Decreased aggressive and locomotor behaviors in Betta splendens after exposure to fluoxetine

The failure of sewage treatment plants to remove pharmaceuticals such as fluoxetine from waste water has become a concern given that these products are being detected in the surface waters of many countries of the world. The effects of fluoxetine in sub-lethal doses on the neural systems and behaviors of aquatic life are worthy of investigation. This study investigated the effects of sub-lethal amounts fluoxetine dissolved in water on the aggressive and locomotor behaviors of 44 male Betta splendens. Fish treated with 705 microg/l of fluoxetine and 350 microg/l of fluoxetine generally demonstrated significant decreases in locomotion and number of aggressive attacks compared to 0 microg/l of fluoxetine (controls) on Days 11 and 19 of drug exposure and persisted for at least 13 days after removal of fluoxetine. Consistent with decreases in the number of aggressive attacks, there was a significant increase in aggression-response time to a perceived intruder for treated males on Days 11 and 19 and persisted for 6 days following removal of fluoxetine. However, the differences in aggressive and locomotor behaviors seen in the fluoxetine-treated groups were indistinguishable from controls three weeks following drug removal.     

Performing well - Feeling bad? Effects of perfectionism under experimentally induced stress on tension and performance

The present study explored the influence of dispositional perfectionism (i.e. perfectionistic concerns and perfectionistic strivings) on tension and performance under low or high experimentally induced stress. Results support the moderating role of perfectionism concerning tension and indicate that stress-related processes underlie the vulnerability of perfectionistic concerns. In addition, buffering effects of perfectionistic strivings were found, supporting the 2 × 2 model of dispositional perfectionism by Gaudreau and Thompson (2010). No evidence was found for the moderating role of perfectionistic strivings concerning performance, but results provide evidence for positive effects of perfectionistic concerns on performance.     

Accuracy in parameter estimation for ANCOVA and ANOVA contrasts: sample size planning via narrow confidence intervals

Contrasts of means are often of interest because they describe the effect size among multiple treatments. High-quality inference of population effect sizes can be achieved through narrow confidence intervals (CIs). Given the close relation between CI width and sample size, we propose two methods to plan the sample size for an ANCOVA or ANOVA study, so that a sufficiently narrow CI for the population (standardized or unstandardized) contrast of interest will be obtained. The standard method plans the sample size so that the expected CI width is sufficiently small. Since CI width is a random variable, the expected width being sufficiently small does not guarantee that the width obtained in a particular study will be sufficiently small. An extended procedure ensures with some specified, high degree of assurance (e.g., 90% of the time) that the CI observed in a particular study will be sufficiently narrow. We also discuss the rationale and usefulness of two different ways to standardize an ANCOVA contrast, and compare three types of standardized contrast in the ANCOVA/ANOVA context. All of the methods we propose have been implemented in the freely available MBESS package in R so that they can be easily applied by researchers.     

Verbal interference suppresses exact numerical representation

Language for number is an important case study of the relationship between language and cognition because the mechanisms of non-verbal numerical cognition are well-understood. When the Pirahã (an Amazonian hunter-gatherer tribe who have no exact number words) are tested in non-verbal numerical tasks, they are able to perform one-to-one matching tasks but make errors in more difficult tasks. Their pattern of errors suggests that they are using analog magnitude estimation, an evolutionarily- and developmentally-conserved mechanism for estimating quantities. Here we show that English-speaking participants rely on the same mechanisms when verbal number representations are unavailable due to verbal interference. Followup experiments demonstrate that the effects of verbal interference are primarily manifest during encoding of quantity information, and—using a new procedure for matching difficulty of interference tasks for individual participants—that the effects are restricted to verbal interference. These results are consistent with the hypothesis that number words are used online to encode, store, and manipulate numerical information. This linguistic strategy complements, rather than altering or replacing, non-verbal representations.     

