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Sample records for modeling individual differences

  1. Modelling individual difference in visual categorization.

    Science.gov (United States)

    Shen, Jianhong; Palmeri, Thomas J

    Recent years has seen growing interest in understanding, characterizing, and explaining individual differences in visual cognition. We focus here on individual differences in visual categorization. Categorization is the fundamental visual ability to group different objects together as the same kind of thing. Research on visual categorization and category learning has been significantly informed by computational modeling, so our review will focus both on how formal models of visual categorization have captured individual differences and how individual difference have informed the development of formal models. We first examine the potential sources of individual differences in leading models of visual categorization, providing a brief review of a range of different models. We then describe several examples of how computational models have captured individual differences in visual categorization. This review also provides a bit of an historical perspective, starting with models that predicted no individual differences, to those that captured group differences, to those that predict true individual differences, and to more recent hierarchical approaches that can simultaneously capture both group and individual differences in visual categorization. Via this selective review, we see how considerations of individual differences can lead to important theoretical insights into how people visually categorize objects in the world around them. We also consider new directions for work examining individual differences in visual categorization.

  2. Mental Models, Magical Thinking, And Individual Differences

    Directory of Open Access Journals (Sweden)

    Phil Turner

    2009-01-01

    Full Text Available Broadly, there are two mutually exclusive accounts of how people (non-specialist users reason about and conceptualize interactive technology. The first is based on classical cognitive psychology and is characterized by the term mental model. The second, drawing on concepts from social cognition, observes that people often anthropomorphize technology. We argue that people are able to exhibit both of these quite different styles of cognition, which Baron-Cohen has described as systemizing and empathizing. The former is associated with the drive to analyze, explore, and construct a system, whereas the latter is the ability to spontaneously tune into another’s thoughts and feelings. The propensity to systemize might give rise to a mental model, while the empathizing tendency might tend to anthropomorphize technology. We present an empirical study that lends support for the above position.

  3. Individual differences in emotion word processing: A diffusion model analysis.

    Science.gov (United States)

    Mueller, Christina J; Kuchinke, Lars

    2016-06-01

    The exploratory study investigated individual differences in implicit processing of emotional words in a lexical decision task. A processing advantage for positive words was observed, and differences between happy and fear-related words in response times were predicted by individual differences in specific variables of emotion processing: Whereas more pronounced goal-directed behavior was related to a specific slowdown in processing of fear-related words, the rate of spontaneous eye blinks (indexing brain dopamine levels) was associated with a processing advantage of happy words. Estimating diffusion model parameters revealed that the drift rate (rate of information accumulation) captures unique variance of processing differences between happy and fear-related words, with highest drift rates observed for happy words. Overall emotion recognition ability predicted individual differences in drift rates between happy and fear-related words. The findings emphasize that a significant amount of variance in emotion processing is explained by individual differences in behavioral data.

  4. A model of individual differences in learning air traffic control

    NARCIS (Netherlands)

    Taatgen, NA; Altmann, EM; Cleeremans, A; Schunn, CD; Gray, WD

    2001-01-01

    Individual differences in skill acquisition are influenced by several architectural factors. According to Ackerman's theory, general intelligence, speed of proceduralization and psychomotor speed influence different stages of skill acquisition. Ackerman tested this theory by correlating performance

  5. Dosha brain-types: A neural model of individual differences.

    Science.gov (United States)

    Travis, Frederick T; Wallace, Robert Keith

    2015-01-01

    This paper explores brain patterns associated with the three categories of regulatory principles of the body, mind, and behavior in Ayurveda, called Vata, Pitta, and Kapha dosha. A growing body of research has reported patterns of blood chemistry, genetic expression, physiological states, and chronic diseases associated with each dosha type. Since metabolic and growth factors are controlled by the nervous system, each dosha type should be associated with patterns of functioning of six major areas of the nervous system: The prefrontal cortex, the reticular activating system, the autonomic nervous system, the enteric nervous system, the limbic system, and the hypothalamus. For instance, the prefrontal cortex, which includes the anterior cingulate, ventral medial, and the dorsal lateral cortices, would exhibit a high range of functioning in the Vata brain-type leading to the possibility of being easily overstimulated. The Vata brain-type performs activity quickly. Learns quickly and forgets quickly. Their fast mind gives them an edge in creative problem solving. The Pitta brain-type reacts strongly to all challenges leading to purposeful and resolute actions. They never give up and are very dynamic and goal oriented. The Kapha brain-type is slow and steady leading to methodical thinking and action. They prefer routine and needs stimulation to get going. A model of dosha brain-types could provide a physiological foundation to understand individual differences. This model could help individualize treatment modalities to address different mental and physical dysfunctions. It also could explain differences in behavior seen in clinical as well as in normal populations.

  6. Dosha brain-types: A neural model of individual differences

    Directory of Open Access Journals (Sweden)

    Frederick T Travis

    2015-01-01

    Full Text Available This paper explores brain patterns associated with the three categories of regulatory principles of the body, mind, and behavior in Ayurveda, called Vata, Pitta, and Kapha dosha. A growing body of research has reported patterns of blood chemistry, genetic expression, physiological states, and chronic diseases associated with each dosha type. Since metabolic and growth factors are controlled by the nervous system, each dosha type should be associated with patterns of functioning of six major areas of the nervous system: The prefrontal cortex, the reticular activating system, the autonomic nervous system, the enteric nervous system, the limbic system, and the hypothalamus. For instance, the prefrontal cortex, which includes the anterior cingulate, ventral medial, and the dorsal lateral cortices, would exhibit a high range of functioning in the Vata brain-type leading to the possibility of being easily overstimulated. The Vata brain-type performs activity quickly. Learns quickly and forgets quickly. Their fast mind gives them an edge in creative problem solving. The Pitta brain-type reacts strongly to all challenges leading to purposeful and resolute actions. They never give up and are very dynamic and goal oriented. The Kapha brain-type is slow and steady leading to methodical thinking and action. They prefer routine and needs stimulation to get going. A model of dosha brain-types could provide a physiological foundation to understand individual differences. This model could help individualize treatment modalities to address different mental and physical dysfunctions. It also could explain differences in behavior seen in clinical as well as in normal populations.

  7. Investigating Individual Differences in Toddler Search with Mixture Models

    Science.gov (United States)

    Berthier, Neil E.; Boucher, Kelsea; Weisner, Nina

    2015-01-01

    Children's performance on cognitive tasks is often described in categorical terms in that a child is described as either passing or failing a test, or knowing or not knowing some concept. We used binomial mixture models to determine whether individual children could be classified as passing or failing two search tasks, the DeLoache model room…

  8. Biomechanical Evaluations of Hip Fracture Using Finite Element Model that Models Individual Differences of Femur

    OpenAIRE

    田中, 英一; TANAKA, Eiichi; 山本, 創太; YAMAMOTO, Sota; 坂本, 誠二; SAKAMOTO, Seiji; 中西, 孝文; NAKANISHI, Takafumi; 原田, 敦; HARADA, Atsushi; 水野, 雅士; MIZUNO, Masashi

    2004-01-01

    This paper is concerned with an individual finite element modeling system for femur and biomechanical evaluations of the influences of loading conditions, bone shape and bone density on risks of hip fracture. Firstly, a method to construct an individual finite element model by morphological parameters that represent femoral shapes was developed. Using the models with different shapes constructed by this method, the effects of fall direction, posture of upper body, femur shape and bone density...

  9. Computational Models of Individual Differences in Working Memory Capacity

    National Research Council Canada - National Science Library

    Frankel, Gerald

    2002-01-01

    ...) because the attack in Al alloys seems to transition into IGC as it grows. A statistical model to describe the effect of microstructure on the IG path length and thus penetration rate was developed...

  10. Using decision models to enhance investigations of individual differences in cognitive neuroscience

    Directory of Open Access Journals (Sweden)

    Corey N White

    2016-02-01

    Full Text Available There is great interest in relating individual differences in cognitive processing to activation of neural systems. The general process involves relating measures of task performance like reaction times or accuracy to brain activity to identify individual differences in neural processing. One limitation of this approach is that measures like reaction times can be affected by multiple components of processing. For instance, some individuals might have higher accuracy in a memory task because they respond more cautiously, not because they have better memory. Computational models of decision making, like the drift-diffusion model and the linear ballistic accumulator model, provide a potential solution to this problem. They can be fitted to data from individual participants to disentangle the effects of the different processes driving behavior. In this sense the models can provide cleaner measures of the processes of interest, and enhance our understanding of how neural activity varies across individuals or populations. The advantages of this model-based approach to investigating individual differences in neural activity are discussed with recent examples of how this method can improve our understanding of the brain-behavior relationship.

  11. Probabilistic Inference: Task Dependency and Individual Differences of Probability Weighting Revealed by Hierarchical Bayesian Modeling.

    Science.gov (United States)

    Boos, Moritz; Seer, Caroline; Lange, Florian; Kopp, Bruno

    2016-01-01

    Cognitive determinants of probabilistic inference were examined using hierarchical Bayesian modeling techniques. A classic urn-ball paradigm served as experimental strategy, involving a factorial two (prior probabilities) by two (likelihoods) design. Five computational models of cognitive processes were compared with the observed behavior. Parameter-free Bayesian posterior probabilities and parameter-free base rate neglect provided inadequate models of probabilistic inference. The introduction of distorted subjective probabilities yielded more robust and generalizable results. A general class of (inverted) S-shaped probability weighting functions had been proposed; however, the possibility of large differences in probability distortions not only across experimental conditions, but also across individuals, seems critical for the model's success. It also seems advantageous to consider individual differences in parameters of probability weighting as being sampled from weakly informative prior distributions of individual parameter values. Thus, the results from hierarchical Bayesian modeling converge with previous results in revealing that probability weighting parameters show considerable task dependency and individual differences. Methodologically, this work exemplifies the usefulness of hierarchical Bayesian modeling techniques for cognitive psychology. Theoretically, human probabilistic inference might be best described as the application of individualized strategic policies for Bayesian belief revision.

  12. Developing an agent-based model on how different individuals solve complex problems

    Directory of Open Access Journals (Sweden)

    Ipek Bozkurt

    2015-01-01

    Full Text Available Purpose: Research that focuses on the emotional, mental, behavioral and cognitive capabilities of individuals has been abundant within disciplines such as psychology, sociology, and anthropology, among others. However, when facing complex problems, a new perspective to understand individuals is necessary. The main purpose of this paper is to develop an agent-based model and simulation to gain understanding on the decision-making and problem-solving abilities of individuals. Design/Methodology/approach: The micro-level analysis modeling and simulation paradigm Agent-Based Modeling Through the use of Agent-Based Modeling, insight is gained on how different individuals with different profiles deal with complex problems. Using previous literature from different bodies of knowledge, established theories and certain assumptions as input parameters, a model is built and executed through a computer simulation. Findings: The results indicate that individuals with certain profiles have better capabilities to deal with complex problems. Moderate profiles could solve the entire complex problem, whereas profiles within extreme conditions could not. This indicates that having a strong predisposition is not the ideal way when approaching complex problems, and there should always be a component from the other perspective. The probability that an individual may use these capabilities provided by the opposite predisposition provides to be a useful option. Originality/value: The originality of the present research stems from how individuals are profiled, and the model and simulation that is built to understand how they solve complex problems. The development of the agent-based model adds value to the existing body of knowledge within both social sciences, and modeling and simulation.

  13. Probabilistic inference: Task dependency and individual differences of probability weighting revealed by hierarchical Bayesian modelling

    Directory of Open Access Journals (Sweden)

    Moritz eBoos

    2016-05-01

    Full Text Available Cognitive determinants of probabilistic inference were examined using hierarchical Bayesian modelling techniques. A classic urn-ball paradigm served as experimental strategy, involving a factorial two (prior probabilities by two (likelihoods design. Five computational models of cognitive processes were compared with the observed behaviour. Parameter-free Bayesian posterior probabilities and parameter-free base rate neglect provided inadequate models of probabilistic inference. The introduction of distorted subjective probabilities yielded more robust and generalizable results. A general class of (inverted S-shaped probability weighting functions had been proposed; however, the possibility of large differences in probability distortions not only across experimental conditions, but also across individuals, seems critical for the model’s success. It also seems advantageous to consider individual differences in parameters of probability weighting as being sampled from weakly informative prior distributions of individual parameter values. Thus, the results from hierarchical Bayesian modelling converge with previous results in revealing that probability weighting parameters show considerable task dependency and individual differences. Methodologically, this work exemplifies the usefulness of hierarchical Bayesian modelling techniques for cognitive psychology. Theoretically, human probabilistic inference might be best described as the application of individualized strategic policies for Bayesian belief revision.

  14. Risk, individual differences, and environment: an Agent-Based Modeling approach to sexual risk-taking.

    Science.gov (United States)

    Nagoski, Emily; Janssen, Erick; Lohrmann, David; Nichols, Eric

    2012-08-01

    Risky sexual behaviors, including the decision to have unprotected sex, result from interactions between individuals and their environment. The current study explored the use of Agent-Based Modeling (ABM)-a methodological approach in which computer-generated artificial societies simulate human sexual networks-to assess the influence of heterogeneity of sexual motivation on the risk of contracting HIV. The models successfully simulated some characteristics of human sexual systems, such as the relationship between individual differences in sexual motivation (sexual excitation and inhibition) and sexual risk, but failed to reproduce the scale-free distribution of number of partners observed in the real world. ABM has the potential to inform intervention strategies that target the interaction between an individual and his or her social environment.

  15. Cognitive Style: Individual Differences.

    Science.gov (United States)

    Saracho, Olivia N.

    1989-01-01

    A literature review describes several dimensions of cognitive styles in an effort to illustrate individual stylistic differences. Discusses the field dependence-independence dimension, taking into account age, sex, and cultural differences. Suggests that cognitive style theory needs to be structured in a broader theoretical framework. (NH)

  16. Information retrieval and individual differences

    Directory of Open Access Journals (Sweden)

    Polona Vilar

    2008-01-01

    Full Text Available The paper presents individual differences, which are found in studies of information retrieval with emphasis on models of personality traits, cognitive and learning styles. It pays special attention to those models which are most often included in studies of information behaviour,information seeking,perceptions of IR systems, etc., but also brings forward some models which have not yet been included in such studies. Additionally, the relationship between different individual characteristics and individual’s chosen profession or academic area is discussed. In this context,the paper presents how investigation of individual differences can be useful in the design of IR systems.

  17. Individual differences in behavioural plasticities.

    Science.gov (United States)

    Stamps, Judy A

    2016-05-01

    plasticities observed at a given age. Several authors have predicted correlations across individuals between different types of behavioural plasticities, i.e. that some individuals will be generally more plastic than others. However, empirical support for most of these predictions, including indirect evidence from studies of relationships between personality traits and plasticities, is currently sparse and equivocal. The final section of this review suggests how an appreciation of the similarities and differences between different types of behavioural plasticities may help theoreticians formulate testable models to explain the evolution of individual differences in behavioural plasticities and the evolutionary and ecological consequences of individual differences in behavioural plasticities. © 2015 Cambridge Philosophical Society.

  18. Behavioral facilitation: a cognitive model of individual differences in approach motivation.

    Science.gov (United States)

    Robinson, Michael D; Meier, Brian P; Tamir, Maya; Wilkowski, Benjamin M; Ode, Scott

    2009-02-01

    Approach motivation consists of the active, engaged pursuit of one's goals. The purpose of the present three studies (N = 258) was to examine whether approach motivation could be cognitively modeled, thereby providing process-based insights into personality functioning. Behavioral facilitation was assessed in terms of faster (or facilitated) reaction time with practice. As hypothesized, such tendencies predicted higher levels of approach motivation, higher levels of positive affect, and lower levels of depressive symptoms and did so across cognitive, behavioral, self-reported, and peer-reported outcomes. Tendencies toward behavioral facilitation, on the other hand, did not correlate with self-reported traits (Study 1) and did not predict avoidance motivation or negative affect (all studies). The results indicate a systematic relationship between behavioral facilitation in cognitive tasks and approach motivation in daily life. Results are discussed in terms of the benefits of modeling the cognitive processes hypothesized to underlie individual differences motivation, affect, and depression. (c) 2009 APA, all rights reserved

  19. Individual differences in emotion processing: how similar are diffusion model parameters across tasks?

    Science.gov (United States)

    Mueller, Christina J; White, Corey N; Kuchinke, Lars

    2017-11-27

    The goal of this study was to replicate findings of diffusion model parameters capturing emotion effects in a lexical decision task and investigating whether these findings extend to other tasks of implicit emotion processing. Additionally, we were interested in the stability of diffusion model parameters across emotional stimuli and tasks for individual subjects. Responses to words in a lexical decision task were compared with responses to faces in a gender categorization task for stimuli of the emotion categories: happy, neutral and fear. Main effects of emotion as well as stability of emerging response style patterns as evident in diffusion model parameters across these tasks were analyzed. Based on earlier findings, drift rates were assumed to be more similar in response to stimuli of the same emotion category compared to stimuli of a different emotion category. Results showed that emotion effects of the tasks differed with a processing advantage for happy followed by neutral and fear-related words in the lexical decision task and a processing advantage for neutral followed by happy and fearful faces in the gender categorization task. Both emotion effects were captured in estimated drift rate parameters-and in case of the lexical decision task also in the non-decision time parameters. A principal component analysis showed that contrary to our hypothesis drift rates were more similar within a specific task context than within a specific emotion category. Individual response patterns of subjects across tasks were evident in significant correlations regarding diffusion model parameters including response styles, non-decision times and information accumulation.

  20. Modeling individual differences in text reading fluency: a different pattern of predictors for typically developing and dyslexic readers

    Directory of Open Access Journals (Sweden)

    Pierluigi eZoccolotti

    2014-11-01

    Full Text Available This study was aimed at predicting individual differences in text reading fluency. The basic proposal included two factors, i.e., the ability to decode letter strings (measured by discrete pseudo-word reading and integration of the various sub-components involved in reading (measured by Rapid Automatized Naming, RAN. Subsequently, a third factor was added to the model, i.e., naming of discrete digits. In order to use homogeneous measures, all contributing variables considered the entire processing of the item, including pronunciation time. The model, which was based on commonality analysis, was applied to data from a group of 43 typically developing readers (11- to 13-year-olds and a group of 25 chronologically matched dyslexic children. In typically developing readers, both orthographic decoding and integration of reading sub-components contributed significantly to the overall prediction of text reading fluency. The model prediction was higher (from ca. 37% to 52% of the explained variance when we included the naming of discrete digits variable, which had a suppressive effect on pseudo-word reading. In the dyslexic readers, the variance explained by the two-factor model was high (69% and did not change when the third factor was added. The lack of a suppression effect was likely due to the prominent individual differences in poor orthographic decoding of the dyslexic children. Analyses on data from both groups of children were replicated by using patches of colours as stimuli (both in the RAN task and in the discrete naming task obtaining similar results. We conclude that it is possible to predict much of the variance in text-reading fluency using basic processes, such as orthographic decoding and integration of reading sub-components, even without taking into consideration higher-order linguistic factors such as lexical, semantic and contextual abilities. The approach validity of using proximal vs distal causes to predict reading fluency is

  1. Male Wistar rats show individual differences in an animal model of conformity.

    Science.gov (United States)

    Jolles, Jolle W; de Visser, Leonie; van den Bos, Ruud

    2011-09-01

    Conformity refers to the act of changing one's behaviour to match that of others. Recent studies in humans have shown that individual differences exist in conformity and that these differences are related to differences in neuronal activity. To understand the neuronal mechanisms in more detail, animal tests to assess conformity are needed. Here, we used a test of conformity in rats that has previously been evaluated in female, but not male, rats and assessed the nature of individual differences in conformity. Male Wistar rats were given the opportunity to learn that two diets differed in palatability. They were subsequently exposed to a demonstrator that had consumed the less palatable food. Thereafter, they were exposed to the same diets again. Just like female rats, male rats decreased their preference for the more palatable food after interaction with demonstrator rats that had eaten the less palatable food. Individual differences existed for this shift, which were only weakly related to an interaction between their own initial preference and the amount consumed by the demonstrator rat. The data show that this conformity test in rats is a promising tool to study the neurobiology of conformity.

  2. Modeling the Role of Networks and Individual Differences in Inter-Group Violence.

    Directory of Open Access Journals (Sweden)

    Alexander Isakov

    Full Text Available There is significant heterogeneity within and between populations in their propensity to engage in conflict. Most research has neglected the role of within-group effects in social networks in contributing to between-group violence and focused instead on the precursors and consequences of violence, or on the role of between-group ties. Here, we explore the role of individual variation and of network structure within a population in promoting and inhibiting group violence towards other populations. Motivated by ethnographic observations of collective behavior in a small-scale society, we describe a model with differentiated roles for individuals embedded within friendship networks. Using a simple model based on voting-like dynamics, we explore several strategies for influencing group-level behavior. When we consider changing population level attitude changes and introducing control nodes separately, we find that a particularly effective control strategy relies on exploiting network degree. We also suggest refinements to our model such as tracking fine-grained information spread dynamics that can lead to further enrichment in using evolutionary game theory models for sociological phenomena.

  3. Modeling Bivariate Change in Individual Differences: Prospective Associations Between Personality and Life Satisfaction.

    Science.gov (United States)

    Hounkpatin, Hilda Osafo; Boyce, Christopher J; Dunn, Graham; Wood, Alex M

    2017-09-18

    A number of structural equation models have been developed to examine change in 1 variable or the longitudinal association between 2 variables. The most common of these are the latent growth model, the autoregressive cross-lagged model, the autoregressive latent trajectory model, and the latent change score model. The authors first overview each of these models through evaluating their different assumptions surrounding the nature of change and how these assumptions may result in different data interpretations. They then, to elucidate these issues in an empirical example, examine the longitudinal association between personality traits and life satisfaction. In a representative Dutch sample (N = 8,320), with participants providing data on both personality and life satisfaction measures every 2 years over an 8-year period, the authors reproduce findings from previous research. However, some of the structural equation models overviewed have not previously been applied to the personality-life satisfaction relation. The extended empirical examination suggests intraindividual changes in life satisfaction predict subsequent intraindividual changes in personality traits. The availability of data sets with 3 or more assessment waves allows the application of more advanced structural equation models such as the autoregressive latent trajectory or the extended latent change score model, which accounts for the complex dynamic nature of change processes and allows stronger inferences on the nature of the association between variables. However, the choice of model should be determined by theories of change processes in the variables being studied. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

  4. Individual differences in boys' and girls' timing and tempo of puberty: modeling development with nonlinear growth models.

    Science.gov (United States)

    Marceau, Kristine; Ram, Nilam; Houts, Renate M; Grimm, Kevin J; Susman, Elizabeth J

    2011-09-01

    Pubertal development is a nonlinear process progressing from prepubescent beginnings through biological, physical, and psychological changes to full sexual maturity. To tether theoretical concepts of puberty with sophisticated longitudinal, analytical models capable of articulating pubertal development more accurately, we used nonlinear mixed-effects models to describe both the timing and tempo of pubertal development in the sample of 364 White boys and 373 White girls measured across 6 years as part of the National Institute of Child Health and Human Development Study of Early Child Care and Youth Development. Individual differences in timing and tempo were extracted with models of logistic growth. Differential relations emerged for how boys' and girls' timing and tempo of development were related to physical characteristics (body mass index, height, and weight) and psychological outcomes (internalizing problems, externalizing problems, and risky sexual behavior). Timing and tempo are associated in boys but not girls. Pubertal timing and tempo are particularly important for predicting psychological outcomes in girls but only sparsely related to boys' psychological outcomes. Results highlight the importance of considering the nonlinear nature of puberty and expand the repertoire of possibilities for examining important aspects of how and when pubertal processes contribute to development.

  5. Individual differences in change blindness

    OpenAIRE

    Bergmann, Katharina Verena

    2016-01-01

    The present work shows the existence of systematic individual differences in change blindness. It can be concluded that the sensitivity for changes is a trait. That is, persons differ in their ability to detect changes, independent from the situation or the measurement method. Moreover, there are two explanations for individual differences in change blindness: a) capacity differences in visual selective attention that may be influenced by top-down activated attention helping to focus attentio...

  6. A reciprocal model of face recognition and autistic traits: evidence from an individual differences perspective.

    Science.gov (United States)

    Halliday, Drew W R; MacDonald, Stuart W S; Scherf, K Suzanne; Sherf, Suzanne K; Tanaka, James W

    2014-01-01

    Although not a core symptom of the disorder, individuals with autism often exhibit selective impairments in their face processing abilities. Importantly, the reciprocal connection between autistic traits and face perception has rarely been examined within the typically developing population. In this study, university participants from the social sciences, physical sciences, and humanities completed a battery of measures that assessed face, object and emotion recognition abilities, general perceptual-cognitive style, and sub-clinical autistic traits (the Autism Quotient (AQ)). We employed separate hierarchical multiple regression analyses to evaluate which factors could predict face recognition scores and AQ scores. Gender, object recognition performance, and AQ scores predicted face recognition behaviour. Specifically, males, individuals with more autistic traits, and those with lower object recognition scores performed more poorly on the face recognition test. Conversely, university major, gender and face recognition performance reliably predicted AQ scores. Science majors, males, and individuals with poor face recognition skills showed more autistic-like traits. These results suggest that the broader autism phenotype is associated with lower face recognition abilities, even among typically developing individuals.

  7. Individual differences in anxiety responses to stressful situations : A three-mode component analysis model

    NARCIS (Netherlands)

    Van Mechelen, Iven; Kiers, Henk A.L.

    1999-01-01

    The three-mode component analysis model is discussed as a tool for a contextualized study of personality. When applied to person x situation x response data, the model includes sets of latent dimensions for persons, situations, and responses as well as a so-called core array, which may be considered

  8. Brain Mechanisms Underlying Individual Differences in Reaction to Stress: An Animal Model

    National Research Council Canada - National Science Library

    Siegel, Jerome

    1997-01-01

    .... We developed an animal model of this important dimension of behavior in which we reported that cats and rats who display high levels of exploration, activity, aggression, and risk taking show VEP...

  9. Modeling the Direct and Indirect Determinants of Different Types of Individual Job Performance

    Science.gov (United States)

    2008-06-01

    dimension is an element of task performance (Johnson, 2003), the middle three dimensions all tap different aspects of citizenship performance (Borman...Record your effectiveness rating for each response (from 1 to 7) on the line to the eft of the response. In addition, select which ONE response out of

  10. Cognitive Psychology Meets Psychometric Theory: On the Relation between Process Models for Decision Making and Latent Variable Models for Individual Differences

    Science.gov (United States)

    van der Maas, Han L. J.; Molenaar, Dylan; Maris, Gunter; Kievit, Rogier A.; Borsboom, Denny

    2011-01-01

    This article analyzes latent variable models from a cognitive psychology perspective. We start by discussing work by Tuerlinckx and De Boeck (2005), who proved that a diffusion model for 2-choice response processes entails a 2-parameter logistic item response theory (IRT) model for individual differences in the response data. Following this line…

  11. Modeling Individual Differences in Within-Person Variation of Negative and Positive Affect in a Mixed Effects Location Scale Model Using BUGS/JAGS

    Science.gov (United States)

    Rast, Philippe; Hofer, Scott M.; Sparks, Catharine

    2012-01-01

    A mixed effects location scale model was used to model and explain individual differences in within-person variability of negative and positive affect across 7 days (N=178) within a measurement burst design. The data come from undergraduate university students and are pooled from a study that was repeated at two consecutive years. Individual…

  12. The Impact of Individual Differences, Types of Model and Social Settings on Block Building Performance among Chinese Preschoolers

    Directory of Open Access Journals (Sweden)

    Mi Tian

    2018-01-01

    Full Text Available Children’s block building performances are used as indicators of other abilities in multiple domains. In the current study, we examined individual differences, types of model and social settings as influences on children’s block building performance. Chinese preschoolers (N = 180 participated in a block building activity in a natural setting, and performance was assessed with multiple measures in order to identify a range of specific skills. Using scores generated across these measures, three dependent variables were analyzed: block building skills, structural balance and structural features. An overall MANOVA showed that there were significant main effects of gender and grade level across most measures. Types of model showed no significant effect in children’s block building. There was a significant main effect of social settings on structural features, with the best performance in the 5-member group, followed by individual and then the 10-member block building. These findings suggest that boys performed better than girls in block building activity. Block building performance increased significantly from 1st to 2nd year of preschool, but not from second to third. The preschoolers created more representational constructions when presented with a model made of wooden rather than with a picture. There was partial evidence that children performed better when working with peers in a small group than when working alone or working in a large group. It is suggested that future study should examine other modalities rather than the visual one, diversify the samples and adopt a longitudinal investigation.

  13. The Impact of Individual Differences, Types of Model and Social Settings on Block Building Performance among Chinese Preschoolers.

    Science.gov (United States)

    Tian, Mi; Deng, Zhu; Meng, Zhaokun; Li, Rui; Zhang, Zhiyi; Qi, Wenhui; Wang, Rui; Yin, Tingting; Ji, Menghui

    2018-01-01

    Children's block building performances are used as indicators of other abilities in multiple domains. In the current study, we examined individual differences, types of model and social settings as influences on children's block building performance. Chinese preschoolers ( N = 180) participated in a block building activity in a natural setting, and performance was assessed with multiple measures in order to identify a range of specific skills. Using scores generated across these measures, three dependent variables were analyzed: block building skills, structural balance and structural features. An overall MANOVA showed that there were significant main effects of gender and grade level across most measures. Types of model showed no significant effect in children's block building. There was a significant main effect of social settings on structural features, with the best performance in the 5-member group, followed by individual and then the 10-member block building. These findings suggest that boys performed better than girls in block building activity. Block building performance increased significantly from 1st to 2nd year of preschool, but not from second to third. The preschoolers created more representational constructions when presented with a model made of wooden rather than with a picture. There was partial evidence that children performed better when working with peers in a small group than when working alone or working in a large group. It is suggested that future study should examine other modalities rather than the visual one, diversify the samples and adopt a longitudinal investigation.

