Acetylcholine and olfactory perceptual learning

Olfactory perceptual learning is a relatively long-term, learned increase in perceptual acuity, and has been described in both humans and animals. Data from recent electrophysiological studies have indicated that olfactory perceptual learning may be correlated with changes in odorant receptive fields of neurons in the olfactory bulb and piriform cortex. These changes include enhanced representation of the molecular features of familiar odors by mitral cells in the olfactory bulb, and synthetic coding of multiple coincident odorant features into odor objects by cortical neurons. In this paper, data are reviewed that show the critical role of acetylcholine (Ach) in olfactory system function and plasticity, and cholinergic modulation of olfactory perceptual learning at both the behavioral and cortical level.     

Making your next move: Dorsolateral prefrontal cortex and planning a sequence of actions in freely moving monkeys

Prefrontal damage disrupts planning, as measured by disorders of the activities of daily living (Humphreys & Forde, 1998; Shallice & Burgess, 1991). In a monkey model of this form of planning, a variant of the delayed alternation task was performed by freely moving monkeys. In a 16 x 16-ft. testing room, four feeders were located in the middle of each wall. In the north task, monkeys alternated between feeders: west-north-east-north-west, and so forth. In the south task, the alternation sequence was east-south-west-south-east, and so forth. Neuronal activity was recorded during walking along the eight paths, constituting the north and south tasks. To succeed, monkeys had to memorize the alternation rule and monitor both their place in the sequence and the previously made spatially directed action before deciding to walk to a new location to the left or right of the current location. Responsive dorsolateral prefrontal neurons are strikingly selective. Sustained neuronal activity reflects the spatial direction of an ongoing or upcoming response. It is important that such selective responses occur in one but not both tasks, even though the movements are exactly the same in both tasks and at each location. We suggest that selective neuronal activity is tuned through learning and reflects the fundamental units of a planning mechanism: Individual neurons encode specific components of a sequence of behavioral actions and their temporal order. Populations of such neurons represent all the steps necessary to perform the north and south tasks. The sustained activity of these neurons suggests that planning and working memory mechanisms are integrated.     

Active versus passive learning and testing in a complex outside built environment

A review of the evidence on active and passive learning in virtual environments (VEs) suggests that both conditions have shown superiority under some conditions of learning and testing, but there is no consistent outcome pattern. Measures of transfer between virtual and real environments have also revealed a variety of outcomes. Following either active or passive learning in a VE, experiment 1 assessed measures of orientation and distance estimation in that VE and in a real-world equivalent environment. On measures of direct and relative distance, more accurate estimates were found for active than passive VE explorers. A suggestion was also noted for the orientation estimates to benefit from real-world rather than VE testing. With an improvement to the procedure, experiment 2 found similar real versus virtual orientation judgements, suggesting that an opportunity for active learning during the test procedure probably influenced orientation measures in experiment 1. We conclude that the effects of interactivity are unreliable and vary with the measures used, and that testing in virtual and real environments leads to similar outcomes.     

Virtual visiting seminar replaces verbatim seminar in Clinical Pastoral Education (CPE)

The article addresses the question of the value of the virtual visiting seminar compared to the verbatim seminar in a Clinical Pastoral Education (CPE) Unit. A Virtual Visit occurs when a volunteer allows a CPE student to engage them in a pastoral visit with the expressed purpose of providing feedback to the student. The effectiveness of the virtual visiting seminar was monitored by a Site Review Team, two independent expert witnesses, by students who have experienced both learning tools, and the Education Sub Committee of the Pastoral Care Advisory Committee. The results point to advantages of the virtual visiting seminar over the verbatim seminar.     

