Anterior temporal cortex and semantic memory: Reconciling findings from neuropsychology and functional imaging

Studies of semantic impairment arising from brain disease suggest that the anterior temporal lobes are critical for semantic abilities in humans; yet activation of these regions is rarely reported in functional imaging studies of healthy controls performing semantic tasks. Here, we combined neuropsychological and PE T functional imaging data to show that when healthy subjects identify concepts at a specific level, the regions activated correspond to the site of maximal atrophy in patients with relatively pure semantic impairment. The stimuli were color photographs of common animals or vehicles, and the task was category verification at specific (e.g., robin), intermediate (e.g., bird), or general (e.g., animal) levels. Specific, relative to general, categorization activated the antero-lateral temporal cortices bilaterally, despite matching of these experimental conditions for difficulty. Critically, in patients with atrophy in precisely these areas, the most pronounced deficit was in the retrieval of specific semantic information.     

The effect of target group size on risk judgments and comparative optimism: the more, the riskier

In 5 experiments, college students exhibited a group size effect on risk judgments. As the number of individuals in a target group increased, so did participants' judgments of the risk of the average member of the group for a variety of negative life events. This happened regardless of whether the stimuli consisted of photographs of real peers or stick-figure representations of peers. As a result, the degree to which participants exhibited comparative optimism (i.e., judged themselves to be at lower risk than their peers) also increased as the size of the comparison group increased. These results suggest that the typical comparative optimism effect reported so often in the literature might be, at least in part, a group size effect. Additional results include a group size effect on judgments of the likelihood that the average group member will experience positive and neutral events and a group size effect on perceptual judgments of the heights of stick figures. These latter results, in particular, support the existence of a simple, general cognitive mechanism that integrates stimulus numerosity into quantitative judgments about that stimulus.     

Health-Risking Social Behaviors: Moving Forward

The National Institute of Mental Health (NIMH) and the National Institute on Drug Abuse (NIDA) have a long history of supporting investigator-initiated research and research training to enhance the scientific understanding of and effective interventions for a range of problems associated with youth violence. New technologies are emerging and basic research has promise for increasing our understanding of how biological factors operate in conjunction with other factors to contribute to violent behavior, psychopathology, and drug abuse. This article describes emerging areas and directions for research in this important area of public health.The views expressed are those of the authors and do not necessarily represent those of the National Institute of Mental Health, the National Institute on Drug Abuse, the National Institutes of Health, the Department of Health and Human Services, or the U.S. Government.     

How two causes are different from one: The use of (un)conditional information in Simpson's paradox

In a causally complex world, two (or more) factors may simultaneously be potential causes of an effect. To evaluate the causal efficacy of a factor, the alternative factors must be controlled for (or conditionalized on). Subjects judged the causal strength of two potential causes of an effect that covaried with each other, thereby setting up a Simpson's paradox--a situation in which causal judgments should vary widely depending on whether or not they are conditionalized on the alternative potential cause. In Experiments 1 (table format) and 2 (trial-by-trial format), the subjects did conditionalize their judgments for one causal factor on a known alternative cause. The subjects also demonstrated that they knew what information was needed to properly make causal judgments when two potential causes are available. In Experiment 3 (trial-by-trial), those subjects who were not told about the causal mechanism by which the alternative cause operated were less likely to conditionalize on it. However, the more a subject recognized the covariation between the alternative cause and the effect, the more the subject conditionalized on it. Such behavior may arise from the interaction between bottom-up and top-down processing.     

Implicit /explicit memory versus analytic/nonanalytic processing: Rethinking the mere exposure effect

In studies of the mere exposure effect, rapid presentation of items can increase liking without accurate recognition. The effect on liking has been explained as a misattribution of fluency caused by prior presentation. However, fluency is also a source of feelings of familiarity. It is, therefore, surprising that prior experience can enhance liking without also causing familiarity-based recognition. We suggest that when study opportunities are minimal and test items are perceptually similar, people adopt an analytic approach, attempting to recognize distinctive features. That strategy fails because rapid presentation prevents effective encoding of such features; it also prevents people from experiencing fluency and a consequent feeling of familiarity. We suggest that the liking-without-recognition effect results from using an effective (nonanalytic) strategy in judging pleasantness, but an ineffective (analytic) strategy in recognition. Explanations of the mere exposure effect based on a distinction between implicit and explicit memory are unnecessary.     