  14. Acculturation of Iranians in the United States, the United Kingdom, and the Netherlands A Test of the Multidimensional Individual Difference Acculturation (MIDA) Model

    NARCIS (Netherlands)

    Safdar, S.; Struthers, W.; Van Oudenhoven, J.P.

    The present study tested the generalizability of a multidimensional individual difference acculturation (MIDA) model in three cultural contexts. The model includes three predictor variables (Psychosocial Resources, Connectedness, and Hassles), predicting three outcome adaptation variables (In-Group

  15. Individual differences and the characterization of animal models of psychopathology: a strong challenge and a good opportunity.

    Science.gov (United States)

    Armario, Antonio; Nadal, Roser

    2013-01-01

    Despite the development of valuable new techniques (i.e., genetics, neuroimage) for the study of the neurobiological substrate of psychiatric diseases, there are strong limitations in the information that can be gathered from human studies. It is thus critical to develop appropriate animal models of psychiatric diseases to characterize their putative biological bases and the development of new therapeutic strategies. The present review tries to offer a general perspective and several examples of how individual differences in animals can contribute to explain differential susceptibility to develop behavioral alterations, but also emphasizes methodological problems that can lead to inappropriate or over-simplistic interpretations. A critical analysis of the approaches currently used could contribute to obtain more reliable data and allow taking full advantage of new and sophisticated technologies. The discussion is mainly focused on anxiety-like and to a lower extent on depression-like behavior in rodents.

  16. Incorporating Learning Characteristics into Automatic Essay Scoring Models: What Individual Differences and Linguistic Features Tell Us about Writing Quality

    Science.gov (United States)

    Crossley, Scott A.; Allen, Laura K.; Snow, Erica L.; McNamara, Danielle S.

    2016-01-01

    This study investigates a novel approach to automatically assessing essay quality that combines natural language processing approaches that assess text features with approaches that assess individual differences in writers such as demographic information, standardized test scores, and survey results. The results demonstrate that combining text…

  17. Modelling individual differences in the form of Pavlovian conditioned approach responses: a dual learning systems approach with factored representations.

    Directory of Open Access Journals (Sweden)

    Florian Lesaint

    2014-02-01

    Full Text Available Reinforcement Learning has greatly influenced models of conditioning, providing powerful explanations of acquired behaviour and underlying physiological observations. However, in recent autoshaping experiments in rats, variation in the form of Pavlovian conditioned responses (CRs and associated dopamine activity, have questioned the classical hypothesis that phasic dopamine activity corresponds to a reward prediction error-like signal arising from a classical Model-Free system, necessary for Pavlovian conditioning. Over the course of Pavlovian conditioning using food as the unconditioned stimulus (US, some rats (sign-trackers come to approach and engage the conditioned stimulus (CS itself - a lever - more and more avidly, whereas other rats (goal-trackers learn to approach the location of food delivery upon CS presentation. Importantly, although both sign-trackers and goal-trackers learn the CS-US association equally well, only in sign-trackers does phasic dopamine activity show classical reward prediction error-like bursts. Furthermore, neither the acquisition nor the expression of a goal-tracking CR is dopamine-dependent. Here we present a computational model that can account for such individual variations. We show that a combination of a Model-Based system and a revised Model-Free system can account for the development of distinct CRs in rats. Moreover, we show that revising a classical Model-Free system to individually process stimuli by using factored representations can explain why classical dopaminergic patterns may be observed for some rats and not for others depending on the CR they develop. In addition, the model can account for other behavioural and pharmacological results obtained using the same, or similar, autoshaping procedures. Finally, the model makes it possible to draw a set of experimental predictions that may be verified in a modified experimental protocol. We suggest that further investigation of factored representations in

  18. Modelling Individual Differences in the Form of Pavlovian Conditioned Approach Responses: A Dual Learning Systems Approach with Factored Representations

    Science.gov (United States)

    Lesaint, Florian; Sigaud, Olivier; Flagel, Shelly B.; Robinson, Terry E.; Khamassi, Mehdi

    2014-01-01

    Reinforcement Learning has greatly influenced models of conditioning, providing powerful explanations of acquired behaviour and underlying physiological observations. However, in recent autoshaping experiments in rats, variation in the form of Pavlovian conditioned responses (CRs) and associated dopamine activity, have questioned the classical hypothesis that phasic dopamine activity corresponds to a reward prediction error-like signal arising from a classical Model-Free system, necessary for Pavlovian conditioning. Over the course of Pavlovian conditioning using food as the unconditioned stimulus (US), some rats (sign-trackers) come to approach and engage the conditioned stimulus (CS) itself – a lever – more and more avidly, whereas other rats (goal-trackers) learn to approach the location of food delivery upon CS presentation. Importantly, although both sign-trackers and goal-trackers learn the CS-US association equally well, only in sign-trackers does phasic dopamine activity show classical reward prediction error-like bursts. Furthermore, neither the acquisition nor the expression of a goal-tracking CR is dopamine-dependent. Here we present a computational model that can account for such individual variations. We show that a combination of a Model-Based system and a revised Model-Free system can account for the development of distinct CRs in rats. Moreover, we show that revising a classical Model-Free system to individually process stimuli by using factored representations can explain why classical dopaminergic patterns may be observed for some rats and not for others depending on the CR they develop. In addition, the model can account for other behavioural and pharmacological results obtained using the same, or similar, autoshaping procedures. Finally, the model makes it possible to draw a set of experimental predictions that may be verified in a modified experimental protocol. We suggest that further investigation of factored representations in

  19. Modelling individual differences in the form of Pavlovian conditioned approach responses: a dual learning systems approach with factored representations.

    Science.gov (United States)

    Lesaint, Florian; Sigaud, Olivier; Flagel, Shelly B; Robinson, Terry E; Khamassi, Mehdi

    2014-02-01

    Reinforcement Learning has greatly influenced models of conditioning, providing powerful explanations of acquired behaviour and underlying physiological observations. However, in recent autoshaping experiments in rats, variation in the form of Pavlovian conditioned responses (CRs) and associated dopamine activity, have questioned the classical hypothesis that phasic dopamine activity corresponds to a reward prediction error-like signal arising from a classical Model-Free system, necessary for Pavlovian conditioning. Over the course of Pavlovian conditioning using food as the unconditioned stimulus (US), some rats (sign-trackers) come to approach and engage the conditioned stimulus (CS) itself - a lever - more and more avidly, whereas other rats (goal-trackers) learn to approach the location of food delivery upon CS presentation. Importantly, although both sign-trackers and goal-trackers learn the CS-US association equally well, only in sign-trackers does phasic dopamine activity show classical reward prediction error-like bursts. Furthermore, neither the acquisition nor the expression of a goal-tracking CR is dopamine-dependent. Here we present a computational model that can account for such individual variations. We show that a combination of a Model-Based system and a revised Model-Free system can account for the development of distinct CRs in rats. Moreover, we show that revising a classical Model-Free system to individually process stimuli by using factored representations can explain why classical dopaminergic patterns may be observed for some rats and not for others depending on the CR they develop. In addition, the model can account for other behavioural and pharmacological results obtained using the same, or similar, autoshaping procedures. Finally, the model makes it possible to draw a set of experimental predictions that may be verified in a modified experimental protocol. We suggest that further investigation of factored representations in computational

  20. Individual differences in imagination inflation.

    Science.gov (United States)

    Heaps, C; Nash, M

    1999-06-01

    Garry, Manning, Loftus, and Sherman (1996) found that when adult subjects imagined childhood events, these events were subsequentlyjudged as more likely to have occurred than were not-imagined events. The authors termed this effect imagination inflation. We replicated the effect, using a novel set of Life Events Inventory events. Further, we tested whether the effect is related to four subject characteristics possibly associated with false memory creation. The extent to which subjects inflated judged likelihood following imagined events was associated with indices of hypnotic suggestibility and dissociativity, but not with vividness of imagery or interrogative suggestibility. Results suggest that imagination plays a role in subsequent likelihood judgments regarding childhood events, and that some individuals are more likely than others to experience imagination inflation.

  1. Cognitive psychology meets psychometric theory: on the relation between process models for decision making and latent variable models for individual differences.

    Science.gov (United States)

    van der Maas, Han L J; Molenaar, Dylan; Maris, Gunter; Kievit, Rogier A; Borsboom, Denny

    2011-04-01

    This article analyzes latent variable models from a cognitive psychology perspective. We start by discussing work by Tuerlinckx and De Boeck (2005), who proved that a diffusion model for 2-choice response processes entails a 2-parameter logistic item response theory (IRT) model for individual differences in the response data. Following this line of reasoning, we discuss the appropriateness of IRT for measuring abilities and bipolar traits, such as pro versus contra attitudes. Surprisingly, if a diffusion model underlies the response processes, IRT models are appropriate for bipolar traits but not for ability tests. A reconsideration of the concept of ability that is appropriate for such situations leads to a new item response model for accuracy and speed based on the idea that ability has a natural zero point. The model implies fundamentally new ways to think about guessing, response speed, and person fit in IRT. We discuss the relation between this model and existing models as well as implications for psychology and psychometrics. 2011 APA, all rights reserved

  2. Individual Differences in Human Reliability Analysis

    Energy Technology Data Exchange (ETDEWEB)

    Jeffrey C. Joe; Ronald L. Boring

    2014-06-01

    While human reliability analysis (HRA) methods include uncertainty in quantification, the nominal model of human error in HRA typically assumes that operator performance does not vary significantly when they are given the same initiating event, indicators, procedures, and training, and that any differences in operator performance are simply aleatory (i.e., random). While this assumption generally holds true when performing routine actions, variability in operator response has been observed in multiple studies, especially in complex situations that go beyond training and procedures. As such, complexity can lead to differences in operator performance (e.g., operator understanding and decision-making). Furthermore, psychological research has shown that there are a number of known antecedents (i.e., attributable causes) that consistently contribute to observable and systematically measurable (i.e., not random) differences in behavior. This paper reviews examples of individual differences taken from operational experience and the psychological literature. The impact of these differences in human behavior and their implications for HRA are then discussed. We propose that individual differences should not be treated as aleatory, but rather as epistemic. Ultimately, by understanding the sources of individual differences, it is possible to remove some epistemic uncertainty from analyses.

  3. An ontogenetic perspective on individual differences

    NARCIS (Netherlands)

    Senner, N.R.; Conklin, J.R.; Piersma, T.

    2015-01-01

    Phenotypic differences among individuals can arise during any stage of life. Although several distinct processes underlying individual differences have been defined and studied (e.g. parental effects, senescence), we lack an explicit, unified perspective for understanding how these processes

  4. Modeling the Covariance Structure of Complex Datasets Using Cognitive Models: An Application to Individual Differences and the Heritability of Cognitive Ability.

    Science.gov (United States)

    Evans, Nathan J; Steyvers, Mark; Brown, Scott D

    2018-06-05

    Understanding individual differences in cognitive performance is an important part of understanding how variations in underlying cognitive processes can result in variations in task performance. However, the exploration of individual differences in the components of the decision process-such as cognitive processing speed, response caution, and motor execution speed-in previous research has been limited. Here, we assess the heritability of the components of the decision process, with heritability having been a common aspect of individual differences research within other areas of cognition. Importantly, a limitation of previous work on cognitive heritability is the underlying assumption that variability in response times solely reflects variability in the speed of cognitive processing. This assumption has been problematic in other domains, due to the confounding effects of caution and motor execution speed on observed response times. We extend a cognitive model of decision-making to account for relatedness structure in a twin study paradigm. This approach can separately quantify different contributions to the heritability of response time. Using data from the Human Connectome Project, we find strong evidence for the heritability of response caution, and more ambiguous evidence for the heritability of cognitive processing speed and motor execution speed. Our study suggests that the assumption made in previous studies-that the heritability of cognitive ability is based on cognitive processing speed-may be incorrect. More generally, our methodology provides a useful avenue for future research in complex data that aims to analyze cognitive traits across different sources of related data, whether the relation is between people, tasks, experimental phases, or methods of measurement. © 2018 Cognitive Science Society, Inc.

  5. Environmental assessment of different management options for individual waste fractions by means of life-cycle assessment modelling

    DEFF Research Database (Denmark)

    Manfredi, Simone; Tonini, Davide; Christensen, Thomas Højlund

    2011-01-01

    and environmental factors involved, including energy generation from landfill gas and storage of biogenic carbon. Leachate and gas emissions associated to each individual waste fraction have been estimated by means of a mathematical modelling. This approach towards landfilling emissions allows for a more precise...... quantification of the landfill impacts when comparing management options for selected waste fractions.Results from the life-cycle impact assessment (LCIA) show that the environmental performance estimated for landfilling with energy recovery of the fractions “organics” and “recyclable paper” is comparable...... with composting (for “organics”) and incineration (for “recyclable paper”). This however requires high degree of control over gas and leachate emissions, high gas collection efficiency and extensive gas utilization at the landfill. For the other waste fractions, recycling and incineration are favourable, although...

  6. Neural responses to nostalgia-evoking music modeled by elements of dynamic musical structure and individual differences in affective traits.

    Science.gov (United States)

    Barrett, Frederick S; Janata, Petr

    2016-10-01

    Nostalgia is an emotion that is most commonly associated with personally and socially relevant memories. It is primarily positive in valence and is readily evoked by music. It is also an idiosyncratic experience that varies between individuals based on affective traits. We identified frontal, limbic, paralimbic, and midbrain brain regions in which the strength of the relationship between ratings of nostalgia evoked by music and blood-oxygen-level-dependent (BOLD) signal was predicted by affective personality measures (nostalgia proneness and the sadness scale of the Affective Neuroscience Personality Scales) that are known to modulate the strength of nostalgic experiences. We also identified brain areas including the inferior frontal gyrus, substantia nigra, cerebellum, and insula in which time-varying BOLD activity correlated more strongly with the time-varying tonal structure of nostalgia-evoking music than with music that evoked no or little nostalgia. These findings illustrate one way in which the reward and emotion regulation networks of the brain are recruited during the experiencing of complex emotional experiences triggered by music. These findings also highlight the importance of considering individual differences when examining the neural responses to strong and idiosyncratic emotional experiences. Finally, these findings provide a further demonstration of the use of time-varying stimulus-specific information in the investigation of music-evoked experiences. Copyright © 2016 Elsevier Ltd. All rights reserved.

  7. Cognitive psychology meets psychometric theory: on the relation between process models for decision making and latent variable models for individual differences

    NARCIS (Netherlands)

    van der Maas, H.L.J.; Molenaar, D.; Maris, G.; Kievit, R.A.; Borsboom, D.

    2011-01-01

    This article analyzes latent variable models from a cognitive psychology perspective. We start by discussing work by Tuerlinckx and De Boeck (2005), who proved that a diffusion model for 2-choice response processes entails a 2-parameter logistic item response theory (IRT) model for individual

  8. Individual differences in cognition among teleost fishes.

    Science.gov (United States)

    Lucon-Xiccato, Tyrone; Bisazza, Angelo

    2017-08-01

    Individual differences in cognitive abilities have been thoroughly investigated in humans and to a lesser extent in other mammals. Despite the growing interest in studying cognition in other taxonomic groups, data on individual differences are scarce for non-mammalian species. Here, we review the literature on individual differences in cognitive abilities in teleost fishes. Relatively few studies have directly addressed this topic and have provided evidence of consistent and heritable individual variation in cognitive abilities in fish. We found much more evidence of individual cognitive differences in other research areas, namely sex differences, personality differences, cerebral lateralisation and comparison between populations. Altogether, these studies suggest that individual differences in cognition are as common in fish as in warm-blooded vertebrates. Based on the example of research on mammals, we suggest directions for future investigation in fish. Copyright © 2017 Elsevier B.V. All rights reserved.

  9. Anatomy of Student Models in Adaptive Learning Systems: A Systematic Literature Review of Individual Differences from 2001 to 2013

    Science.gov (United States)

    Nakic, Jelena; Granic, Andrina; Glavinic, Vlado

    2015-01-01

    This study brings an evidence-based review of user individual characteristics employed as sources of adaptation in recent adaptive learning systems. Twenty-two user individual characteristics were explored in a systematically designed search procedure, while 17 of them were identified as sources of adaptation in final selection. The content…

  10. Individual differences in visual perception and memory

    NARCIS (Netherlands)

    Colizoli, O.

    2014-01-01

    There is substantial variation in perception and memory in humans. There are individuals who cannot see red at all, and there are individuals who hear colors and taste words. What determines the differences and similarities between individuals' perception and memory? Can we characterize the neural

  11. Age-related changes in predictive capacity versus internal model adaptability: electrophysiological evidence that individual differences outweigh effects of age

    Directory of Open Access Journals (Sweden)

    Ina eBornkessel-Schlesewsky

    2015-11-01

    Full Text Available Hierarchical predictive coding has been identified as a possible unifying principle of brain function, and recent work in cognitive neuroscience has examined how it may be affected by age–related changes. Using language comprehension as a test case, the present study aimed to dissociate age-related changes in prediction generation versus internal model adaptation following a prediction error. Event-related brain potentials (ERPs were measured in a group of older adults (60–81 years; n=40 as they read sentences of the form The opposite of black is white/yellow/nice. Replicating previous work in young adults, results showed a target-related P300 for the expected antonym (white; an effect assumed to reflect a prediction match, and a graded N400 effect for the two incongruous conditions (i.e. a larger N400 amplitude for the incongruous continuation not related to the expected antonym, nice, versus the incongruous associated condition, yellow. These effects were followed by a late positivity, again with a larger amplitude in the incongruous non-associated versus incongruous associated condition. Analyses using linear mixed-effects models showed that the target-related P300 effect and the N400 effect for the incongruous non-associated condition were both modulated by age, thus suggesting that age-related changes affect both prediction generation and model adaptation. However, effects of age were outweighed by the interindividual variability of ERP responses, as reflected in the high proportion of variance captured by the inclusion of by-condition random slopes for participants and items. We thus argue that – at both a neurophysiological and a functional level – the notion of general differences between language processing in young and older adults may only be of limited use, and that future research should seek to better understand the causes of interindividual variability in the ERP responses of older adults and its relation to cognitive

  12. Disturbance of sleep by noise: Individual differences

    Science.gov (United States)

    Wilkinson, R. T.

    1984-07-01

    The literature on the effects of noise on sleep is searched for evidence on individual differences along the dimensions of age, sex, occupation, personality, neuroticism, and mental health. With the exception of age, little firm evidence is found. Thus there remains a need to establish at better than the anecdotal level whether or not real individual differences exist.

  13. Individual Differences in Susceptibility to Inattentional Blindness

    Science.gov (United States)

    Seegmiller, Janelle K.; Watson, Jason M.; Strayer, David L.

    2011-01-01

    Inattentional blindness refers to the finding that people do not always see what appears in their gaze. Though inattentional blindness affects large percentages of people, it is unclear if there are individual differences in susceptibility. The present study addressed whether individual differences in attentional control, as reflected by…

  14. An evolutionary ecology of individual differences

    Science.gov (United States)

    Dall, Sasha R. X.; Bell, Alison M.; Bolnick, Daniel I.; Ratnieks, Francis L. W.

    2014-01-01

    Individuals often differ in what they do. This has been recognised since antiquity. Nevertheless, the ecological and evolutionary significance of such variation is attracting widespread interest, which is burgeoning to an extent that is fragmenting the literature. As a first attempt at synthesis, we focus on individual differences in behaviour within populations that exceed the day-to-day variation in individual behaviour (i.e. behavioural specialisation). Indeed, the factors promoting ecologically relevant behavioural specialisation within natural populations are likely to have far-reaching ecological and evolutionary consequences. We discuss such individual differences from three distinct perspectives: individual niche specialisations, the division of labour within insect societies and animal personality variation. In the process, while recognising that each area has its own unique motivations, we identify a number of opportunities for productive ‘crossfertilisation’ among the (largely independent) bodies of work. We conclude that a complete understanding of evolutionarily and ecologically relevant individual differences must specify how ecological interactions impact the basic biological process (e.g. Darwinian selection, development and information processing) that underpin the organismal features determining behavioural specialisations. Moreover, there is likely to be covariation amongst behavioural specialisations. Thus, we sketch the key elements of a general framework for studying the evolutionary ecology of individual differences. PMID:22897772

  15. Large individual differences in free recall

    OpenAIRE

    Tarnow, Eugen

    2016-01-01

    Using single factor ANOVA I show that there are large individual differences in free recall ({\\eta} ranges from 0.09-0.26) including the total recall, the balance between recency and primacy, and the initial recall (subsequent recalls show smaller individual differences). All three memory properties are relatively uncorrelated. The variance in the initial position may be a measure of executive control and is correlated with total recall (the smaller the variation, the larger the recall).

  16. A Process Model of L2 Learners' Motivation: From the Perspectives of General Tendency and Individual Differences

    Science.gov (United States)

    Hiromori, Tomohito

    2009-01-01

    The purpose of this study is to examine a process model of L2 learners' motivation. To investigate the overall process of motivation, the motivation of 148 university students was analyzed. Data were collected on three variables from the pre-decisional phase of motivation (i.e., value, expectancy, and intention) and four variables from the…

  17. Individual Differences in Men’s Misperception of Women’s Sexual Intent: Application and Extension of the Confluence Model

    OpenAIRE

    Wegner, Rhiana; Abbey, Antonia

    2016-01-01

    Men are more likely than women to misperceive a cross-sex companion’s degree of sexual interest. The current study extends previous research by using the confluence model (Malamuth et al., 1991) to examine how narcissism and impulsive sensation-seeking are directly and indirectly associated with men’s misperception of women’s sexual interest. A community sample of young, single men (N = 470) completed audio computer-assisted self-interviews. Using path analyses, hostile masculinity and impers...

  18. IASM: Individualized activity space modeler

    Science.gov (United States)

    Hasanzadeh, Kamyar

    2018-01-01

    Researchers from various disciplines have long been interested in analyzing and describing human mobility patterns. Activity space (AS), defined as an area encapsulating daily human mobility and activities, has been at the center of this interest. However, given the applied nature of research in this field and the complexity that advanced geographical modeling can pose to its users, the proposed models remain simplistic and inaccurate in many cases. Individualized Activity Space Modeler (IASM) is a geographic information system (GIS) toolbox, written in Python programming language using ESRI's Arcpy module, comprising four tools aiming to facilitate the use of advanced activity space models in empirical research. IASM provides individual-based and context-sensitive tools to estimate home range distances, delineate activity spaces, and model place exposures using individualized geographical data. In this paper, we describe the design and functionality of IASM, and provide an example of how it performs on a spatial dataset collected through an online map-based survey.

  19. Individual differences in fundamental social motives.

    Science.gov (United States)

    Neel, Rebecca; Kenrick, Douglas T; White, Andrew Edward; Neuberg, Steven L

    2016-06-01

    Motivation has long been recognized as an important component of how people both differ from, and are similar to, each other. The current research applies the biologically grounded fundamental social motives framework, which assumes that human motivational systems are functionally shaped to manage the major costs and benefits of social life, to understand individual differences in social motives. Using the Fundamental Social Motives Inventory, we explore the relations among the different fundamental social motives of Self-Protection, Disease Avoidance, Affiliation, Status, Mate Seeking, Mate Retention, and Kin Care; the relationships of the fundamental social motives to other individual difference and personality measures including the Big Five personality traits; the extent to which fundamental social motives are linked to recent life experiences; and the extent to which life history variables (e.g., age, sex, childhood environment) predict individual differences in the fundamental social motives. Results suggest that the fundamental social motives are a powerful lens through which to examine individual differences: They are grounded in theory, have explanatory value beyond that of the Big Five personality traits, and vary meaningfully with a number of life history variables. A fundamental social motives approach provides a generative framework for considering the meaning and implications of individual differences in social motivation. (PsycINFO Database Record (c) 2016 APA, all rights reserved).

  20. Modeling individual differences in randomized experiments using growth models: Recommendations for design, statistical analysis and reporting of results of internet interventions

    Directory of Open Access Journals (Sweden)

    Hugo Hesser

    2015-05-01

    Full Text Available Growth models (also known as linear mixed effects models, multilevel models, and random coefficients models have the capability of studying change at the group as well as the individual level. In addition, these methods have documented advantages over traditional data analytic approaches in the analysis of repeated-measures data. These advantages include, but are not limited to, the ability to incorporate time-varying predictors, handle dependence among repeated observations in a very flexible manner, and to provide accurate estimates with missing data under fairly unrestrictive missing data assumptions. The flexibility of the growth curve modeling approach to the analysis of change makes it the preferred choice in the evaluation of direct, indirect and moderated intervention effects. Although offering many benefits, growth models present challenges in terms of design, analysis and reporting of results. This paper provides a nontechnical overview of growth models in the analysis of change in randomized experiments and advocates for their use in the field of internet interventions. Practical recommendations for design, analysis and reporting of results from growth models are provided.

  1. Individual differences in conflict detection during reasoning.

    Science.gov (United States)

    Frey, Darren; Johnson, Eric D; De Neys, Wim

    2018-05-01

    Decades of reasoning and decision-making research have established that human judgment is often biased by intuitive heuristics. Recent "error" or bias detection studies have focused on reasoners' abilities to detect whether their heuristic answer conflicts with logical or probabilistic principles. A key open question is whether there are individual differences in this bias detection efficiency. Here we present three studies in which co-registration of different error detection measures (confidence, response time and confidence response time) allowed us to assess bias detection sensitivity at the individual participant level in a range of reasoning tasks. The results indicate that although most individuals show robust bias detection, as indexed by increased latencies and decreased confidence, there is a subgroup of reasoners who consistently fail to do so. We discuss theoretical and practical implications for the field.

  2. Everyday Attention Failures: An Individual Differences Investigation

    Science.gov (United States)

    Unsworth, Nash; McMillan, Brittany D.; Brewer, Gene A.; Spillers, Gregory J.

    2012-01-01

    The present study examined individual differences in everyday attention failures. Undergraduate students completed various cognitive ability measures in the laboratory and recorded everyday attention failures in a diary over the course of a week. The majority of attention failures were failures of distraction or mind wandering in educational…

  3. Individual Hearing Loss: Characterization, Modelling, Compensation Strategies

    DEFF Research Database (Denmark)

    Santurette, Sébastien; Dau, Torsten; Christensen-Dalsgaard, Jakob

    2016-01-01

    account for such individual differences, which make it challenging to find adequate compensation strategies in hearing devices. How to characterize, model, and compensate for individual hearing loss were the main topics of the fifth International Symposium on Auditory and Audiological Research (ISAAR...

  4. Modelling the Immune Response to Cancer: An Individual-Based Approach Accounting for the Difference in Movement Between Inactive and Activated T Cells.

    Science.gov (United States)

    Macfarlane, Fiona R; Lorenzi, Tommaso; Chaplain, Mark A J

    2018-06-01

    A growing body of experimental evidence indicates that immune cells move in an unrestricted search pattern if they are in the pre-activated state, whilst they tend to stay within a more restricted area upon activation induced by the presence of tumour antigens. This change in movement is not often considered in the existing mathematical models of the interactions between immune cells and cancer cells. With the aim to fill such a gap in the existing literature, in this work we present a spatially structured individual-based model of tumour-immune competition that takes explicitly into account the difference in movement between inactive and activated immune cells. In our model, a Lévy walk is used to capture the movement of inactive immune cells, whereas Brownian motion is used to describe the movement of antigen-activated immune cells. The effects of activation of immune cells, the proliferation of cancer cells and the immune destruction of cancer cells are also modelled. We illustrate the ability of our model to reproduce qualitatively the spatial trajectories of immune cells observed in experimental data of single-cell tracking. Computational simulations of our model further clarify the conditions for the onset of a successful immune action against cancer cells and may suggest possible targets to improve the efficacy of cancer immunotherapy. Overall, our theoretical work highlights the importance of taking into account spatial interactions when modelling the immune response to cancer cells.

  5. Similarities and Differences between Individuals Seeking Treatment for Gambling Problems vs. Alcohol and Substance Use Problems in Relation to the Progressive Model of Self-stigma

    Directory of Open Access Journals (Sweden)

    Belle Gavriel-Fried

    2017-06-01

    Full Text Available Aims: People with gambling as well as substance use problems who are exposed to public stigmatization may internalize and apply it to themselves through a mechanism known as self-stigma. This study implemented the Progressive Model for Self-Stigma which consists four sequential interrelated stages: awareness, agreement, application and harm on three groups of individuals with gambling, alcohol and other substance use problems. It explored whether the two guiding assumptions of this model (each stage is precondition for the following stage which are trickle-down in nature, and correlations between proximal stages should be larger than correlations between more distant stages would differentiate people with gambling problems from those with alcohol and other substance use problems in terms of their patterns of self-stigma and in terms of the stages in the model.Method: 37 individuals with gambling problems, 60 with alcohol problems and 51 with drug problems who applied for treatment in rehabilitation centers in Israel in 2015–2016 were recruited. They completed the Self-stigma of Mental Illness Scale-Short Form which was adapted by changing the term “mental health” to gambling, alcohol or drugs, and the DSM-5-diagnostic criteria for gambling, alcohol or drug disorder.Results: The assumptions of the model were broadly confirmed: a repeated measures ANCOVA revealed that in all three groups there was a difference between first two stages (aware and agree and the latter stages (apply and harm. In addition, the gambling group differed from the drug use and alcohol groups on the awareness stage: individuals with gambling problems were less likely to be aware of stigma than people with substance use or alcohol problems.Conclusion: The internalization of stigma among individuals with gambling problems tends to work in a similar way as for those with alcohol or drug problems. The differences between the gambling group and the alcohol and other

  6. Individual Differences in Language Acquisition and Processing.

    Science.gov (United States)

    Kidd, Evan; Donnelly, Seamus; Christiansen, Morten H

    2018-02-01

    Humans differ in innumerable ways, with considerable variation observable at every level of description, from the molecular to the social. Traditionally, linguistic and psycholinguistic theory has downplayed the possibility of meaningful differences in language across individuals. However, it is becoming increasingly evident that there is significant variation among speakers at any age as well as across the lifespan. Here, we review recent research in psycholinguistics, and argue that a focus on individual differences (IDs) provides a crucial source of evidence that bears strongly upon core issues in theories of the acquisition and processing of language; specifically, the role of experience in language acquisition, processing, and attainment, and the architecture of the language system. Copyright © 2017 Elsevier Ltd. All rights reserved.

