Striatal activity in concept learning

Striatal learning systems have been implicated in learning relationships between visual stimuli and outcomes. In the present study, the activity of the striatum during visual concept learning in humans was examined by using functional magnetic resonance imaging (fMRI). Participants performed three concept-learning tasks and a baseline task. The participants were trained to criterion before fMRI scanning on two tasks, verbal and implicit. In the verbal task, classification could be performed on the basis of a simple verbal rule, but in the implicit task, there was no simple verbal rule. The novel-implicit learning task, in which an implicit structure was used, was not encountered by the participants before scanning. Across all three concept-learning tasks, there was significant activation in the striatum, in comparison with the baseline task. The striatum was recruited similarly in classification when the participants had different levels of expertise (novel-implicit vs. verbal and implicit) and were able to verbalize their learning to different degrees (verbal vs. implicit and novel-implicit). There was left lateral occipital activation when learning was implicit (implicit and novel-implicit), but not when learning was easily verbalized (verbal).     

Visual and haptic perception of postural affordances in children and adults

The present study compared how children and adults perceived affordances for upright stance when information was available either visually or haptically. 12 adults (mean age=26.5 years) and 13 children (mean age=4.5 years) examined an adjustable wooden platform that was randomly set at five different degrees of inclination (17, 22, 27, 33, 39). In the haptic condition, a masking curtain excluded vision of the platform and the surface was explored with a hand-held, wooden dowel. Results showed that for both children and adults there was closer agreement between perceptual judgments and action capabilities in the visual condition. Children overestimated their ability to stand on the steeper slopes, took equal amounts of time to make their judgments across all slopes, and were equally confident in their judgments across all slopes. In contrast, adults were more accurate than children at judging the affordances for upright stance, took longer to respond close to the actual action boundary, and were less confident close to the action boundary. Furthermore, adults took longer to respond and were less confident in the haptic condition whereas children had similar response times and were equally confident in both conditions. These important differences between adults and children in the perception of a basic affordance are discussed with reference to the coupling between perception and action at different phases of the lifespan and to the factors that might influence the organization of this coupling. Finally, implications are drawn for the prevention of accidents and the promotion of basic motor competence in children.     

A further investigation of category learning by inference

Categories are learned in many ways besides by classification, for example, by making inferences about classified items. One hypothesis is that classifications lead to the learning of features that distinguish categories, whereas inferences promote the learning of the internal structure of categories, such as the typical features. Experiment 1 included single-feature and full-feature classification tests following either classification or inference learning. Consistent with predictions, inference learners did better on the single tests but worse on the full tests. Experiment 2 further showed that inference learners, unlike classification learners, were no better at classifying items that they had seen at study compared with equally typical items they had not seen at study. Experiment 3 showed that features queried about during inference learning were classified better than ones not queried about, although even the latter features showed some learning on single-feature tests. The discussion focuses on how different types of category learning lead to different category representations.     

Disaster mental health services following the 1995 Oklahoma City bombing: modifying approaches to address terrorism

How did the 1995 Oklahoma City bombing differ from prior disasters and what implications did it have for disaster mental health services and service delivery? The federal disaster mental health approach in this country developed largely out of experiences with natural disasters. The 1995 Oklahoma City bombing differed in several important ways, including the large number of human casualties, higher rates of psychopathology, and an extended period of concern due to the criminal investigation and trials, which suggested the need to consider modifications in the program. Outreach was extensive, but psychiatric morbidity of direct victims was greater than that of victims of natural disasters, emphasizing the need for attention to the triage and referral process. Other concerns that warrant consideration include practices related to record keeping and program evaluation.     

A laser-based eye-tracking system

This paper reports on the development of a new eye-tracking system for noninvasive recording of eye movements. The eye tracker uses a flying-spot laser to selectivelyimage landmarks on the eye and, subsequently, measure horizontal, vertical, and torsional eye movements. Considerable work was required to overcome the adverse effects of specular reflection of the flying-spot from the surface of the eye onto the sensing elements of the eye tracker. These effects have been largely overcome, and the eye-tracker has been used to document eye movement abnormalities, such as abnormal torsional pulsion of saccades, in the clinical setting.     

Pastoral counseling as an echoing process: a transformative therapy hour

The author posits that the essential core of pastoral counseling is an echoing process between client and therapist and between diagnostic listening and restorative responding. He illustrates this process by drawing on the case of a depressed middle-aged client. The therapist's response is described as conveyed through personal presence that is welcoming, participative, courageous, and responsive.     

Does Legalized Gambling Elevate the Risk of Suicide? An Analysis of U.S. Counties and Metropolitan Areas

This study addresses a possible link between suicide and casino gambling. Resident suicide rates are analyzed for (a) a 1990 cross-section of 148 U.S. metropolitan areas and (b) before and after the advent of legalized casinos in five U.S. counties. Data are drawn from government and gaming industry sources. In cross-section, metro area suicide is strongly correlated with region, accidental death and homicide rates, age and race composition, and economic vitality, followed by a modest net positive correlation with casino presence. By contrast, the time series analysis yields no evidence of a gambling effect.     

Not well known, used little and needed: Canadian chaplains' experiences of published spiritual assessment tools

What are Canadian chaplains' experiences of published assessment tools? Utilizing a quantitative and qualitative methodology with multiple investigators and theoretical triangulation, this article reports the results of a survey of chaplains in the Canadian Association for Pastoral Practice and Education (CAPPE) and interview results of 15 chaplains in three focus groups. Findings indicated that published spiritual assessment tools are not well know, used little, criticized for being reductionistic and not fitting the clinical situation. Participants noted, however, that spiritual assessment is needed for spiritual care. Thirty percent reported the development of their own tools (not published) and three published tools were mentioned by 50% and more. Discussion, limitations of the research, and suggestions for education, practice, and future research are offered.     

Neural correlates of evaluation associated with promotion and prevention regulatory focus

Higgins (1997, 1998) proposed two self-regulatory or motivational systems—one sensitive to gains (promotion) and one sensitive to losses (prevention). To examine the interaction of motivation and cognition, participants made good/bad or abstract/concrete judgments about concepts during fMRI scanning. After scanning, participants rated the extent to which each stimulus was good and bad and completed a questionnaire that measured promotion/prevention orientation. For each participant, contrast maps were generated representing the association between neural processing and stimulus valence (good/bad), and these factors were then regressed against participants’ promotion and prevention focus scores. For the good/bad but not for the abstract/concrete task, promotion focus was associated with greater activity in the amygdala, anterior cingulate, and extrastriate cortex for positive stimuli, and prevention focus was associated with activity in the same regions for negative stimuli; these results are consistent with the hypothesis that the way in which evaluative information is processed is influenced by individual differences in self-regulatory focus.     

The power law as an emergent property

Recent work has shown that the power function, a ubiquitous characteristic of learning, memory, and sensation, can emerge from the arithmetic averaging of exponential curves. In the present study, the forgetting process was simulated via computer to determine whether power curves can result from the averaging of other types of component curves. Each of several simulations contained 100 memory traces that were made to decay at different rates. The resulting component curves were then arithmetically averaged to produce an aggregate curve for each simulation. The simulations varied with respect to the forms of the component curves: exponential, range-limited linear, range-limited logarithmic, or power. The goodness of the aggregate curve's fit to a power function relative to other functions increased as the amount of intercomponent slope variability increased, irrespective of component-curve type. Thus, the power law's ubiquity may reflect the pervasiveness of slope variability across component functions. Moreover, power-curve emergence may constitute a methodological artifact, an explanatory construct, or both, depending on the locus of the effect.