The neuropsychology of ventral prefrontal cortex: decision-making and reversal learning

Converging evidence from human lesion, animal lesion, and human functional neuroimaging studies implicates overlapping neural circuitry in ventral prefrontal cortex in decision-making and reversal learning. The ascending 5-HT and dopamine neurotransmitter systems have a modulatory role in both processes. There is accumulating evidence that measures of decision-making and reversal learning may be useful as functional markers of ventral prefrontal cortex integrity in psychiatric and neurological disorders. Whilst existing measures of decision-making may have superior sensitivity, reversal learning may offer superior selectivity, particularly within prefrontal cortex. Effective decision-making on existing measures requires the ability to adapt behaviour on the basis of changes in emotional significance, and this may underlie the shared neural circuitry with reversal learning.     

How language acquisition builds on cognitive development

When children acquire a first language, they build on what they know--conceptual information that discriminates and helps create categories for the objects, relations and events they experience. This provides the starting point for language from the age of 12 months on. So children first set up conceptual representations, then add linguistic representations for talking about experience. Do they then discard earlier conceptual representations in favour of linguistic ones, or do they retain them? Recent research on the coping strategies that young children (and adults) rely on when they are unable to draw on language suggest that they retain both types of representations for use as needed.     

The DIAGNOSER project: Combining assessment and learning

DIAGNOSER is an Internet-based tool for classroom instruction. It delivers continuous formative assessment and feedback to high school physics students and their teachers about the correct and incorrect concepts and ideas the students may hold regarding physical situations. That is, it diagnoses misconceptions that underlie wrong answers of students, such as a confusion of velocity with acceleration. We use data about patterns of student responses, particularly consistency of errors from question to question, to improve the system’s understanding of student concepts.     

Medical burden, cerebrovascular disease, and cognitive impairment in geriatric depression: modeling the relationships with the CART analysis

Herein, the background information reflecting roles of medical burden, cerebrovascular disease and risk factors, and cognitive impairment in geriatric depression are reviewed. The authors then propose a nonparametric statistical approach to the data analysis of multiple putative causal variables for late-life depression, the Classification and Regression Tree Analysis. This analysis presents a useful approach to modeling nonlinear relationships and interactions among variables measuring physical and mental health, as well as magnetic resonance imaging and cognitive measures in depressed elderly. This method uncovers the existing interactions among multiple predictor variables, and provide thresholds for each variable, at which its predictive power becomes statistically significant. It presents a "hierarchy" of the predictors in a form of a decision tree by finding the best combination of predictors of an outcome. The authors present two models based on demographic variables, measures of vascular and nonvascular medical burden, neuroimaging indices, the Mini-Mental State Examination score, and neuropsychological test scores of 81 elderly depressed subjects. Cognitive tests of verbal fluency and executive function are identified as the best predictors of depression, followed by the frontal lobe volume and Mini-Mental State Examination. The authors observed that an interaction between frontal lobe volume, total lesion volume, and medical burden was predictive of depression.     

Female laryngectomees' satisfaction with communication methods and speech-language pathology services

132 female laryngectomees responded to a questionnaire regarding satisfaction with their communication methods as postlaryngectomees and speech-language pathology services. Respondents were satisfied overall with their primary communication selection; however, most would like to try a method that produced a more feminine-sounding voice. 68% were satisfied with their speech-language pathology services.     

Why do pitched horizontal lines have such a small effect on visually perceived eye level?

In two experiments, visually perceived eye level (VPEL) was measured while subjects viewed two-dimensional displays that were either upright or pitched 20 degrees top-toward or 20 degrees top-away from them. In Experiment 1, it was demonstrated that binocular exposure to a pair of pitched vertical lines or to a pitched random dot pattern caused a substantial upward VPEL shift for the top-toward pitched array and a similarly large downward shift for the top-away array. On the other hand, the same pitches of a pair of horizontal lines (viewed binocularly or monocularly) produced much smaller VPEL shifts. Because the perceived pitch of the pitched horizontal line display was nearly the same as the perceived pitch of the pitched vertical line and dot array, the relatively small influence of pitched horizontal lines on VPEL cannot be attributed simply to an underestimation of their pitch. In Experiment 2, the effects of pitched vertical lines, dots, and horizontal lines on VPEL were again measured, together with their effects on resting gaze direction (in the vertical dimension). As in Experiment 1, vertical lines and dots caused much larger VPEL shifts than did horizontal lines. The effects of the displays on resting gaze direction were highly similar to their effects on VPEL. These results are consistent with the hypothesis that VPEL shifts caused by pitched visual arrays are due to the direct influence of these arrays on the oculomotor system and are not mediated by perceived pitch.     

Social anxiety and self-impression: cognitive preparation enhances the beneficial effects of video feedback following a stressful social task

Negative and distorted images of the observable self are important in the development and maintenance of social phobia. Previous research has shown that video feedback has potential to correct the distorted self-perception [Rapee, R. M. & Hayman, K. (1996). The effects of video feedback on the self-evaluation of performance in socially anxious subjects. Behaviour Research and Therapy, 34, 315–322]. The present experiment investigated whether the construction of a self-image prior to viewing the video may enhance the therapeutic effects of video feedback. High and low socially anxious individuals gave a speech and then viewed the video of their performance. Half of the sample were given cognitive preparation prior to viewing the video. Cognitive preparation involved asking participants to (1) predict in detail what they will see in the video, (2) form an image of themselves giving the speech and (3) watch the video as though they were watching a stranger. Participants who received cognitive preparation prior to the video feedback made higher ratings of their overall performance and of specific aspects of their performance compared to those who were not given cognitive preparation and compared to the same ratings made prior to the video feedback. These results suggest that the therapeutic effects of video feedback can be enhanced by careful cognitive preparation which maximises the perceived discrepancy between self and video images.     

Child resiliency in inner-city families affected by HIV: the role of family variables

This study examined the role of family variables in child resiliency within a sample of African-American, inner-city children whose mothers are HIV-infected. Variables from three dimensions of the family were included: family structural variables, maternal variables, and mother-child (parenting) variables. The participants were 82 children between the ages of 6 and 11 and their HIV-infected mothers. Correlational analyses indicated that resiliency was associated only with three parenting variables: parent-child relationship, parental monitoring, and parental structure in the home. Hierarchical regression analyses indicated a multiplicative relationship between parental monitoring and parent-child relationship and between parental monitoring and parental structure in the home, suggesting that parenting variables potentiate each other. Clinical implications of the findings are considered.