Heightened subjective experience of depression in borderline personality disorder

Despite the frequent comorbidity of major depression and borderline personality disorder (BPD), limited research has examined what effect this comorbidity has on the severity, course, and presentation of depression. The purpose of this study was to examine whether the severity of major depressive disorder (MDD) in the context of comorbid borderline personality disorder (BPD) differs from MDD when comorbid BPD is not present and to determine whether different measures of depression yield convergent findings. Sixty patients diagnosed with DSM-IV MDD participated in this study. Twenty-nine were diagnosed with DSM-IV BPD, while the remaining 31 had no Axis II diagnosis. Depression was evaluated with both clinician (Hamilton Rating Scale for Depression) and self-report (Beck Depression Inventory) ratings. While the two groups were rated as similarly depressed by clinicians on the overall rating and the factor scores, the MDD/BPD group reported more severe depressive symptoms on the self-report measure. This difference was significant even after controlling for clinician-rated severity. Gender interacted with diagnosis, males in the BPD group showed the largest discrepancies between clinician ratings and self-reports. Posthoc analyses of HDRS factors with the BDI showed that the clinicianrated cognitive disturbance and retardation factors were correlated with self-rated severity overall. Within subgroups, only the retardation factor was correlated with the BDI. Our results suggest that while depressed individuals with and without BPD may be rated as similarly depressed when assessed with objective rating methods, the subjective experience of the depression may be rated as more intense or severe by patients with comorbid BPD. The mechanism underlying this effect remains unknown, and requires further research.     

Selective preference in visual fixation away from negative images in old age? An eye-tracking study

Recent studies have suggested that older individuals selectively forget negative information. However, findings on a positivity effect in the attention of older adults have been more mixed. In the current study, eye tracking was used to record visual fixation in nearly real-time to investigate whether older individuals show a positivity effect in their visual attention to emotional information. Young and old individuals (N = 64) viewed pairs of synthetic faces that included the same face in a nonemotional expression and in 1 of 4 emotional expressions (happiness, sadness, anger, or fear). Gaze patterns were recorded as individuals viewed the face pairs. Older adults showed an attentional preference toward happy faces and away from angry ones; the only preference shown by young adults was toward afraid faces. The age groups were not different in overall cognitive functioning, suggesting that these attentional differences are specific and motivated rather than due to general cognitive change with age.     

Are juvenile offenders extreme future discounters?

It has been the prevailing view that young offenders are more present oriented than their peers, but this view has little empirical basis other than the actions that have defined these youth as offenders. In the present study, we used a decision task with actual monetary consequences to assess the tendency of young offenders and a control group of high school students to discount the future. The young offenders were not significantly different from the students in discounting the future, even though the young offenders scored significantly higher on a sensation-seeking personality scale, were less likely to have lived with their fathers, and had changed schools more often. Young offenders and control participants were also similar in the extent to which they manifested a clear vision of the future by anticipating which future milestones would occur sooner, in a task pairing milestones with each other and with year markers.     

Stem cell research in a Catholic institution: yes or no?

Catholic teaching has no moral difficulties with research on stem cells derived from adult stem cells or fetal cord blood. The ethical problem comes with embryonic stem cells since their genesis involves the destruction of a human embryo. However, there seems to be significant promise of health benefits from such research. Although Catholic teaching does not permit any destruction of human embryos, the question remains whether researchers in a Catholic institution, or any researchers opposed to destruction of human embryos, could participate in research on cultured embryonic stem cells, or whether a Catholic institution could use any therapy that ultimately results from such research. This position paper examines how such research could be conducted legitimately in a Catholic institution by using an ethical analysis involving a narrative context, the nature of the moral act, and the principle of material cooperation, along with references to significant ethical assessments. It also offers tentative guidelines that could be used by a Catholic institution in implementing such research.     

Adolescents' psychological response to the experience of community interpersonal violence: a cross-national and a cross-cultural comparison

A comparative cross-national study investigating the level of experience with community interpersonal violence, level of psychological distress, and the relationship between exposure and distress among adolescents is presented. Participants were 617 first-year college students comprising African Americans and Jamaican Americans living in New York City, and Jamaicans living in Kingston, Jamaica. The three groups are similar in terms of age, gender, educational level, and race; they differ in location of residence, culture, and immigration status. Location of residence is related to exposure; immigration status is related to distress; but culture is not related to vulnerability when exposed. The effect size of the relationship between exposure and distress appears to be robust across variations in culture, amount of exposure, and level of distress.