Contrast polarity preservation's role in perception: explained and unexplained stimuli

Roncato and Casco (2003, Perception & psychophysics 65 1252-1272) had shown that in situations where the Gestalt principle of good continuity is put into conflict with preservation of contrast polarity (CP) the perception that preserves CP prevails. Parlangeli and Roncato (2010, Perception 39 255-259) have studied this question of preservation of CP more closely and have added an addendum to the rule. They have used stimuli consisting of a checkerboard of perpendicularly arranged rectangular bricks (white, gray, or black) and draughtsmen white, gray, or black disks placed at the corners of the bricks. This study has caused them to add an addendum to the rule of CP-preserved path-conjunction binding: if there are two contour completions that preserve the CP, the one with the higher contrast will prevail. Parlangeli and Roncato find that, for certain shades of the disks and bricks, the perpendicular lines of the checkerboard appear strikingly to be slanted or undulating. Here we consider all possible arrangements of relative magnitudes of checkerboards consisting of bricks of two different shades and disks of two shades as well, as such arrangements with widely varying differences in the magnitude of brightness. We have found a number of cases where the perception is not explained by the rule and addendum of Roncato and Casco, and Parlangeli and Roncato, and a case where preservation of "distant" as well as local CP plays a role in perception. The previously known cases, and the new exceptional unexplained stimuli we have found, warrant further study.     

Vision-fair neuropsychological assessment in normal aging, Parkinson's disease and Alzheimer's disease

We examined performance of healthy older and younger adults and individuals with Alzheimer's disease (AD) and Parkinson's disease (PD) on digit cancellation, a task putatively sensitive to cognitive impairment, but possibly affected by visual impairment, particularly in contrast sensitivity. Critical contrast thresholds were established to create custom stimulus arrays that were proximally matched across individuals. Age- and PD-related differences in search were fully accounted for by the sensory deficit. Increased contrast benefited AD patients, but could not override cognitive impairment. We conclude that visually fair neuropsychological testing can effectively compensate for normal age- and PD-related visual changes that affect cognitive performance. (PsycINFO Database Record (c) 2012 APA, all rights reserved).     

Genetic Counseling and the Ethical Issues Around Direct to Consumer Genetic Testing

Over the last several years, direct to consumer(DTC) genetic testing has received increasing attention in the public, healthcare and academic realms. DTC genetic testing companies face considerable criticism and scepticism,particularly from the medical and genetic counseling community. This raises the question of what specific aspects of DTC genetic testing provoke concerns, and conversely,promises, for genetic counselors. This paper addresses this question by exploring DTC genetic testing through an ethic allens. By considering the fundamental ethical approaches influencing genetic counseling (the ethic of care and principle-based ethics) we highlight the specific ethical concerns raised by DTC genetic testing companies. Ultimately,when considering the ethics of DTC testing in a genetic counseling context, we should think of it as a balancing act. We need careful and detailed consideration of the risks and troubling aspects of such testing, as well as the potentially beneficial direct and indirect impacts of the increased availability of DTC genetic testing. As a result it is essential that genetic counselors stay informed and involved in the ongoing debate about DTC genetic testing and DTC companies. Doing so will ensure that the ethical theories and principles fundamental to the profession of genetic counseling are promoted not just in traditional counseling sessions,but also on a broader level. Ultimately this will help ensure that the public enjoys the benefits of an increasingly genetic based healthcare system.     

Counseling Adolescents and the Challenges for Genetic Counselors

Genetic counselors may have an important role in helping the adolescent make an informed decision with regard to genetic testing and in helping them to adjust to genetic risk information. However, counseling techniques that are used with adults may not be always be suited to the adolescent population. Adolescence is a time of development during which separation from the family and formation of identity is achieved. The process of this development may impact the genetic counseling relationship. Family relationships may have a strong influence on the client's decision to have genetic testing. Additionally, it may be difficult to engage the client as adolescents may not have the ability to think abstractly and consider the short and long term consequences of genetic testing. It is helpful therefore to discuss the counseling process and techniques that may be useful when counseling these clients. This paper presents two case studies that illustrate some of the difficulties that may occur when counseling adolescents for genetic testing. The authors' have reflected on their clinical experience with these clients and this is presented here to add to the growing literature on this subject.     

