Behavioral and pharmacological variables affecting risky choice in rats.

The effects of manipulations of response requirement, intertrial interval (ITI), and psychoactive drugs (ethanol, phencyclidine, and d-amphetamine) on lever choice under concurrent fixed-ratio schedules were investigated in rats. Responding on the "certain' lever produced three 45-mg pellets, whereas responding on the "risky" lever produced either 15 pellets (p = .33) or no pellets (p .67). Rats earned all food during the session, which ended after 12 forced trials and 93 choice trials or 90 min, whichever occurred first. When the response requirement was increased from 1 to 16 and the ITI was 20 s, percentage of risky choice was inversely related to fixed-ratio value. When only a single response was required but the ITI was manipulated between 20 and 120 s (with maximum session duration held constant), percentage of risky choice was directly related to length of the ITI. The effects of the drugs were investigated first at an ITI of 20 s, when risky choice was low for most rats, and then at an ITI of 80 s, when risky choice was higher for most rats. Ethanol usually decreased risky choice. Phencyclidine did not usually affect risky choice when the ITI was 20 s but decreased it in half the rats when the ITI was 80 s. For d-amphetamine, the effects appeared to he related to baseline probability of risky choice; that is, low probabilities were increased and high probabilities were decreased. Although increase in risky choice as a function of the ITI is at variance with previous ITI data, it is consistent with foraging data showing that risk aversion decreases as food availability decreases. The pharmacological manipulations showed that drug effects on risky choice may be influenced by the baseline probability of risky choice, just as drug effects can be a function of baseline response rate.     

Psychoanalysis and Diplomacy: Part I. Individual and Large Group Identity

Starting with Sigmund Freud, psychoanalysts have written on a variety of topics relating to the diplomatic and political realms; but thus far their contributions primarily have been theoretical in nature, and have offered little of practical use to most diplomats and politicians. Various psychoanalytic theories have been applied, resulting in diverse conceptualizations: Wars are inevitable because of our inherent aggressive drives; a nation-state serves a maternal function for its members; certain large groups exhibit behaviors similar to those of adolescents. Yet these ideas do not significantly help us understand day-to-day events around the world, practical political issues, or international relations and diplomatic decisions.     

Psychoanalysis and Diplomacy: Part III. Potentials for and Obstacles Against Collaboration

Given the pervasive influence of Realpolitik over government and the study of international relations, and some inherent difficulties within the field of psychoanalysis, it is not surprising that political science and psychoanalysis remain distant cousins. Part III in this series on diplomacy and psychoanalysis discusses obstacles against collaboration between these two disciplines, but also points to areas where collaboration is possible and can be useful.     

Latent variables should remain as such: Evidence from a Monte Carlo study

Use of subject scores as manifest variables to assess the relationship between latent variables produces attenuated estimates. This has been demonstrated for raw scores from classical test theory (CTT) and factor scores derived from factor analysis. Conclusions on scores have not been sufficiently extended to item response theory (IRT) theta estimates, which are still recommended for estimation of relationships between latent variables. This is because IRT estimates appear to have preferable properties compared to CTT, while structural equation modeling (SEM) is often advised as an alternative to scores for estimation of the relationship between latent variables. The present research evaluates the consequences of using subject scores as manifest variables in regression models to test the relationship between latent variables. Raw scores and three methods for obtaining theta estimates were used and compared to latent variable SEM modeling. A Monte Carlo study was designed by manipulating sample size, number of items, type of test, and magnitude of the correlation between latent variables. Results show that, despite the advantage of IRT models in other areas, estimates of the relationship between latent variables are always more accurate when SEM models are used. Recommendations are offered for applied researchers.     

A Bootstrapping Model of Frequency and Context Effects in Word Learning

Prior research has shown that people can learn many nouns (i.e., word–object mappings) from a short series of ambiguous situations containing multiple words and objects. For successful cross‐situational learning, people must approximately track which words and referents co‐occur most frequently. This study investigates the effects of allowing some word‐referent pairs to appear more frequently than others, as is true in real‐world learning environments. Surprisingly, high‐frequency pairs are not always learned better, but can also boost learning of other pairs. Using a recent associative model (Kachergis, Yu, & Shiffrin, 2012), we explain how mixing pairs of different frequencies can bootstrap late learning of the low‐frequency pairs based on early learning of higher frequency pairs. We also manipulate contextual diversity, the number of pairs a given pair appears with across training, since it is naturalistically confounded with frequency. The associative model has competing familiarity and uncertainty biases, and their interaction is able to capture the individual and combined effects of frequency and contextual diversity on human learning. Two other recent word‐learning models do not account for the behavioral findings.     

Identification With All Humanity: The role of self‐definition and self‐investment

Identification With All Humanity (IWAH) relates to higher levels of concern and supportive behavior toward the disadvantaged, stronger endorsement of human rights, and stronger responses in favor of global harmony. So far, IWAH has been conceptualized as a one‐dimensional construct describing the degree with which one identifies with all humans as a superordinate ingroup. However, recent group identification models suggest a multi‐dimensional model to provide a more differentiated approach toward the understanding of the highest level of social identification. Using principal axis (Study 1) and confirmatory (Study 2) factor analyses, we suggest that IWAH sub‐divides into two dimensions—global self‐definition and global self‐investment. Study 2 revealed that global self‐investment was a stronger predictor for both convergent measures (e.g., social dominance orientation and authoritarianism) and behavioral intentions than global self‐definition. Finally, in Study 3, we manipulated IWAH to test its causal effect on donation behavior. Participants in the experimental condition, compared with the control condition, showed higher global self‐investment, which in turn predicted greater giving to global charity. These findings suggest that two dimensions with different behavioral outcomes underlie IWAH.     