  7. Workaholism in Brazil: measurement and individual differences.

    Science.gov (United States)

    Romeo, Marina; Yepes-Baldó, Montserrat; Berger, Rita; Netto Da Costa, Francisco Franco

    2014-01-01

    The aim of this research is the measurement and assessment of individual differences of workaholism in Brazil, an important issue which affects the competitiveness of companies. The WART 15-PBV was applied to a sample of 153 managers from companies located in Brazil, 82 (53.6%) women and 71 (46.4%) men. Ages ranged from 20 to 69 years with an average value of 41 (SD=9.06). We analyzed, on one hand, the factor structure of the questionnaire, its internal consistency and convergent (with the Dutch Work Addiction Scale - DUWAS) and criterion validity (with General Health Questionnaire – GHQ). On the other hand, we analyzed individual gender differences on workaholism. WART15-PBV has good psychometric properties, and evidence for convergent and criterion validity. Females and males differed on Impaired Communication / Self-Absorption dimension. This dimension has a direct effect only on men’s health perception, while Compulsive tendencies dimension has a direct effect for both genders. The findings suggest the WART15-PBV is a valid measure of workaholism that would contribute to the workers’ health and their professional and personal life, in order to encourage adequate conditions in the workplace taking into account workers’ individual differences.

  8. Cultural differences are not always reducible to individual differences.

    Science.gov (United States)

    Na, Jinkyung; Grossmann, Igor; Varnum, Michael E W; Kitayama, Shinobu; Gonzalez, Richard; Nisbett, Richard E

    2010-04-06

    We show that differences in social orientation and in cognition that exist between cultures and social classes do not necessarily have counterparts in individual differences within those groups. Evidence comes from a large-scale study conducted with 10 measures of independent vs. interdependent social orientation and 10 measures of analytic vs. holistic cognitive style. The social measures successfully distinguish between interdependence (viewing oneself as embedded in relations with others) and independence (viewing oneself as disconnected from others) at the group level. However, the correlations among the measures were negligible. Similar results were obtained for the cognitive measures, for which there are no coherent individual differences despite the validity of the construct at the group level. We conclude that behavioral constructs that distinguish among groups need not be valid as measures of individual differences.

  9. Individual differences in attention influence perceptual decision making

    OpenAIRE

    Nunez, Michael D.; Srinivasan, Ramesh; Vandekerckhove, Joachim

    2015-01-01

    © 2015 Nunez, Srinivasan and Vandekerckhove. Sequential sampling decision-making models have been successful in accounting for reaction time (RT) and accuracy data in two-alternative forced choice tasks. These models have been used to describe the behavior of populations of participants, and explanatory structures have been proposed to account for between individual variability in model parameters. In this study we show that individual differences in behavior from a novel perceptual decision ...

  10. Hazard personality profiles and individual differences

    International Nuclear Information System (INIS)

    Barnett, J.; Breakwell, G.M.

    1998-01-01

    Full text of publication follows: the dominance of the 'psychometric paradigm' and the consequent emphasis on identifying the qualities related to a hazard's perceived risk has resulted in little attention being given to individual variations in the acceptance of such 'personality profiles' of hazards. Attempts to locate sources of variability have largely focused on social, cultural and institutional factors (Turner and Wynne, 1992; Sjoeberg, 1995). Less attention has been paid to the role of intra-individual differences (Myers, Henderson-King, and Henderson-King, 1997). To address this, a questionnaire study (n = 172) explored the relationships between anxiety, experience and risk perceptions in relation to 16 risk activities. Different patterns of relationships for voluntary and involuntary activities were expected. Measures of experience included assessments of impact and outcome valence as well as frequency. Proclivity for, and likelihood of, future risk experiences were also assessed. The results revealed a number of relationships between individual difference variables and risk perceptions relating to the voluntariness of the activities. For involuntary risk activities, there were associations between the experience variables and risk ratings, e.g. previous experience of positive outcomes of involuntary risk activities is associated with perceptions of them affecting few people, with not being fatal and with known risk levels. This would suggest that taking into account people's previous experience of risks is likely to affect reactions to, and mediate the effectiveness of risk communications relating to involuntary risk activities. In contrast for voluntary activities it is the two 'future' oriented variables that are associated with risk perceptions. The relationship between anxiety and risk perceptions also varied in relation to the voluntariness of risk activities. The importance of incorporating a consideration of individual differences within

  11. Individual differences in multitasking ability and adaptability.

    Science.gov (United States)

    Morgan, Brent; D'Mello, Sidney; Abbott, Robert; Radvansky, Gabriel; Haass, Michael; Tamplin, Andrea

    2013-08-01

    The aim of this study was to identify the cognitive factors that predictability and adaptability during multitasking with a flight simulator. Multitasking has become increasingly prevalent as most professions require individuals to perform multiple tasks simultaneously. Considerable research has been undertaken to identify the characteristics of people (i.e., individual differences) that predict multitasking ability. Although working memory is a reliable predictor of general multitasking ability (i.e., performance in normal conditions), there is the question of whether different cognitive faculties are needed to rapidly respond to changing task demands (adaptability). Participants first completed a battery of cognitive individual differences tests followed by multitasking sessions with a flight simulator. After a baseline condition, difficulty of the flight simulator was incrementally increased via four experimental manipulations, and performance metrics were collected to assess multitasking ability and adaptability. Scholastic aptitude and working memory predicted general multitasking ability (i.e., performance at baseline difficulty), but spatial manipulation (in conjunction with working memory) was a major predictor of adaptability (performance in difficult conditions after accounting for baseline performance). Multitasking ability and adaptability may be overlapping but separate constructs that draw on overlapping (but not identical) sets of cognitive abilities. The results of this study are applicable to practitioners and researchers in human factors to assess multitasking performance in real-world contexts and with realistic task constraints. We also present a framework for conceptualizing multitasking adaptability on the basis of five adaptability profiles derived from performance on tasks with consistent versus increased difficulty.

  12. Intra-individual gait patterns across different time-scales as revealed by means of a supervised learning model using kernel-based discriminant regression.

    Directory of Open Access Journals (Sweden)

    Fabian Horst

    Full Text Available Traditionally, gait analysis has been centered on the idea of average behavior and normality. On one hand, clinical diagnoses and therapeutic interventions typically assume that average gait patterns remain constant over time. On the other hand, it is well known that all our movements are accompanied by a certain amount of variability, which does not allow us to make two identical steps. The purpose of this study was to examine changes in the intra-individual gait patterns across different time-scales (i.e., tens-of-mins, tens-of-hours.Nine healthy subjects performed 15 gait trials at a self-selected speed on 6 sessions within one day (duration between two subsequent sessions from 10 to 90 mins. For each trial, time-continuous ground reaction forces and lower body joint angles were measured. A supervised learning model using a kernel-based discriminant regression was applied for classifying sessions within individual gait patterns.Discernable characteristics of intra-individual gait patterns could be distinguished between repeated sessions by classification rates of 67.8 ± 8.8% and 86.3 ± 7.9% for the six-session-classification of ground reaction forces and lower body joint angles, respectively. Furthermore, the one-on-one-classification showed that increasing classification rates go along with increasing time durations between two sessions and indicate that changes of gait patterns appear at different time-scales.Discernable characteristics between repeated sessions indicate continuous intrinsic changes in intra-individual gait patterns and suggest a predominant role of deterministic processes in human motor control and learning. Natural changes of gait patterns without any externally induced injury or intervention may reflect continuous adaptations of the motor system over several time-scales. Accordingly, the modelling of walking by means of average gait patterns that are assumed to be near constant over time needs to be reconsidered in the

  13. Intra-individual gait patterns across different time-scales as revealed by means of a supervised learning model using kernel-based discriminant regression.

    Science.gov (United States)

    Horst, Fabian; Eekhoff, Alexander; Newell, Karl M; Schöllhorn, Wolfgang I

    2017-01-01

    Traditionally, gait analysis has been centered on the idea of average behavior and normality. On one hand, clinical diagnoses and therapeutic interventions typically assume that average gait patterns remain constant over time. On the other hand, it is well known that all our movements are accompanied by a certain amount of variability, which does not allow us to make two identical steps. The purpose of this study was to examine changes in the intra-individual gait patterns across different time-scales (i.e., tens-of-mins, tens-of-hours). Nine healthy subjects performed 15 gait trials at a self-selected speed on 6 sessions within one day (duration between two subsequent sessions from 10 to 90 mins). For each trial, time-continuous ground reaction forces and lower body joint angles were measured. A supervised learning model using a kernel-based discriminant regression was applied for classifying sessions within individual gait patterns. Discernable characteristics of intra-individual gait patterns could be distinguished between repeated sessions by classification rates of 67.8 ± 8.8% and 86.3 ± 7.9% for the six-session-classification of ground reaction forces and lower body joint angles, respectively. Furthermore, the one-on-one-classification showed that increasing classification rates go along with increasing time durations between two sessions and indicate that changes of gait patterns appear at different time-scales. Discernable characteristics between repeated sessions indicate continuous intrinsic changes in intra-individual gait patterns and suggest a predominant role of deterministic processes in human motor control and learning. Natural changes of gait patterns without any externally induced injury or intervention may reflect continuous adaptations of the motor system over several time-scales. Accordingly, the modelling of walking by means of average gait patterns that are assumed to be near constant over time needs to be reconsidered in the context of

  14. Digital Image Analysis of Yeast Single Cells Growing in Two Different Oxygen Concentrations to Analyze the Population Growth and to Assist Individual-Based Modeling.

    Science.gov (United States)

    Ginovart, Marta; Carbó, Rosa; Blanco, Mónica; Portell, Xavier

    2017-01-01

    Nowadays control of the growth of Saccharomyces to obtain biomass or cellular wall components is crucial for specific industrial applications. The general aim of this contribution is to deal with experimental data obtained from yeast cells and from yeast cultures to attempt the integration of the two levels of information, individual and population, to progress in the control of yeast biotechnological processes by means of the overall analysis of this set of experimental data, and to assist in the improvement of an individual-based model, namely, INDISIM- Saccha . Populations of S. cerevisiae growing in liquid batch culture, in aerobic and microaerophilic conditions, were studied. A set of digital images was taken during the population growth, and a protocol for the treatment and analyses of the images obtained was established. The piecewise linear model of Buchanan was adjusted to the temporal evolutions of the yeast populations to determine the kinetic parameters and changes of growth phases. In parallel, for all the yeast cells analyzed, values of direct morphological parameters, such as area, perimeter, major diameter, minor diameter, and derived ones, such as circularity and elongation, were obtained. Graphical and numerical methods from descriptive statistics were applied to these data to characterize the growth phases and the budding state of the yeast cells in both experimental conditions, and inferential statistical methods were used to compare the diverse groups of data achieved. Oxidative metabolism of yeast in a medium with oxygen available and low initial sugar concentration can be taken into account in order to obtain a greater number of cells or larger cells. Morphological parameters were analyzed statistically to identify which were the most useful for the discrimination of the different states, according to budding and/or growth phase, in aerobic and microaerophilic conditions. The use of the experimental data for subsequent modeling work was then

  15. Sensorimotor Learning: Neurocognitive Mechanisms and Individual Differences.

    Science.gov (United States)

    Seidler, R D; Carson, R G

    2017-07-13

    Here we provide an overview of findings and viewpoints on the mechanisms of sensorimotor learning presented at the 2016 Biomechanics and Neural Control of Movement (BANCOM) conference in Deer Creek, OH. This field has shown substantial growth in the past couple of decades. For example it is now well accepted that neural systems outside of primary motor pathways play a role in learning. Frontoparietal and anterior cingulate networks contribute to sensorimotor adaptation, reflecting strategic aspects of exploration and learning. Longer term training results in functional and morphological changes in primary motor and somatosensory cortices. Interestingly, re-engagement of strategic processes once a skill has become well learned may disrupt performance. Efforts to predict individual differences in learning rate have enhanced our understanding of the neural, behavioral, and genetic factors underlying skilled human performance. Access to genomic analyses has dramatically increased over the past several years. This has enhanced our understanding of cellular processes underlying the expression of human behavior, including involvement of various neurotransmitters, receptors, and enzymes. Surprisingly our field has been slow to adopt such approaches in studying neural control, although this work does require much larger sample sizes than are typically used to investigate skill learning. We advocate that individual differences approaches can lead to new insights into human sensorimotor performance. Moreover, a greater understanding of the factors underlying the wide range of performance capabilities seen across individuals can promote personalized medicine and refinement of rehabilitation strategies, which stand to be more effective than "one size fits all" treatments.

  16. Experimental Effects and Individual Differences in Linear Mixed Models: Estimating the Relationship between Spatial, Object, and Attraction Effects in Visual Attention

    Science.gov (United States)

    Kliegl, Reinhold; Wei, Ping; Dambacher, Michael; Yan, Ming; Zhou, Xiaolin

    2011-01-01

    Linear mixed models (LMMs) provide a still underused methodological perspective on combining experimental and individual-differences research. Here we illustrate this approach with two-rectangle cueing in visual attention (Egly et al., 1994). We replicated previous experimental cue-validity effects relating to a spatial shift of attention within an object (spatial effect), to attention switch between objects (object effect), and to the attraction of attention toward the display centroid (attraction effect), also taking into account the design-inherent imbalance of valid and other trials. We simultaneously estimated variance/covariance components of subject-related random effects for these spatial, object, and attraction effects in addition to their mean reaction times (RTs). The spatial effect showed a strong positive correlation with mean RT and a strong negative correlation with the attraction effect. The analysis of individual differences suggests that slow subjects engage attention more strongly at the cued location than fast subjects. We compare this joint LMM analysis of experimental effects and associated subject-related variances and correlations with two frequently used alternative statistical procedures. PMID:21833292

  17. Prospective memory, personality, and individual differences.

    Science.gov (United States)

    Uttl, Bob; White, Carmela A; Wong Gonzalez, Daniela; McDouall, Joanna; Leonard, Carrie A

    2013-01-01

    A number of studies investigating the relationship between personality and prospective memory (ProM) have appeared during the last decade. However, a review of these studies reveals little consistency in their findings and conclusions. To clarify the relationship between ProM and personality, we conducted two studies: a meta-analysis of prior research investigating the relationships between ProM and personality, and a study with 378 participants examining the relationships between ProM, personality, verbal intelligence, and retrospective memory. Our review of prior research revealed great variability in the measures used to assess ProM, and in the methodological quality of prior research; these two factors may partially explain inconsistent findings in the literature. Overall, the meta-analysis revealed very weak correlations (rs ranging from 0.09 to 0.10) between ProM and three of the Big Five factors: Openness, Conscientiousness, and Agreeableness. Our experimental study showed that ProM performance was related to individual differences such as verbal intelligence as well as to personality factors and that the relationship between ProM and personality factors depends on the ProM subdomain. In combination, the two studies suggest that ProM performance is relatively weakly related to personality factors and more strongly related to individual differences in cognitive factors.

  18. Individual differences in response conflict adaptations

    Directory of Open Access Journals (Sweden)

    Doris eKeye

    2013-12-01

    Full Text Available Conflict-monitoring theory argues for a general cognitive mechanism that monitors for con-flicts in information-processing. If that mechanism detects conflict, it engages cognitive con-trol to resolve it. A slow-down in response to incongruent trials (conflict effect, and a modu-lation of the conflict effect by the congruence of the preceding trial (Gratton or context effect have been taken as indicators of such a monitoring system. The present study (N = 157 investigated individual differences in the conflict and the context effect in a horizontal and a vertical Simon task, and their correlation with working memory capacity. Strength of conflict was varied by proportion of congruent trials. Coherent factors could be formed representing individual differences in speeded performance, conflict adaptation, and context adaptation. Conflict and context factors were not associated with each other. Contrary to theories assuming a close relation between working memory and cognitive control, working memory capacity showed no relation with any factors representing adaptation to conflict.

  19. Towards a Pedagogy for Clinical Education: Beyond Individual Learning Differences

    Science.gov (United States)

    Kinchin, Ian M.; Baysan, Aylin; Cabot, Lyndon Bruce

    2008-01-01

    The development of teaching in higher education towards a more learner-orientated model has been supported by the literature on individual learning differences and on learning styles in particular. This has contributed to the evolution of university pedagogy away from a medieval transmission model than runs counter to contemporary understanding of…

  20. Proprioception as a basis for individual differences

    Directory of Open Access Journals (Sweden)

    Liutsko, Ludmila N.

    2013-09-01

    Full Text Available In this chapter the author summarises the descriptions of proprioceptive sense from different perspectives. The importance of proprioceptive sense has been shown in developmental psychology, in both the earlier and later stages of individuum formation. The author emphasises in this chapter the role of proprioception as a basis of personality and the individual differences construct. The importance of assessing behaviour at multiple levels has been pointed out by experiments of classic and modern researchers that should include not only verbal tests that would be more important for conscious mental description, but also techniques that could assess other behavioural characteristics, including automatic unconscious and pre-reflexive behaviour. The author also describes the effects of altered proprioception in humans, such as the Pinocchio effect, and other spatial perception distortions. In this chapter the importance of proprioception in acquiring new skills (embodied knowledge as automatic and conditioned reflexive behaviour has also been highlighted. Finally, the complete picture of the individuum has been presented as a multi-layered level of a body-mind union approach.

  1. Individual differences in learning predict the return of fear.

    Science.gov (United States)

    Gershman, Samuel J; Hartley, Catherine A

    2015-09-01

    Using a laboratory analogue of learned fear (Pavlovian fear conditioning), we show that there is substantial heterogeneity across individuals in spontaneous recovery of fear following extinction training. We propose that this heterogeneity might stem from qualitative individual differences in the nature of extinction learning. Whereas some individuals tend to form a new memory during extinction, leaving their fear memory intact, others update the original threat association with new safety information, effectively unlearning the fear memory. We formalize this account in a computational model of fear learning and show that individuals who, according to the model, are more likely to form new extinction memories tend to show greater spontaneous recovery compared to individuals who appear to only update a single memory. This qualitative variation in fear and extinction learning may have important implications for understanding vulnerability and resilience to fear-related psychiatric disorders.

  2. Individual differences, cultural differences, and dialectic conflict description and resolution.

    Science.gov (United States)

    Kim, Kyungil; Markman, Arthur B

    2013-01-01

    Previous research suggests that members of East Asian cultures show a greater preference for dialectical thinking than do Westerners. This paper attempts to account for these differences in cognition using individual difference variables that may explain variation in performance both within and across cultures. Especially, we propose that the abovementioned cultural differences are rooted in a greater fear of isolation (FOI) in East Asians than in Westerners. To support this hypothesis, in Experiment 1, we manipulated FOI in American participants before having them resolve two conflicts: an interpersonal conflict and a conflict between an individual and an institution. We found that the Americans among whom a high level of FOI had been induced were more likely to look for a dialectical resolution than those among whom a low level had been prompted. The relationship between conflict resolution and FOI was further investigated in Experiment 2, in which FOI was not manipulated. The results indicated that Koreans had higher chronic FOI on average than did the Americans. Compared to the Americans, the Koreans were more likely to resolve the interpersonal conflict dialectically, but did not show the same bias in resolving the person-institution conflict. The differences in the preference for dialectical resolution between FOI conditions in Experiment 1 and cultural groups in Experiment 2 were mediated by FOI. These findings bolster previous research on FOI in showing that chronic levels of FOI are positively related to both preference for dialectical sentences and sensitivity to context. They provide clearer insight into how differences in FOI affect attention and thereby higher-level reasoning such as dialectic description and conflict resolution.

  3. Consistent individual differences in human social learning strategies.

    Science.gov (United States)

    Molleman, Lucas; van den Berg, Pieter; Weissing, Franz J

    2014-04-04

    Social learning has allowed humans to build up extensive cultural repertoires, enabling them to adapt to a wide variety of environmental and social conditions. However, it is unclear which social learning strategies people use, especially in social contexts where their payoffs depend on the behaviour of others. Here we show experimentally that individuals differ in their social learning strategies and that they tend to employ the same learning strategy irrespective of the interaction context. Payoff-based learners focus on their peers' success, while decision-based learners disregard payoffs and exclusively focus on their peers' past behaviour. These individual differences may be of considerable importance for cultural evolution. By means of a simple model, we demonstrate that groups harbouring individuals with different learning strategies may be faster in adopting technological innovations and can be more efficient through successful role differentiation. Our study highlights the importance of individual variation for human interactions and sheds new light on the dynamics of cultural evolution.

  4. Bivalves: From individual to population modelling

    Science.gov (United States)

    Saraiva, S.; van der Meer, J.; Kooijman, S. A. L. M.; Ruardij, P.

    2014-11-01

    An individual based population model for bivalves was designed, built and tested in a 0D approach, to simulate the population dynamics of a mussel bed located in an intertidal area. The processes at the individual level were simulated following the dynamic energy budget theory, whereas initial egg mortality, background mortality, food competition, and predation (including cannibalism) were additional population processes. Model properties were studied through the analysis of theoretical scenarios and by simulation of different mortality parameter combinations in a realistic setup, imposing environmental measurements. Realistic criteria were applied to narrow down the possible combination of parameter values. Field observations obtained in the long-term and multi-station monitoring program were compared with the model scenarios. The realistically selected modeling scenarios were able to reproduce reasonably the timing of some peaks in the individual abundances in the mussel bed and its size distribution but the number of individuals was not well predicted. The results suggest that the mortality in the early life stages (egg and larvae) plays an important role in population dynamics, either by initial egg mortality, larvae dispersion, settlement failure or shrimp predation. Future steps include the coupling of the population model with a hydrodynamic and biogeochemical model to improve the simulation of egg/larvae dispersion, settlement probability, food transport and also to simulate the feedback of the organisms' activity on the water column properties, which will result in an improvement of the food quantity and quality characterization.

  5. Modeling Individual Cyclic Variation in Human Behavior.

    Science.gov (United States)

    Pierson, Emma; Althoff, Tim; Leskovec, Jure

    2018-04-01

    Cycles are fundamental to human health and behavior. Examples include mood cycles, circadian rhythms, and the menstrual cycle. However, modeling cycles in time series data is challenging because in most cases the cycles are not labeled or directly observed and need to be inferred from multidimensional measurements taken over time. Here, we present Cyclic Hidden Markov Models (CyH-MMs) for detecting and modeling cycles in a collection of multidimensional heterogeneous time series data. In contrast to previous cycle modeling methods, CyHMMs deal with a number of challenges encountered in modeling real-world cycles: they can model multivariate data with both discrete and continuous dimensions; they explicitly model and are robust to missing data; and they can share information across individuals to accommodate variation both within and between individual time series. Experiments on synthetic and real-world health-tracking data demonstrate that CyHMMs infer cycle lengths more accurately than existing methods, with 58% lower error on simulated data and 63% lower error on real-world data compared to the best-performing baseline. CyHMMs can also perform functions which baselines cannot: they can model the progression of individual features/symptoms over the course of the cycle, identify the most variable features, and cluster individual time series into groups with distinct characteristics. Applying CyHMMs to two real-world health-tracking datasets-of human menstrual cycle symptoms and physical activity tracking data-yields important insights including which symptoms to expect at each point during the cycle. We also find that people fall into several groups with distinct cycle patterns, and that these groups differ along dimensions not provided to the model. For example, by modeling missing data in the menstrual cycles dataset, we are able to discover a medically relevant group of birth control users even though information on birth control is not given to the model.

  6. Individual Differences in Online Spoken Word Recognition: Implications for SLI

    Science.gov (United States)

    McMurray, Bob; Samelson, Vicki M.; Lee, Sung Hee; Tomblin, J. Bruce

    2010-01-01

    Thirty years of research has uncovered the broad principles that characterize spoken word processing across listeners. However, there have been few systematic investigations of individual differences. Such an investigation could help refine models of word recognition by indicating which processing parameters are likely to vary, and could also have…

  7. Individual differences in personality change across the adult life span.

    Science.gov (United States)

    Schwaba, Ted; Bleidorn, Wiebke

    2018-06-01

    A precise and comprehensive description of personality continuity and change across the life span is the bedrock upon which theories of personality development are built. Little research has quantified the degree to which individuals deviate from mean-level developmental trends. In this study, we addressed this gap by examining individual differences in personality trait change across the life span. Data came from a nationally representative sample of 9,636 Dutch participants who provided Big Five self-reports at five assessment waves across 7 years. We divided our sample into 14 age groups (ages 16-84 at initial measurement) and estimated latent growth curve models to describe individual differences in personality change across the study period for each trait and age group. Across the adult life span, individual differences in personality change were small but significant until old age. For Openness, Conscientiousness, Extraversion, and Agreeableness, individual differences in change were most pronounced in emerging adulthood and decreased throughout midlife and old age. For Emotional Stability, individual differences in change were relatively consistent across the life span. These results inform theories of life span development and provide future directions for research on the causes and conditions of personality change. © 2017 Wiley Periodicals, Inc.

  8. Feasibility of Using Individual Differences in Emotionality as Predictors of Job Performance

    National Research Council Canada - National Science Library

    Arvey, Richard

    1998-01-01

    .... Third, the authors develop a model of how individual differences in emotional expression, combined with organizational, occupational and job demands, influence the way individuals react to triggering...

  9. Affect intensity and individual differences in informational style.

    Science.gov (United States)

    Larsen, R J; Billings, D W; Cutler, S E

    1996-03-01

    Although individuals differ widely in the typical intensity of their affective experience, the mechanisms that create or maintain these differences are unclear. Larsen, Diener, and Cropanzano (1987) examined the hypothesis that individual differences in affect intensity (AI) are related to how people interpret emotional stimuli. They found that high AI individuals engaged in more personalizing and generalizing cognitions while construing emotional stimuli than low AI individuals. The present study extends these findings by examining cognitive activity during a different task-the generation of information to communicate about life events. Participants provided free-response descriptions of 16 life events. These descriptions were content coded for five informational style variables. It was found that the descriptive information generated by high AI participants contained significantly more references to emotional arousal, more focus on feelings, and more generalization compared to participants low in AI. These results are consistent with the notion that specific cognitive activity may lead to, or at least be associated with, dispositional affect intensity. In addition, the informational style variables identified in this study were stable over time and consistent across situations. Although men and women differ in AI, this difference becomes insignificant after controlling for informational style variation. Overall results are discussed in terms of a model of various psychological mechanisms that may potentially create or maintain individual differences in affect intensity.

  10. Fertility desires and unmet need for family planning among HIV infected individuals in two HIV clinics with differing models of family planning service delivery.

    Science.gov (United States)

    Wanyenze, Rhoda K; Matovu, Joseph K B; Kamya, Moses R; Tumwesigye, Nazarius M; Nannyonga, Maria; Wagner, Glenn J

    2015-01-28

    Eliminating family planning (FP) unmet need among HIV-infected individuals (PLHIV) is critical to elimination of mother-to-child HIV transmission. We assessed FP unmet need among PLHIV attending two clinics with differing models of FP services. Nsambya Home Care provided only FP information while Mulago HIV clinic provided information and contraceptives onsite. In a cross-sectional study conducted between February-June 2011, we documented pregnancies, fertility desires, and contraceptive use among 797 HIV-infected men and women (408 in Mulago and 389 in Nsambya). FP unmet need was calculated among women who were married, unmarried but had sex within the past month, did not desire the last or future pregnancy at all or wished to postpone for ≥ two years and were not using contraceptives. Multivariable analyses for correlates of FP unmet need were computed for each clinic. Overall, 40% (315) had been pregnant since HIV diagnosis; 58% desired the pregnancies. Of those who were not pregnant, 49% (366) did not desire more children at all; 15.7% wanted children then and 35.3% later. The unmet need for FP in Nsambya (45.1%) was significantly higher than that in Mulago at 30.9% (p = 0.008). Age 40+ compared to 18-29 years (OR = 6.05; 95% CI: 1.69, 21.62 in Mulago and OR = 0.21; 95% CI: 0.05, 0.90 in Nsambya), other Christian denominations (Pentecostal and Seventh Day Adventists) compared to Catholics (OR = 7.18; 95% CI: 2.14, 24.13 in Mulago and OR = 0.23; 95% CI: 0.06, 0.80 in Nsambya), and monthly expenditure > USD 200 compared to fertility support and elimination of FP unmet need among PLHIV, even with integration of FP information and supplies into HIV clinics.

  11. Exploring Individual Differences in Preschoolers' Causal Stance

    Science.gov (United States)

    Alvarez, Aubry; Booth, Amy E.

