The influence of saccade length on the saccadic suppression of displacement detection

The decrease in sensitivity to spatial displacement which accompanies a voluntary horizontal saccadic eye movement was measured as a function of the length of the saccade. Threshold for detecting the displacement increased linearly from about 0.3 degrees to 1.2 degrees as saccade length increased from 4 degrees to 12 degrees. The variability (standard deviation) of the discrimination increased linearly with saccade length as well, and hence also linearly with the displacement threshold. These results, along with our previous finding that the increase is not a consequence of the saccadically generated spatiotemporal smearing of the retinal image (Li & Matin, 1990), support the proposal that displacement detection is based on a constant internal signal/noise ratio whose denominator is a measure of the variability of the extraretinal signal regarding eye position, and that the reduction in sensitivity is a result of a transient increase of this variability in the temporal neighborhood of a saccade.     

The impact of stress on the life history strategies of African American adolescents: cognitions, genetic moderation, and the role of discrimination

The impact of 3 different sources of stress--environmental, familial (e.g., low parental investment), and interpersonal (i.e., racial discrimination)--on the life history strategies (LHS) and associated cognitions of African American adolescents were examined over an 11-year period (5 waves, from age 10.5 to 21.5). Analyses indicated that each one of the sources of stress was associated with faster LHS cognitions (e.g., tolerance of deviance, willingness to engage in risky sex), which, in turn, predicted faster LHS behaviors (e.g., frequent sexual behavior). LHS, then, negatively predicted outcome (resilience) at age 21.5 (i.e., faster LHS → less resilience). In addition, presence of the risk ("sensitivity") alleles of 2 monoamine-regulating genes, the serotonin transporter gene (5HTTLPR) and the dopamine D4 receptor gene (DRD4), moderated the impact of perceived racial discrimination on LHS cognitions: Participants with more risk alleles (higher "sensitivity") reported faster LHS cognitions at age 18 and less resilience at age 21 if they had experienced higher amounts of discrimination and slower LHS and more resilience if they had experienced smaller amounts of discrimination. Implications for LHS theories are discussed.     

Constructing Self-Identity: Minority Students’ Adaptation Trajectories in a Chinese University

Researchers have gone beyond identity status and been putting more and more emphases on the dynamic process of identity development and its contextual embeddedness. Study of individual’s adaptation to the multicultural background is a good point of penetration. Because of the differences in regional conditions and cultural traditions, the minority youths who go to university in the mainstream culture would have special experiences and challenges in the development of their self-identities. Semi-structured interview and narrative were used in this research to discover the characteristics of the self-identity constructing processes of Mongolian undergraduates in a Shanghai university context. Their identity constructing process could be divided into three stages: difference-detecting, self-doubting and self-orienting. The main efforts of identity constructing in each stage could all be described as self-exploring and support-seeking. Special contents of internal explorations and sources of support were distinguished at different stages. As relative results, three main types of self-orientation were revealed: goal-oriented, self-isolated and unreserved assimilated. The characteristics of them are quite similar to those of three identity processing styles proposed by Berzonsky, which indicates there are some common elements lying in all self-development processes of adolescences and young adults. Ethnicity and culture could be background and resource or what Côté called identity capital that impacts the special course of self-identity constructing under similar principles. Different attitudes towards and relationships with their own ethnicity and new surroundings separated the three types of students from each other and interacted with the developmental characteristics and tendencies of their ethnicity identifications and self identities. It was found that minority youths’ self-identity constructing was based on their needs of self-value and interacted with their ecological niche constructing. Take ethnicity attachment and ethnicity responsibility as a typical example: the setting up of bi-direction relationship between individuals and their ethnicity (or other identity-related factors) was very important for minority youths to expand and integrate themselves. We also presented in detail our methodological exploring process so as to illuminate the limitation of traditional methods and the necessity and importance of methodological reform. Methodologically, both emic and etic positions were taken, interview and narrative approaches were adopted and individual angle of analysis was kept in the research. They were all proved to be effective to provide insight into the dynamic process of self identity constructing.     

Social‐Psychological Theories and Adolescent Health Risk Behavior

This paper reviews several psychosocial theories that have been applied to the study of adolescent health behavior. Some of these theories have existed for several decades and, though not originally intended for this purpose, have proven quite useful in predicting and explaining many different types of health‐relevant behaviors. During the last 10–15 years, however, there has been a significant increase in the application of social psychological theories to the examination of what is increasingly being seen as a social‐psychological phenomenon: health risk behavior among adolescents. This interest has been prompted, in part, by an appreciation of the value of dual‐processing principles in explaining these behaviors, and, in particular, a recognition that much adolescent health risk behavior: a) is not always planful or premeditated, and b) involves both heuristic and analytic processing. The paper includes discussion of how dual‐processing principles and social‐psychological theories can inform intervention efforts.     

University STEM instructors with stronger failure-as-debilitating mindsets are perceived to engage in fewer mastery-oriented teaching Practices by their students: An exploratory study

Social Psychology of Education - The present study builds on and adds to a growing body of literature suggesting that teachers’ mindsets predict students’ classroom experiences. We...     

A Class of Distribution-Free Models for Longitudinal Mediation Analysis

Mediation analysis constitutes an important part of treatment study to identify the mechanisms by which an intervention achieves its effect. Structural equation model (SEM) is a popular framework for modeling such causal relationship. However, current methods impose various restrictions on the study designs and data distributions, limiting the utility of the information they provide in real study applications. In particular, in longitudinal studies missing data is commonly addressed under the assumption of missing at random (MAR), where current methods are unable to handle such missing data if parametric assumptions are violated. In this paper, we propose a new, robust approach to address the limitations of current SEM within the context of longitudinal mediation analysis by utilizing a class of functional response models (FRM). Being distribution-free, the FRM-based approach does not impose any parametric assumption on data distributions. In addition, by extending the inverse probability weighted (IPW) estimates to the current context, the FRM-based SEM provides valid inference for longitudinal mediation analysis under the two most popular missing data mechanisms; missing completely at random (MCAR) and missing at random (MAR). We illustrate the approach with both real and simulated data.     

Why does guessing incorrectly enhance,rather than impair,retention?

The finding that trying, and failing, to predict the upcoming to-be-remembered response to a given cue can enhance later recall of that response, relative to studying the intact cue–response pair, is surprising, especially given that the standard paradigm (e.g., Kornell, Hays, & Bjork, 2009) involves allocating what would otherwise be study time to generating an error. In three experiments, we sought to eliminate two potential heuristics that participants might use to aid recall of correct responses on the final test and to explore the effects of interference both at an immediate and at a delayed test. In Experiment 1, by intermixing strongly associated to-be-remembered pairs with weakly associated pairs, we eliminated a potential heuristic participants can use on the final test in the standard version of the paradigm—namely, that really strong associates are incorrect responses. In Experiment 2, by rigging half of the participants’ responses to be correct, we eliminated another potential heuristic—namely, that one’s initial guesses are virtually always wrong. In Experiment 3, we examined whether participants’ ability to remember—and discriminate between—their incorrect guesses and correct responses would be lost after a 48-h delay, when source memory should be reduced. Across all experiments, we continued to find a robust benefit of trying to guess to-be-learned responses, even when incorrect, versus studying intact cue–response pairs. The benefits of making incorrect guesses are not an artifact of the paradigm, nor are they limited to short retention intervals.