Further Support for Multidimensionality Within the Rosenberg Self-Esteem Scale

Although the Rosenberg Self Esteem Scale is one of the most widely used measures of global self esteem, the underlying measurement structure of the items is still debated. In this study the dimensionality of a six item version of the Rosenberg Self Esteem Scale included in the National Population Health Survey of Canada was examined using nested confirmatory factor analyses. The results indicate that the six items measure two correlated dimensions of global self esteem. The first dimension appears to represent a measure of self competence, and the second is interpreted as a measure of self liking. Subsequent tests of predictive power and discriminant validity supported the two dimension interpretation. The two dimensions had substantially different relationships with theoretically related measures of anxiety, negative affect and happiness. In addition to these different correlations, latent variable regressions indicated that the self-competency factor consistently suppressed irrelevant variance in the self liking factor when predicting anxiety, negative affect and happiness.     

Pigeons' memory for number of events: Effects of intertrial interval and delay interval illumination

In Experiment 1, pigeons were trained at a 0-s baseline delay to discriminate sequences of light flashes (illumination of the feeder) that varied in number but not time (2f/4s and 8f/4s). During training, the intertrial interval was illuminated by the houselight for Group Light, but it was dark for Group Dark. Testing conducted with dark delay intervals produced a strong choose-small bias in both groups. All birds then received baseline training with a 5-s dark delay and were subsequently tested at shorter and longer dark delays. A choose-small bias was again observed at delays longer than the training delay, while a choose-large bias occurred at delays shorter than the training delay. Differentiating the ambient chamber illumination during the intertrial interval and the delay interval did not attenuate choose-small or choose-large effects. In Experiment 2, all birds received baseline training with a 5-s illuminated delay and were subsequently tested at shorter and longer illuminated delays. A choose-large bias was observed at delays longer than the training delay, while a choose-small bias occurred at delays shorter than the training delay. In Experiment 3, on intermittent test trials, when the duration of the second flash on small-sample trials was equal to the total flash duration on large-sample trials (i.e., 1600 ms), accuracy fell to approximately chance. These results suggest that pigeons discriminated the sequences of light flashes that varied in number but not in total duration of the sequence by relying on other temporal properties of the sequence rather than by using an event switch to count flashes.     

Socioeconomic variation in attitudes to eating and weight in female adolescents.

This study was stimulated by J. Sobal and A. J. Stunkard's (1989) theory that differences in deliberate weight control could underlie the socioeconomic gradient in adult weight. Female adolescents (N=1,248) completed measures of socioeconomic status, social norms for weight, weight ideals, attitudes to weight, and weight control behaviors. Higher socioeconomic status adolescents had greater awareness of the social ideals of slimness and had more family and friends who were trying to lose weight. They also defined a lower body mass index as "fat" and were more likely to have used healthy weight control methods. The results support the idea that socioeconomic differences in weight-related attitudes and behaviors may mediate the development of a gradient in weight.     

Differing time dependencies of object recognition memory impairments produced by nicotinic and muscarinic cholinergic antagonism in perirhinal cortex

The roles of muscarinic and nicotinic cholinergic receptors in perirhinal cortex in object recognition memory were compared. Rats' discrimination of a novel object preference test (NOP) test was measured after either systemic or local infusion into the perirhinal cortex of the nicotinic receptor antagonist methyllycaconitine (MLA), which targets alpha-7 (α7) amongst other nicotinic receptors or the muscarinic receptor antagonists scopolamine, AFDX-384, and pirenzepine. Methyllycaconitine administered systemically or intraperirhinally before acquisition impaired recognition memory tested after a 24-h, but not a 20-min delay. In contrast, all three muscarinic antagonists produced a similar, unusual pattern of impairment with amnesia after a 20-min delay, but remembrance after a 24-h delay. Thus, the amnesic effects of nicotinic and muscarinic antagonism were doubly dissociated across the 20-min and 24-h delays. The same pattern of shorter-term but not longer-term memory impairment was found for scopolamine whether the object preference test was carried out in a square arena or a Y-maze and whether rats of the Dark Agouti or Lister-hooded strains were used. Coinfusion of MLA and either scopolamine or AFDX-384 produced an impairment profile matching that for MLA. Hence, the antagonists did not act additively when coadministered. These findings establish an important role in recognition memory for both nicotinic and muscarinic cholinergic receptors in perirhinal cortex, and provide a challenge to simple ideas about the role of cholinergic processes in recognition memory: The effects of muscarinic and nicotinic antagonism are neither independent nor additive.     

Does money really matter? Estimating impacts of family income on young children's achievement with data from random-assignment experiments

Social scientists do not agree on the size and nature of the causal impacts of parental income on children's achievement. We revisit this issue using a set of welfare and antipoverty experiments conducted in the 1990s. We utilize an instrumental variables strategy to leverage the variation in income and achievement that arises from random assignment to the treatment group to estimate the causal effect of income on child achievement. Our estimates suggest that a $1,000 increase in annual income increases young children's achievement by 5%-6% of a standard deviation. As such, our results suggest that family income has a policy-relevant, positive impact on the eventual school achievement of preschool children.     

Are smokers interested in genetic testing for smoking addiction? A socio-cognitive approach

Genetic advances have made genetically tailored smoking cessation treatments possible. In this study, we examined whether smokers are interested in undergoing a genetic test to identify their genetic susceptibility to nicotine addiction. In addition, we aimed to identify socio-cognitive determinants of smokers' intention to undergo genetic testing. Following the protection motivation theory (PMT), we assessed the following constructs using an online survey among 587 smokers: threat appraisal (i.e. susceptibility and severity), fear, coping appraisal (i.e. response efficacy and self-efficacy), response costs and intention. In addition, knowledge, social norms and information-seeking behaviour were measured. Mean intention rates were 2.57 on a 5-point scale. Intention was significantly associated with threat appraisal and coping appraisal, as predicted by the PMT. Fear of the outcome was negatively associated with the intention to undergo genetic testing, but response costs, knowledge and social influence were not. Intention to undergo genetic testing in turn was positively related to seeking information about genetic testing and genetically tailored smoking cessation treatments. Smokers seem ambivalent or 'on the fence' with regard to undergoing a genetic test for smoking addiction. Socio-cognitive concepts such as susceptibility, severity, response efficacy and self-efficacy may be used to inform or educate smokers about the value of genetically tailored smoking cessation treatments.     

Reliability and construct validity of the College Student Stress Scale

Reliability and construct validity of the 11-item College Student Stress Scale were investigated with exploratory (N = 273) and confirmatory factor analyses (N = 185) in undergraduate college students. Two factors were observed; however, reliability of the 3-item factor was too low and one item failed to load on either factor. A 7-item measure (Factor 1) had acceptable reliability (.81) and good convergence with the Perceived Stress Scale. This measure was significantly correlated with Neuroticism, Test Anxiety, and Self-efficacy for Learning, but not Social Desirability or age.     

Rapid averaging? Not so fast!

Previous research suggests that sets of similar items are represented using a rapid averaging mechanism that automatically extracts statistical properties within 50 ms. However, typically in these studies, displays are not masked, so it is possible that the sets are available for longer than this duration. In the present study, using masked displays, we (a) tested a newly proposed strategy for extracting the mean size of a set of circles, and (b) more precisely evaluated the time course of rapid averaging. The results indicate that when viewing conditions are poor, performance can be explained by assuming that observers rely on information from previous trials. In this study, observers required at least a 200-ms exposure time in order to derive the average size of a set of circles without relying on information from previously-viewed sets, suggesting that rapid averaging is not as fast as previously assumed and, therefore, that it may not be an automatic process.