    2016-01-01

    Preschoolers, as a group, are highly attuned to causality, and this attunement is known to facilitate memory, learning, and problem solving. However, recent work reveals substantial individual variability in the strength of children's "causal stance," as demonstrated by their curiosity about and preference for new causal information. In…

  12. Individual differences in attention influence perceptual decision making.

    Science.gov (United States)

    Nunez, Michael D; Srinivasan, Ramesh; Vandekerckhove, Joachim

    2015-01-01

    Sequential sampling decision-making models have been successful in accounting for reaction time (RT) and accuracy data in two-alternative forced choice tasks. These models have been used to describe the behavior of populations of participants, and explanatory structures have been proposed to account for between individual variability in model parameters. In this study we show that individual differences in behavior from a novel perceptual decision making task can be attributed to (1) differences in evidence accumulation rates, (2) differences in variability of evidence accumulation within trials, and (3) differences in non-decision times across individuals. Using electroencephalography (EEG), we demonstrate that these differences in cognitive variables, in turn, can be explained by attentional differences as measured by phase-locking of steady-state visual evoked potential (SSVEP) responses to the signal and noise components of the visual stimulus. Parameters of a cognitive model (a diffusion model) were obtained from accuracy and RT distributions and related to phase-locking indices (PLIs) of SSVEPs with a single step in a hierarchical Bayesian framework. Participants who were able to suppress the SSVEP response to visual noise in high frequency bands were able to accumulate correct evidence faster and had shorter non-decision times (preprocessing or motor response times), leading to more accurate responses and faster response times. We show that the combination of cognitive modeling and neural data in a hierarchical Bayesian framework relates physiological processes to the cognitive processes of participants, and that a model with a new (out-of-sample) participant's neural data can predict that participant's behavior more accurately than models without physiological data.

  13. Exploring Individual Differences in Workload Assessment

    Science.gov (United States)

    2014-12-26

    recall their workload accurately. However, it has been shown that the bias shown in subjective ratings can actually provide insight into significant...or subconsciously and embark on load shedding, postponing a task to permit another decision action to be completed in a required timeframe (Smith...or slow heart rate or unique physiological measure will not add unnecessary bias to the data. Individual baseline measures are typically taken at the

  14. Individual differences in attention influence perceptual decision making

    Directory of Open Access Journals (Sweden)

    Michael Dawson Nunez

    2015-02-01

    Full Text Available Sequential sampling decision-making models have been successful in accounting for reactiontime (RT and accuracy data in two-alternative forced choice tasks. These models have beenused to describe the behavior of populations of participants, and explanatory structures havebeen proposed to account for between individual variability in model parameters. In this studywe show that individual differences in behavior from a novel perceptual decision making taskcan be attributed to 1 differences in evidence accumulation rates, 2 differences in variability ofevidence accumulation within trials, and 3 differences in non-decision times across individuals.Using electroencephalography (EEG, we demonstrate that these differences in cognitivevariables, in turn, can be explained by attentional differences as measured by phase-lockingof steady-state visual evoked potential (SSVEP responses to the signal and noise componentsof the visual stimulus. Parameters of a cognitive model (a diffusion model were obtained fromaccuracy and RT distributions and related to phase-locking indices (PLIs of SSVEPs with asingle step in a hierarchical Bayesian framework. Participants who were able to suppress theSSVEP response to visual noise in high frequency bands were able to accumulate correctevidence faster and had shorter non-decision times (preprocessing or motor response times,leading to more accurate responses and faster response times. We show that the combinationof cognitive modeling and neural data in a hierarchical Bayesian framework relates physiologicalprocesses to the cognitive processes of participants, and that a model with a new (out-of-sample participant’s neural data can predict that participant’s behavior more accurately thanmodels without physiological data.

  15. Individual differences in attention during category learning

    NARCIS (Netherlands)

    Lee, M.D.; Wetzels, R.

    2010-01-01

    A central idea in many successful models of category learning—including the Generalized Context Model (GCM)—is that people selectively attend to those dimensions of stimuli that are relevant for dividing them into categories. We use the GCM to re-examine some previously analyzed category learning

  16. Impact of Individual Differences on Reliance Optimization

    Science.gov (United States)

    2016-05-31

    Contemporary dimensional models of fatigue differentiate a variety of components including acute and chronic fatigue, and emotional , motivational and...which differentiates fundamental state dimensions of task engagement (energy, concentration, task motivation), distress (negative mood, lack of...demonstrated to be positively associated with a range of sensory, perceptual , and attentional abilities that contribute to performance on tasks requiring

  17. Culture, morality and individual differences: comparability and incomparability across species.

    Science.gov (United States)

    Saucier, Gerard

    2018-04-19

    Major routes to identifying individual differences (in diverse species) include studies of behaviour patterns as represented in language and neurophysiology. But results from these approaches appear not to converge on some major dimensions. Identifying dimensions of human variation least applicable to non-human species may help to partition human-specific individual differences of recent evolutionary origin from those shared across species. Human culture includes learned, enforced social-norm systems that are symbolically reinforced and referenced in displays signalling adherence. At a key juncture in human evolution bullying aggression and deception-based cheating apparently became censured in the language of a moral community, enabling mutual observation coordinated in gossip, associated with external sanctions. That still-conserved cultural paradigm moralistically regulates selfish advantage-taking, with shared semantics and explicit rules. Ethics and moral codes remain critical and universal components of human culture and have a stronger imprint in language than most aspects of the currently popular Big-Five taxonomy, a model that sets out five major lines of individual-differences variation in human personality. In other species (e.g. chimpanzees), human observers might see apparent individual differences in morality-relevant traits, but not because the animals have human-analogue sanctioning systems. Removing the moral dimension of personality and other human-specific manifestations (e.g. religion) may aid in identifying those other bases of individual differences more ubiquitous across species.This article is part of the theme issue 'Diverse perspectives on diversity: multi-disciplinary approaches to taxonomies of individual differences'. © 2018 The Author(s).

  18. Accounting for individual differences in human associative learning.

    Science.gov (United States)

    Byrom, Nicola C

    2013-09-04

    Associative learning has provided fundamental insights to understanding psychopathology. However, psychopathology occurs along a continuum and as such, identification of disruptions in processes of associative learning associated with aspects of psychopathology illustrates a general flexibility in human associative learning. A handful of studies have looked specifically at individual differences in human associative learning, but while much work has concentrated on accounting for flexibility in learning caused by external factors, there has been limited work considering how to model the influence of dispositional factors. This review looks at the range of individual differences in human associative learning that have been explored and the attempts to account for, and model, this flexibility. To fully understand human associative learning, further research needs to attend to the causes of variation in human learning.

  19. Accounting for Individual Differences in Human Associative Learning.

    Directory of Open Access Journals (Sweden)

    Nicola C Byrom

    2013-09-01

    Full Text Available Associative learning has provided fundamental insights to understanding psychopathology. However, psychopathology occurs along a continuum and as such, identification of disruptions in processes of associative learning associated with aspects of psychopathology illustrates a general flexibility in human associative learning. A handful of studies have looked specifically at individual differences in human associative learning, but while much work has concentrated on accounting for flexibility in learning caused by external factors, there has been limited work considering how to model the influence of dispositional factors. This review looks at the range of individual differences in human associative learning that have been explored and the attempts to account for, and model, this flexibility. To fully understand human associative learning, further research needs to attend to the causes of variation in human learning.

  20. Differences Between Individual and Societal Health State Valuations

    Science.gov (United States)

    Chapman, Benjamin P.; Franks, Peter; Duberstein, Paul R.; Jerant, Anthony

    2009-01-01

    Objective The concept of “adaptation” has been proposed to account for differences between individual and societal valuations of specific health states in patients with chronic diseases. Little is known about psychological indices of adaptational capacity, which may predict differences in individual and societal valuations of health states. We investigated whether such differences were partially explained by personality traits in chronic disease patients. Research Design Analysis of baseline data of randomized controlled trial. Subjects Three hundred seventy patients with chronic disease. Measures The NEO-five factor inventory measure of personality, EuroQoL-5D (EQ-5D) societal-based, and the EQ visual analogue scale individually-based measures of health valuation. Results Regression analyses modeled Dev, a measure of difference between the EQ-Visual Analogue Scale and EQ-5D, as a function of personality traits, sociodemographic factors, and chronic diseases. Individual valuations were significantly and clinically higher than societal valuations among patients in the second and third quartile of conscientiousness (Dev = 0.08, P = 0.01); among covariates, only depression (Dev = -0.04, P = 0.046) was also associated with Dev. Conclusion Compared with societal valuations of a given health state, persons at higher quartiles of conscientiousness report less disutility associated with poor health. The effect is roughly twice that of some estimates of minimally important clinical differences on the EQ-5D and of depression. Although useful at the aggregate level, societal preference measures may systematically undervalue the health states of more conscientious individuals. Future work should examine the impact this has on individual patient outcome evaluation in clinical studies. PMID:19543121

  1. Chimpanzees demonstrate individual differences in social information use.

    Science.gov (United States)

    Watson, Stuart K; Vale, Gillian L; Hopper, Lydia M; Dean, Lewis G; Kendal, Rachel L; Price, Elizabeth E; Wood, Lara A; Davis, Sarah J; Schapiro, Steven J; Lambeth, Susan P; Whiten, Andrew

    2018-06-19

    Studies of transmission biases in social learning have greatly informed our understanding of how behaviour patterns may diffuse through animal populations, yet within-species inter-individual variation in social information use has received little attention and remains poorly understood. We have addressed this question by examining individual performances across multiple experiments with the same population of primates. We compiled a dataset spanning 16 social learning studies (26 experimental conditions) carried out at the same study site over a 12-year period, incorporating a total of 167 chimpanzees. We applied a binary scoring system to code each participant's performance in each study according to whether they demonstrated evidence of using social information from conspecifics to solve the experimental task or not (Social Information Score-'SIS'). Bayesian binomial mixed effects models were then used to estimate the extent to which individual differences influenced SIS, together with any effects of sex, rearing history, age, prior involvement in research and task type on SIS. An estimate of repeatability found that approximately half of the variance in SIS was accounted for by individual identity, indicating that individual differences play a critical role in the social learning behaviour of chimpanzees. According to the model that best fit the data, females were, depending on their rearing history, 15-24% more likely to use social information to solve experimental tasks than males. However, there was no strong evidence of an effect of age or research experience, and pedigree records indicated that SIS was not a strongly heritable trait. Our study offers a novel, transferable method for the study of individual differences in social learning.

  2. Regional Differences in Demand for Coal as A Basis for Development of A Product Distribution Model for Mining Companies in the Individual Customers Segment

    Science.gov (United States)

    Magda, Roman; Bogacz, Paweł; Franik, Tadeusz; Celej, Maciej; Migza, Marcin

    2014-10-01

    The article presents a proposal of methodology based on the process of relationship marketing, serving to determine the level of demand for coal in the individual customer segment, as well as fuel distribution model for this customer group in Poland developed on the basis of this methodology. It also includes selected results of tests carried out using the proposed methods. These proposals have been defined on the basis of market capacity indicators, which can be determined for the district level based on data from the Polish Central Statistical Office. The study also included the use of linear programming, based on the cost of coal logistics, data concerning railway, road and storage infrastructure present on the Polish market and taking into account the legal aspects. The presented results may provide a basis for mining companies to develop a system of coal distribution management in the locations with the highest demand values.

  3. Emotion perception and empathy: An individual differences test of relations.

    Science.gov (United States)

    Olderbak, Sally; Wilhelm, Oliver

    2017-10-01

    Numerous theories posit a positive relation between perceiving emotion expressed in the face of a stranger (emotion perception) and feeling or cognitively understanding the emotion of that person (affective and cognitive empathy, respectively). However, when relating individual differences in emotion perception with individual differences in affective or cognitive empathy, effect sizes are contradictory, but often not significantly different from zero. Based on 4 studies (study ns range from 97 to 486 persons; n total = 958) that differ from one another on many design and sample characteristics, applying advanced modeling techniques to control for measurement error, we estimate relations between affective empathy, cognitive empathy, and emotion perception. Relations are tested separately for each of the 6 basic emotions (an emotion-specific model) as well as across all emotions (an emotion-general model). Reflecting the literature, effect sizes and statistical significance with an emotion-general model vary across the individual studies (rs range from -.001 to .24 for emotion perception with affective empathy and -.01 to .39 for emotion perception with cognitive empathy), with a meta-analysis of these results indicating emotion perception is weakly related with affective (r = .13, p = .003) and cognitive empathy (r = .13, p = .05). Relations are not strengthened in an emotion-specific model. We argue that the weak effect sizes and inconsistency across studies reflects a neglected distinction of measurement approach-specifically, empathy is assessed as typical behavior and emotion perception is assessed as maximal effort-and conclude with considerations regarding the measurement of each construct. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

  4. Individual differences in long-range time representation.

    Science.gov (United States)

    Agostino, Camila S; Caetano, Marcelo S; Balci, Fuat; Claessens, Peter M E; Zana, Yossi

    2017-04-01

    On the basis of experimental data, long-range time representation has been proposed to follow a highly compressed power function, which has been hypothesized to explain the time inconsistency found in financial discount rate preferences. The aim of this study was to evaluate how well linear and power function models explain empirical data from individual participants tested in different procedural settings. The line paradigm was used in five different procedural variations with 35 adult participants. Data aggregated over the participants showed that fitted linear functions explained more than 98% of the variance in all procedures. A linear regression fit also outperformed a power model fit for the aggregated data. An individual-participant-based analysis showed better fits of a linear model to the data of 14 participants; better fits of a power function with an exponent β > 1 to the data of 12 participants; and better fits of a power function with β discount rates in intertemporal choice to the compressed nature of subjective time must entail the characterization of subjective time on an individual-participant basis.

  5. Individual differences and the development of perceived control.

    Science.gov (United States)

    Skinner, E A; Zimmer-Gembeck, M J; Connell, J P

    1998-01-01

    Research on individual differences demonstrates that children's perceived control exerts a strong effect on their academic achievement and that, in turn, children's actual school performance influences their sense of control. At the same time, developmental research shows systematic age-graded changes in the processes that children use to regulate and interpret control experiences. Drawing on both these perspectives, the current study examines (1) age differences in the operation of beliefs-performance cycles and (2) the effects of these cycles on the development of children's perceived control and classroom engagement from the third to the seventh grade. Longitudinal data on about 1,600 children were collected six times (every fall and spring) over 3 consecutive school years, including children's reports of their perceived control and individual interactions with teachers; teachers' reports of each student's engagement in class; and, for a subset of students, grades and achievement tests. Analyses of individual differences and individual growth curves (estimated using hierarchical linear modeling procedures) were consistent, not only with a cyclic model of context, self, action, and outcomes, but also with predictors of individual development over 5 years from grade 3 to grade 7. Children who experienced teachers as warm and contingent were more likely to develop optimal profiles of control; these beliefs supported more active engagement in the classroom, resulting in better academic performance; success in turn predicted the maintenance of optimistic beliefs about the effectiveness of effort. In contrast, children who experienced teachers as unsupportive were more likely to develop beliefs that emphasized external causes; these profiles of control predicted escalating classroom disaffection and lower scholastic achievement; in turn, these poor performances led children to increasingly doubt their own capacities and to believe even more strongly in the power of

  6. Hypothermia in neonatal piglets: Interactions and causes of individual differences

    DEFF Research Database (Denmark)

    Kammersgaard, Trine S; Pedersen, Lene Juul; Jørgensen, Erik

    2011-01-01

    Hypothermia is a major cause of mortality in neonatal piglets. However, there are considerable individual differences in the successful recovery from postnatal hypothermia in the common farrowing environment, and so far the causes and interactions of causes have not been studied in detail. Using...... 635 crossbred neonatal piglets, the aim of this study was to identify the links among different physiological and behavioral measures and their connections to the piglets’ ability to overcome initial postnatal hypothermia, with rectal temperature at 2 h as the response variable. The data included......: birth weight, hypoxia at birth (viability score and lactate in umbilical cord blood), latency to first udder contact and first suckle, scans of individual piglet position during the first 2 h after birth, and rectal temperature at birth and 2 h post partum. A graphical chain model was used to analyze...

  7. Subjective workload and individual differences in information processing abilities

    Science.gov (United States)

    Damos, D. L.

    1984-01-01

    This paper describes several experiments examining the source of individual differences in the experience of mental workload. Three sources of such differences were examined: information processing abilities, timesharing abilities, and personality traits/behavior patterns. On the whole, there was little evidence that individual differences in information processing abilities or timesharing abilities are related to perceived differences in mental workload. However, individuals with strong Type A coronary prone behavior patterns differed in both single- and multiple-task performance from individuals who showed little evidence of such a pattern. Additionally, individuals with a strong Type A pattern showed some dissociation between objective performance and the experience of mental workload.

  8. Predicting Smartphone Operating System from Personality and Individual Differences.

    Science.gov (United States)

    Shaw, Heather; Ellis, David A; Kendrick, Libby-Rae; Ziegler, Fenja; Wiseman, Richard

    2016-12-01

    Android and iPhone devices account for over 90 percent of all smartphones sold worldwide. Despite being very similar in functionality, current discourse and marketing campaigns suggest that key individual differences exist between users of these two devices; however, this has never been investigated empirically. This is surprising, as smartphones continue to gain momentum across a variety of research disciplines. In this article, we consider if individual differences exist between these two distinct groups. In comparison to Android users, we found that iPhone owners are more likely to be female, younger, and increasingly concerned about their smartphone being viewed as a status object. Key differences in personality were also observed with iPhone users displaying lower levels of Honesty-Humility and higher levels of emotionality. Following this analysis, we were also able to build and test a model that predicted smartphone ownership at above chance level based on these individual differences. In line with extended self-theory, the type of smartphone owned provides some valuable information about its owner. These findings have implications for the increasing use of smartphones within research particularly for those working within Computational Social Science and PsychoInformatics, where data are typically collected from devices and applications running a single smartphone operating system.

  9. Individual differences in metacontrast masking regarding sensitivity and response bias.

    Science.gov (United States)

    Albrecht, Thorsten; Mattler, Uwe

    2012-09-01

    In metacontrast masking target visibility is modulated by the time until a masking stimulus appears. The effect of this temporal delay differs across participants in such a way that individual human observers' performance shows distinguishable types of masking functions which remain largely unchanged for months. Here we examined whether individual differences in masking functions depend on different response criteria in addition to differences in discrimination sensitivity. To this end we reanalyzed previously published data and conducted a new experiment for further data analyses. Our analyses demonstrate that a distinction of masking functions based on the type of masking stimulus is superior to a distinction based on the target-mask congruency. Individually different masking functions are based on individual differences in discrimination sensitivities and in response criteria. Results suggest that individual differences in metacontrast masking result from individually different criterion contents. Copyright © 2012 Elsevier Inc. All rights reserved.

  10. Individual difference predictors of change in career adaptability over time

    NARCIS (Netherlands)

    Zacher, Hannes

    Career adaptability is a psychosocial construct that reflects individuals' resources for managing career tasks and challenges. This study investigated the effects of demographic characteristics and three sets of individual difference variables (Big Five personality traits, core self-evaluations, and

  11. The role of scripts in personal consistency and individual differences.

    Science.gov (United States)

    Demorest, Amy; Popovska, Ana; Dabova, Milena

    2012-02-01

    This article examines the role of scripts in personal consistency and individual differences. Scripts are personally distinctive rules for understanding emotionally significant experiences. In 2 studies, scripts were identified from autobiographical memories of college students (Ns = 47 and 50) using standard categories of events and emotions to derive event-emotion compounds (e.g., Affiliation-Joy). In Study 1, scripts predicted responses to a reaction-time task 1 month later, such that participants responded more quickly to the event from their script when asked to indicate what emotion would be evoked by a series of events. In Study 2, individual differences in 5 common scripts were found to be systematically related to individual differences in traits of the Five-Factor Model. Distinct patterns of correlation revealed the importance of studying events and emotions in compound units, that is, in script form (e.g., Agreeableness was correlated with the script Affiliation-Joy but not with the scripts Fun-Joy or Affiliation-Love). © 2012 The Authors. Journal of Personality © 2012, Wiley Periodicals, Inc.

  12. Habituation in acoustic startle reflex: individual differences in personality.

    Science.gov (United States)

    Blanch, Angel; Balada, Ferran; Aluja, Anton

    2014-03-01

    This study analyzed the relationship of individual differences in personality with habituation in the acoustic startle response (ASR). Data from nine trials in ASR to white noise bursts and a personality questionnaire based on the alternative big five personality approach were modelled with a latent growth curve (LCM) including intercept and slope habituation growth factors. There was a negative correlation between the intercept and slope, indicating that individuals with higher initial ASR levels had also a more pronounced and faster decrease in the ASR. Contrary to expectations, Extraversion and Sensation Seeking did not relate with habituation in ASR. Neuroticism and Aggressiveness related asymmetrically with the habituation rate in ASR. Higher levels of Neuroticism were related with faster habituation, whereas higher levels of Aggressiveness were related with slower habituation. Further studies with the LCM should be undertaken to clarify in a greater extent the association of personality with habituation in ASR. Copyright © 2014 Elsevier B.V. All rights reserved.

  13. Individual Differences in Animal Stress Models: Considering Resilience, Vulnerability, and the Amygdala in Mediating the Effects of Stress and Conditioned Fear on Sleep.

    Science.gov (United States)

    Wellman, Laurie L; Fitzpatrick, Mairen E; Hallum, Olga Y; Sutton, Amy M; Williams, Brook L; Sanford, Larry D

    2016-06-01

    To examine the REM sleep response to stress and fearful memories as a potential marker of stress resilience and vulnerability and to assess the role of the basolateral amygdala (BLA) in mediating the effects of fear memory on sleep. Outbred Wistar rats were surgically implanted with electrodes for recording EEG and EMG and with bilateral guide cannulae directed at the BLA. Data loggers were placed intraperitoneally to record core body temperature. After recovery from surgery, the rats received shock training (ST: 20 footshocks, 0.8 mA, 0.5-s duration, 60-s interstimulus interval) and afterwards received microinjections of the GABAA agonist muscimol (MUS; 1.0 μM) to inactivate BLA or microinjections of vehicle (VEH) alone. Subsequently, the rats were separated into 4 groups (VEH-vulnerable (VEH-Vul; n = 14), VEH-resilient (VEH-Res; n = 13), MUS-vulnerable (MUS-Vul; n = 8), and MUS-resilient (MUS-Res; n = 11) based on whether or not REM was decreased, compared to baseline, during the first 4 h following ST. We then compared sleep, freezing, and the stress response (stress-induced hyperthermia, SIH) across groups to determine the effects of ST and fearful context re-exposure alone (CTX). REM was significantly reduced on the ST day in both VEH-Vul and MUS-Vul rats; however, post-ST MUS blocked the reduction in REM on the CTX day in the MUS-Vul group. The VEH-Res and MUS-Res rats showed similar levels of REM on both ST and CTX days. The effects of post-ST inactivation of BLA on freezing and SIH were minimal. Outbred Wistar rats can show significant individual differences in the effects of stress on REM that are mediated by BLA. These differences in REM can be independent of behavioral fear and the peripheral stress response, and may be an important biomarker of stress resilience and vulnerability. © 2016 Associated Professional Sleep Societies, LLC.

  14. Individual differences in the gesture effect on working memory.

    Science.gov (United States)

    Marstaller, Lars; Burianová, Hana

    2013-06-01

    Co-speech gestures have been shown to interact with working memory (WM). However, no study has investigated whether there are individual differences in the effect of gestures on WM. Combining a novel gesture/no-gesture task and an operation span task, we examined the differences in WM accuracy between individuals who gestured and individuals who did not gesture in relation to their WM capacity. Our results showed individual differences in the gesture effect on WM. Specifically, only individuals with low WM capacity showed a reduced WM accuracy when they did not gesture. Individuals with low WM capacity who did gesture, as well as high-capacity individuals (irrespective of whether they gestured or not), did not show the effect. Our findings show that the interaction between co-speech gestures and WM is affected by an individual's WM load.

  15. Localizing age-related individual differences in a hierarchical structure

    OpenAIRE

    Salthouse, Timothy A.

    2004-01-01

    Data from 33 separate studies were combined to create an aggregate data set consisting of 16 cognitive variables and 6832 different individuals who ranged between 18 and 95 years of age. Analyses were conducted to determine where in a hierarchical structure of cognitive abilities individual differences associated with age, gender, education, and self-reported health could be localized. The results indicated that each type of individual difference characteristic exhibited a d...

  16. Inter-individual Differences in Heart Rate Variability Are Associated with Inter-individual Differences in Empathy and Alexithymia

    Directory of Open Access Journals (Sweden)

    Alexander Lischke

    2018-02-01

    Full Text Available In the present study, we investigated whether inter-individual differences in vagally mediated heart rate variability (vmHRV would be associated with inter-individual differences in empathy and alexithymia. To this end, we determined resting state HF-HRV in 90 individuals that also completed questionnaires assessing inter-individual differences in empathy and alexithymia. Our categorical and dimensional analyses revealed that inter-individual differences in HF-HRV were differently associated with inter-individual differences in empathy and alexithymia. We found that individuals with high HF-HRV reported more empathy and less alexithymia than individuals with low HF-HRV. Moreover, we even found that an increase in HF-HRV was associated with an increase in empathy and a decrease in alexithymia across all participants. Taken together, these findings indicate that individuals with high HF-HRV are more empathetic and less alexithymic than individuals with low HF-HRV. These differences in empathy and alexithymia may explain why individuals with high HF-HRV are more successful in sharing and understanding the mental and emotional states of others than individuals with low HF-HRV.

  17. Bivalves: From individual to population modelling

    NARCIS (Netherlands)

    Saraiva, S.; van der Meer, J.; Kooijman, S.A.L.M.

    2014-01-01

    An individual based population model for bivalves was designed, built and tested in a 0D approach, to simulate the population dynamics of a mussel bed located in an intertidal area. The processes at the individual level were simulated following the dynamic energy budget theory, whereas initial egg

  18. Individual-based modeling of ecological and evolutionary processes

    NARCIS (Netherlands)

    DeAngelis, D.L.; Mooij, W.M.

    2005-01-01

    Individual-based models (IBMs) allow the explicit inclusion of individual variation in greater detail than do classical differential and difference equation models. Inclusion of such variation is important for continued progress in ecological and evolutionary theory. We provide a conceptual basis

  19. Trajectories and models of individual growth

    Directory of Open Access Journals (Sweden)

    Arseniy Karkach

    2006-11-01

    Full Text Available It has long been recognized that the patterns of growth play an important role in the evolution of age trajectories of fertility and mortality (Williams, 1957. Life history studies would benefit from a better understanding of strategies and mechanisms of growth, but still no comparative research on individual growth strategies has been conducted. Growth patterns and methods have been shaped by evolution and a great variety of them are observed. Two distinct patterns - determinate and indeterminate growth - are of a special interest for these studies since they present qualitatively different outcomes of evolution. We attempt to draw together studies covering growth in plant and animal species across a wide range of phyla focusing primarily on the noted qualitative features. We also review mathematical descriptions of growth, namely empirical growth curves and growth models, and discuss the directions of future research.

  20. Neural correlates of individual differences in manual imitation fidelity

    Science.gov (United States)

    Braadbaart, Lieke; Waiter, Gordon D.; Williams, Justin H. G.

    2012-01-01

    Imitation is crucial for social learning, and so it is important to identify what determines between-subject variability in imitation fidelity. This might help explain what makes some people, like those with social difficulties such as in autism spectrum disorder (ASD), significantly worse at performance on these tasks than others. A novel paradigm was developed to provide objective measures of imitation fidelity in which participants used a touchscreen to imitate videos of a model drawing different shapes. Comparisons between model and participants' kinematic data provided three measures of imitative fidelity. We hypothesized that imitative ability would predict variation in BOLD signal whilst performing a simple imitation task in the MRI-scanner. In particular, an overall measure of accuracy (correlation between model and imitator) would predict activity in the overarching imitation system, whereas bias would be subject to more general aspects of motor control. Participants lying in the MRI-scanner were instructed to imitate different grips on a handle, or to watch someone or a circle moving the handle. Our hypothesis was partly confirmed as correlation between model and imitator was mediated by somatosensory cortex but also ventromedial prefrontal cortex, and bias was mediated mainly by cerebellum but also by the medial frontal and parietal cortices and insula. We suggest that this variance differentially reflects cognitive functions such as feedback-sensitivity and reward-dependent learning, contributing significantly to variability in individuals' imitative abilities as characterized by objective kinematic measures. PMID:23087625

  1. Individual differences in satisfaction with activity-based work environments

    NARCIS (Netherlands)

    Hoendervanger, Jan; Ernst, Anja F.; Albers, Casper; Mobach, Mark; Van Yperen, Nico W.

    2018-01-01

    Satisfaction with activity-based work environments (ABW environments) often falls short of expectations, with striking differences among individual workers. A better understanding of these differences may provide clues for optimising satisfaction with ABW environments and associated organisational

  2. Individual Differences in Impulsive Choice and Timing in Rats

    Science.gov (United States)

    Galtress, Tiffany; Garcia, Ana; Kirkpatrick, Kimberly

    2012-01-01

    Individual differences in impulsive choice behavior have been linked to a variety of behavioral problems including substance abuse, smoking, gambling, and poor financial decision-making. Given the potential importance of individual differences in impulsive choice as a predictor of behavioral problems, the present study sought to measure the extent…

  3. Individual differences in perception and response to experimental ...

    African Journals Online (AJOL)

    Background: Pain is a protective sensation that alerts an individual to injury from the environment. Experience of pain is characterised by robust individual differences and complex environmental ... Data were presented as mean ± SD. Differences and statistical significance between the means were determined using t test.

  4. Individual Differences in Consumer Buying Patterns: A Behavioral Economic Analysis

    Science.gov (United States)

    Cavalcanti, Paulo R.; Oliveira-Castro, Jorge M.; Foxall, Gordon R.

