Bridging psychology and biology: the analysis of individuals in groups.

Biological systems are particularly prone to variation, and the authors argue that such variation must be regarded as important data in its own right. The authors describe a method in which individual differences are studied within the framework of a general theory of the population as a whole and illustrate how this method can be used to address three types of issues: the nature of the mechanisms that give rise to a specific ability, such as mental imagery; the role of psychological or biological mediators of environmental challenges, such as the biological bases for differences in dispositional mood; and the existence of processes that have nonadditive effects with behavioral and physiological variables, such as factors that modulate the response to stress and its effects on the immune response. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Sex Differences and Individual Differences in Cognitive Performance and Their Relationship to Endogenous Gonadal Hormones and Gonadotropins.

Sexually dimorphic cognitive performance in men (n=42) and women (n=42) was related to testosterone, estradiol, progesterone, luteinizing hormone, follicle-stimulating hormone, and sex hormone binding globulin, measured in 10-ml blood samples collected between 0900 and 1030 and, among women, during the follicular phase of the menstrual cycle. Significant sex differences favored men on spatial tasks (Mental Rotation and Judgment of Line Orientation) and on an inhibition task and favored women on a verbal task (category fluency). However, there were no significant relationships between any of the hormones and cognitive performance, suggesting that there are few, if any, consistent, substantial relationships between endogenous, nonfluctuating levels of gonadal hormones or gonadotropins and these cognitive abilities in men or women. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Developmental Dynamics of Math Performance From Preschool to Grade 2.

This study investigated the developmental dynamics of mathematical performance during children's transition from preschool to Grade 2 and the cognitive antecedents of this development. 194 Finnish children were examined 6 times according to their math performance, twice during each year across a 3-year period. Cognitive antecedents, that is, counting ability, visual attention, metacognitive knowledge, and listening comprehension, were tested at the first measurement point. The results indicated that math performance showed high stability and increasing variance over time. Moreover, the growth of math competence was faster among those who entered preschool with an already high level of mathematical skills. The initial level of math performance, as well as its growth, was best predicted by counting ability. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Stereotype Threat and Group Differences in Test Performance: A Question of Measurement Invariance.

Studies into the effects of stereotype threat (ST) on test performance have shed new light on race and sex differences in achievement and intelligence test scores. In this article, the authors relate ST theory to the psychometric concept of measurement invariance and show that ST effects may be viewed as a source of measurement bias. As such, ST effects are detectable by means of multigroup confirmatory factor analysis. This enables research into the generalizability of ST effects to real-life or high-stakes testing. The modeling approach is described in detail and applied to 3 experiments in which the amount of ST for minorities and women was manipulated. Results indicate that ST results in measurement bias of intelligence and mathematics tests. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

The role of mindfulness in predicting individual performance.

Mindfulness refers to an individual difference variable regarding the degree to which a person is in the present moment (K. W. Brown & R. M. Ryan, 2003). Despite a growing interest in the benefits of mindfulness in health and clinical outcomes, little research has explored whether mindfulness relates to individual performance. The authors examined whether mindfulness was related to performance among a group of MBA students (N = 149). The results show that mindfulness interacted with gender to predict performance. Specifically, the positive association between mindfulness and performance was stronger for women than for men. Implications and future directions are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Children's sleep and cognitive performance: A cross-domain analysis of change over time.

Relations between changes in children's cognitive performance and changes in sleep problems were examined over a 3-year period, and family socioeconomic status, child race/ethnicity, and gender were assessed as moderators of these associations. Participants were 250 second- and third-grade (8–9 years old at Time 1) boys and girls. At each assessment, children's cognitive performance (Verbal Comprehension, Decision Speed) was measured using the Woodcock-Johnson III Tests of Cognitive Abilities, and sleep problems (Sleepiness, Sleep/Wake Problems) were collected via self-report. Individual growth models revealed that children who reported increases in Sleepiness exhibited little growth in Verbal Comprehension over time compared with their peers who reported decreases in Sleepiness, resulting in a nearly 11-point cognitive deficit by the end of the study. These associations were not found for Sleep/Wake Problems or Decision Speed. Child race/ethnicity and gender moderated these associations, with Sleepiness serving as a vulnerability factor for poor cognitive outcomes, especially among African American children and girls. Differences in cognitive performance for children with high and low Sleepiness trajectories ranged from 16 to 19 points for African American children and from 11 to 19 points for girls. Results build substantially on existing literature examining associations between sleep and cognitive functioning in children and are the first to demonstrate that children's sleep trajectories over 3 waves were associated with changes in their cognitive performance over time. (PsycINFO Database Record (c) 2011 APA, all rights reserved)     

Using theory to evaluate personality and job-performance relations: A socioanalytic perspective.