Laterality effects in the spinning dancer illusion: The viewing‐from‐above bias is only part of the story

The ‘silhouette illusion’, representing the silhouette of a female dancer pirouetting about her vertical axis, is a bistable stimulus created by Japanese web designer Nobuyuki Kayahara. Although the dancer can be perceived as spinning either clockwise or counterclockwise, the clockwise rotation is usually preferred. Troje and McAdam (i‐Perception, 2010, 1, 143) showed that this clockwise bias can be attributed to the tendency to assume a viewpoint from above rather than from below, given that the dancer is portrayed from a vantage point that is not perpendicular to the axis of rotation. Here, we tested whether another possible factor contributing to the observers’ interpretation of this bistable stimulus might be the tendency to perceive movements of the right rather than the left foot. We confirmed both the viewing‐from‐above bias and our hypothesis. The bias to perceive movements of the right leg might be a generalization to lower limbs of a perceptual frequency effect already observed for upper limbs. Such a perceptual and attentional bias towards the right hand/foot could account for the greater ability to predict the outcome of sport actions when observing right‐ rather than left‐limbed movements, and thus the left‐handers' and left‐footers' advantage observed in a variety of interactive sports.     

A Computational Evaluation of Sentence Processing Deficits in Aphasia

Individuals with agrammatic Broca's aphasia experience difficulty when processing reversible non‐canonical sentences. Different accounts have been proposed to explain this phenomenon. The Trace Deletion account (Grodzinsky, 1995, 2000, 2006) attributes this deficit to an impairment in syntactic representations, whereas others (e.g., Caplan, Waters, Dede, Michaud, & Reddy, 2007; Haarmann, Just, & Carpenter, 1997) propose that the underlying structural representations are unimpaired, but sentence comprehension is affected by processing deficits, such as slow lexical activation, reduction in memory resources, slowed processing and/or intermittent deficiency, among others. We test the claims of two processing accounts, slowed processing and intermittent deficiency, and two versions of the Trace Deletion Hypothesis (TDH), in a computational framework for sentence processing (Lewis & Vasishth, 2005) implemented in ACT‐R (Anderson, Byrne, Douglass, Lebiere, & Qin, 2004). The assumption of slowed processing is operationalized as slow procedural memory, so that each processing action is performed slower than normal, and intermittent deficiency as extra noise in the procedural memory, so that the parsing steps are more noisy than normal. We operationalize the TDH as an absence of trace information in the parse tree. To test the predictions of the models implementing these theories, we use the data from a German sentence—picture matching study reported in Hanne, Sekerina, Vasishth, Burchert, and De Bleser (2011). The data consist of offline (sentence‐picture matching accuracies and response times) and online (eye fixation proportions) measures. From among the models considered, the model assuming that both slowed processing and intermittent deficiency are present emerges as the best model of sentence processing difficulty in aphasia. The modeling of individual differences suggests that, if we assume that patients have both slowed processing and intermittent deficiency, they have them in differing degrees.     

Challenges in Developing a Cultural Evidence‐Based Psychotherapy in the USA: Suggestions for International Studies

In this article, we underscore some of the cultural challenges and limitations of the evidence‐based psychotherapy (EBP) utilised within the USA with the hope that these problems will be avoided or ameliorated in Australia and other countries. Although the EBP research is very diverse and complex, we categorise this fast‐growing literature using a threefold classification system that underscores culture. This classification system is proposed to examine the influence of culture on EBPs. The three categories used are (a) universal evidence‐based psychotherapies or universal psychotherapies, (b) race and ethnic minority evidence‐based psychotherapies or racial/ethnic psychotherapies, and (c) cultural evidence‐based psychotherapies or cultural psychotherapies. After each category is described, its benefits and limitations are discussed, emphasising implications for culturally diverse and international studies. We conclude with suggestions to promote the advancement of a more effective and inclusive cultural EBP in which researchers from different countries can collaborate and learn from each other.     

基于两水平回归模型的调节效应分析及其效应量

使用多元回归法进行调节效应分析在社科领域已常有应用。简述了目前多元回归法的调节效应分析存在的不足,包括人为变换检验模型、自变量和调节变量区分不足、误差方差齐性的假设难以满足、调节效应量指标ΔR²没有直接测量调节变量对自变量与因变量关系的调节程度。比较好的方法是用两水平回归模型进行调节效应分析并使用相应的效应量指标。在介绍新方法和新效应量后,总结出一套调节效应的分析流程,通过一个例子来演示如何用Mplus软件进行两水平回归模型的调节效应及其效应量分析。最后讨论了两水平回归模型的调节效应分析的发展,包括稳健的调节效应分析、潜变量的调节效应分析、有调节的中介效应分析和有中介的调节效应分析等。