    2013-01-01

    Although previous studies have identified several regularities in buying behavior, no integrated view of individual differences related to such patterns has been yet proposed. The present research examined individual differences in patterns of buying behavior of fast-moving consumer goods, using panel data with information concerning purchases of…

  5. A neuroimaging investigation of attribute framing and individual differences

    Science.gov (United States)

    Murch, Kevin B.

    2014-01-01

    Functional magnetic resonance imaging was used to evaluate the neural basis of framing effects. We tested the reflexive and reflective systems model of social cognition as it relates to framing. We also examined the relationships among frame susceptibility, intelligence and personality measures. Participants evaluated whether personal attributes applied to themselves from multiple perspectives and in positive and negative frames. Participants rated whether each statement was descriptive or not and endorsed positive frames more than negative frames. Individual differences on frame decisions enabled us to form high and low frame susceptibility groups. Endorsement of frame-consistent attributes was associated with personality factors, cognitive reflection and intelligence. Reflexive brain regions were associated with positive frames while reflective areas were associated with negative frames. Region of Interest analyses showed that frame-inconsistent responses were associated with increased activation within reflective cognitive control regions including the left dorsolateral prefrontal cortex (PFC), dorsomedial PFC and left ventrolateral PFC. Frame-consistent responses were associated with increased activation in the right orbitofrontal cortex. These results demonstrate that individual differences in frame susceptibility influence personal attribute evaluations. Overall, this study clarifies the neural correlates of the reflective and reflexive systems of social cognition as applied to decisions about social attributions. PMID:23988759

  6. Individual differences in children's working memory and writing skill.

    Science.gov (United States)

    Swanson, H L; Berninger, V W

    1996-11-01

    The purpose of this research is to address (a) whether individual differences in working memory (WM) and writing are related to a general or process-specific system, (b) whether WM tasks operate independently of phonological short-term memory (STM) on measures of writing and reading, and (c) whether working memory predicts variance in writing beyond that predicted by reading alone. The present study correlated several WM and phonological STM measures with writing and reading measures. The study showed among the memory measures that a four-factor model reflecting phonological STM, verbal WM span, executive processing, and visual-spatial WM span best fit the multivariate data set. Working memory was correlated significantly with a number of writing measures, particularly those related to text generation. WM measures contributed unique variance to writing that was independent of reading skill, and STM measures best predicted transcription processes and reading recognition, whereas WM measures best predicted text generation and reading comprehension. Both verbal and visual-spatial working memory measures predicted reading comprehension, whereas only WM measures that reflect executive processing significantly predicted writing. In general, the results suggest that individual differences in children's writing reflect a specific capacity system, whereas reading comprehension draws upon a multiple capacity system.

  7. A neuroimaging investigation of attribute framing and individual differences.

    Science.gov (United States)

    Murch, Kevin B; Krawczyk, Daniel C

    2014-10-01

    Functional magnetic resonance imaging was used to evaluate the neural basis of framing effects. We tested the reflexive and reflective systems model of social cognition as it relates to framing. We also examined the relationships among frame susceptibility, intelligence and personality measures. Participants evaluated whether personal attributes applied to themselves from multiple perspectives and in positive and negative frames. Participants rated whether each statement was descriptive or not and endorsed positive frames more than negative frames. Individual differences on frame decisions enabled us to form high and low frame susceptibility groups. Endorsement of frame-consistent attributes was associated with personality factors, cognitive reflection and intelligence. Reflexive brain regions were associated with positive frames while reflective areas were associated with negative frames. Region of Interest analyses showed that frame-inconsistent responses were associated with increased activation within reflective cognitive control regions including the left dorsolateral prefrontal cortex (PFC), dorsomedial PFC and left ventrolateral PFC. Frame-consistent responses were associated with increased activation in the right orbitofrontal cortex. These results demonstrate that individual differences in frame susceptibility influence personal attribute evaluations. Overall, this study clarifies the neural correlates of the reflective and reflexive systems of social cognition as applied to decisions about social attributions. © The Author (2013). Published by Oxford University Press. For Permissions, please email: journals.permissions@oup.com.

  8. Hue opponency: chromatic valence functions, individual differences, cortical winner-take-all opponent modeling, and the relationship between spikes and sensitivity.

    Science.gov (United States)

    Billock, Vincent A

    2018-04-01

    Neural spike rate data are more restricted in range than related psychophysical data. For example, several studies suggest a compressive (roughly cube root) nonlinear relationship between wavelength-opponent spike rates in primate midbrain and color appearance in humans, two rather widely separated domains. This presents an opportunity to partially bridge a chasm between these two domains and to probe the putative nonlinearity with other psychophysical data. Here neural wavelength-opponent data are used to create cortical competition models for hue opponency. This effort led to creation of useful models of spiking neuron winner-take-all (WTA) competition and MAX selection. When fed with actual primate data, the spiking WTA models generate reasonable wavelength-opponent spike rate behaviors. An average psychophysical observer for red-green and blue-yellow opponency is curated from eight applicable studies in the refereed and dissertation literatures, with cancellation data roughly every 10 nm in 18 subjects for yellow-blue opponency and 15 subjects for red-green opponency. A direct mapping between spiking neurons with broadband wavelength sensitivity and human psychophysical luminance yields a power law exponent of 0.27, similar to the cube root nonlinearity. Similarly, direct mapping between the WTA model opponent spike rates and psychophysical opponent data suggests power law relationships with exponents between 0.24 and 0.41.

  9. A cortical edge-integration model of object-based lightness computation that explains effects of spatial context and individual differences

    Science.gov (United States)

    Rudd, Michael E.

    2014-01-01

    Previous work has demonstrated that perceived surface reflectance (lightness) can be modeled in simple contexts in a quantitatively exact way by assuming that the visual system first extracts information about local, directed steps in log luminance, then spatially integrates these steps along paths through the image to compute lightness (Rudd and Zemach, 2004, 2005, 2007). This method of computing lightness is called edge integration. Recent evidence (Rudd, 2013) suggests that human vision employs a default strategy to integrate luminance steps only along paths from a common background region to the targets whose lightness is computed. This implies a role for gestalt grouping in edge-based lightness computation. Rudd (2010) further showed the perceptual weights applied to edges in lightness computation can be influenced by the observer's interpretation of luminance steps as resulting from either spatial variation in surface reflectance or illumination. This implies a role for top-down factors in any edge-based model of lightness (Rudd and Zemach, 2005). Here, I show how the separate influences of grouping and attention on lightness can be modeled in tandem by a cortical mechanism that first employs top-down signals to spatially select regions of interest for lightness computation. An object-based network computation, involving neurons that code for border-ownership, then automatically sets the neural gains applied to edge signals surviving the earlier spatial selection stage. Only the borders that survive both processing stages are spatially integrated to compute lightness. The model assumptions are consistent with those of the cortical lightness model presented earlier by Rudd (2010, 2013), and with neurophysiological data indicating extraction of local edge information in V1, network computations to establish figure-ground relations and border ownership in V2, and edge integration to encode lightness and darkness signals in V4. PMID:25202253

  10. A Cortical Edge-integration Model of Object-Based Lightness Computation that Explains Effects of Spatial Context and Individual Differences

    Directory of Open Access Journals (Sweden)

    Michael E Rudd

    2014-08-01

    Full Text Available Previous work demonstrated that perceived surface reflectance (lightness can be modeled in simple contexts in a quantitatively exact way by assuming that the visual system first extracts information about local, directed steps in log luminance, then spatial integrates these steps along paths through the image to compute lightness (Rudd & Zemach, 2004, 2005, 2007. This method of computing lightness is called edge integration. Recent evidence (Rudd, 2013 suggests that the human vision employs a default strategy to integrate luminance steps only along paths from a common background region to the targets whose lightness is computed. This implies a role for gestalt grouping in edge-based lightness computation. Rudd (2010 further showed the perceptual weights applied to edges in lightness computation can be influenced by the observer’s interpretation of luminance steps as resulting from either spatial variation in surface reflectance or illumination. This implies a role for top-down factors in any edge-based model of lightness (Rudd & Zemach, 2005. Here, I show how the separate influences of grouping and attention on lightness can be together modeled by a cortical mechanism that first employs top-down signals to spatially select regions of interest for lightness computation. An object-based network computation, involving neurons that code for border-ownership, then automatically sets the neural gains applied to edge signals surviving the earlier spatial selection stage. Only the borders that survive both processing stages are spatially integrated to compute lightness. The model assumptions are consistent with those of the cortical lightness model presented earlier by Rudd (2010, 2013, and with neurophysiological data indicating extraction of local edge information in V1, network computations to establish figure-ground relations and border ownership in V2, and edge integration to encode lightness and darkness signals in V4.

  11. A cortical edge-integration model of object-based lightness computation that explains effects of spatial context and individual differences.

    Science.gov (United States)

    Rudd, Michael E

    2014-01-01

    Previous work has demonstrated that perceived surface reflectance (lightness) can be modeled in simple contexts in a quantitatively exact way by assuming that the visual system first extracts information about local, directed steps in log luminance, then spatially integrates these steps along paths through the image to compute lightness (Rudd and Zemach, 2004, 2005, 2007). This method of computing lightness is called edge integration. Recent evidence (Rudd, 2013) suggests that human vision employs a default strategy to integrate luminance steps only along paths from a common background region to the targets whose lightness is computed. This implies a role for gestalt grouping in edge-based lightness computation. Rudd (2010) further showed the perceptual weights applied to edges in lightness computation can be influenced by the observer's interpretation of luminance steps as resulting from either spatial variation in surface reflectance or illumination. This implies a role for top-down factors in any edge-based model of lightness (Rudd and Zemach, 2005). Here, I show how the separate influences of grouping and attention on lightness can be modeled in tandem by a cortical mechanism that first employs top-down signals to spatially select regions of interest for lightness computation. An object-based network computation, involving neurons that code for border-ownership, then automatically sets the neural gains applied to edge signals surviving the earlier spatial selection stage. Only the borders that survive both processing stages are spatially integrated to compute lightness. The model assumptions are consistent with those of the cortical lightness model presented earlier by Rudd (2010, 2013), and with neurophysiological data indicating extraction of local edge information in V1, network computations to establish figure-ground relations and border ownership in V2, and edge integration to encode lightness and darkness signals in V4.

  12. Affect Intensity: An Individual Difference Response to Advertising Appeals.

    OpenAIRE

    Moore, David J; Harris, William D; Chen, Hong C

    1995-01-01

    The Affect Intensity Measurement (AIM) scale assesses the strength of the emotions with which individuals respond to an affect-laden stimulus. This study investigated the extent to which individual differences in affect intensity influence the message recipient's responses to emotional advertising appeals. In two experiments high affect intensity individuals, compared with those who scored low on the AIM scale, (1) manifested significantly stronger emotional responses to the emotional adverti...

  13. Sampling capacity underlies individual differences in human associative learning.

    Science.gov (United States)

    Byrom, Nicola C; Murphy, Robin A

    2014-04-01

    Though much work has studied how external factors, such as stimulus properties, influence generalization of associative strength, there has been limited exploration of the influence that internal dispositions may contribute to stimulus processing. Here we report 2 studies using a modified negative patterning discrimination to test the relationship between global processing and generalization. Global processing was associated with stronger negative patterning discrimination, indicative of limited generalization between distinct stimulus compounds and their constituent elements. In Experiment 2, participants pretrained to adopt global processing similarly showed strong negative patterning discrimination. These results demonstrate considerable individual difference in capacity to engage in negative patterning discrimination and suggest that the tendency toward global processing may be one factor explaining this variability. The need for models of learning to account for this variability in learning is discussed.

  14. Individual differences in cocaine addiction: maladaptive behavioural traits

    NARCIS (Netherlands)

    Homberg, J.R.; Karel, P.G.A.; Verheij, M.M.M.

    2014-01-01

    Cocaine use leads to addiction in only a subset of individuals. Understanding the mechanisms underlying these individual differences in the transition from cocaine use to cocaine abuse is important to develop treatment strategies. There is agreement that specific behavioural traits increase the risk

  15. Individual Differences: Factors Affecting Employee Utilization of Flexible Work Arrangements

    Science.gov (United States)

    Lambert, Alysa D.; Marler, Janet H.; Gueutal, Hal G.

    2008-01-01

    This study investigated individual and organizational factors that predict an individual's choice to use flexible work arrangements (FWAs). Survey data was collected from 144 employees in two different organizations. The results revealed several significant predictors of FWAs: tenure, hours worked per week, supervisory responsibilities,…

  16. Individual differences in the development of scientific thinking in kindergarten

    NARCIS (Netherlands)

    Graaf, J. van der; Segers, P.C.J.; Verhoeven, L.T.W.

    2018-01-01

    The present study examined the development of and individual variation in scientific thinking in kindergarten. We measured experimentation, evidence evaluation, and domain knowledge at two times in kindergarten (T1 and T2) in a sample of 100 five to six-year-olds. To explain individual differences,

  17. Individual model evaluation and probabilistic weighting of models

    International Nuclear Information System (INIS)

    Atwood, C.L.

    1994-01-01

    This note stresses the importance of trying to assess the accuracy of each model individually. Putting a Bayesian probability distribution on a population of models faces conceptual and practical complications, and apparently can come only after the work of evaluating the individual models. Moreover, the primary issue is open-quotes How good is this modelclose quotes? Therefore, the individual evaluations are first in both chronology and importance. They are not easy, but some ideas are given here on how to perform them

  18. Individual differences in the learning potential of human beings

    Science.gov (United States)

    Stern, Elsbeth

    2017-01-01

    To the best of our knowledge, the genetic foundations that guide human brain development have not changed fundamentally during the past 50,000 years. However, because of their cognitive potential, humans have changed the world tremendously in the past centuries. They have invented technical devices, institutions that regulate cooperation and competition, and symbol systems, such as script and mathematics, that serve as reasoning tools. The exceptional learning ability of humans allows newborns to adapt to the world they are born into; however, there are tremendous individual differences in learning ability among humans that become obvious in school at the latest. Cognitive psychology has developed models of memory and information processing that attempt to explain how humans learn (general perspective), while the variation among individuals (differential perspective) has been the focus of psychometric intelligence research. Although both lines of research have been proceeding independently, they increasingly converge, as both investigate the concepts of working memory and knowledge construction. This review begins with presenting state-of-the-art research on human information processing and its potential in academic learning. Then, a brief overview of the history of psychometric intelligence research is combined with presenting recent work on the role of intelligence in modern societies and on the nature-nurture debate. Finally, promising approaches to integrating the general and differential perspective will be discussed in the conclusion of this review.

  19. Individual differences and reasoning: a study on personality traits.

    Science.gov (United States)

    Bensi, Luca; Giusberti, Fiorella; Nori, Raffaella; Gambetti, Elisa

    2010-08-01

    Personality can play a crucial role in how people reason and decide. Identifying individual differences related to how we actively gather information and use evidence could lead to a better comprehension and predictability of human reasoning. Recent findings have shown that some personality traits are related to similar decision-making patterns showed by people with mental disorders. We performed research with the aim to investigate delusion-proneness, obsessive-like personality, anxiety (trait and state), and reasoning styles in individuals from the general population. We introduced personality trait and state anxiety scores in a regression model to explore specific associations with: (1) amount of data-gathered prior to making a decision; and (2) the use of confirmatory and disconfirmatory evidence. Results showed that all our independent variables were positively or negatively associated with the amount of data collected in order to make simple probabilistic decisions. Anxiety and obsessiveness were the only predictors of the weight attributed to evidence in favour or against a hypothesis. Findings were discussed in relation to theoretical assumptions, predictions, and clinical implications. Personality traits can predict peculiar ways to reason and decide that, in turn, could be involved to some extent in the formation and/or maintenance of psychological disorders.

  20. Individual personality differences in Port Jackson sharks Heterodontus portusjacksoni.

    Science.gov (United States)

    Byrnes, E E; Brown, C

    2016-08-01

    This study examined interindividual personality differences between Port Jackson sharks Heterodontus portusjacksoni utilizing a standard boldness assay. Additionally, the correlation between differences in individual boldness and stress reactivity was examined, exploring indications of individual coping styles. Heterodontus portusjacksoni demonstrated highly repeatable individual differences in boldness and stress reactivity. Individual boldness scores were highly repeatable across four trials such that individuals that were the fastest to emerge in the first trial were also the fastest to emerge in subsequent trials. Additionally, individuals that were the most reactive to a handling stressor in the first trial were also the most reactive in a second trial. The strong link between boldness and stress response commonly found in teleosts was also evident in this study, providing evidence of proactive-reactive coping styles in H. portusjacksoni. These results demonstrate the presence of individual personality differences in sharks for the first time. Understanding how personality influences variation in elasmobranch behaviour such as prey choice, habitat use and activity levels is critical to better managing these top predators which play important ecological roles in marine ecosystems. © 2016 The Fisheries Society of the British Isles.

  1. Using principal component analysis to capture individual differences within a unified neuropsychological model of chronic post-stroke aphasia: Revealing the unique neural correlates of speech fluency, phonology and semantics.

    Science.gov (United States)

    Halai, Ajay D; Woollams, Anna M; Lambon Ralph, Matthew A

    2017-01-01

    Individual differences in the performance profiles of neuropsychologically-impaired patients are pervasive yet there is still no resolution on the best way to model and account for the variation in their behavioural impairments and the associated neural correlates. To date, researchers have generally taken one of three different approaches: a single-case study methodology in which each case is considered separately; a case-series design in which all individual patients from a small coherent group are examined and directly compared; or, group studies, in which a sample of cases are investigated as one group with the assumption that they are drawn from a homogenous category and that performance differences are of no interest. In recent research, we have developed a complementary alternative through the use of principal component analysis (PCA) of individual data from large patient cohorts. This data-driven approach not only generates a single unified model for the group as a whole (expressed in terms of the emergent principal components) but is also able to capture the individual differences between patients (in terms of their relative positions along the principal behavioural axes). We demonstrate the use of this approach by considering speech fluency, phonology and semantics in aphasia diagnosis and classification, as well as their unique neural correlates. PCA of the behavioural data from 31 patients with chronic post-stroke aphasia resulted in four statistically-independent behavioural components reflecting phonological, semantic, executive-cognitive and fluency abilities. Even after accounting for lesion volume, entering the four behavioural components simultaneously into a voxel-based correlational methodology (VBCM) analysis revealed that speech fluency (speech quanta) was uniquely correlated with left motor cortex and underlying white matter (including the anterior section of the arcuate fasciculus and the frontal aslant tract), phonological skills with

  2. The 'whys' and 'whens' of individual differences in thinking biases.

    Science.gov (United States)

    De Neys, Wim; Bonnefon, Jean-François

    2013-04-01

    Although human thinking is often biased, some individuals are less susceptible to biases than others. These individual differences have been at the forefront of thinking research for more than a decade. We organize the literature in three key accounts (storage, monitoring, and inhibition failure) and propose that a critical but overlooked question concerns the time point at which individual variance arises: do biased and unbiased reasoners take different paths early on in the reasoning process or is the observed variance late to arise? We discuss how this focus on the 'whens' suggests that individual differences in thinking biases are less profound than traditionally assumed, in the sense that they might typically arise at a later stage of the reasoning process. Copyright © 2013 Elsevier Ltd. All rights reserved.

  3. Real-time individualization of the unified model of performance.

    Science.gov (United States)

    Liu, Jianbo; Ramakrishnan, Sridhar; Laxminarayan, Srinivas; Balkin, Thomas J; Reifman, Jaques

    2017-12-01

    Existing mathematical models for predicting neurobehavioural performance are not suited for mobile computing platforms because they cannot adapt model parameters automatically in real time to reflect individual differences in the effects of sleep loss. We used an extended Kalman filter to develop a computationally efficient algorithm that continually adapts the parameters of the recently developed Unified Model of Performance (UMP) to an individual. The algorithm accomplishes this in real time as new performance data for the individual become available. We assessed the algorithm's performance by simulating real-time model individualization for 18 subjects subjected to 64 h of total sleep deprivation (TSD) and 7 days of chronic sleep restriction (CSR) with 3 h of time in bed per night, using psychomotor vigilance task (PVT) data collected every 2 h during wakefulness. This UMP individualization process produced parameter estimates that progressively approached the solution produced by a post-hoc fitting of model parameters using all data. The minimum number of PVT measurements needed to individualize the model parameters depended upon the type of sleep-loss challenge, with ~30 required for TSD and ~70 for CSR. However, model individualization depended upon the overall duration of data collection, yielding increasingly accurate model parameters with greater number of days. Interestingly, reducing the PVT sampling frequency by a factor of two did not notably hamper model individualization. The proposed algorithm facilitates real-time learning of an individual's trait-like responses to sleep loss and enables the development of individualized performance prediction models for use in a mobile computing platform. © 2017 European Sleep Research Society.

  4. Visualizing Individual Tree Differences in Tree-Ring Studies

    Directory of Open Access Journals (Sweden)

    Mario Trouillier

    2018-04-01

    Full Text Available Averaging tree-ring measurements from multiple individuals is one of the most common procedures in dendrochronology. It serves to filter out noise from individual differences between trees, such as competition, height, and micro-site effects, which ideally results in a site chronology sensitive to regional scale factors such as climate. However, the climate sensitivity of individual trees can be modulated by factors like competition, height, and nitrogen deposition, calling attention to whether average chronologies adequately assess climatic growth-control. In this study, we demonstrate four simple but effective methods to visually assess differences between individual trees. Using individual tree climate-correlations we: (1 employed jitter plots with superimposed metadata to assess potential causes for these differences; (2 plotted the frequency distributions of climate correlations over time as heat maps; (3 mapped the spatial distribution of climate sensitivity over time to assess spatio-temporal dynamics; and (4 used t-distributed Stochastic Neighborhood Embedding (t-SNE to assess which trees were generally more similar in terms of their tree-ring pattern and their correlation with climate variables. This suite of exploratory methods can indicate if individuals in tree-ring datasets respond differently to climate variability, and therefore, should not solely be explored with climate correlations of the mean population chronology.

  5. ASSESSING INDIVIDUAL PERFORMANCE ON INFORMATION TECHNOLOGY ADOPTION: A NEW MODEL

    OpenAIRE

    Diah Hari Suryaningrum

    2012-01-01

    This paper aims to propose a new model in assessing individual performance on information technology adoption. The new model to assess individual performance was derived from two different theories: decomposed theory of planned behavior and task-technology fit theory. Although many researchers have tried to expand these theories, some of their efforts might lack of theoretical assumptions. To overcome this problem and enhance the coherence of the integration, I used a theory from social scien...

  6. INDIVIDUAL BASED MODELLING APPROACH TO THERMAL ...

    Science.gov (United States)

    Diadromous fish populations in the Pacific Northwest face challenges along their migratory routes from declining habitat quality, harvest, and barriers to longitudinal connectivity. Changes in river temperature regimes are producing an additional challenge for upstream migrating adult salmon and steelhead, species that are sensitive to absolute and cumulative thermal exposure. Adult salmon populations have been shown to utilize cold water patches along migration routes when mainstem river temperatures exceed thermal optimums. We are employing an individual based model (IBM) to explore the costs and benefits of spatially-distributed cold water refugia for adult migrating salmon. Our model, developed in the HexSim platform, is built around a mechanistic behavioral decision tree that drives individual interactions with their spatially explicit simulated environment. Population-scale responses to dynamic thermal regimes, coupled with other stressors such as disease and harvest, become emergent properties of the spatial IBM. Other model outputs include arrival times, species-specific survival rates, body energetic content, and reproductive fitness levels. Here, we discuss the challenges associated with parameterizing an individual based model of salmon and steelhead in a section of the Columbia River. Many rivers and streams in the Pacific Northwest are currently listed as impaired under the Clean Water Act as a result of high summer water temperatures. Adverse effec

  7. Accounting for taste: individual differences in preference for harmony.

    Science.gov (United States)

    Palmer, Stephen E; Griscom, William S

    2013-06-01

    Although empirical research on aesthetics has had some success in explaining the average preferences of groups of observers, relatively little is known about individual differences in preference, and especially about how such differences might covary across different domains. In this study, we identified a new factor underlying aesthetic response-preference for harmonious stimuli-and examined how it varies over four domains (color, shape, spatial location, and music) across individuals with different levels of training in art and music. We found that individual preferences for harmony are strongly correlated across all four dimensions tested and decrease consistently with training in the relevant aesthetic domains. Confirmatory factor analysis revealed that cross-domain preference for harmony is well-represented as a single, unified factor, with effects separate from those of training and of common personality measures.

  8. Developmental and Individual Differences in Understanding of Fractions

    Science.gov (United States)

    Siegler, Robert S.; Pyke, Aryn A.

    2013-01-01

    We examined developmental and individual differences in 6th and 8th graders' fraction arithmetic and overall mathematics achievement and related them to differences in understanding of fraction magnitudes, whole number division, executive functioning, and metacognitive judgments within a crosssectional design. Results indicated that the difference…

  9. Consistent individual differences in fathering in threespined stickleback Gasterosteus aculeatus

    Directory of Open Access Journals (Sweden)

    Laura R. STEIN, Alison M. BELL

    2012-02-01

    Full Text Available There is growing evidence that individual animals show consistent differences in behavior. For example, individual threespined stickleback fish differ in how they react to predators and how aggressive they are during social interactions with conspecifics. A relatively unexplored but potentially important axis of variation is parental behavior. In sticklebacks, fathers provide all of the parental care that is necessary for offspring survival; therefore paternal care is directly tied to fitness. In this study, we assessed whether individual male sticklebacks differ consistently from each other in parental behavior. We recorded visits to nest, total time fanning, and activity levels of 11 individual males every day throughout one clutch, and then allowed the males to breed again. Half of the males were exposed to predation risk while parenting during the first clutch, and the other half of the males experienced predation risk during the second clutch. We detected dramatic temporal changes in parental behaviors over the course of the clutch: for example, total time fanning increased six-fold prior to eggs hatching, then decreased to approximately zero. Despite these temporal changes, males retained their individually-distinctive parenting styles within a clutch that could not be explained by differences in body size or egg mass. Moreover, individual differences in parenting were maintained when males reproduced for a second time. Males that were exposed to simulated predation risk briefly decreased fanning and increased activity levels. Altogether, these results show that individual sticklebacks consistently differ from each other in how they behave as parents [Current Zoology 58 (1: 45–52, 2012].

  10. Consistent individual differences in fathering in threespined stickleback Gasterosteus aculeatus

    Institute of Scientific and Technical Information of China (English)

    Laura R. STEIN; Alison M. BELL

    2012-01-01

    There is growing evidence that individual animals show consistent differences in behavior.For example,individual threespined stickleback fish differ in how they react to predators and how aggressive they are during social interactions with conspecifics.A relatively unexplored but potentially important axis of variation is parental behavior.In sticklebacks,fathers provide all of the parental care that is necessary for offspring survival; therefore paternal care is directly tied to fimess.In this study,we assessed whether individual male sticklebacks differ consistently from each other in parental behavior.We recorded visits to nest,total time fanning,and activity levels of 11 individual males every day throughout one clutch,and then allowed the males to breed again.Half of the males were exposed to predation risk while parenting during the fast clutch,and the other half of the males experienced predation risk during the second clutch.We detected dramatic temporal changes in parental behaviors over the course of the clutch:for example,total time fanning increased six-fold prior to eggs hatching,then decreased to approximately zero.Despite these temporal changes,males retained their individually-distinctive parenting styles within a clutch that could not be explained by differences in body size or egg mass.Moreover,individual differences in parenting were maintained when males reproduced for a second time.Males that were exposed to simulated predation risk briefly decreased fanning and increased activity levels.Altogether,these results show that individual sticklebacks consistently differ from each other in how they behave as parents [Current Zoology 58 (1):45-52,2012].

  11. Ecological influences on individual differences in color preference.

    Science.gov (United States)

    Schloss, Karen B; Hawthorne-Madell, Daniel; Palmer, Stephen E

    2015-11-01

    How can the large, systematic differences that exist between individuals' color preferences be explained? The ecological valence theory (Palmer & Schloss, Proceedings of the National Academy of Sciences 107:8877-8882, 2010) posits that an individual's preference for each particular color is determined largely by his or her preferences for all correspondingly colored objects. Therefore, individuals should differ in their color preferences to the extent that they have different preferences for the same color-associated objects or that they experience different objects. Supporting this prediction, we found that individuals' color preferences were predicted better by their own preferences for correspondingly colored objects than by other peoples' preferences for the same objects. Moreover, the fit between color preferences and affect toward the colored objects was reliably improved when people's own idiosyncratic color-object associations were included in addition to a standard set of color-object associations. These and related results provide evidence that individual differences in color preferences are reliably influenced by people's personal experiences with colored objects in their environment.

  12. Individualized Biomathematical Modeling of Fatigue and Performance

    Science.gov (United States)

    2008-05-29

    Interactions and Transitions 53 New Discoveries , Inventions, or Patent Disclosures 56 FA9550-06-1-0055 Individualized Biomathematical Modeling of Fatigue...Old Dominion University, not supported on grant) Daniel J. Mollicone, Ph.D. ( Pulsar Informatics, Inc., not supported on grant) Christopher G...Mott, M.S. ( Pulsar Informatics, Inc., not supported on grant) Erik Olofsen, M.S. (Leiden University, the Netherlands, not supported on grant

  13. Regional differences of the urinary proteomes in healthy Chinese individuals

    OpenAIRE

    Qin, Weiwei; Wu, Jianqiang; Pan, Li; Zhang, Fanshuang; Wang, Xiaorong; Zhang, Biao; Shan, Guangliang; Gao, Youhe

    2017-01-01

    Urine is a promising biomarker source for clinical proteomics studies. Although regional physiological differences are common in multi-center clinical studies, the presence of significant differences in the urinary proteomes of individuals from different regions remains unknown. In this study, morning urine samples were collected from healthy urban residents in three regions of China and urinary proteins were preserved using a membrane-based method (Urimem). The urine proteomes of 27 normal s...