Bingo! Externally supported performance intervention for deficient visual search in normal aging, Parkinson's disease, and Alzheimer's disease

External support may improve task performance regardless of an individual's ability to compensate for cognitive deficits through internally generated mechanisms. We investigated if performance of a complex, familiar visual search task (the game of bingo) could be enhanced in groups with suboptimal vision by providing external support through manipulation of task stimuli. Participants were 19 younger adults, 14 individuals with probable Alzheimer's disease (AD), 13 AD-matched healthy adults, 17 non-demented individuals with Parkinson's disease (PD), and 20 PD-matched healthy adults. We varied stimulus contrast, size, and visual complexity during game play. The externally supported performance interventions of increased stimulus size and decreased complexity resulted in improvements in performance by all groups. AD also obtained benefit from increasing contrast, presumably by compensating for their contrast sensitivity deficit. The general finding of improved performance across healthy and afflicted groups suggests the value of visual support as an easy-to-apply intervention to enhance cognitive performance.     

Sleep problems,anxiety and cognitive style in school‐aged children

The associations between sleep problems, anxiety, anxiety sensitivity and attributional style were examined in self‐report data from 79 children aged 8–11 years. Total anxiety score was associated with different types of sleep problems (bedtime resistance, sleep anxiety and nightmares). Conversely, total sleep problem score was associated with different sub‐scales of anxiety (from r(78) = 0.15, p = NS to r(79) = 0.47, p < 0.01). Symptoms of anxiety correlated significantly with anxiety sensitivity, but not with attributional style. After controlling for other symptoms of anxiety, school phobias (Beta = 0.26, p < 0.05), the mental incapacitation concerns scale of anxiety sensitivity (Beta = 0.26, p < 0.05), and attributional style (Beta = −0.31, p < 0.01, R² = 0.45) predicted sleep problems. These results suggest that anxiety is associated with a range of sleep problems, and that sleep problems are associated with different types of anxiety. Furthermore, certain cognitive styles are associated with both anxiety and sleep problems and may be good candidates for further research into the association between sleep problems and anxiety in children. Copyright © 2005 John Wiley & Sons, Ltd.     

Stress and dietary practices in adolescents.

Baseline data from the Health and Behavior in Teenagers Study (HABITS) were used to investigate associations between stress and dietary practices in a socioeconomically and ethnically diverse sample of 4,320 schoolchildren (mean age = 11.83 years). Male (n = 2,578) and female (n = 1,742) pupils completed questionnaire measures of stress and 4 aspects of dietary practice (fatty food intake, fruit and vegetable intake, snacking, and breakfast consumption) and also provided demographic and anthropometric data. Multivariate analyses revealed that greater stress was associated with more fatty food intake, less fruit and vegetable intake, more snacking, and a reduced likelihood of daily breakfast consumption. These effects were independent of individual (gender, weight) and social (socioeconomic status, ethnicity) factors. Stress may contribute to long-term disease risk by steering the diet in a more unhealthy direction.     

Psychometric evaluation of the Negative Religious Coping (NRC) Scale of the Brief RCOPE in the Czech environment

ABSTRACT

The Negative Religious Coping (NRC) Subscale is a part of the Brief RCOPE Scale, but can also be used separatelly. It is a brief measure assessing negative religous coping. The aim of this study was to psychometrically evaluate the NRC in Czech conditions. The NRC was administered to 531 religious respondents (25.5?±?3.4 years, 43.5% male). Negative religious coping and religiosity, together with basic sociodemographic information, were measured. The non-parametric comparison of different sociodemographic groups showed no differences between genders and almost no differences among the age groups. Significantly lower NRC scores were obtained by widows/widowers. The Czech version of the NRC showed a coherent one-dimensional factor structure and high reliability, with Cronbach’s α?=?.84 (95% CI .83–.85) and McDonald’s ω_t?=?.90. Our findings indicate that the Czech version of the NRC scale may reliably assess religious coping. This instrument might be useful both for research and clinical praxis.     

Response-time dynamics: Evidence for linear and low-dimensional nonlinear structure in human choice sequences

Response time (RT) is a commonly used measure of cognitive performance, which is usually characterized as stochastic. However, useful information may be hidden in the apparently random fluctuations of RT. Dynamical systems analysis techniques allow an exploration of the alternative hypothesis that RT fluctuations are deterministic, albeit in a complex manner. We applied careful task construction and noise-reduction and surrogate series tests to show that RT series from a forced-pace serial response-time task have low-dimensional chaotic characteristics. In Experiment 1, 80% of subjects' filtered RT series had low dimensionality, sensitive dependence on initial conditions, spectra close to 1/ f , and stable attractor geometry across sessions. In Experiment 2, we showed that the size of the inter-stimulus interval (ISI) determined the number of subjects with low-dimensional chaotic series. A small ISI caused 100% of subjects to respond in the chaotic regime, whereas only 25% had a low-dimensional chaotic RT component when the ISI was large. We argue that demanding task requirements cause a reduction in the dimensionality of the dynamics, producing RT fluctuations that may reflect a response strategy for controlling RT.