The authors used socioanalytic theory to understand individual differences in people's performance at work. Specifically, if predictors and criteria are aligned by using theory, then the meta-analytic validity of personality measures exceeds that of atheoretical approaches. As performance assessment moved from general to specific job criteria, all Big Five personality dimensions more precisely predicted relevant criterion variables, with estimated true validities of .43 (Emotional Stability), .35 (Extraversion-Ambition), .34 (Agreeableness), .36 (Conscientiousness), and .34 (Intellect-Openness to Experience). (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Using SAT-Grade and Ability-Job Performance Relationships to Test Predictions Derived From Stereotype Threat Theory.

To examine the generalizability of stereotype threat theory findings from laboratory to applied settings, the authors developed models of the pattern of relationships between cognitive test scores and outcome criteria that would be expected if the test scores of women and minority group members were affected by stereotype threat. Two large data sets were used to test these models, one in an education setting examining SAT-grade relationships by race and gender and the other in a military job setting examining Armed Services Vocational Aptitude Battery-job performance relationships by race. Findings were not supportive of the predictions arising from stereotype threat theory, suggesting caution in positing threat as a key determinant of subgroup mean test score differences in applied settings. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Deep-level composition variables as predictors of team performance: A meta-analysis.

This study sought to unify the team composition literature by using meta-analytic techniques to estimate the relationships between specified deep-level team composition variables (i.e., personality factors, values, abilities) and team performance. The strength of the team composition variable and team performance relationships was moderated by the study setting (lab or field) and the operationalization of the team composition variable. In lab settings, team minimum and maximum general mental ability and team mean emotional intelligence were related to team performance. Only negligible effects were observed in lab settings for the personality factor and team performance relationships, as well as the value and team performance relationships. In contrast, team minimum agreeableness and team mean conscientiousness, openness to experience, collectivism, and preference for teamwork emerged as strong predictors of team performance in field studies. Results can be used to effectively compose teams in organizations and guide future team composition research. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Is There a General Factor in Ratings of Job Performance? A Meta-Analytic Framework for Disentangling Substantive and Error Influences.

A database integrating 90 years of empirical studies reporting intercorrelations among rated job performance dimensions was used to test the hypothesis of a general factor in job performance. After controlling for halo error and 3 other sources of measurement error, there remained a general factor in job performance ratings at the construct level accounting for 60% of total variance. Construct-level correlations among rated dimensions of job performance were substantially inflated by halo for both supervisory (33%) and peer (63%) intrarater correlations. These findings have important implications for the measurement of job performance and for theories of job performance. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Aged and Adult Rats Compared in Acquisition and Extinction of Escape From the Water Maze: Focus on Individual Differences.

Individual differences in water maze and open-field performance of aged and adult rats were compared in a cross-sectional study. Three- and 24-month-old rats were classified into superior, moderate, and inferior groups on the basis of escape latencies during hidden platform acquisition and were compared regarding water maze acquisition and extinction, and open-field behavior. Unexpectedly, subgroup differences were invariant across age: The inferior and superior maze learners differed in (a) thigmotactic swimming during water maze acquisition and extinction and (b) open-field rearings. Thus, although aging has a detrimental effect on water maze acquisition and extinction, the degree of impairment might be partly determined by individual novelty-induced rearing activity and thigmotactic swimming at adult ages. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Development of Individual Differences in Reading: Results From Longitudinal Studies in English and Finnish.

The authors examined individual differences in reading development in English and Finnish. English-speaking Canadian children were assessed once per year in Grades 1-5, and Finnish children were assessed twice per year in Grades 1-2. Results from latent growth curve and simplex analyses showed that initial status was generally negatively associated with subsequent growth and that, although stable, individual differences were more likely to significantly decrease than to increase across the measurement points. Growth mixture models identified multiple groups of children whose reading development followed distinct patterns. The results indicate that it is possible for educational systems to significantly reduce individual differences in basic reading skills during early reading development. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

From marianthal to latent growth mixture modeling: A return to the exploration of individual differences in response to unemployment.