  14. Individual differences in working memory capacity predict visual attention allocation.

    Science.gov (United States)

    Bleckley, M Kathryn; Durso, Francis T; Crutchfield, Jerry M; Engle, Randall W; Khanna, Maya M

    2003-12-01

    To the extent that individual differences in working memory capacity (WMC) reflect differences in attention (Baddeley, 1993; Engle, Kane, & Tuholski, 1999), differences in WMC should predict performance on visual attention tasks. Individuals who scored in the upper and lower quartiles on the OSPAN working memory test performed a modification of Egly and Homa's (1984) selective attention task. In this task, the participants identified a central letter and localized a displaced letter flashed somewhere on one of three concentric rings. When the displaced letter occurred closer to fixation than the cue implied, high-WMC, but not low-WMC, individuals showed a cost in the letter localization task. This suggests that low-WMC participants allocated attention as a spotlight, whereas those with high WMC showed flexible allocation.

  15. Individual Differences in Components of Reaction Time Distributions and Their Relations to Working Memory and Intelligence

    Science.gov (United States)

    Schmiedek, Florian; Oberauer, Klaus; Wilhelm, Oliver; Suss, Heinz-Martin; Wittmann, Werner W.

    2007-01-01

    The authors bring together approaches from cognitive and individual differences psychology to model characteristics of reaction time distributions beyond measures of central tendency. Ex-Gaussian distributions and a diffusion model approach are used to describe individuals' reaction time data. The authors identified common latent factors for each…

  16. Individual differences and subjective workload assessment - Comparing pilots to nonpilots

    Science.gov (United States)

    Vidulich, Michael A.; Pandit, Parimal

    1987-01-01

    Results by two groups of subjects, pilots and nonpilots, for two subjective workload assessment techniques (the SWAT and NASA-TLX tests) intended to evaluate individual differences in the perception and reporting of subjective workload are compared with results obtained for several traditional personality tests. The personality tests were found to discriminate between the groups while the workload tests did not. It is concluded that although the workload tests may provide useful information with respect to the interaction between tasks and personality, they are not effective as pure tests of individual differences.

  17. Individual Differences in Zhong-Yong tendency and Processing Capacity

    Directory of Open Access Journals (Sweden)

    Ting-Yun eChang

    2014-11-01

    Full Text Available The present study investigated how an individual’s Zhong-Yong tendency is related to his/her perceptual processing capacity. In two experiments, participants completed a Zhong-Yong Thinking Style Scale and performed a redundant-target detection task. Processing capacity was assessed with a nonparametric approach (systems factorial technology, SFT and a parametric (linear ballistic accumulator model, LBA approach. Results converged to suggest a positive correlation between Zhong-Yong tendency and processing capacity. High middle-way thinkers had larger processing capacity in multiple-signal processing compared with low middle-way thinkers, indicating that they processed information more efficiently and in an integrated fashion. Zhong-Yong tendency positively correlates with the processing capacity. These findings suggest that the individual differences in processing capacity can account for the reasons why high middle-way thinkers tend to adopt a global and flexible processing strategy to deal with the external world. Furthermore, the influence of culturally dictated thinking style on cognition can be revealed in a perception task.

  18. Examination of Automation-Induced Complacency and Individual Difference Variates

    Science.gov (United States)

    Prinzel, Lawrence J., III; DeVries, Holly; Freeman, Fred G.; Mikulka, Peter

    2001-01-01

    Automation-induced complacency has been documented as a cause or contributing factor in many airplane accidents throughout the last two decades. It is surmised that the condition results when a crew is working in highly reliable automated environments in which they serve as supervisory controllers monitoring system states for occasional automation failures. Although many reports have discussed the dangers of complacency, little empirical research has been produced to substantiate its harmful effects on performance as well as what factors produce complacency. There have been some suggestions, however, that individual characteristics could serve as possible predictors of performance in automated systems. The present study examined relationship between the individual differences of complacency potential, boredom proneness, and cognitive failure, automation-induced complacency. Workload and boredom scores were also collected and analyzed in relation to the three individual differences. The results of the study demonstrated that there are personality individual differences that are related to whether an individual will succumb to automation-induced complacency. Theoretical and practical implications are discussed.

  19. Facility for sustained positive affect as an individual difference characteristic

    Directory of Open Access Journals (Sweden)

    Nicola S. Schutte

    2015-12-01

    Full Text Available A series of studies investigated a proposed new individual difference characteristic or trait, facility for sustained positive affect, consisting of tendencies that allow individuals to maintain a high level of positive mood. Exploratory and confirmatory factor analyses resulted in the creation of a measure, the self-congruent and new activities (SANA scale which identified two core aspects of sustainable positive affect, engaging in self-congruent activities and engaging in new activities. A higher level of facility for sustainable affect, as operationalized by the SANA scale, was associated with maintenance of positive mood for a month, fewer symptoms of depression and anxiety, less negative affect, and more life satisfaction, relationship satisfaction, work satisfaction, mindfulness, personal expansion and growth, and emotional intelligence. The results provided initial evidence that facility to maintain positive affect may be an emotion-related individual difference characteristic.

  20. Individual differences in individualism and collectivism predict ratings of virtual cities' liveability and environmental quality.

    Science.gov (United States)

    Rubin, Mark; Morrison, Tessa

    2014-01-01

    The present research investigated individual differences in individualism and collectivism as predictors of people's reactions to cities. Psychology undergraduate students (N = 148) took virtual guided tours around historical cities. They then evaluated the cities' liveability and environmental quality and completed measures of individualism and collectivism. Mediation analyses showed that people who scored high in self-responsibility (individualism) rated the cities as more liveable because they perceived them to be richer and better resourced. In contrast, people who scored high in collectivism rated the cities as having a better environmental quality because they perceived them to (1) provide a greater potential for community and social life and (2) allow people to express themselves. These results indicate that people's evaluations of virtual cities are based on the degree to which certain aspects of the cities are perceived to be consistent with individualist and collectivist values.

  1. Developmental and Individual Differences in Pure Numerical Estimation

    Science.gov (United States)

    Booth, Julie L.; Siegler, Robert S.

    2006-01-01

    The authors examined developmental and individual differences in pure numerical estimation, the type of estimation that depends solely on knowledge of numbers. Children between kindergarten and 4th grade were asked to solve 4 types of numerical estimation problems: computational, numerosity, measurement, and number line. In Experiment 1,…

  2. Sources of Individual Differences in Children's Understanding of Fractions

    Science.gov (United States)

    Vukovic, Rose K.; Fuchs, Lynn S.; Geary, David C.; Jordan, Nancy C.; Gersten, Russell; Siegler, Robert S.

    2014-01-01

    Longitudinal associations of domain-general and numerical competencies with individual differences in children's understanding of fractions were investigated. Children (n = 163) were assessed at 6 years of age on domain-general (nonverbal reasoning, language, attentive behavior, executive control, visual-spatial memory) and numerical (number…

  3. Individual Differences in Depth and Breadth of Processing.

    Science.gov (United States)

    Schmeck, Ronald R.; McCarthy, Patricia

    Memory has been defined as traces left behind by past information processing. One approach to the study of everyday memory is to isolate reliable differences between individuals in the ways in which they process information when preparing for test events. The Inventory of Learning Processes, consisting of four scales, i.e., Deep Processing,…

  4. Responding to Individual Differences in Inclusive Classrooms in Australia

    Science.gov (United States)

    van Kraayenoord, Christina E.; Waterworth, David; Brady, Trish

    2014-01-01

    Responding to individual differences in classrooms in which there is increasing diversity is one of the challenges of inclusive education in Australia. The linking of Universal Design for Learning (UDL) and assistive technologies (ATs) is one way in which this challenge can be addressed. This article describes an initiative, known as…

  5. Individual Differences on Job Stress and Related Ill Health

    Directory of Open Access Journals (Sweden)

    Miodraga Stefanovska Petkovska

    2014-03-01

    Conclusion: Employees are exposed to many potential work related stressors which differently affect their job satisfaction and result in ill health. A better understanding of the individual characteristics and potential stressors should subsequently help managers' better deal with this problem. This underlines the need for further research and design of stress reduction interventions.

  6. Accounting for individual differences in human associative learning

    OpenAIRE

    Byrom, Nicola C.

    2013-01-01

    Associative learning has provided fundamental insights to understanding psychopathology. However, psychopathology occurs along a continuum and as such, identification of disruptions in processes of associative learning associated with aspects of psychopathology illustrates a general flexibility in human associative learning. A handful of studies have looked specifically at individual differences in human associative learning, but while much work has concentrated on accounting for flexibility ...

  7. Individual differences in memory span: relationship between rate of ...

    African Journals Online (AJOL)

    Individual differences in memory span: relationship between rate of item identification and rate of reading. AM Sunmola, CC Ukachi, JI Osu. Abstract. No Abstract Available African Journal for the Psychological Study of Social Issues Vol.4(1) 1999: 74-78. Full Text: EMAIL FULL TEXT EMAIL FULL TEXT · DOWNLOAD FULL ...

  8. Functional connectivity patterns reflect individual differences in conflict adaptation.

    Science.gov (United States)

    Wang, Xiangpeng; Wang, Ting; Chen, Zhencai; Hitchman, Glenn; Liu, Yijun; Chen, Antao

    2015-04-01

    Individuals differ in the ability to utilize previous conflict information to optimize current conflict resolution, which is termed the conflict adaptation effect. Previous studies have linked individual differences in conflict adaptation to distinct brain regions. However, the network-based neural mechanisms subserving the individual differences of the conflict adaptation effect have not been studied. The present study employed a psychophysiological interaction (PPI) analysis with a color-naming Stroop task to examine this issue. The main results were as follows: (1) the anterior cingulate cortex (ACC)-seeded PPI revealed the involvement of the salience network (SN) in conflict adaptation, while the posterior parietal cortex (PPC)-seeded PPI revealed the engagement of the central executive network (CEN). (2) Participants with high conflict adaptation effect showed higher intra-CEN connectivity and lower intra-SN connectivity; while those with low conflict adaptation effect showed higher intra-SN connectivity and lower intra-CEN connectivity. (3) The PPC-centered intra-CEN connectivity positively predicted the conflict adaptation effect; while the ACC-centered intra-SN connectivity had a negative correlation with this effect. In conclusion, our data demonstrated that conflict adaptation is likely supported by the CEN and the SN, providing a new perspective on studying individual differences in conflict adaptation on the basis of large-scale networks. Copyright © 2015 Elsevier Ltd. All rights reserved.

  9. Assessing Soldier Individual Differences to Enable Tailored Training

    Science.gov (United States)

    2010-04-01

    upon effective and efficient training. However, there is ample evidence that learning-related individual differences exist ( Thorndike , 1985; Jensen...in both civilian and military settings (Schmidt, Hunter, & Outerbridge, 1986; Thorndike , 1985). Prior knowledge or knowledge of facts and...predictive power ( Thorndike , 1985; Jensen, 1998). Further, there is a good deal of evidence that general mental ability impacts performance largely

  10. Developmental and individual differences in pure numerical estimation.

    Science.gov (United States)

    Booth, Julie L; Siegler, Robert S

    2006-01-01

    The authors examined developmental and individual differences in pure numerical estimation, the type of estimation that depends solely on knowledge of numbers. Children between kindergarten and 4th grade were asked to solve 4 types of numerical estimation problems: computational, numerosity, measurement, and number line. In Experiment 1, kindergartners and 1st, 2nd, and 3rd graders were presented problems involving the numbers 0-100; in Experiment 2, 2nd and 4th graders were presented problems involving the numbers 0-1,000. Parallel developmental trends, involving increasing reliance on linear representations of numbers and decreasing reliance on logarithmic ones, emerged across different types of estimation. Consistent individual differences across tasks were also apparent, and all types of estimation skill were positively related to math achievement test scores. Implications for understanding of mathematics learning in general are discussed. Copyright 2006 APA, all rights reserved.

  11. On the motivational properties of reward cues: Individual differences.

    Science.gov (United States)

    Robinson, Terry E; Yager, Lindsay M; Cogan, Elizabeth S; Saunders, Benjamin T

    2014-01-01

    Cues associated with rewards, such as food or drugs of abuse, can themselves acquire motivational properties. Acting as incentive stimuli, such cues can exert powerful control over motivated behavior, and in the case of cues associated with drugs, they can goad continued drug-seeking behavior and relapse. However, recent studies reviewed here suggest that there are large individual differences in the extent to which food and drug cues are attributed with incentive salience. Rats prone to approach reward cues (sign-trackers) attribute greater motivational value to discrete localizable cues and interoceptive cues than do rats less prone to approach reward cues (goal-trackers). In contrast, contextual cues appear to exert greater control over motivated behavior in goal-trackers than sign-trackers. It is possible to predict, therefore, before any experience with drugs, in which animals specific classes of drug cues will most likely reinstate drug-seeking behavior. The finding that different individuals may be sensitive to different triggers capable of motivating behavior and producing relapse suggests there may be different pathways to addiction, and has implications for thinking about individualized treatment. This article is part of a Special Issue entitled 'NIDA 40th Anniversary Issue'. Copyright © 2013 Elsevier Ltd. All rights reserved.

  12. Relationship between individual differences in speech processing and cognitive functions.

    Science.gov (United States)

    Ou, Jinghua; Law, Sam-Po; Fung, Roxana

    2015-12-01

    A growing body of research has suggested that cognitive abilities may play a role in individual differences in speech processing. The present study took advantage of a widespread linguistic phenomenon of sound change to systematically assess the relationships between speech processing and various components of attention and working memory in the auditory and visual modalities among typically developed Cantonese-speaking individuals. The individual variations in speech processing are captured in an ongoing sound change-tone merging in Hong Kong Cantonese, in which typically developed native speakers are reported to lose the distinctions between some tonal contrasts in perception and/or production. Three groups of participants were recruited, with a first group of good perception and production, a second group of good perception but poor production, and a third group of good production but poor perception. Our findings revealed that modality-independent abilities of attentional switching/control and working memory might contribute to individual differences in patterns of speech perception and production as well as discrimination latencies among typically developed speakers. The findings not only have the potential to generalize to speech processing in other languages, but also broaden our understanding of the omnipresent phenomenon of language change in all languages.

  13. Vantage sensitivity: individual differences in response to positive experiences.

    Science.gov (United States)

    Pluess, Michael; Belsky, Jay

    2013-07-01

    The notion that some people are more vulnerable to adversity as a function of inherent risk characteristics is widely embraced in most fields of psychology. This is reflected in the popularity of the diathesis-stress framework, which has received a vast amount of empirical support over the years. Much less effort has been directed toward the investigation of endogenous factors associated with variability in response to positive influences. One reason for the failure to investigate individual differences in response to positive experiences as a function of endogenous factors may be the absence of adequate theoretical frameworks. According to the differential-susceptibility hypothesis, individuals generally vary in their developmental plasticity regardless of whether they are exposed to negative or positive influences--a notion derived from evolutionary reasoning. On the basis of this now well-supported proposition, we advance herein the new concept of vantage sensitivity, reflecting variation in response to exclusively positive experiences as a function of individual endogenous characteristics. After distinguishing vantage sensitivity from theoretically related concepts of differential-susceptibility and resilience, we review some recent empirical evidence for vantage sensitivity featuring behavioral, physiological, and genetic factors as moderators of a wide range of positive experiences ranging from family environment and psychotherapy to educational intervention. Thereafter, we discuss genetic and environmental factors contributing to individual differences in vantage sensitivity, potential mechanisms underlying vantage sensitivity, and practical implications. 2013 APA, all rights reserved

  14. Modeling individual animal histories with multistate capture–recapture models

    Science.gov (United States)

    Lebreton, Jean-Dominique; Nichols, James D.; Barker, Richard J.; Pradel, Roger; Spendelow, Jeffrey A.

    2009-01-01

    Many fields of science begin with a phase of exploration and description, followed by investigations of the processes that account for observed patterns. The science of ecology is no exception, and recent decades have seen a focus on understanding key processes underlying the dynamics of ecological systems. In population ecology, emphasis has shifted from the state variable of population size to the demographic processes responsible for changes in this state variable: birth, death, immigration, and emigration. In evolutionary ecology, some of these same demographic processes, rates of birth and death, are also the determinants of fitness. In animal population ecology, the estimation of state variables and their associated vital rates is especially problematic because of the difficulties in sampling such populations and detecting individual animals. Indeed, early capture–recapture models were developed for the purpose of estimating population size, given the reality that all animals are not caught or detected at any sampling occasion. More recently, capture–recapture models for open populations were developed to draw inferences about survival in the face of these same sampling problems. The focus of this paper is on multi‐state mark–recapture models (MSMR), which first appeared in the 1970s but have undergone substantial development in the last 15 years. These models were developed to deal explicitly with biological variation, in that animals in different “states” (classes defined by location, physiology, behavior, reproductive status, etc.) may have different probabilities of survival and detection. Animal transitions between states are also stochastic and themselves of interest. These general models have proven to be extremely useful and provide a way of thinking about a remarkably wide range of important ecological processes. These methods are now at a stage of refinement and sophistication where they can readily be used by biologists to tackle a wide

  15. Salivary microbiota in individuals with different levels of caries experience

    DEFF Research Database (Denmark)

    Belstrøm, Daniel; Holmstrup, Palle; Fiehn, Nils-Erik

    2017-01-01

    This study compared salivary bacterial profiles in two groups having a 10-fold difference in levels of caries experience, as it was hypothesized that the composition of the salivary microbiota might associate with the levels of caries experience. Bacterial profiles in stimulated saliva samples from...... caries experience. Consequently, longitudinal studies are required to determine if the composition of the salivary microbiota might be a predictive factor of caries risk at the individual level....

  16. Individual differences in adaptive coding of face identity are linked to individual differences in face recognition ability.

    Science.gov (United States)

    Rhodes, Gillian; Jeffery, Linda; Taylor, Libby; Hayward, William G; Ewing, Louise

    2014-06-01

    Despite their similarity as visual patterns, we can discriminate and recognize many thousands of faces. This expertise has been linked to 2 coding mechanisms: holistic integration of information across the face and adaptive coding of face identity using norms tuned by experience. Recently, individual differences in face recognition ability have been discovered and linked to differences in holistic coding. Here we show that they are also linked to individual differences in adaptive coding of face identity, measured using face identity aftereffects. Identity aftereffects correlated significantly with several measures of face-selective recognition ability. They also correlated marginally with own-race face recognition ability, suggesting a role for adaptive coding in the well-known other-race effect. More generally, these results highlight the important functional role of adaptive face-coding mechanisms in face expertise, taking us beyond the traditional focus on holistic coding mechanisms. PsycINFO Database Record (c) 2014 APA, all rights reserved.

  17. Individual differences in the calibration of trust in automation.

    Science.gov (United States)

    Pop, Vlad L; Shrewsbury, Alex; Durso, Francis T

    2015-06-01

    The objective was to determine whether operators with an expectancy that automation is trustworthy are better at calibrating their trust to changes in the capabilities of automation, and if so, why. Studies suggest that individual differences in automation expectancy may be able to account for why changes in the capabilities of automation lead to a substantial change in trust for some, yet only a small change for others. In a baggage screening task, 225 participants searched for weapons in 200 X-ray images of luggage. Participants were assisted by an automated decision aid exhibiting different levels of reliability. Measures of expectancy that automation is trustworthy were used in conjunction with subjective measures of trust and perceived reliability to identify individual differences in trust calibration. Operators with high expectancy that automation is trustworthy were more sensitive to changes (both increases and decreases) in automation reliability. This difference was eliminated by manipulating the causal attribution of automation errors. Attributing the cause of automation errors to factors external to the automation fosters an understanding of tasks and situations in which automation differs in reliability and may lead to more appropriate trust. The development of interventions can lead to calibrated trust in automation. © 2014, Human Factors and Ergonomics Society.

  18. Individual-based modeling of ecological and evolutionary processes

    Science.gov (United States)

    DeAngelis, Donald L.; Mooij, Wolf M.

    2005-01-01

    Individual-based models (IBMs) allow the explicit inclusion of individual variation in greater detail than do classical differential-equation and difference-equation models. Inclusion of such variation is important for continued progress in ecological and evolutionary theory. We provide a conceptual basis for IBMs by describing five major types of individual variation in IBMs: spatial, ontogenetic, phenotypic, cognitive, and genetic. IBMs are now used in almost all subfields of ecology and evolutionary biology. We map those subfields and look more closely at selected key papers on fish recruitment, forest dynamics, sympatric speciation, metapopulation dynamics, maintenance of diversity, and species conservation. Theorists are currently divided on whether IBMs represent only a practical tool for extending classical theory to more complex situations, or whether individual-based theory represents a radically new research program. We feel that the tension between these two poles of thinking can be a source of creativity in ecology and evolutionary theory.

  19. Individual differences in regulatory focus predict neural response to reward.

    Science.gov (United States)

    Scult, Matthew A; Knodt, Annchen R; Hanson, Jamie L; Ryoo, Minyoung; Adcock, R Alison; Hariri, Ahmad R; Strauman, Timothy J

    2017-08-01

    Although goal pursuit is related to both functioning of the brain's reward circuits and psychological factors, the literatures surrounding these concepts have often been separate. Here, we use the psychological construct of regulatory focus to investigate individual differences in neural response to reward. Regulatory focus theory proposes two motivational orientations for personal goal pursuit: (1) promotion, associated with sensitivity to potential gain, and (2) prevention, associated with sensitivity to potential loss. The monetary incentive delay task was used to manipulate reward circuit function, along with instructional framing corresponding to promotion and prevention in a within-subject design. We observed that the more promotion oriented an individual was, the lower their ventral striatum response to gain cues. Follow-up analyses revealed that greater promotion orientation was associated with decreased ventral striatum response even to no-value cues, suggesting that promotion orientation may be associated with relatively hypoactive reward system function. The findings are also likely to represent an interaction between the cognitive and motivational characteristics of the promotion system with the task demands. Prevention orientation did not correlate with ventral striatum response to gain cues, supporting the discriminant validity of regulatory focus theory. The results highlight a dynamic association between individual differences in self-regulation and reward system function.

  20. Influence of demographic and individual difference factors on impulse buying

    Directory of Open Access Journals (Sweden)

    Mirela Mihić

    2010-06-01

    Full Text Available The main purpose of the paper is to determine the correlation of consumers’ demographic or socioeconomic characteristics and individual difference factors on the impulse buying behavior with respect to a number of single impulsivity indicators and one collective indicator. The paper consists of theoretical and research aspects. The first part encompasses theoretical insights into the secondary research regarding impulse buying while the practical part presents the methodology and primary research results. With respect to the subject matter, research goals as well as previous findings and primary research results, corresponding hypotheses were set and mainly confirmed. The results showed that demographic factors, such as the age and working status, are related to most impulse buying indicators and to the impulsivity collective indicator. However, household income produced opposite results. Household income proved to have no major influence on the majority of impulse buying indicators but to be related noticeably to the collective impulsivity indicator, indicating that this result should be regarded with caution. Research results also pointed to the fact that the majority of individual indicators (innovativeness, tendency to the fashionable and shopping enjoyment are positively and negatively related to the impulse buying behavior and that individual difference factors have a greater influence on impulse buying than do demographic characteristics. The paper also summarizes research limitations as well as the work contribution and future research guidelines.

  1. Auditory working memory predicts individual differences in absolute pitch learning.

    Science.gov (United States)

    Van Hedger, Stephen C; Heald, Shannon L M; Koch, Rachelle; Nusbaum, Howard C

    2015-07-01

    Absolute pitch (AP) is typically defined as the ability to label an isolated tone as a musical note in the absence of a reference tone. At first glance the acquisition of AP note categories seems like a perceptual learning task, since individuals must assign a category label to a stimulus based on a single perceptual dimension (pitch) while ignoring other perceptual dimensions (e.g., loudness, octave, instrument). AP, however, is rarely discussed in terms of domain-general perceptual learning mechanisms. This is because AP is typically assumed to depend on a critical period of development, in which early exposure to pitches and musical labels is thought to be necessary for the development of AP precluding the possibility of adult acquisition of AP. Despite this view of AP, several previous studies have found evidence that absolute pitch category learning is, to an extent, trainable in a post-critical period adult population, even if the performance typically achieved by this population is below the performance of a "true" AP possessor. The current studies attempt to understand the individual differences in learning to categorize notes using absolute pitch cues by testing a specific prediction regarding cognitive capacity related to categorization - to what extent does an individual's general auditory working memory capacity (WMC) predict the success of absolute pitch category acquisition. Since WMC has been shown to predict performance on a wide variety of other perceptual and category learning tasks, we predict that individuals with higher WMC should be better at learning absolute pitch note categories than individuals with lower WMC. Across two studies, we demonstrate that auditory WMC predicts the efficacy of learning absolute pitch note categories. These results suggest that a higher general auditory WMC might underlie the formation of absolute pitch categories for post-critical period adults. Implications for understanding the mechanisms that underlie the

  2. Seeing People, Seeing Things: Individual Differences in Selective Attention.

    Science.gov (United States)

    McIntyre, Miranda M; Graziano, William G

    2016-09-01

    Individuals differ in how they deploy attention to their physical and social environments. These differences have been recognized in various forms as orientations, interests, and preferences, but empirical work examining these differences at a cognitive level is scarce. To address this gap, we conducted two studies to explore the links among attentional processes and interests in people and things. The first study measured selective visual attention toward person- and thing-related image content. In the second study, participants were randomly assigned to describe visually presented scenes using either an observational or narrative story format. Linguistic analyses were conducted to assess attentional bias toward interest-congruent content. Outcomes from both studies suggest that attention and motivational processes are linked to differential interests in physical and social environments. © 2016 by the Society for Personality and Social Psychology, Inc.

  3. [Individual differences in behavior and mechanisms of ecological differentiation with fishes as an example].

    Science.gov (United States)

    Budaev, S V; Mikheev, V N; Pavlov, D S

    2015-01-01

    In this paper we present a review of individual differences in animal behavior exemplified by fishes. Main approaches to these differences investigation are outlined. Such terms as temperament can be used to describe consistent characteristics of individuality in animals. It should be emphasized that consistency over time and across situations is the main classification characteristic of the temperament trait. We also briefly review genetic and physiological mechanisms of individuality in fish, factors affecting their development in the ontogeny, and effects of the individual experience. Significant adaptive value of temperament is shown: in many cases the natural selection maintains alternative behavioral tactics. We also consider the main quantitative models accounting for the coexistence of individuals with different behavioral patterns. Finally, it is demonstrated that patterns of behavioral individuality may significantly affect population dynamics.

  4. Autobiographical remembering and individual differences in emotional intelligence.

    Science.gov (United States)

    Yamamoto, Kohsuke; Toyota, Hiroshi

    2013-06-01

    The relationship between individual differences in Emotional Intelligence (EI) and self-reported arousal from remembering an autobiographical emotional or neutral event was examined. Participants (N = 235; 75 men; M age = 18.7 yr., SD = 0.9, range = 18-22) were required to complete the Japanese version of the Emotional Skills and Competence Questionnaire to assess EI. Participants were then asked to recall personal episodes from autobiographical memory, and then completed the Memory Characteristics Questionnaire (MCQ). A group with high EI-rated, emotionally neutral episodes higher than did a group with low EI on several MCQ subscales: sound, participants, overall memory, and doubt/certainty. However, differences in ratings between the two groups were not observed for emotionally positive episodes. These results suggest that high EI is related to more effective use of weak retrieval cues when recalling neutral autobiographical memories.

  5. Inattentional Blindness and Individual Differences in Cognitive Abilities

    Science.gov (United States)

    Kreitz, Carina; Furley, Philip; Memmert, Daniel; Simons, Daniel J.

    2015-01-01

    People sometimes fail to notice salient unexpected objects when their attention is otherwise occupied, a phenomenon known as inattentional blindness. To explore individual differences in inattentional blindness, we employed both static and dynamic tasks that either presented the unexpected object away from the focus of attention (spatial) or near the focus of attention (central). We hypothesized that noticing in central tasks might be driven by the availability of cognitive resources like working memory, and that noticing in spatial tasks might be driven by the limits on spatial attention like attention breadth. However, none of the cognitive measures predicted noticing in the dynamic central task or in either the static or dynamic spatial task. Only in the central static task did working memory capacity predict noticing, and that relationship was fairly weak. Furthermore, whether or not participants noticed an unexpected object in a static task was only weakly associated with their odds of noticing an unexpected object in a dynamic task. Taken together, our results are largely consistent with the notion that noticing unexpected objects is driven more by stochastic processes common to all people than by stable individual differences in cognitive abilities. PMID:26258545

  6. Sustained attention in language production: an individual differences investigation.

    Science.gov (United States)

    Jongman, Suzanne R; Roelofs, Ardi; Meyer, Antje S

    2015-01-01

    Whereas it has long been assumed that most linguistic processes underlying language production happen automatically, accumulating evidence suggests that these processes do require some form of attention. Here we investigated the contribution of sustained attention: the ability to maintain alertness over time. In Experiment 1, participants' sustained attention ability was measured using auditory and visual continuous performance tasks. Subsequently, employing a dual-task procedure, participants described pictures using simple noun phrases and performed an arrow-discrimination task while their vocal and manual response times (RTs) and the durations of their gazes to the pictures were measured. Earlier research has demonstrated that gaze duration reflects language planning processes up to and including phonological encoding. The speakers' sustained attention ability correlated with the magnitude of the tail of the vocal RT distribution, reflecting the proportion of very slow responses, but not with individual differences in gaze duration. This suggests that sustained attention was most important after phonological encoding. Experiment 2 showed that the involvement of sustained attention was significantly stronger in a dual-task situation (picture naming and arrow discrimination) than in simple naming. Thus, individual differences in maintaining attention on the production processes become especially apparent when a simultaneous second task also requires attentional resources.

