Detection of back random responding: effectiveness of MMPI-2 and Personality Assessment Inventory validity indices

Two experiments examined the detection and effects of back random responding (BRR) on the Minnesota Multiphasic Personality Inventory--2 (MMPI-2) and the Personality Assessment Inventory (PAI). Experiment 1 revealed that MMPI-2 Clinical and Content scales were relatively resistant to the effects of BRR. Fb--F > or = 20T was the most effective index for identifying invalid protocols. Experiment 2 revealed greater susceptibility of the PAI interpretive scales to the effects of BRR and less successful detection of BRR. The most effective PAI validity index was the combined indicator, ICN > or = 73T or INF > or = 75T. Clinical and empirical implications of these findings are discussed, and tentative modifications to the MMPI-2 interpretative guidelines are provided.     

Executive and visuospatial sketchpad resources in euthymic bipolar disorder: Implications for visuospatial working memory architecture

Visuospatial working memory theory is used to interpret the cognitive impairment in euthymic bipolar disorder. Such patients show deficits in the Corsi Blocks Test (CBT) and executive control. To understand these deficits, 20 euthymic bipolar patients and controls were administered the CBT, Visual Patterns Test (VPT), and a new visual memory task designed to make minimal demands on executive resources. Initial analyses validated the visual memory task and implicated executive involvement in the CBT and VPT. Subsequent analyses on a number of tests confirmed CBT and executive deficits while performance was normal on the VPT and visual memory test. ANCOVA indicated that impaired executive function underpinned patients' CBT performance. Implications for the interface between executive and slave systems of working memory are discussed.     

Stress effects in the hippocampus: synaptic plasticity and memory

It is now well-documented that exposures to uncontrollable (inescapable and unpredictable) stress in adulthood can have profound effects on brain and behavior. Converging lines of evidence from human and animal studies indicate that stress interferes with subsequent performances on a variety of hippocampal-dependent memory tasks. Animal studies further revealed that stress impedes ensuing induction of long-term potentiation (LTP) in the hippocampus. Because the hippocampus is important for key aspects of memory formation and because LTP has qualities congruent to an information storage mechanism, it is hypothesized that stress-induced modifications in hippocampal plasticity contribute to memory impairments associated with stress. Recent studies provide evidence that the amygdala, a structure important in stress- and emotion-related behaviors, plays a necessary role in the emergence of stress-associated changes in hippocampal LTP and memory. Early life stress also alters hippocampal plasticity and memory in a manner largely consistent with effects of adult stress exposure. This review focuses on endocrine-system-level mechanisms of stress effects in the hippocampus, and how stress, by altering the property of hippocampal plasticity, can subsequently influence hippocampal memory.     

Likelihood judgment based on previously observed outcomes: the alternative-outcomes effect in a learning paradigm

Previous research has demonstrated that intuitive perceptions of certainty regarding a focal outcome are sensitive to variations in how evidence supporting nonfocal alternatives is distributed, even when such variations have no bearing on objective probability. We investigated this alternative-outcomes effect in a learning paradigm in which participants made likelihood judgments on the basis of their memory for past observations of relevant outcomes. In Experiment 1, a manipulation of evidence (observed frequencies) across alternative outcomes influenced not only intuitive certainty estimates about a focal outcome but also numeric subjective probabilities. Experiment 2 ruled out the possibility that these effects were attributable to the influence of information loss on frequency estimations. The findings were consistent with the heuristic comparison account, which suggests that the judged likelihood of a focal outcome will be disproportionately influenced by the strength (frequency) of the strongest alternative outcome.     

Do domestic dogs show any evidence of being able to count?

Numerical competence has been demonstrated in a wide range of animal species. The level of numerical abilities shown ranges from simple relative numerousness judgements to true counting. In this study we used the preferential looking technique to test whether 11 pet dogs could count. The dogs were presented with three simple calculations: "1+1=2"; "1+1=1"; and "1+1=3". These calculations were performed by presenting the dogs with treats that were placed behind a screen that allowed manipulation of the outcome of the calculation. When the dogs expected the outcome they spent the same amount of time looking at the result of the calculation as they did on the initial presentation. However, when the result was unexpected dogs spent significantly longer looking at the outcome of the calculation. The results suggest that the dogs were anticipating the outcome of the calculations they observed, thus suggesting that dogs may have a rudimentary ability to count. Electronic Publication     

About the Contributors

Biography

About the Contributors     

Internal poverty and teen pregnancy

The subjects for the present study were drawn from the female students who participated in the National Education Longitudinal Study (NELS) initial eighth-grade data collection. Adolescent females who later became pregnant were matched on race, birth month, and birth year with adolescent females who did not report a pregnancy. The study examined selected predictor variables from the baseline 1988 wave of data in relation to the outcome variable of pregnancy status. Results indicated a statistically significant difference in locus of control between those females who later became pregnant and those who later did not experience a pregnancy during adolescence. Those who later became pregnant were much more likely to have an external locus of control (p = .0001). Females who later became pregnant were also more likely to have a poorer sense of personal efficacy (p = .0001). Finally, females who later experienced a teen pregnancy had more traditional occupational expectations (p = .006) and lower educational expectations (p = .001) than did those who did not later report a teen pregnancy.