Sexy Dolls, Sexy Grade-Schoolers? Media & Maternal Influences on Young Girls’ Self-Sexualization

Concern is often expressed that mass media contribute to the early sexualization of young girls; however, few empirical studies have explored the topic. Using paper dolls, we examined self-sexualization among sixty 6–9?year-old girls from the Midwestern United States; specifically self-identification, preference, and attributions regarding sexualized dress. Based on simultaneous maternal reports, we also investigated potential risk factors (media consumption hours, maternal self-objectification) and potential protective factors (maternal television mediation, maternal religiosity) for young girls’ sexualization. Findings support social cognitive theory/social learning theory and reveal nuanced moderated effects in addition to linear main effects. Girls overwhelmingly chose the sexualized doll over the non-sexualized doll for their ideal self and as popular; however, dance studio enrollment, maternal instructive TV mediation, and maternal religiosity reduced those odds. Surprisingly, the mere quantity of girls’ media consumption (tv and movies) was unrelated to their self-sexualization for the most part; rather, maternal self-objectification and maternal personal religiosity moderated its effects.     

We're all in this together now: group performance feedback to increase classroom team data collection

This study's primary goal was to evaluate the use of performance feedback procedures delivered to a classroom team to increase daily data collection. Performance feedback (PFB) was delivered to four classroom teams responsible for the daily collection of data representing student performance during prescribed instructional activities. Using a multiple-baseline design, the effects of the team performance-feedback were evaluated for the target student, and for generalization to data collection for all classroom students. A secondary question evaluated if student on-task behavior correlated with increased data collection. Finally, social validity was investigated to evaluate team satisfaction with the PFB intervention. The results demonstrate improved data collection across all four classroom teams for the target student in each classroom and generalization within classrooms to all remaining students. Slight increases in student on-task behavior were observed in three of the four classrooms, and teacher satisfaction ratings were high.     

Self as the Target and the Perceiver: A Componential Approach to Self-Enhancement

In this paper, we review the recent literature on the debate over the value of self-enhancement. Past studies fall into two distinct sets, each in the context of a different research tradition. The componential approach to self-enhancement integrates these two divergent perspectives and takes seriously the interplay of self-perception and interpersonal perception. Instead of global indices, the componential approach identifies specific components of person perception. By partitioning the components in self-perception, the componential approach allows for better understanding of the dynamic interactive effects of self-enhancement bias and other components in self-perception on adjustment. We conclude the paper by discussing the emerging attempts to advance a componential approach to examine self-perception in terms of components and outcomes.     

Effect of visual-verbal load and spatial compatibility on stimulus response

This study examined the effects of visual-verbalload (as measured by a visually presented reading-memory task with three levels) on a visual/auditory stimulus-response task. The three levels of load were defined as follows: "No Load" meant no other stimuli were presented concurrently; "Free Load" meant that a letter (A, B, C, or D) appeared at the same time as the visual or auditory stimulus; and "Force Load" was the same as "Free Load," but the participants were also instructed to count how many times the letter A appeared. The stimulus-response task also had three levels: "irrelevant," "compatible," and "incompatible" spatial conditions. These required different key-pressing responses. The visual stimulus was a red ball presented either to the left or to the right of the display screen, and the auditory stimulus was a tone delivered from a position similar to that of the visual stimulus. Participants also processed an irrelevant stimulus. The results indicated that participants perceived auditory stimuli earlier than visual stimuli and reacted faster under stimulus-response compatible conditions. These results held even under a high visual-verbal load. These findings suggest the following guidelines for systems used in driving: an auditory source, appropriately compatible signal and manual-response positions, and a visually simplified background.     

Motivational predictors of coping with academic examination

The present study focused on the motivational predictors of coping with academic examination through the test of the contribution of self-determination for academic studies and achievement goals. Coping strategies, academic motivation and achievement goals were assessed among 199 undergraduate students. Regression analysis revealed that problem-focused coping is positively predicted by identified regulation and negatively by amotivation, whereas emotion-focused coping is positively predicted by introjected regulation and amotivation. Mastery approach goals contributed positively to problem-focused coping. Identified regulation and mastery approach goals made a unique positive contribution to problem-focused coping, and amotivation was negatively related. Students' coping actions may vary according to both the reasons why they engage in academic studies and the goals they pursue in this setting.