  7. Inattentional Blindness and Individual Differences in Cognitive Abilities.

    Directory of Open Access Journals (Sweden)

    Carina Kreitz

    Full Text Available People sometimes fail to notice salient unexpected objects when their attention is otherwise occupied, a phenomenon known as inattentional blindness. To explore individual differences in inattentional blindness, we employed both static and dynamic tasks that either presented the unexpected object away from the focus of attention (spatial or near the focus of attention (central. We hypothesized that noticing in central tasks might be driven by the availability of cognitive resources like working memory, and that noticing in spatial tasks might be driven by the limits on spatial attention like attention breadth. However, none of the cognitive measures predicted noticing in the dynamic central task or in either the static or dynamic spatial task. Only in the central static task did working memory capacity predict noticing, and that relationship was fairly weak. Furthermore, whether or not participants noticed an unexpected object in a static task was only weakly associated with their odds of noticing an unexpected object in a dynamic task. Taken together, our results are largely consistent with the notion that noticing unexpected objects is driven more by stochastic processes common to all people than by stable individual differences in cognitive abilities.

  8. Chuck Watson's ``differential psychoacoustics:'' Individual differences in auditory abilities

    Science.gov (United States)

    Kidd, Gary R.

    2004-05-01

    Chuck Watson was among the first in the psychoacoustic community to seriously address the topic of individual differences. At a time when there was little concern with variation among ``normal listeners'' in psychoacoustic research, Watson began a research program to document the range of human auditory abilities. The primary goals were to determine the number of distinct abilities, to specify the nature of each ability, and to document the distribution of these abilities in the general population. Thanks to Watson's talent for organizing and directing large-scale projects and his workmanlike approach to science, a large and valuable body of data on human individual differences has been collected. The research program began about 20 years ago with the study of basic auditory abilities, and it has expanded to include other modalities and cognitive/intellectual abilities in adults and children. A somewhat biased view of the importance of this work will be presented by one of Watson's many colleagues in this endeavor. The talk will provide an overview of this ongoing research program as well as a brief review of some related research by other investigators. New findings from recent extensions of this work will also be discussed.

  9. Inattentional Blindness and Individual Differences in Cognitive Abilities.

    Science.gov (United States)

    Kreitz, Carina; Furley, Philip; Memmert, Daniel; Simons, Daniel J

    2015-01-01

    People sometimes fail to notice salient unexpected objects when their attention is otherwise occupied, a phenomenon known as inattentional blindness. To explore individual differences in inattentional blindness, we employed both static and dynamic tasks that either presented the unexpected object away from the focus of attention (spatial) or near the focus of attention (central). We hypothesized that noticing in central tasks might be driven by the availability of cognitive resources like working memory, and that noticing in spatial tasks might be driven by the limits on spatial attention like attention breadth. However, none of the cognitive measures predicted noticing in the dynamic central task or in either the static or dynamic spatial task. Only in the central static task did working memory capacity predict noticing, and that relationship was fairly weak. Furthermore, whether or not participants noticed an unexpected object in a static task was only weakly associated with their odds of noticing an unexpected object in a dynamic task. Taken together, our results are largely consistent with the notion that noticing unexpected objects is driven more by stochastic processes common to all people than by stable individual differences in cognitive abilities.

  10. Do Sex Differences Define Gender-Related Individual Differences within the Sexes? Evidence from Three Studies.

    Science.gov (United States)

    Lippa, Richard

    1995-01-01

    Studied three different criteria of within-sex, gender-related individual differences taken from three studies. Data showed that items displaying large sex differences tended also to correlate most strongly with independent gender-related criteria within the sexes. Discusses assessment implications for gender-related and other group-related…

  11. Customizing Structure-Function Displacements in the Macula for Individual Differences.

    Science.gov (United States)

    Turpin, Andrew; Chen, Siyuan; Sepulveda, Juan A; McKendrick, Allison M

    2015-09-01

    In the macula, retinal ganglion cells (RGCs) are displaced from their receptive fields. We used optical coherence tomography (OCT) to customize displacements for individual eyes by taking into account macular shape parameters, and determined the likely effect of individual anatomical differences on structure-function mapping in the central visual field. Using the population average model of Drasdo et al. as a starting point, we altered the RGC count in that model based on the ratio of an individual's RGC layer plus inner plexiform layer thickness to the population average on a pointwise basis as a function of eccentricity from the fovea. For 20 adults (age, 24-33; median age, 28) with normal vision, we computed displacements with the original model and our customized approach. We report the variance in displacements among individuals and compare the effects of such displacements on structure-function mapping of the commonly used the 10-2 visual field pattern. As expected, customizing the displacement using individual OCT data made only a small difference on average from the population-based values predicted by the Drasdo et al. model. However, the range between individuals was over 1° at many locations, and closer to 2° at some locations in the superior visual field. Individualizing macular displacement measurements based on OCT data for an individual can result in large spatial shifts in the retinal area corresponding to 10-2 locations, which may be important for clinical structure-function analysis when performed on a local, spatial scale.

  12. Individual differences in first- and second-order temporal judgment.

    Science.gov (United States)

    Corcoran, Andrew W; Groot, Christopher; Bruno, Aurelio; Johnston, Alan; Cropper, Simon J

    2018-01-01

    The ability of subjects to identify and reproduce brief temporal intervals is influenced by many factors whether they be stimulus-based, task-based or subject-based. The current study examines the role individual differences play in subsecond and suprasecond timing judgments, using the schizoptypy personality scale as a test-case approach for quantifying a broad range of individual differences. In two experiments, 129 (Experiment 1) and 141 (Experiment 2) subjects completed the O-LIFE personality questionnaire prior to performing a modified temporal-bisection task. In the bisection task, subjects responded to two identical instantiations of a luminance grating presented in a 4deg window, 4deg above fixation for 1.5 s (Experiment 1) or 3 s (Experiment 2). Subjects initiated presentation with a button-press, and released the button when they considered the stimulus to be half-way through (750/1500 ms). Subjects were then asked to indicate their 'most accurate estimate' of the two intervals. In this way we measure both performance on the task (a first-order measure) and the subjects' knowledge of their performance (a second-order measure). In Experiment 1 the effect of grating-drift and feedback on performance was also examined. Experiment 2 focused on the static/no-feedback condition. For the group data, Experiment 1 showed a significant effect of presentation order in the baseline condition (no feedback), which disappeared when feedback was provided. Moving the stimulus had no effect on perceived duration. Experiment 2 showed no effect of stimulus presentation order. This elimination of the subsecond order-effect was at the expense of accuracy, as the mid-point of the suprasecond interval was generally underestimated. Response precision increased as a proportion of total duration, reducing the variance below that predicted by Weber's law. This result is consistent with a breakdown of the scalar properties of time perception in the early suprasecond range. All

  13. Individual differences in decision making by foraging hummingbirds.

    Science.gov (United States)

    Morgan, Kate V; Hurly, T Andrew; Healy, Susan D

    2014-11-01

    For both humans and animals preference for one option over others can be influenced by the context in which the options occur. In animals, changes in preference could be due to comparative decision-making or to changes in the energy state of the animal when making decisions. We investigated which of these possibilities better explained the response of wild hummingbirds to the addition of a decoy option to a set of two options by presenting Rufous hummingbirds (Selasphorus rufus) with a foraging experiment with two treatments. In each treatment the birds were presented with a binary choice between two options and a trinary choice with three options. In treatment one the binary choice was between a volume option and a concentration option, whereas in treatment two the same volume option was presented alongside an alternative concentration option. In the trinary choice, birds were presented with the same options as in the binary choice plus one of two inferior options. Birds changed their preferences when a poorer option was added to the choice set: birds increased their preference for the same option when in the presence of either decoy. Which option differed across individuals and the changes in preference were not readily explained by either energy maximisation or the decoy effect. The consistency in response within individuals, however, would suggest that the individual itself brings an extra dimension to context-dependent decision-making. This article is part of a Special Issue entitled: Cognition in the wild. Copyright © 2014 Elsevier B.V. All rights reserved.

  14. Primate social attention: Species differences and effects of individual experience in humans, great apes, and macaques.

    Directory of Open Access Journals (Sweden)

    Fumihiro Kano

    Full Text Available When viewing social scenes, humans and nonhuman primates focus on particular features, such as the models' eyes, mouth, and action targets. Previous studies reported that such viewing patterns vary significantly across individuals in humans, and also across closely-related primate species. However, the nature of these individual and species differences remains unclear, particularly among nonhuman primates. In large samples of human and nonhuman primates, we examined species differences and the effects of experience on patterns of gaze toward social movies. Experiment 1 examined the species differences across rhesus macaques, nonhuman apes (bonobos, chimpanzees, and orangutans, and humans while they viewed movies of various animals' species-typical behaviors. We found that each species had distinct viewing patterns of the models' faces, eyes, mouths, and action targets. Experiment 2 tested the effect of individuals' experience on chimpanzee and human viewing patterns. We presented movies depicting natural behaviors of chimpanzees to three groups of chimpanzees (individuals from a zoo, a sanctuary, and a research institute differing in their early social and physical experiences. We also presented the same movies to human adults and children differing in their expertise with chimpanzees (experts vs. novices or movie-viewing generally (adults vs. preschoolers. Individuals varied within each species in their patterns of gaze toward models' faces, eyes, mouths, and action targets depending on their unique individual experiences. We thus found that the viewing patterns for social stimuli are both individual- and species-specific in these closely-related primates. Such individual/species-specificities are likely related to both individual experience and species-typical temperament, suggesting that primate individuals acquire their unique attentional biases through both ontogeny and evolution. Such unique attentional biases may help them learn

  15. Primate social attention: Species differences and effects of individual experience in humans, great apes, and macaques.

    Science.gov (United States)

    Kano, Fumihiro; Shepherd, Stephen V; Hirata, Satoshi; Call, Josep

    2018-01-01

    When viewing social scenes, humans and nonhuman primates focus on particular features, such as the models' eyes, mouth, and action targets. Previous studies reported that such viewing patterns vary significantly across individuals in humans, and also across closely-related primate species. However, the nature of these individual and species differences remains unclear, particularly among nonhuman primates. In large samples of human and nonhuman primates, we examined species differences and the effects of experience on patterns of gaze toward social movies. Experiment 1 examined the species differences across rhesus macaques, nonhuman apes (bonobos, chimpanzees, and orangutans), and humans while they viewed movies of various animals' species-typical behaviors. We found that each species had distinct viewing patterns of the models' faces, eyes, mouths, and action targets. Experiment 2 tested the effect of individuals' experience on chimpanzee and human viewing patterns. We presented movies depicting natural behaviors of chimpanzees to three groups of chimpanzees (individuals from a zoo, a sanctuary, and a research institute) differing in their early social and physical experiences. We also presented the same movies to human adults and children differing in their expertise with chimpanzees (experts vs. novices) or movie-viewing generally (adults vs. preschoolers). Individuals varied within each species in their patterns of gaze toward models' faces, eyes, mouths, and action targets depending on their unique individual experiences. We thus found that the viewing patterns for social stimuli are both individual- and species-specific in these closely-related primates. Such individual/species-specificities are likely related to both individual experience and species-typical temperament, suggesting that primate individuals acquire their unique attentional biases through both ontogeny and evolution. Such unique attentional biases may help them learn efficiently about their

  16. Individual Differences in Gelotophobia Predict Responses to Joy and Contempt

    Directory of Open Access Journals (Sweden)

    Jennifer Hofmann

    2015-04-01

    Full Text Available In a paradigm facilitating smile misattribution, facial responses and ratings to contempt and joy were investigated in individuals with or without gelotophobia (fear of being laughed at. Participants from two independent samples (N1 = 83, N2 = 50 rated the intensity of eight emotions in 16 photos depicting joy, contempt, and different smiles. Facial responses were coded by the Facial Action Coding System in the second study. Compared with non-fearful individuals, gelotophobes rated joy smiles as less joyful and more contemptuous. Moreover, gelotophobes showed less facial joy and more contempt markers. The contempt ratings were comparable between the two groups. Looking at the photos of smiles lifted the positive mood of non-gelotophobes, whereas gelotophobes did not experience an increase. We hypothesize that the interpretation bias of “joyful faces hiding evil minds” (i.e., being also contemptuous and exhibiting less joy facially may complicate social interactions for gelotophobes and serve as a maintaining factor of gelotophobia.

  17. Individual Differences in Recovery Time From Attentional Capture

    Science.gov (United States)

    Fukuda, Keisuke; Vogel, Edward K.

    2015-01-01

    Working memory capacity reflects a core ability of the individual that affects performance on many cognitive tasks. Recent work has suggested that an important covariate of memory capacity is attentional control, and specifically that low-capacity individuals are more susceptible to attentional capture by distractors than high-capacity individuals are, with the latter being able to resist capture. Here, we tested an alternative account according to which all individuals are equally susceptible to attentional capture, but high-capacity individuals recover more quickly than low-capacity individuals. Using psychophysical and electrophysiological methods, we measured recovery time from attentional capture. In two experiments, we found that high- and low-capacity individuals showed equivalent attentional capture effects in the initial moments following capture, but that low-capacity individuals took much longer to recover than high-capacity individuals did. These results suggest that the poor attentional control associated with low capacity is due to slow disengagement from distractors. PMID:21310945

  18. An Individual-based Probabilistic Model for Fish Stock Simulation

    Directory of Open Access Journals (Sweden)

    Federico Buti

    2010-08-01

    Full Text Available We define an individual-based probabilistic model of a sole (Solea solea behaviour. The individual model is given in terms of an Extended Probabilistic Discrete Timed Automaton (EPDTA, a new formalism that is introduced in the paper and that is shown to be interpretable as a Markov decision process. A given EPDTA model can be probabilistically model-checked by giving a suitable translation into syntax accepted by existing model-checkers. In order to simulate the dynamics of a given population of soles in different environmental scenarios, an agent-based simulation environment is defined in which each agent implements the behaviour of the given EPDTA model. By varying the probabilities and the characteristic functions embedded in the EPDTA model it is possible to represent different scenarios and to tune the model itself by comparing the results of the simulations with real data about the sole stock in the North Adriatic sea, available from the recent project SoleMon. The simulator is presented and made available for its adaptation to other species.

  19. Individual differences in false memory from misinformation: cognitive factors.

    Science.gov (United States)

    Zhu, Bi; Chen, Chuansheng; Loftus, Elizabeth F; Lin, Chongde; He, Qinghua; Chen, Chunhui; Li, He; Xue, Gui; Lu, Zhonglin; Dong, Qi

    2010-07-01

    This research investigated the cognitive correlates of false memories that are induced by the misinformation paradigm. A large sample of Chinese college students (N=436) participated in a misinformation procedure and also took a battery of cognitive tests. Results revealed sizable and systematic individual differences in false memory arising from exposure to misinformation. False memories were significantly and negatively correlated with measures of intelligence (measured with Raven's Advanced Progressive Matrices and Wechsler Adult Intelligence Scale), perception (Motor-Free Visual Perception Test, Change Blindness, and Tone Discrimination), memory (Wechsler Memory Scales and 2-back Working Memory tasks), and face judgement (Face Recognition and Facial Expression Recognition). These findings suggest that people with relatively low intelligence and poor perceptual abilities might be more susceptible to the misinformation effect.

  20. Individual differences in emotional complexity: their psychological implications.

    Science.gov (United States)

    Kang, Sun-Mee; Shaver, Phillip R

    2004-08-01

    Two studies explored the nature and psychological implications of individual differences in emotional complexity, defined as having emotional experiences that are broad in range and well differentiated. Emotional complexity was predicted to be associated with private self-consciousness, openness to experience, empathic tendencies, cognitive complexity, ability to differentiate among named emotions, range of emotions experienced daily, and interpersonal adaptability. The Range and Differentiation of Emotional Experience Scale (RDEES) was developed to test these hypotheses. In Study 1 (N=1,129) students completed questionnaire packets containing the RDEES and various outcome measures. Study 2 (N=95) included the RDEES and non-self-report measures such as peer reports, complexity of representations of the emotion domain, and level of ego development measured by a sentence completion test. Results supported all of the hypotheses, providing extensive evidence for the RDEES's construct validity. Findings were discussed in terms of the role of emotional complexity in ego maturity and interpersonal adaptability.

  1. Individual Differences and Rating Errors in First Impressions of Psychopathy

    Directory of Open Access Journals (Sweden)

    Christopher T. A. Gillen

    2016-10-01

    Full Text Available The current study is the first to investigate whether individual differences in personality are related to improved first impression accuracy when appraising psychopathy in female offenders from thin-slices of information. The study also investigated the types of errors laypeople make when forming these judgments. Sixty-seven undergraduates assessed 22 offenders on their level of psychopathy, violence, likability, and attractiveness. Psychopathy rating accuracy improved as rater extroversion-sociability and agreeableness increased and when neuroticism and lifestyle and antisocial characteristics decreased. These results suggest that traits associated with nonverbal rating accuracy or social functioning may be important in threat detection. Raters also made errors consistent with error management theory, suggesting that laypeople overappraise danger when rating psychopathy.

  2. Attachment reorganization following divorce: normative processes and individual differences.

    Science.gov (United States)

    Sbarra, David A; Borelli, Jessica L

    2018-03-21

    This paper uses attachment theory as a lens for reviewing contemporary research on how adults cope with marital separation and loss. The first section of the paper discusses the process of normative attachment reorganization, or the psychology of adaptive grief responses following relationship transitions. We argue that changes two processes, in particular, can be uses to track changes in this normative reorganization process: narrative coherence and self-concept clarity. The second section of the paper suggest that individual differences in attachment anxiety and avoidance shape the variability in this normative reorganization process, largely as a result of the characteristic ways in which these styles organize emotion-regulatory tendencies. The paper closes with a series of integrative questions for future research, including a call for new studies aimed at understanding under what contexts anxiety and avoidance may be adaptive in promoting emotion recovery to separation and divorce experiences. Copyright © 2018 Elsevier Ltd. All rights reserved.

  3. Simulating fiction: individual differences in literature comprehension revealed with FMRI.

    Science.gov (United States)

    Nijhof, Annabel D; Willems, Roel M

    2015-01-01

    When we read literary fiction, we are transported to fictional places, and we feel and think along with the characters. Despite the importance of narrative in adult life and during development, the neurocognitive mechanisms underlying fiction comprehension are unclear. We used functional magnetic resonance imaging (fMRI) to investigate how individuals differently employ neural networks important for understanding others' beliefs and intentions (mentalizing), and for sensori-motor simulation while listening to excerpts from literary novels. Localizer tasks were used to localize both the cortical motor network and the mentalizing network in participants after they listened to excerpts from literary novels. Results show that participants who had high activation in anterior medial prefrontal cortex (aMPFC; part of the mentalizing network) when listening to mentalizing content of literary fiction, had lower motor cortex activity when they listened to action-related content of the story, and vice versa. This qualifies how people differ in their engagement with fiction: some people are mostly drawn into a story by mentalizing about the thoughts and beliefs of others, whereas others engage in literature by simulating more concrete events such as actions. This study provides on-line neural evidence for the existence of qualitatively different styles of moving into literary worlds, and adds to a growing body of literature showing the potential to study narrative comprehension with neuroimaging methods.

  4. Neural correlates of individual differences in manual imitation fidelity

    Directory of Open Access Journals (Sweden)

    Lieke eBraadbaart

    2012-10-01

    Full Text Available Imitation is crucial for social learning, and so it is important to identify what determines between-subject variability in imitation fidelity. This might help explain what makes some people, like those with social difficulties such as in Autism Spectrum Disorder, significantly worse at performance on these tasks than others. A novel paradigm was developed to provide objective measures of imitation fidelity in which participants used a touchscreen to imitate videos of a model drawing different shapes. Comparisons between model and participants’ kinematic data provided three measures of imitative fidelity. We hypothesised that imitative ability would predict variation in BOLD signal whilst performing a simple imitation task in the MRI-scanner. In particular, an overall measure of accuracy (correlation between model and imitator would predict activity in the overarching imitation system, whereas bias would be subject to more general aspects of motor control. Participants lying in the MRI-scanner were instructed to imitate different grips on a handle, or to watch someone or a circle moving the handle. Our hypothesis was partly confirmed as correlation between model and imitator was mediated by somatosensory cortex but also ventromedial prefrontal cortex, and bias was mediated mainly by cerebellum but also by the medial frontal and parietal cortices and insula. We suggest that this variance differentially reflects cognitive functions such as feedback-sensitivity and reward-dependent learning, contributing significantly to variability in individuals’ imitative abilities as characterised by objective kinematic measures.

  5. Individual differences in drivers' cognitive processing of road safety messages.

    Science.gov (United States)

    Kaye, Sherrie-Anne; White, Melanie J; Lewis, Ioni M

    2013-01-01

    Using Gray and McNaughton's (2000) revised reinforcement sensitivity theory (r-RST), we examined the influence of personality on processing of words presented in gain-framed and loss-framed anti-speeding messages and how the processing biases associated with personality influenced message acceptance. The r-RST predicts that the nervous system regulates personality and that behaviour is dependent upon the activation of the behavioural activation system (BAS), activated by reward cues and the fight-flight-freeze system (FFFS), activated by punishment cues. According to r-RST, individuals differ in the sensitivities of their BAS and FFFS (i.e., weak to strong), which in turn leads to stable patterns of behaviour in the presence of rewards and punishments, respectively. It was hypothesised that individual differences in personality (i.e., strength of the BAS and the FFFS) would influence the degree of both message processing (as measured by reaction time to previously viewed message words) and message acceptance (measured three ways by perceived message effectiveness, behavioural intentions, and attitudes). Specifically, it was anticipated that, individuals with a stronger BAS would process the words presented in the gain-frame messages faster than those with a weaker BAS and individuals with a stronger FFFS would process the words presented in the loss-frame messages faster than those with a weaker FFFS. Further, it was expected that greater processing (faster reaction times) would be associated with greater acceptance for that message. Driver licence holding students (N=108) were recruited to view one of four anti-speeding messages (i.e., social gain-frame, social loss-frame, physical gain-frame, and physical loss-frame). A computerised lexical decision task assessed participants' subsequent reaction times to message words, as an indicator of the extent of processing of the previously viewed message. Self-report measures assessed personality and the three message

  6. Consistent Individual Differences Drive Collective Behavior and Group Functioning of Schooling Fish.

    Science.gov (United States)

    Jolles, Jolle W; Boogert, Neeltje J; Sridhar, Vivek H; Couzin, Iain D; Manica, Andrea

    2017-09-25

    The ubiquity of consistent inter-individual differences in behavior ("animal personalities") [1, 2] suggests that they might play a fundamental role in driving the movements and functioning of animal groups [3, 4], including their collective decision-making, foraging performance, and predator avoidance. Despite increasing evidence that highlights their importance [5-16], we still lack a unified mechanistic framework to explain and to predict how consistent inter-individual differences may drive collective behavior. Here we investigate how the structure, leadership, movement dynamics, and foraging performance of groups can emerge from inter-individual differences by high-resolution tracking of known behavioral types in free-swimming stickleback (Gasterosteus aculeatus) shoals. We show that individual's propensity to stay near others, measured by a classic "sociability" assay, was negatively linked to swim speed across a range of contexts, and predicted spatial positioning and leadership within groups as well as differences in structure and movement dynamics between groups. In turn, this trait, together with individual's exploratory tendency, measured by a classic "boldness" assay, explained individual and group foraging performance. These effects of consistent individual differences on group-level states emerged naturally from a generic model of self-organizing groups composed of individuals differing in speed and goal-orientedness. Our study provides experimental and theoretical evidence for a simple mechanism to explain the emergence of collective behavior from consistent individual differences, including variation in the structure, leadership, movement dynamics, and functional capabilities of groups, across social and ecological scales. In addition, we demonstrate individual performance is conditional on group composition, indicating how social selection may drive behavioral differentiation between individuals. Copyright © 2017 The Author(s). Published by

  7. Individual differences in personality predict how people look at faces.

    Science.gov (United States)

    Perlman, Susan B; Morris, James P; Vander Wyk, Brent C; Green, Steven R; Doyle, Jaime L; Pelphrey, Kevin A

    2009-06-22

    Determining the ways in which personality traits interact with contextual determinants to shape social behavior remains an important area of empirical investigation. The specific personality trait of neuroticism has been related to characteristic negative emotionality and associated with heightened attention to negative, emotionally arousing environmental signals. However, the mechanisms by which this personality trait may shape social behavior remain largely unspecified. We employed eye tracking to investigate the relationship between characteristics of visual scanpaths in response to emotional facial expressions and individual differences in personality. We discovered that the amount of time spent looking at the eyes of fearful faces was positively related to neuroticism. This finding is discussed in relation to previous behavioral research relating personality to selective attention for trait-congruent emotional information, neuroimaging studies relating differences in personality to amygdala reactivity to socially relevant stimuli, and genetic studies suggesting linkages between the serotonin transporter gene and neuroticism. We conclude that personality may be related to interpersonal interaction by shaping aspects of social cognition as basic as eye contact. In this way, eye gaze represents a possible behavioral link in a complex relationship between genes, brain function, and personality.

  8. Individual differences in personality predict how people look at faces.

    Directory of Open Access Journals (Sweden)

    Susan B Perlman

    2009-06-01

    Full Text Available Determining the ways in which personality traits interact with contextual determinants to shape social behavior remains an important area of empirical investigation. The specific personality trait of neuroticism has been related to characteristic negative emotionality and associated with heightened attention to negative, emotionally arousing environmental signals. However, the mechanisms by which this personality trait may shape social behavior remain largely unspecified.We employed eye tracking to investigate the relationship between characteristics of visual scanpaths in response to emotional facial expressions and individual differences in personality. We discovered that the amount of time spent looking at the eyes of fearful faces was positively related to neuroticism.This finding is discussed in relation to previous behavioral research relating personality to selective attention for trait-congruent emotional information, neuroimaging studies relating differences in personality to amygdala reactivity to socially relevant stimuli, and genetic studies suggesting linkages between the serotonin transporter gene and neuroticism. We conclude that personality may be related to interpersonal interaction by shaping aspects of social cognition as basic as eye contact. In this way, eye gaze represents a possible behavioral link in a complex relationship between genes, brain function, and personality.

  9. Individual differences in heart rate variability are associated with the avoidance of negative emotional events.

    Science.gov (United States)

    Katahira, Kentaro; Fujimura, Tomomi; Matsuda, Yoshi-Taka; Okanoya, Kazuo; Okada, Masato

    2014-12-01

    Although the emotional outcome of a choice generally affects subsequent decisions, humans can inhibit the influence of emotion. Heart rate variability (HRV) has emerged as an objective measure of individual differences in the capacity for inhibitory control. In the present study, we investigated how individual differences in HRV at rest are associated with the emotional effects of the outcome of a choice on subsequent decision making using a decision-making task in which emotional pictures appeared as decision outcomes. We used a reinforcement learning model to characterize the observed behaviors according to several parameters, namely, the learning rate and the motivational value of positive and negative pictures. Consequently, we found that individuals with a lower resting HRV exhibited a greater negative motivational value in response to negative pictures, suggesting that these individuals tend to avoid negative pictures compared with individuals with a higher resting HRV. Copyright © 2014 Elsevier B.V. All rights reserved.

  10. Dissociative tendencies and individual differences in high hypnotic suggestibility.

    Science.gov (United States)

    Terhune, Devin Blair; Cardeña, Etzel; Lindgren, Magnus

    2011-03-01

    Inconsistencies in the relationship between dissociation and hypnosis may result from heterogeneity among highly suggestible individuals, in particular the existence of distinct highly suggestible subtypes that are of relevance to models of psychopathology and the consequences of trauma. This study contrasted highly suggestible subtypes high or low in dissociation on measures of hypnotic responding, cognitive functioning, and psychopathology. Twenty-one low suggestible (LS), 19 low dissociative highly suggestible (LDHS), and 11 high dissociative highly suggestible (HDHS) participants were administered hypnotic suggestibility scales and completed measures of free recall, working memory capacity, imagery, fantasy-proneness, psychopathology, and exposure to stressful life events. HDHS participants were more responsive to positive and negative hallucination suggestions and experienced greater involuntariness during hypnotic responding. They also exhibited impaired working memory capacity, elevated pathological fantasy and dissociative symptomatology, and a greater incidence of exposure to stressful life events. In contrast, LDHS participants displayed superior object visual imagery. These results provide further evidence for two highly suggestible subtypes: a dissociative subtype characterised by deficits in executive functioning and a predisposition to psychopathology, and a subtype that exhibits superior imagery and no observable deficits in functioning.

  11. Individual differences in nonverbal number skills predict math anxiety.

    Science.gov (United States)

    Lindskog, Marcus; Winman, Anders; Poom, Leo

    2017-02-01

    Math anxiety (MA) involves negative affect and tension when solving mathematical problems, with potentially life-long consequences. MA has been hypothesized to be a consequence of negative learning experiences and cognitive predispositions. Recent research indicates genetic and neurophysiological links, suggesting that MA stems from a basic level deficiency in symbolic numerical processing. However, the contribution of evolutionary ancient purely nonverbal processes is not fully understood. Here we show that the roots of MA may go beyond symbolic numbers. We demonstrate that MA is correlated with precision of the Approximate Number System (ANS). Individuals high in MA have poorer ANS functioning than those low in MA. This correlation remains significant when controlling for other forms of anxiety and for cognitive variables. We show that MA mediates the documented correlation between ANS precision and math performance, both with ANS and with math performance as independent variable in the mediation model. In light of our results, we discuss the possibility that MA has deep roots, stemming from a non-verbal number processing deficiency. The findings provide new evidence advancing the theoretical understanding of the developmental etiology of MA. Copyright © 2016 Elsevier B.V. All rights reserved.

