The role of explicit and implicit learning processes in concept discovery

Analysis of individual learning curves and concurrent verbal protocols from three experiments concerning discovery of a non-salient verbal concept and a pictorial analogue (Chinese ideograph) of the concept show that a substantial transition phase occurs in which discrimination of exemplars from non-exemplars of the concept is above chance but not yet asymptotic. Under most conditions the ability to verbalize knowledge of the concept occurred almost simultaneously with the onset of the transition phase. However, the addition of noise in the form of false feedback (Experiment 3) created a temporary dissociation between task performance and verbalizable knowledge. Additional results suggest that individual hypothesis revision/rejection strategies affect the length of the transition phase of learning, whereas the size of the domain of hypotheses being sampled affects the number of trial blocks before the transition phase begins. The effect of feedback error on the relation between early rates of hypothesis generation and subsequent transition phase length also suggests that a strategy of quick rejection of falsified hypotheses becomes less adaptive in noisy task environments (e.g. when there are many exceptions to a rule or the concept is probabilistic). Finally, failure to find effects of variables known to affect implicit learning suggests that implicit learning processes do not play a large role in the discovery of this type of concept.     

Spirituality and Religiousness Among American Jews

In this article we examine the association between spirituality and religiousness for Jews in the United States. Using data from the most recent National Jewish Population Survey of 2000–2001, a large national sample, we examined the extent to which these two concepts correlate. In addition, we compared the relative importance of sociodemographic factors, stressors, and Jewish contextual factors in predicting spirituality and religiousness. We found that spirituality and religiousness correlated, but modestly; some variables were predictive of both concepts (less education, younger age, experienced anti-Semitism in last year, ethnic identity, social identity), some of being highly spiritual only (female, not living in the Northeast), and others of being highly religious only (being married, having a child at home, living in the Northeast, not living in the West, and Jewish background). The differences in sociodemographic characteristics and Jewish background suggest that family life (marriage, having children at home), knowledge about Judaism, and living in a geographic area where there is a high population of Jews are conducive to religiousness as a framework for meaning. Jewish contextual factors were salient for both spiritual and religious pathways.     

Effect of the 5-HTTLPR polymorphism on posttraumatic stress disorder,depression, anxiety,and quality of life among Iraq and Afghanistan veterans

Background and Objectives: Posttraumatic stress disorder (PTSD), depression, anxiety, and stress are significant problems among returning veterans and are associated with reduced quality of life. Design: A correlational design was used to examine the impact of a polymorphism (5-HTTLPR) in the serotonin transporter promoter gene on post-deployment adjustment among returning veterans. Methods: A total of 186 returning Iraq and Afghanistan veterans were genotyped for the 5-HTTLPR polymorphism. Symptoms of PTSD, depression, general stress, and anxiety were assessed along with quality of life. Results: After controlling for combat exposure, age, sex of the participant, and race, 5-HTTLPR had a significant multivariate effect on post-deployment adjustment, such that S′ carriers reported more post-deployment adjustment problems and worse quality of life than veterans homozygous for the L′ allele. This effect was larger when the analyses were restricted to veterans of European ancestry. Conclusions: Our findings suggest that veterans who carry the S′ allele of the 5-HTTLPR polymorphism may be at increased risk for adjustment problems and reduced quality of life following deployments to war zones.     

Time course of planning for object and action parameters in visually guided manipulation

Under visual guidance, subjects reached for and manipulated an object that variedin weight and surface texture (slipperiness). The manipulatory action was either grasping, lifting, or posting in a slot. The task was constrained or unconstrained with respect to speed, grasp pattern, and contact force. Initiation time (pre-reach), movement time (reach), and post-contact errors were measured, to examine planning for task performance at three points in time. Results indicate that in the constrained task, the manipulatory action was planned during the initiation time, but planning for object parameters was deferred until the reach interval. With relaxed task constraints, initiation times increased,and texture and manipulatory action had independent effects on premovement planning. Errors were affected interactively by all variables. The results suggest a planning process that unfolds over time, incorporating in turn the manipulatory action, object texture, and object weight. This unfolding accommodates variables proximate to the time where they will affect physical action.     

Infants discriminate manners and paths in non-linguistic dynamic events

Do 14- to 17-month-olds notice the paths and manners of motion events? English- and Spanish-learning infants were habituated to an animated motion event including a manner (e.g., spinning) and a path (e.g., over). They were then tested on four types of events that changed either the manner, the path, both, or neither component. Both English- and Spanish-learning infants attended to changes of manner and changes of path. Thus, infants from two different language communities proved sensitive to components of events that undergird relational term learning.     

Orientation illusions vary in size and direction as a function of task-dependent attention

Adding an upright inner square frame to an outer tilted square frame causes a central rod's perceived orientation to be directionally opposite the usual rod-and-frame illusion (RFI). Zoccolotti, Antonucci, Daini, Martelli, and Spinelli (1997) attributed this double RFI (DRFI) to Rock's (1990) hierarchical organization principle. In Experiment 1, this explanation predicted results for small (11 degrees ) but not larger (22 degrees and 33 degrees ) outer frame orientations. In two experiments with the DRFI, bottom-up, goal-driven attention was varied and direct and indirect measures of the framework's influence were compared. In Experiment 2, the RFI angular function was compared with two other DRFI conditions: a direct measure of perceived rod orientation and an indirect measure of the inner frame. These conditions induced directionally opposite effects. In Experiment 3, direct and indirect measures of the inner frame's perceived tilt were compared. Angular functions differing in size and direction were obtained. Experiment 4 replicated the previous results, using a different psychophysical procedure. All the results were consistent with the hierarchical organization mechanism but suggested different processing strategies due to different attentional weights. They were also consistent with other recent findings based on the Bayesian approach to accounts of illusory phenomena (e.g., Jazayeri & Movshon, 2006, 2007; Weiss, Simoncelli, & Adelson, 2002).     

Theory‐Based Determinants of Youth Smoking: A Multiple Influence Approach1

This study tested a broad array of determinants of smoking grounded in general social psychological theories, as well as personality and social development theories. Using data from 2,004 middle school students, all proximal and distal determinants significantly predicted smoking in the hypothesized direction. Further, hierarchical logistic regressions showed that intention to smoke, positive and negative attitudes toward smoking, impediments to smoking, self‐efficacy to resist smoking, parent norms, and academic success most strongly predicted current smoking. Hierarchical linear regressions suggested that parental relatedness, maladaptive coping strategies, depression, and low academic aspirations most strongly predicted susceptibility to smoking for those who had not yet smoked a cigarette. Global expectancies were the strongest predictor of susceptibility in low socioeconomic status students. These findings may guide the development of future theory‐based interventions that produce the greatest reductions in youth smoking.     

Service in the Gulf War and Significant Health Problems: Focus on the Central Nervous System

The consensus of several studies on health among Gulf War (GW)-deployed veterans is that they have elevated symptom complaints. Central nervous system (CNS) symptoms among these veterans have been assessed in several investigations. Studies have disagreed as to whether there are neuropsychological deficits in GW-deployed veterans relative to controls. When differences between these groups have been found, they have often been attributed to stress or psychiatric factors, although exposures to neurotoxic substances present in the GW theatre have also been indicted as possible explanations. A review of the existing literature as well as the 5 papers contained in this issue of Journal of Psychopathology and Behavioral Assessment suggests that the neuropsychological and health symptom sequelae of GW zone service are multidetermined and cannot easily be explained on the basis of simplistic models of causation. Psychological, historical, and exposure parameters must be considered in the scientific evaluation of this problem.