent peers, neighborhood crime, and race moderated this association. Data from 971 adolescent males assessed annually from ages 13 to 18 were analyzed using a within-individual regression panel model that eliminated all stable between-individual factors as potential confounds. Findings indicated that within-individual increases in alcohol use quantity from one’s own typical levels of drinking were concurrently associated with within-individual increases in aggressive behavior, and vice versa. However, increases in alcohol were more strongly linked to increases in aggressive behavior among boys with attitudes favoring violence and those who lived in high-crime neighborhoods. The association between alcohol and aggressive behavior was similar for White and Black young men. Interventions designed to reduce aggressive behaviors should consider targeting not only alcohol use, but also individual and environmental risk factors that contribute to this link.     

Attachment-Related Mentalization Moderates the Relationship Between Psychopathic Traits and Proactive Aggression in Adolescence

The lack of affective responsiveness to others’ mental states – one of the hallmarks of psychopathy – is thought to give rise to increased interpersonal aggression. Recent models of psychopathy highlight deficits in attachment security that may, in turn, impede the development of relating to others in terms of mental states (mentalization). Here, we aimed to assess whether mentalization linked to attachment relationships may serve as a moderator for the relationship between interpersonal aggression and psychopathic traits in an adolescent community sample. Data from 104 males and females with a mean age of 16.4 years were collected on mentalization capacities using the Reflective Functioning Scale on the Adult Attachment Interview (AAI). Psychopathic traits and aggressive behavior were measured via self-report. Deficits in mentalization were significantly associated with both psychopathic traits and proactive aggression. As predicted, mentalization played a moderating role, such that individuals with increased psychopathic tendencies did not display increased proactive aggression when they had higher mentalizing capacities. Effects of mentalization on reactive aggression were fully accounted for by its shared variance with proactive aggression. Psychopathic traits alone only partially explain aggression in adolescence. Mentalization may serve as a protective factor to prevent the emergence of proactive aggression in spite of psychopathic traits and may provide a crucial target for intervention.     

International–local remuneration differences across six countries: Do they undermine poverty reduction work?

Despite the rhetoric of a single global economy, professionals in poorer countries continue to be remunerated differently depending on whether they are compensated at a local vs. international rate. Project ADDUP (Are Development Discrepancies Undermining Performance?) surveyed 1290 expatriate and local professionals (response rate = 47%) from aid, education, government, and business sectors in (1) Island Nations (Papua New Guinea, Solomon Islands), (2) landlocked economies (Mala?i, Uganda), and (3) emerging economies (India, China). Difference in pay was estimated using purchasing power parity, from the World Bank's World Development Indicators 2007. Psychological measures included self‐reported pay and benefits (remuneration), self‐attributed ability, remuneration comparison, sense of justice in remuneration, remuneration‐related motivation, thoughts of turnover and thoughts about international mobility. We included control measures of candour, culture shock, cultural values (horizontal/vertical individualism/collectivism), personality (from the “big five”), job satisfaction and work engagement. Controlling for these and country (small effects) and organization effects (medium), (a) pay ratios between international and local workers exceeded what were perceived to be acceptable pay thresholds among respondents remunerated locally; who also reported a combination of a sense of relative (b) injustice and demotivation; which (c) together with job satisfaction/work engagement predicted turnover and international mobility. These findings question the wisdom of dual salary systems in general, expose and challenge a major contradiction between contemporary development policy and practice, and have a range of practical, organizational, and theoretical implications for poverty reduction work.     

Matching methods for selection of subjects for follow-up

This work examines ways to make the best use of limited resources when selecting individuals to follow up in a longitudinal study estimating causal effects. In the setting under consideration, covariate information is available for all individuals but outcomes have not yet been collected and may be expensive to gather, and thus only a subset of the comparison subjects will be followed. Expressions in Rubin and Thomas (1996, 2000) show the benefits that can be obtained, in terms of reduced bias and variance of the estimated treatment effect, of selecting comparison individuals well-matched to those in the treated group, as compared to a random sample of comparison individuals. We primarily consider non-experimental settings but also consider implications for randomized trials. The methods are illustrated using data from the Johns Hopkins University Baltimore Prevention Program, which included data collection from age 6 to young adulthood of participants in an evaluation of two early elementary-school based universal prevention programs.     

Ephemeral Mechanisms and Historical Explanation

While much of the recent literature on mechanisms has emphasized the superiority of mechanisms and mechanistic explanation over laws and nomological explanation, paradigmatic mechanisms—e.g., clocks or synapses—actually exhibit a great deal of stability in their behavior. And while mechanisms of this kind are certainly of great importance, there are many events that do not occur as a consequence of the operation of stable mechanisms. Events of natural and human history are often the consequence of causal processes that are ephemeral and capricious. In this paper I shall argue that, notwithstanding their ephemeral nature, these processes deserve to be called mechanisms. Ephemeral mechanisms share important characteristics with their more stable cousins, and these shared characteristics will help us to understand connections between scientific and historical explanation.