Fear of snakes and facial reactions: A case of rapid emotional responding

The aim of the present study was to explore how rapid emotional responses are manifested as facial electromyographic (EMG) reactions when people with explicit fear of snakes are exposed to their fear relevant stimuli. Fifty-six subjects, high or low in fear of snakes, were exposed to pictures of snakes and flowers while facial EMG activity from the corrugator supercilii and the zygomatic major muscle regions was recorded. Measures of autonomic activity and ratings of the stimuli were also collected. Pictures of snakes evoked a rapid corrugator supercilii muscle reaction which was larger in the High fear group as early as 500ms after stimulus onset. The High fear group also rated snakes as more unpleasant and displayed larger skin conductance responses (SCRs) and increased heart rate (HR) when exposed to snakes. Pictures of flowers tended to evoke increased zygomatic major muscle activity which did not differ among the groups. The present results demonstrate that the facial EMG technique is sensitive enough to detect rapidly evoked negative emotional reactions. The results support the hypothesis that people high in fear of snakes are disposed to react very rapidly with a negative emotional response to their fear relevant stimuli.     

The effects of attractiveness, dominance, and attribute differences on information acquisition in multiattribute binary choice

Two process tracing studies investigated how the information acquisition process in a binary choice task is influenced by the overall level of attractiveness of alternatives, by the magnitude of differences in attractiveness of alternatives, and by the dominance of one alternative. All three factors influenced the subjects' information selection process regarding the multiattribute choice alternatives. Subjects selected more information when the attractiveness difference was small and when one of the alternatives was not dominant. Moreover, they considered more information when the choice alternatives were both unattractive. These findings were obtained when information was presented about the alternatives both numerically and nonnumerically. The experimental results were explained within a sequential sampling strategy framework.     

An INAR(1) negative multinomial regression model for longitudinal count data

This paper discusses a regression model for the analysis of longitudinal count data observed in a panel study. An integer-valued first-order autoregressive [INAR(1)] Poisson process is adapted to represent time-dependent correlations among the counts. By combining the INAR(1)-representation with a random effects approach, a new negative multinomial distribution is derived that includes the bivariate negative binomial distribution proposed by Edwards and Gurland (1961) and Subrahmaniam (1966) as a special case. A detailed analysis of the relationship between personality factors and daily emotion experiences illustrates the approach.This research was partially supported by NSF grant SBR-9409531. The author is grateful to Ulrich Schimmack and Ed Diener for providing the data set used in the application section and for helpful comments on this research.     

RODS AS COLOR RECEPTORS IN PHOTOPIC VISION

Comparing a foveal and an extra-foveal field during dark adaptation, transition from chromatic to achromatic vision at intensity levels above the cone plateau started around the break of the dark adaptation curve. Pre-stimulating the two fields in a dark-adapted state with deep red, and test-stimulating when returning sensitivity had reached absolute threshold of the dark-adapted eye, with green filters at intensities above the specific threshold, the fields matched as to hue and saturation. It appears that rod and cone activities are integrated and function as a synchronized unit during the initial recovery phase of dark adaptation.     

PERCEIVED INTENSITY OF ODOR AS A FUNCTION OF TIME OF ADAPTATION

The perceived intensity of odor under conditions of constant stimulation with hydrogen sulphide was investigated in two experiments. A two-step scaling method, involving cross-modality matching and numerical scaling of the matching continuum, was used for measuring intensity of odor. Perceptual intensity was found to decrease exponentially with increase of time of stimulation. Preliminary data concerning the subsequent recovery phase were also obtained.     

COLOR THRESHOLD MEASUREMENTS IN SCOTOPIC VISION

The absolute and the color threshold in scotopic vision generally coincide during dark adaptation, indicating that color-threshold intensity is a measure of the concentration of rhodopsin, and that different modes of rhodopsin regeneration are reflected in the measurements of the color threshold.     

Working memory as a predictor of written arithmetical skills in children: The importance of central executive functions

Background . The study was conducted in an attempt to further our understanding of how working memory contributes to written arithmetical skills in children. Aim . The aim was to pinpoint the contribution of different central executive functions and to examine the contribution of the two subcomponents of children's written arithmetical skills. Sample and method . A total of 141 third‐ and fourth‐graders were administered arithmetical tasks and measures of working memory, fluid IQ and reading. Regression analysis was used to examine the relationship between working memory and written arithmetical skills. Results . Three central executive measures (counting span, trail making and verbal fluency) and one phonological loop measure (Digit Span) were significant and predictors of arithmetical performance when the influence of reading, age and IQ was controlled for in the analysis. Conclusions . The present findings demonstrate that working memory, in general, and the central executive, in particular, contribute to children's arithmetical skills. It was hypothesized that monitoring and coordinating multiple processes, and accessing arithmetical knowledge from long‐term memory, are important central executive functions during arithmetical performance. The contribution of the phonological loop and the central executive (concurrent processing and storage of numerical information) indicates that children aged 9–10 years primarily utilize verbal coding strategies during written arithmetical performance.     

Twelve-month-olds communicate helpfully and appropriately for knowledgeable and ignorant partners

In the current study we investigated whether 12-month-old infants gesture appropriately for knowledgeable versus ignorant partners, in order to provide them with needed information. In two experiments we found that in response to a searching adult, 12-month-olds pointed more often to an object whose location the adult did not know and thus needed information to find (she had not seen it fall down just previously) than to an object whose location she knew and thus did not need information to find (she had watched it fall down just previously). These results demonstrate that, in contrast to classic views of infant communication, infants' early pointing at 12 months is already premised on an understanding of others' knowledge and ignorance, along with a prosocial motive to help others by providing needed information.     

The contribution of working memory to children's mathematical word problem solving

The study explored the contribution of working memory to mathematical word problem solving in children. A total of 69 children in grades 2, 3 and 4 were given measures of mathematical problem solving, reading, arithmetical calculation, fluid IQ and working memory. Multiple regression analyses showed that three measures associated with the central executive and one measure associated with the phonological loop contributed unique variance to mathematical problem solving when the influence of reading, age and IQ were controlled for in the analysis. In addition, the animal dual‐task, verbal fluency and digit span task continued to contribute unique variance when the effects of arithmetical calculation in addition to reading, fluid IQ, and age were controlled for. These findings demonstrate that the phonological loop and a number of central executive functions (shifting, co‐ordination of concurrent processing and storage of information, accessing information from long‐term memory) contribute to mathematical problem solving in children. Copyright © 2006 John Wiley & Sons, Ltd.     

Comparative judgments as an alternative to ratings: identifying the scale origin

Although comparative judgment methods have a number of distinct advantages over ratings, they share one common problem: On the basis of comparative judgments, it is not possible to recover the origin of item evaluations. One item may be judged more positively than another, but this result does not allow any conclusions about whether either of the items are attractive or unattractive. This article discusses the implications of this limitation for the interpretation of individual differences in comparative judgments. It also presents 3 different methods that may allow determination of the scale origin using a nested model comparison approach. An application illustrates the proposed approach as well as the benefits of determining the scale origin in understanding value judgments.