Job-loss is a rapidly growing concern as we witness the greatest and most rapid economic downturn in a century. The negative psychological effect of unemployment has increasingly garnered attention. Previous literature has offered a formidable prognosis, stating that in response to job-loss, people typically follow a pattern of rapid decline in life satisfaction and never return to preunemployment levels. In this paper, we attempt to search for individual differences in response to job-loss using Latent Growth Mixture Modeling (LGMM) framework. By building homogeneous trajectories within a prospective design from 3 years before to 4 years after job-loss, we find that the majority of individuals (82%) demonstrate no long-term effects on life satisfaction in response to unemployment. We also examine the roll of larger market forces on levels of life satisfaction during and around the event of job-loss. Using a correlation model, demonstrated that life satisfaction is positively influenced by the regional unemployment rate. Clark (2003) argues that people report higher well-being when they lose their job if those in proximity to them are also becoming unemployed. Using the national and local unemployment rate in a regression model nested in the Latent Growth Model, we found that a social comparison effect is present immediately before unemployment but not once individuals became unemployed. This implies that people reference national and local employment trends in an attempt to anticipate their own course of employment rather than referencing those trends after job-loss. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Modes of executive control in sequence learning: From stimulus-based to plan-based control.

The authors argue that human sequential learning is often but not always characterized by a shift from stimulus- to plan-based action control. To diagnose this shift, they manipulated the frequency of 1st-order transitions in a repeated manual left-right sequence, assuming that performance is sensitive to frequency-induced biases under stimulus- but not plan-based control. Indeed, frequency biases tended to disappear with practice, but only for explicit learners. This tendency was facilitated by visual-verbal target stimuli, response-contingent sounds, and intentional instructions and hampered by auditory (but not visual) noise. Findings are interpreted within an event-coding model of action control, which holds that plans for sequences of discrete actions are coded phonetically, integrating order and relative timing. The model distinguishes between plan acquisition, linked to explicit knowledge, and plan execution, linked to the action control mode. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Self-Regulation: From Goal Orientation to Job Performance.

The authors investigated the effects on job performance of 3 forms of goal orientation and 4 self-regulation (SR) tactics. In a longitudinal field study with salespeople, learning and performance-prove goal orientation predicted subsequent sales performance, whereas performance-avoid goal orientation negatively predicted sales performance. The SR tactics functioned as mediating variables between learning and performance-prove goal orientations and performance. Social competence and proactive behavior directly and positively predicted sales performance, and emotional control negatively predicted performance. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

The role of general systems and information theory in multi-factor individuality theory.

Concepts and principles from general systems and information theory are brought to bear on individuality theory. J. G. Miller's conceptual framework for the organism as a general system is singled out for special consideration in relation to the organism as viewed by individuality theory. Individuality theory involves mapping out the dimensions of individual differences in diverse domains (abilities, temperament, styles, values, interests, etc.), organizing the within domain and between-domain relationships into an integrated hierarchical structure, and attempting to explain the interaction and integration of the separate components. Systems and information theory are particularly potent in aiding the accomplishment of the latter two aspects. Thus, factor-identified dimensions of individual differences are viewed as information processors or mediators. Information flow occurs both within and between the sensory, cognitive, affective, style, evaluative, and motor systems, and the integration of the organism depends upon such systemic properties as hierarchical structure, hierarchy of values, steady states, and systems interactions. In this way an attempt is made to bridge three theoretical perspectives, cross-fertilizations of which may produce a vigorous offspring. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Expert performance in SCRABBLE: Implications for the study of the structure and acquisition of complex skills.

Applied psychologists have long been interested in examining expert performance in complex cognitive domains. In the present article, we report the results from a study of expert cognitive skill in which elements from two historically distinct research paradigms are incorporated--the individual differences tradition and the expert-performance approach. Forty tournament-rated SCRABBLE players (20 elite, 20 average) and 40 unrated novice players completed a battery of domain-representative laboratory tasks and standardized verbal ability tests. The analyses revealed that elite- and average-level rated players only significantly differed from each other on tasks representative of SCRABBLE performance. Furthermore, domain-relevant practice mediated the effects of SCRABBLE tournament ratings on representative task performance, suggesting that SCRABBLE players can acquire some of the knowledge necessary for success at the highest levels of competition by engaging in activities deliberately designed to maximize adaptation to SCRABBLE-specific task constraints. We discuss the potential importance of our results in the context of continuing efforts to capture and explain superior performance across intellectual domains. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

A Simple Effect Size Indicator for Two-Group Comparisons? A Comment on requivalent.

R. Rosenthal and D. B. Rubin (2003) proposed an effect size, requivalent, to be used when (a) only sample size and p values are known for a study, (b) there are no generally accepted effect size indicators, or (c) sample sizes are so small or the data so non-normal that the directly computed effect sizes would be more misleading than the simple effect size. The limitations of their proposal, however, are many, and much more serious than the authors suggested, and should be carefully considered before this effect size is applied, as well as in developing other effect sizes using similar methods. (PsycINFO Database Record (c) 2010 APA, all rights reserved)