The effect of midazolam on implicit and explicit memory in category exemplar production and category cued recall

Transfer-appropriate processing theory (Roediger, Weldon, & Challis, 1989) proposes that dissociations between performance on explicit and implicit memory tests arise because these tests often rely on different types of information processing (e.g., perceptual processing vs conceptual processing). This perspective predicts that implicit and explicit memory tasks that rely primarily on conceptual processing should show comparable results, not dissociations. Numerous studies have demonstrated such similarities. It is, however, possible that these results arise from explicit memory contamination of performance on implicit memory tasks. To address this issue, an experiment was conducted in which participants were administered the sedative midazolam prior to study. Midazolam is known to create a temporary, but dense, period of anterograde amnesia. The effects of blocking stimulus materials by semantic category at study and generation at study were investigated on category exemplar production and category-cued recall. The results of this study demonstrated a dissociation of the effects of midazolam on category exemplar production and category-cued recall. Specifically, midazolam reduced the effect of blocking stimulus materials in category-cued recall, but not in category exemplar production. The differential effect of midazolam on explicit and implicit memory is at odds with transfer-appropriate processing theory and suggests that theories of memory must distinguish the roles of different types of conceptual processing on implicit and explicit memory tests.     

Visual skills in airport-security screening

Abstract— An experiment examined visual performance in a simulated luggage-screening task. Observers participated in five sessions of a task requiring them to search for knives hidden in x-ray images of cluttered bags. Sensitivity and response times improved reliably as a result of practice. Eye movement data revealed that sensitivity increases were produced entirely by changes in observers' ability to recognize target objects, and not by changes in the effectiveness of visual scanning. Moreover, recognition skills were in part stimulus-specific, such that performance was degraded by the introduction of unfamiliar target objects. Implications for screener training are discussed.     

Retrieval-induced forgetting occurs in tests of item recognition

Using the retrieval-practice paradigm (Anderson, R. A. Bjork, & E. L. Bjork, 1994), we tested whether or not retrieval-induced forgetting could be found in item recognition tests. In Experiment 1, retrieval practice on items from semantic categories depressed recognition of nonpracticed items from the same categories. Similar results were found in Experiment 2 in a more stringent source test for practiced, nonpracticed, and new items. These results conceptually replicate those of previous retrieval-induced forgetting studies done with cued recall (e.g., Anderson et al., 1994). Our findings are inconsistent with the hypothesis that item-specific cues during retrieval will eliminate retrieval interference in the retrieval-practice paradigm (Butler, Williams, Zacks, & Maki, 2001). We discuss our results in relation to other retrieval interference and inhibition effects in recall and recognition.     

Hebbian learning and development

Hebbian learning is a biologically plausible and ecologically valid learning mechanism. In Hebbian learning, 'units that fire together, wire together'. Such learning may occur at the neural level in terms of long-term potentiation (LTP) and long-term depression (LTD). Many features of Hebbian learning are relevant to developmental theorizing, including its self-organizing nature and its ability to extract statistical regularities from the environment. Hebbian learning mechanisms may also play an important role in critical periods during development, and in a number of other developmental phenomena.     

Organizational justice and stress: the mediating role of work-family conflict

This study examined the relationship between organizational justice and stress and whether work-family conflict was a mediator of the relationship. Distributive, procedural, interpersonal, and informational injustice were cast as stressors to explore their relationships with the stress levels of 174 faculty members employed at 23 U.S. universities. The results revealed that procedural and interpersonal justice had the strongest relationships with stress, and that these effects were mediated by work-family conflict. The presence of justice seemed to allow participants to better manage the interface of their work and family lives, which was associated with lower stress levels. These results were observed even when controlling for job satisfaction and the presence of organizational work-family policies.     

