USING PERCENTILE SCHEDULES TO INCREASE EYE CONTACT IN CHILDREN WITH FRAGILE X SYNDROME

Aversion to eye contact is a common behavior of individuals diagnosed with Fragile X syndrome (FXS); however, no studies to date have attempted to increase eye‐contact duration in these individuals. In this study, we employed a percentile reinforcement schedule with and without overcorrection to shape eye‐contact duration of 6 boys with FXS. Results showed that although aversion to eye contact is often thought to be unamenable to change in FXS, it can be shaped in some individuals using percentile schedules either alone or in combination with overcorrection.     

Enhanced latent inhibition in context aversion conditioning

In four experiments, we investigated the effect of giving rats exposure to a distinctive environmental context before a phase of training in which an injection of LiCl was paired with that context. The results of Experiments 1 and 2 were consistent with the possibility that such preexposure served to retard subsequent conditioning to the context (i.e., produced a latent inhibition effect). Experiments 3 and 4 demonstrated that allowing the rats to consume a novel-flavored solution during preexposure enhanced the latent inhibition effect. The relevance of these findings both for theories of latent inhibition and for the use of preexposure as a clinical intervention for the reduction of conditioned nausea in humans is considered.     

Personality traits of Russians from the observer's perspective

Data were collected by the members of the Russian character and personality survey from 39 samples in 33 administrative areas of the Russian Federation. Respondents (N = 7065) identified an ethnically Russian adult or college‐aged man or woman whom they knew well and rated the target using the Russian observer rating version of the Revised NEO Personality Inventory, which measures neuroticism, extraversion, openness to experience, agreeableness and conscientiousness. Factor analyses within samples showed that the factor structure of an international sample combining data from 50 different cultures was well replicated in all 39 Russian samples. Sex differences replicated the known pattern in all samples, demonstrating that women scored higher than men on most of the neuroticism, openness, agreeableness and conscientiousness facet scales. Cross‐sectional analyses demonstrated consistent age differences for four factors: Older individuals compared to younger ones were less extraverted and open but more agreeable and conscientious. The mean levels of traits were similar in all 39 samples. Although in general personality traits in Russians closely followed the universal pattern, some reliable culture‐specific effects were also found that future studies can help interpret. Copyright © 2009 John Wiley & Sons, Ltd.     

Dynamic representations underlying symbolic and nonsymbolic calculation: Evidence from the operational momentum effect

When we add or subtract, do the corresponding quantities “move” along a mental number line? Does this internal movement lead to spatial biases? A new method was designed to investigate the psychophysics of approximate arithmetic. Addition and subtraction problems were presented either with sets of dots or with Arabic numerals, and subjects selected, from among seven choices, the most plausible result. In two experiments, the subjects selected larger numbers for addition than for subtraction problems, as if moving too far along the number line. This operational momentum effect was present in both notations and increased with the size of the outcome. Furthermore, we observed a new effect of spatial-numerical congruence, related to but distinct from the spatial numerical association of response codes effect: During nonsymbolic addition, the subjects preferentially selected numbers at the upper right location, whereas during subtraction, they were biased toward the upper left location. These findings suggest that approximate mental arithmetic involves dynamic shifts on a spatially organized mental representation of numbers. Supplemental materials for this study may be downloaded from app.psychonomic-journals.org/content/supplemental.