Are false memories more difficult to forget than accurate memories? The effect of retention interval on recall and recognition

What is the effect of retention interval on accurate and false recollection in the Deese, Roediger, and McDermott (DRM) procedure? Previous research has suggested that false recall is more persistent than accurate recall, but the recognition results have been inconsistent. In two parametric studies, we tested recall and recognition for the same DRM lists, over retention intervals that ranged from no delay to a 2-month delay. We found that accurate and false memory were diminished by increases in retention interval, false memory persistence was present for recall and recognition, greater persistence for false memory than for accurate memory was more readily observed for recall than recognition, and the highthreshold (Pr), signal detection (d’), and nonparametric (A’) recognition measures differed in their sensitivity for detecting change. The effect of retention interval on accurate and false memory is consistent with expectations from fuzzy trace theory. In the DRM procedure, truth is not more memorable than fiction.     

Statistical inference for a linear function of medians: confidence intervals,hypothesis testing,and sample size requirements

When the distribution of the response variable is skewed, the population median may be a more meaningful measure of centrality than the population mean, and when the population distribution of the response variable has heavy tails, the sample median may be a more efficient estimator of centrality than the sample mean. The authors propose a confidence interval for a general linear function of population medians. Linear functions have many important special cases including pairwise comparisons, main effects, interaction effects, simple main effects, curvature, and slope. The confidence interval can be used to test 2-sided directional hypotheses and finite interval hypotheses. Sample size formulas are given for both interval estimation and hypothesis testing problems.     

Psychological assessment of adult survivors of childhood sexual abuse within a naturalistic clinical sample

This study investigates the long-term effects of childhood sexual abuse (CSA). Differences between abused and nonabused individuals in psychiatric symptomatology, interpersonal functioning, social and occupational functioning, personality dynamics, and therapeutic alliance were examined. The relationship between abuse severity and long-term effects was also analyzed. Data were gathered from 51 patients seeking individual psychotherapy at a community outpatient clinic. Findings suggested that CSA survivors tend to experience greater psychiatric distress and poorer interpersonal functioning than nonabused clinical controls. No significant differences were found in social and occupational functioning or in alliance developed by the end of the therapeutic assessment process. Abuse severity was significantly related to increased symptomatology and poorer interpersonal functioning. Findings support and extend existing literature and are especially useful for clinicians working with abuse survivors.     

Working Pasteur's Quadrant: harnessing science and action for community change

Community psychology in general and the field of prevention in particular has unquestioningly accepted the assumption that the research process should proceed in a linear fashion from a search for basic knowledge to application in the community context. This ignores the compelling insight offered by Stokes (1997) that the drive for new knowledge and the pursuit of application can be combined in a single effort. If research in community psychology pursues the drive for application without an equal commitment to the development of knowledge about underlying community processes of social cooperation and change, it will become a field less capable of innovative and enduring contributions to community well-being and effectiveness. Opportunities abound in community psychology for the simultaneous pursuit of new knowledge and more effective practice. We offer the example of a community leadership development program to promote collective efficacy as a case in point.     

Underemployment: Consequences for the Health and Well-Being of Workers

This paper addresses the question of how the adequacy of a person's employment status influences their health. We draw on and extend the Labor Utilization Framework to distinguish between different forms of underemployment (hours, income, skills, and status) and test their relative effects on a range of physical health and psychological well-being outcomes. Using data drawn from a nationally representative sample (N=1,429) of adults of working age, we assess the concurrent effects of underemployment through a longitudinal design that controls for prior levels of health and well-being. The results indicate that underemployed workers do report lower levels of health and well-being than adequately employed workers. However, the relationship varies by both types of underemployment and indicator of health and well-being. We conclude by discussing future research to explore the relationship between underemployment and health and well-being.