Relating distinctive orthographic and phonological processes to episodic memory performance

Three experiments examined the role of three distinctive perceptual factors in recognition and recall memory. Using a subject-paced presentation rate, the first two experiments (recognition and recall) examined (1) the number of phonological-to-orthographic neighbors, (2) phonological-to-orthographic consistency, and (3) orthographic-to-phonological consistency. The third experiment (recall) reexamined the number of phonological-to-orthographic neighbors, using an experimenter-paced presentation rate of 2 sec per item. In both recognition and recall memory tasks, the number of phonological-to-orthographic neighbors influenced memory performance, whereas the two types of consistency did not. The results indicate that having fewer phonological-to-orthographic neighbors (i.e., having distinct mappings between orthography and phonology, and between phonology and orthography, e.g., pulp) relieve words from interference in episodic memory tests for such words. Furthermore, words that are indistinct in terms of these mappings (e.g., tuck) are subject to interference from words with similar representations (e.g., luck, buck, stuck), and this weakens the memory trace for a particular word.     

Change in cognitive capabilities in the oldest old: the effects of proximity to death in genetically related individuals over a 6-year period

Change in cognitive abilities was assessed over a 6-year period in a sample of monozygotic and same-sex dizygotic twin pairs (N = 507 individuals), aged 80 and older (mean age = 83.3 years: SD = 3.1). who remained nondemented over the course of the study. Latent growth models (LGMs) show that chronological age and time to death are consistent predictors of decline in measures of memory, reasoning, speed, and verbal abilities. Multivariate LGM analysis resulted in weak and often negative correlations among rates of change between individuals within twin pairs, indicating greater differential change within twin pairs than occurs on average across twin pairs. These findings highlight several challenges for estimating genetic sources of variance in the context of compromised health and mortality-related change.     

On spatial response code activation in a Simon task

The Simon effect refers to the performance advantage for trials where the task-irrelevant location of a target spatially corresponds with the location of the response. It is thought that the irrelevant spatial code of the target facilitates responding by automatically pre-activating the spatially corresponding response code. This spatial code is thought to passively decay shortly after its activation. In this investigation, the response was selected according to the identity of a central cue. The selected response was executed or withheld depending the identity (Experiment 1) or the presence (Experiment 2) of the target. Varying the stimulus-onset asynchrony (SOA), between the central response cue and the peripheral target, allowed for a time-course analysis of the Simon effect. The results of two experiments provided no indication that the activation level of the irrelevant spatial code decayed while the relevant response was prepared. Although reaction times increased as the SOA decreased, the Simon effect was additive with SOA, suggesting that the automatic activation of the task-irrelevant spatial code was delayed until the task-relevant response code was mostly prepared, perhaps due to the capacity limitations of response selection.     

Integrating biological and social processes in relation to early-onset persistent aggression in boys and girls

This study examined the relationship between biological and social risk factors and aggressive behavior patterns in an Australian high-risk sample of 370 adolescents. Perinatal, temperamental, familial, sociodemographic, and behavioral data were collected during interviews completed during pregnancy. immediately postpartum, and when the children were 6 months old and 5, 14, and 15 years old. Youths were given tests of verbal and neuropsychological functioning at the age 5 and age 15 follow-ups. Youths were divided into early-onset persistent aggression, adolescent-onset aggression, and nonaggressive behavior groups. Results revealed that the interaction of biological and social risk factors was significantly related to early-onset persistent aggression. Gender and developmental phase of measurement moderated the relationship between biosocial risks and the outcomes of early-onset persistent aggression and adolescent-onset aggression.     

Conscientiousness, autonomy fit, and development: a longitudinal study

The authors examined employee development and its relationship with Conscientiousness and person-environment fit (in terms of needs and supplies of autonomy). They hypothesized that Conscientiousness would be positively associated with development but only when employees felt that the autonomy supplied by the organization did not fit their needs. In other words, whereas Conscientiousness could supply the dispositional resources for development, misfit was needed to create the need for development. The results supported the authors' predictions. Conscientiousness was positively related to development but only when employees were misfits with respect to autonomy. Employee involvement in development activities was then linked to subsequent fit.