  12. Modelling biological invasions: Individual to population scales at interfaces

    KAUST Repository

    Belmonte-Beitia, J.

    2013-10-01

    Extracting the population level behaviour of biological systems from that of the individual is critical in understanding dynamics across multiple scales and thus has been the subject of numerous investigations. Here, the influence of spatial heterogeneity in such contexts is explored for interfaces with a separation of the length scales characterising the individual and the interface, a situation that can arise in applications involving cellular modelling. As an illustrative example, we consider cell movement between white and grey matter in the brain which may be relevant in considering the invasive dynamics of glioma. We show that while one can safely neglect intrinsic noise, at least when considering glioma cell invasion, profound differences in population behaviours emerge in the presence of interfaces with only subtle alterations in the dynamics at the individual level. Transport driven by local cell sensing generates predictions of cell accumulations along interfaces where cell motility changes. This behaviour is not predicted with the commonly used Fickian diffusion transport model, but can be extracted from preliminary observations of specific cell lines in recent, novel, cryo-imaging. Consequently, these findings suggest a need to consider the impact of individual behaviour, spatial heterogeneity and especially interfaces in experimental and modelling frameworks of cellular dynamics, for instance in the characterisation of glioma cell motility. © 2013 Elsevier Ltd.

  13. Modelling biological invasions: Individual to population scales at interfaces

    KAUST Repository

    Belmonte-Beitia, J.; Woolley, T.E.; Scott, J.G.; Maini, P.K.; Gaffney, E.A.

    2013-01-01

    Extracting the population level behaviour of biological systems from that of the individual is critical in understanding dynamics across multiple scales and thus has been the subject of numerous investigations. Here, the influence of spatial heterogeneity in such contexts is explored for interfaces with a separation of the length scales characterising the individual and the interface, a situation that can arise in applications involving cellular modelling. As an illustrative example, we consider cell movement between white and grey matter in the brain which may be relevant in considering the invasive dynamics of glioma. We show that while one can safely neglect intrinsic noise, at least when considering glioma cell invasion, profound differences in population behaviours emerge in the presence of interfaces with only subtle alterations in the dynamics at the individual level. Transport driven by local cell sensing generates predictions of cell accumulations along interfaces where cell motility changes. This behaviour is not predicted with the commonly used Fickian diffusion transport model, but can be extracted from preliminary observations of specific cell lines in recent, novel, cryo-imaging. Consequently, these findings suggest a need to consider the impact of individual behaviour, spatial heterogeneity and especially interfaces in experimental and modelling frameworks of cellular dynamics, for instance in the characterisation of glioma cell motility. © 2013 Elsevier Ltd.

  14. Individual Differences in Accurately Judging Personality From Text.

    Science.gov (United States)

    Hall, Judith A; Goh, Jin X; Mast, Marianne Schmid; Hagedorn, Christian

    2016-08-01

    This research examines correlates of accuracy in judging Big Five traits from first-person text excerpts. Participants in six studies were recruited from psychology courses or online. In each study, participants performed a task of judging personality from text and performed other ability tasks and/or filled out questionnaires. Participants who were more accurate in judging personality from text were more likely to be female; had personalities that were more agreeable, conscientious, and feminine, and less neurotic and dominant (all controlling for participant gender); scored higher on empathic concern; self-reported more interest in, and attentiveness to, people's personalities in their daily lives; and reported reading more for pleasure, especially fiction. Accuracy was not associated with SAT scores but had a significant relation to vocabulary knowledge. Accuracy did not correlate with tests of judging personality and emotion based on audiovisual cues. This research is the first to address individual differences in accurate judgment of personality from text, thus adding to the literature on correlates of the good judge of personality. © 2015 Wiley Periodicals, Inc.

  15. Personality, emotion, and individual differences in physiological responses.

    Science.gov (United States)

    Stemmler, Gerhard; Wacker, Jan

    2010-07-01

    A dominant paradigm in biopsychological personality research seeks to establish links between emotional and motivational traits and habitual, transsituationally consistent individual differences in measures of physiological activity. An alternative approach conceptualizes traits as dispositions that are only operative in certain situational contexts and consequently predicts associations between emotional and motivational traits and physiological activity only for trait-relevant situational contexts in which the physiological systems underlying the traits in question are engaged. In the present paper we first examine and contrast these personistic and interactionistic conceptualizations of personality and personality-physiology associations and then present data from several large studies (N>100) in which electrocortical (e.g., frontal alpha asymmetry) and somatovisceral parameters were measured in various situational contexts (e.g., after the induction of either anger, or fear, or anxiety). As predicted by the interactionistic conceptualization of traits as dispositions the situational context and its subjective representation by the participants moderated the personality-physiology relationships for measures of both central and peripheral nervous system activity. We conclude by outlining the implications of the interactionistic approach for biopsychological personality research. Copyright © 2009 Elsevier B.V. All rights reserved.

  16. Defining the biological bases of individual differences in musicality.

    Science.gov (United States)

    Gingras, Bruno; Honing, Henkjan; Peretz, Isabelle; Trainor, Laurel J; Fisher, Simon E

    2015-03-19

    Advances in molecular technologies make it possible to pinpoint genomic factors associated with complex human traits. For cognition and behaviour, identification of underlying genes provides new entry points for deciphering the key neurobiological pathways. In the past decade, the search for genetic correlates of musicality has gained traction. Reports have documented familial clustering for different extremes of ability, including amusia and absolute pitch (AP), with twin studies demonstrating high heritability for some music-related skills, such as pitch perception. Certain chromosomal regions have been linked to AP and musical aptitude, while individual candidate genes have been investigated in relation to aptitude and creativity. Most recently, researchers in this field started performing genome-wide association scans. Thus far, studies have been hampered by relatively small sample sizes and limitations in defining components of musicality, including an emphasis on skills that can only be assessed in trained musicians. With opportunities to administer standardized aptitude tests online, systematic large-scale assessment of musical abilities is now feasible, an important step towards high-powered genome-wide screens. Here, we offer a synthesis of existing literatures and outline concrete suggestions for the development of comprehensive operational tools for the analysis of musical phenotypes. © 2015 The Author(s) Published by the Royal Society. All rights reserved.

  17. Defining the biological bases of individual differences in musicality

    Science.gov (United States)

    Gingras, Bruno; Honing, Henkjan; Peretz, Isabelle; Trainor, Laurel J.; Fisher, Simon E.

    2015-01-01

    Advances in molecular technologies make it possible to pinpoint genomic factors associated with complex human traits. For cognition and behaviour, identification of underlying genes provides new entry points for deciphering the key neurobiological pathways. In the past decade, the search for genetic correlates of musicality has gained traction. Reports have documented familial clustering for different extremes of ability, including amusia and absolute pitch (AP), with twin studies demonstrating high heritability for some music-related skills, such as pitch perception. Certain chromosomal regions have been linked to AP and musical aptitude, while individual candidate genes have been investigated in relation to aptitude and creativity. Most recently, researchers in this field started performing genome-wide association scans. Thus far, studies have been hampered by relatively small sample sizes and limitations in defining components of musicality, including an emphasis on skills that can only be assessed in trained musicians. With opportunities to administer standardized aptitude tests online, systematic large-scale assessment of musical abilities is now feasible, an important step towards high-powered genome-wide screens. Here, we offer a synthesis of existing literatures and outline concrete suggestions for the development of comprehensive operational tools for the analysis of musical phenotypes. PMID:25646515

  18. Individual differences in children's understanding of inversion and arithmetical skill.

    Science.gov (United States)

    Gilmore, Camilla K; Bryant, Peter

    2006-06-01

    Background and aims. In order to develop arithmetic expertise, children must understand arithmetic principles, such as the inverse relationship between addition and subtraction, in addition to learning calculation skills. We report two experiments that investigate children's understanding of the principle of inversion and the relationship between their conceptual understanding and arithmetical skills. A group of 127 children from primary schools took part in the study. The children were from 2 age groups (6-7 and 8-9 years). Children's accuracy on inverse and control problems in a variety of presentation formats and in canonical and non-canonical forms was measured. Tests of general arithmetic ability were also administered. Children consistently performed better on inverse than control problems, which indicates that they could make use of the inverse principle. Presentation format affected performance: picture presentation allowed children to apply their conceptual understanding flexibly regardless of the problem type, while word problems restricted their ability to use their conceptual knowledge. Cluster analyses revealed three subgroups with different profiles of conceptual understanding and arithmetical skill. Children in the 'high ability' and 'low ability' groups showed conceptual understanding that was in-line with their arithmetical skill, whilst a 3rd group of children had more advanced conceptual understanding than arithmetical skill. The three subgroups may represent different points along a single developmental path or distinct developmental paths. The discovery of the existence of the three groups has important consequences for education. It demonstrates the importance of considering the pattern of individual children's conceptual understanding and problem-solving skills.

  19. Different Epidemic Models on Complex Networks

    International Nuclear Information System (INIS)

    Zhang Haifeng; Small, Michael; Fu Xinchu

    2009-01-01

    Models for diseases spreading are not just limited to SIS or SIR. For instance, for the spreading of AIDS/HIV, the susceptible individuals can be classified into different cases according to their immunity, and similarly, the infected individuals can be sorted into different classes according to their infectivity. Moreover, some diseases may develop through several stages. Many authors have shown that the individuals' relation can be viewed as a complex network. So in this paper, in order to better explain the dynamical behavior of epidemics, we consider different epidemic models on complex networks, and obtain the epidemic threshold for each case. Finally, we present numerical simulations for each case to verify our results.

  20. Lifestyle factors and mortality risk in individuals with diabetes mellitus: are the associations different from those in individuals without diabetes?

    Science.gov (United States)

    Sluik, Diewertje; Boeing, Heiner; Li, Kuanrong; Kaaks, Rudolf; Johnsen, Nina Føns; Tjønneland, Anne; Arriola, Larraitz; Barricarte, Aurelio; Masala, Giovanna; Grioni, Sara; Tumino, Rosario; Ricceri, Fulvio; Mattiello, Amalia; Spijkerman, Annemieke M W; van der A, Daphne L; Sluijs, Ivonne; Franks, Paul W; Nilsson, Peter M; Orho-Melander, Marju; Fhärm, Eva; Rolandsson, Olov; Riboli, Elio; Romaguera, Dora; Weiderpass, Elisabete; Sánchez-Cantalejo, Emilio; Nöthlings, Ute

    2014-01-01

    Thus far, it is unclear whether lifestyle recommendations for people with diabetes should be different from those for the general public. We investigated whether the associations between lifestyle factors and mortality risk differ between individuals with and without diabetes. Within the European Prospective Investigation into Cancer and Nutrition (EPIC), a cohort was formed of 6,384 persons with diabetes and 258,911 EPIC participants without known diabetes. Joint Cox proportional hazard regression models of people with and without diabetes were built for the following lifestyle factors in relation to overall mortality risk: BMI, waist/height ratio, 26 food groups, alcohol consumption, leisure-time physical activity, smoking. Likelihood ratio tests for heterogeneity assessed statistical differences in regression coefficients. Multivariable adjusted mortality risk among individuals with diabetes compared with those without was increased, with an HR of 1.62 (95% CI 1.51, 1.75). Intake of fruit, legumes, nuts, seeds, pasta, poultry and vegetable oil was related to a lower mortality risk, and intake of butter and margarine was related to an increased mortality risk. These associations were significantly different in magnitude from those in diabetes-free individuals, but directions were similar. No differences between people with and without diabetes were detected for the other lifestyle factors. Diabetes status did not substantially influence the associations between lifestyle and mortality risk. People with diabetes may benefit more from a healthy diet, but the directions of association were similar. Thus, our study suggests that lifestyle advice with respect to mortality for patients with diabetes should not differ from recommendations for the general population.

  1. Individual differences in foraging strategies of parasitic sabre-tooth blennies.

    Directory of Open Access Journals (Sweden)

    Andrea Bshary

    Full Text Available Originally, evolutionary game theory typically predicted that optimal behaviour in a given situation is uniform or bimodal. However, the growing evidence that animals behave more variably while individuals may differ consistently in their behaviour, has led to the development of models that predict a distribution of strategies. Here we support the importance of such models in a study on a coral reef fish host-parasite system. Parasitic blennies (Plagiotremus sp. regularly attack other fishes to bite off scales and mucus. Individuals of some victim species react to being bitten with punishing the parasite through aggressive chasing. Our field observations and laboratory experiments show that individual blennies differ markedly in how they incorporate being punished into their foraging decisions. We discuss how these differences may affect the payoff structure and hence the net effect of punishment on punishers and on the appearance of a public good for look-alikes.

  2. INDIVIDUAL DIFFERENCES IN WORKING MEMORY PERFORMANCE: «OVERLOAD» EFFECT

    Directory of Open Access Journals (Sweden)

    Yuri G. Pavlov

    2015-01-01

    Full Text Available The aim of this research is to study the relationship betweenfrontal midline theta rhythm changes and individual differences in working memory performance.Methods. The methods involve behavioural testing on the basis of the program for a presentation of stimulus and registration of answers «PsyTask»; method of EEG (electroencephalography; a technique of measurement of efficiency of working memory; the comparative analysis. Software packages EEGLab for Matlab and Fieldtrip are applied while data processing.Results. After the behavioral test all subjects were separated into 2 groups according to their performance: with «highly productive» and «low productive» memory. Specially prepared author’s complete set of the tasks which complexity varied from average to ultrahigh level was offered to participants of experiment –students and employees of the Ural Federal University and Ural Legal Institute of the Ministry of Internal Affairs. Working memory tasks included sets of verbal stimuli for memorizing in strict order without any mental manipulation and sets of similar stimuli for memorizing in alphabetical order (with manipulations. Measured characteristics of theta-rhythm of EEG during information deduction in memory were compared of two groups’ representatives. The obtained data has shown rather uniform and similar dynamics of decrease in quantity of right answers in process of increasing tasks’ complexity. However, changes of a thetarhythm in different groups had sharply expressed distinctions. «Highly productive» examinees have systematic expansion of a theta-rhythm in the central assignments with stabilisation on the most difficult tasks; «low productive» – while tasks performance of average complexity, a sharp falling of theta-rhythm activity is observed after achievement of its maximum activation.Scientific novelty. The working memory «overload» effect and its EEG correlates are demonstrated on a big sample of

  3. Model and Analysis of Individual Rehearsals

    DEFF Research Database (Denmark)

    Jensen, Kristoffer; Frimodt-Møller, Søren

    2013-01-01

    to the score and the instrument, respectively, when applicable. Via these observations, hypotheses are formed and discussed regarding the development of a musician’s Long Term Memory (LTM) in relation to the score, as well as how much s/he is able to store in Short Term Memory (STM) while playing....... of this attention over time, and discusses how this attention is dependent on the musician’s ability to memorize. A selection of musicians (playing guitar, bass clarinet, or violin) was made to individually rehearse short pieces (by Beethoven and Bach) up to and exceeding 20 times. The musicians were instructed...

  4. Individualism and collectivism: Characterization and differences in two Mexican localities

    OpenAIRE

    Cienfuegos-Martínez, Yessica; Saldívar-Garduño, Alicia; Díaz-Loving, Rolando; Avalos-Montoya, Alejandro

    2017-01-01

    Individualism and collectivism are considered dichotomous cultural syndromes that characterize members of a country and they can be reflected on national identity. An individualistic culture is characterized by promote independence and autonomy, by other hand, a collectivistic culture promotes interdependence between person and his/her reference group, in these cultures the group necessities are most important that the individuals ones. However, the geopolitical boundaries between countries n...

  5. Effects of Individual Differences and Situational Features on Age Differences in Mindless Reading.

    Science.gov (United States)

    Shake, Matthew C; Shulley, Leah J; Soto-Freita, Angelica M

    2016-09-01

    Mindless reading occurs when an individual shifts their attention away from the text and toward other off-task thoughts. This study examined whether previously reported age-related declines in mindless reading episodes are due primarily to (a) situational features related to the text itself (e.g., text genre or interest in the text) and/or (b) individual differences in cognitive ability. Participants read 2 texts written in different genres but about the same topic. During reading, they were randomly probed to indicate whether they were on-task or mind-wandering. They also indicated their perceptions regarding the interest and difficulty of the text, and completed a battery of cognitive ability measures. The results showed that (a) text genre may engender some age differences in mindless reading and (b) greater age and perceived interest in the text were each uniquely predictive of reduced mindless reading for both text genres. Individual differences in cognitive abilities (e.g., working memory, vocabulary) did not account for additional significant variance in mindless reading after interest and age were taken into account. Our findings are discussed in terms of implications for age differences in lapses of attention during reading and predictors of mind-wandering generally. © The Author 2015. Published by Oxford University Press on behalf of The Gerontological Society of America. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  6. Determinants of Success in Native and Non-Native Listening Comprehension: An Individual Differences Approach

    Science.gov (United States)

    Andringa, Sible; Olsthoorn, Nomi; van Beuningen, Catherine; Schoonen, Rob; Hulstijn, Jan

    2012-01-01

    The goal of this study was to explain individual differences in both native and non-native listening comprehension; 121 native and 113 non-native speakers of Dutch were tested on various linguistic and nonlinguistic cognitive skills thought to underlie listening comprehension. Structural equation modeling was used to identify the predictors of…

  7. Individual Differences in Visual Word Recognition: Insights from the English Lexicon Project

    Science.gov (United States)

    Yap, Melvin J.; Balota, David A.; Sibley, Daragh E.; Ratcliff, Roger

    2012-01-01

    Empirical work and models of visual word recognition have traditionally focused on group-level performance. Despite the emphasis on the prototypical reader, there is clear evidence that variation in reading skill modulates word recognition performance. In the present study, we examined differences among individuals who contributed to the English…

  8. Individual differences in embracing negatively valenced art: The roles of openness and sensation seeking.

    Science.gov (United States)

    Fayn, Kirill; Kuppens, Peter

    2017-01-01

    We elaborate on the role of individual differences in the processing mechanisms outlined by the Distancing-Embracing model. The role of openness is apparent in appreciating meaning-making art that elicits interest, feeling moved, and mixed emotions. The influence of sensation seeking is likely to manifest in thrill-chasing art that draws on the arousing interplay of positive and negative emotions.

  9. Speed and Lateral Inhibition of Stimulus Processing Contribute to Individual Differences in Stroop-Task Performance.

    Science.gov (United States)

    Naber, Marnix; Vedder, Anneke; Brown, Stephen B R E; Nieuwenhuis, Sander

    2016-01-01

    The Stroop task is a popular neuropsychological test that measures executive control. Strong Stroop interference is commonly interpreted in neuropsychology as a diagnostic marker of impairment in executive control, possibly reflecting executive dysfunction. However, popular models of the Stroop task indicate that several other aspects of color and word processing may also account for individual differences in the Stroop task, independent of executive control. Here we use new approaches to investigate the degree to which individual differences in Stroop interference correlate with the relative processing speed of word and color stimuli, and the lateral inhibition between visual stimuli. We conducted an electrophysiological and behavioral experiment to measure (1) how quickly an individual's brain processes words and colors presented in isolation (P3 latency), and (2) the strength of an individual's lateral inhibition between visual representations with a visual illusion. Both measures explained at least 40% of the variance in Stroop interference across individuals. As these measures were obtained in contexts not requiring any executive control, we conclude that the Stroop effect also measures an individual's pre-set way of processing visual features such as words and colors. This study highlights the important contributions of stimulus processing speed and lateral inhibition to individual differences in Stroop interference, and challenges the general view that the Stroop task primarily assesses executive control.

  10. Comparative study of different surrogate markers for individual radiation sensitivity

    International Nuclear Information System (INIS)

    Hoffmann, Nele Julia

    2013-01-01

    Radiotherapy is an important part of therapeutic tumor treatment concept. The applied total dose is limited by the unavoidable radiation effect on the surrounding normal tissue and the risk of radiation induced acute or chronic side effects. The clinical radiation sensitivity, i.e. the risk of radiogenic side effects is strongly coupled to the cellular radiation sensitivity. The contribution is focused on the development of a predictive tool for the individual radiation sensitivity for individual radiotherapeutic planning using lymphocytes. Residual foci, i.e. accumulated repair associated proteins at the residual double strand break are supposed to be surrogate markers of the cellular radiation sensitivity. No relation between the foci detection and the G(0)/G(1) was found assay with respect to the individual radiation sensitivity.

  11. Consideration of sample heterogeneity and in-depth analysis of individual differences in sensory analysis

    DEFF Research Database (Denmark)

    Bavay, Cécile; Brockhoff, Per B.; Kuznetsova, Alexandra

    2014-01-01

    In descriptive sensory analysis, large variations may be observed between scores. Individual differences between assessors have been identified as one cause for these variations. Much work has been done on modeling these differences and accounting for them through analysis of variance (ANOVA). When......, an extended version of the assessor model approach is applied. The data set used in the paper is based on sensory evaluations of three apple samples scored by a panel of 19 assessors using seven descriptors in four replicates. The application of the extended assessor model approach to unbalanced data provides...

  12. Individual differences in attention strategies during detection, fine discrimination, and coarse discrimination

    Science.gov (United States)

    Hecker, Elizabeth A.; Serences, John T.; Srinivasan, Ramesh

    2013-01-01

    Interacting with the environment requires the ability to flexibly direct attention to relevant features. We examined the degree to which individuals attend to visual features within and across Detection, Fine Discrimination, and Coarse Discrimination tasks. Electroencephalographic (EEG) responses were measured to an unattended peripheral flickering (4 or 6 Hz) grating while individuals (n = 33) attended to orientations that were offset by 0°, 10°, 20°, 30°, 40°, and 90° from the orientation of the unattended flicker. These unattended responses may be sensitive to attentional gain at the attended spatial location, since attention to features enhances early visual responses throughout the visual field. We found no significant differences in tuning curves across the three tasks in part due to individual differences in strategies. We sought to characterize individual attention strategies using hierarchical Bayesian modeling, which grouped individuals into families of curves that reflect attention to the physical target orientation (“on-channel”) or away from the target orientation (“off-channel”) or a uniform distribution of attention. The different curves were related to behavioral performance; individuals with “on-channel” curves had lower thresholds than individuals with uniform curves. Individuals with “off-channel” curves during Fine Discrimination additionally had lower thresholds than those assigned to uniform curves, highlighting the perceptual benefits of attending away from the physical target orientation during fine discriminations. Finally, we showed that a subset of individuals with optimal curves (“on-channel”) during Detection also demonstrated optimal curves (“off-channel”) during Fine Discrimination, indicating that a subset of individuals can modulate tuning optimally for detection and discrimination. PMID:23678013

  13. Individual Differences in Learning from an Intelligent Discovery World: Smithtown.

    Science.gov (United States)

    Shute, Valerie J.

    "Smithtown" is an intelligent computer program designed to enhance an individual's scientific inquiry skills as well as to provide an environment for learning principles of basic microeconomics. It was hypothesized that intelligent computer instruction on applying effective interrogative skills (e.g., changing one variable at a time…

  14. Dissociable mechanisms underlying individual differences in visual working memory capacity

    NARCIS (Netherlands)

    Gulbinaite, Rasa; Johnson, Addie; de Jong, Ritske; Morey, Candice C.; van Rijn, Hedderik

    2014-01-01

    Individuals scoring relatively high on measures of working memory tend to be more proficient at controlling attention to minimize the effect of distracting information. It is currently unknown whether such superior attention control abilities are mediated by stronger suppression of irrelevant

  15. Generalization of Individual Differences in Second Language Learning

    Science.gov (United States)

    Anjum, Amber Nasreen; Al-Othmany, Dheya Shujaa; Hussain, Ahmad

    2015-01-01

    This commentary is based on the analyses of the participants' responses provided in written form while filling the questionnaires. The purpose of the study was to identify and analyze factors in individuals' experiences about second language acquisition. The study was conducted through a research questionnaire. The questions were designed for…

  16. Maintaining activity engagement: individual differences in the process of self-regulating motivation.

    Science.gov (United States)

    Sansone, Carol; Thoman, Dustin B

    2006-12-01

    Typically, models of self-regulation include motivation in terms of goals. Motivation is proposed to differ among individuals as a consequence of the goals they hold as well as how much they value those goals and expect to attain them. We suggest that goal-defined motivation is only one source of motivation critical for sustained engagement. A second source is the motivation that arises from the degree of interest experienced in the process of goal pursuit. Our model integrates both sources of motivation within the goal-striving process and suggests that individuals may actively monitor and regulate them. Conceptualizing motivation in terms of a self-regulatory process provides an organizing framework for understanding how individuals might differ in whether they experience interest while working toward goals, whether they persist without interest, and whether and how they try to create interest. We first present the self-regulation of motivation model and then review research illustrating how the consideration of individual differences at different points in the process allows a better understanding of variability in people's choices, efforts, and persistence over time.

  17. Correlates of individual, and age-related, differences in short-term learning☆

    OpenAIRE

    Zhang, Zhiyong; Davis, Hasker P.; Salthouse, Timothy A.; Tucker-Drob, Elliot M.

    2007-01-01

    Latent growth models were applied to data on multitrial verbal and spatial learning tasks from two independent studies. Although significant individual differences in both initial level of performance and subsequent learning were found in both tasks, age differences were found only in mean initial level, and not in mean learning. In neither task was fluid or crystallized intelligence associated with learning. Although there were moderate correlations among the level parameters across the verb...

  18. INDIVIDUAL-BASED MODELS: POWERFUL OR POWER STRUGGLE?

    Science.gov (United States)

    Willem, L; Stijven, S; Hens, N; Vladislavleva, E; Broeckhove, J; Beutels, P

    2015-01-01

    Individual-based models (IBMs) offer endless possibilities to explore various research questions but come with high model complexity and computational burden. Large-scale IBMs have become feasible but the novel hardware architectures require adapted software. The increased model complexity also requires systematic exploration to gain thorough system understanding. We elaborate on the development of IBMs for vaccine-preventable infectious diseases and model exploration with active learning. Investment in IBM simulator code can lead to significant runtime reductions. We found large performance differences due to data locality. Sorting the population once, reduced simulation time by a factor two. Storing person attributes separately instead of using person objects also seemed more efficient. Next, we improved model performance up to 70% by structuring potential contacts based on health status before processing disease transmission. The active learning approach we present is based on iterative surrogate modelling and model-guided experimentation. Symbolic regression is used for nonlinear response surface modelling with automatic feature selection. We illustrate our approach using an IBM for influenza vaccination. After optimizing the parameter spade, we observed an inverse relationship between vaccination coverage and the clinical attack rate reinforced by herd immunity. These insights can be used to focus and optimise research activities, and to reduce both dimensionality and decision uncertainty.

  19. Individual differences in current events knowledge: contributions of ability, personality, and interests.

    Science.gov (United States)

    Hambrick, David Z; Meinz, Elizabeth J; Oswald, Frederick L

    2007-03-01

    What accounts for individual differences in the sort of knowledge that people may draw on in everyday cognitive tasks, such as deciding whom to vote for in a presidential election, how to invest money in the stock market, or what team to bet on in a friendly wager? In a large sample of undergraduate students, we investigated correlates of individual differences in recently acquired knowledge of current events in domains such as politics, business, and sports. Structural equation modeling revealed two predictive pathways: one involving cognitive ability factors and the other involving two major nonability factors (personality and interests). The results of this study add to what is known about the sources of individual differences in knowledge and are interpreted in the context of theoretical conceptions of adult intelligence that emphasize the centrality and importance of knowledge (e.g., Ackerman, 1996; Cattell, 1971).

  20. Design of Individualized Wheelchairs Using AHP and Kano Model

    Directory of Open Access Journals (Sweden)

    Yanli Yuan

    2014-06-01

    Full Text Available To study how to design different grades of individualized wheelchairs according to users' needs, a personalized wheelchair design method based on AHP and Kano model is proposed. The AHP model determines the relative importance of characteristics of customers' demands. The subfunctions of manual wheelchairs and their attributes are given. The weight coefficients are calculated. 20 experts (10 are the members of the research team, 5 are doctors, and 5 are wheelchair designers are involved in the above two parts of the work. Kano model represents the types of user requirements. 30 participants' (wheelchair users needs are divided into 5 categories: M, O, E, I, and R. According to the types of user needs and the weight of each subfunction, three manual wheelchair models are built. Traditional design method usually cannot satisfy the requirements of users and product structure, so this paper makes a contribution to solve this problem. The method can be used to design individualized wheelchairs which may improve the product quality and customers' satisfaction. Meanwhile it also can reduce the design time, thereby reducing the design cost.

  1. Physiological and psychological individual differences influence resting brain function measured by ASL perfusion.

    Science.gov (United States)

    Kano, M; Coen, S J; Farmer, A D; Aziz, Q; Williams, S C R; Alsop, D C; Fukudo, S; O'Gorman, R L

    2014-09-01

    Effects of physiological and/or psychological inter-individual differences on the resting brain state have not been fully established. The present study investigated the effects of individual differences in basal autonomic tone and positive and negative personality dimensions on resting brain activity. Whole-brain resting cerebral perfusion images were acquired from 32 healthy subjects (16 males) using arterial spin labeling perfusion MRI. Neuroticism and extraversion were assessed with the Eysenck Personality Questionnaire-Revised. Resting autonomic activity was assessed using a validated measure of baseline cardiac vagal tone (CVT) in each individual. Potential associations between the perfusion data and individual CVT (27 subjects) and personality score (28 subjects) were tested at the level of voxel clusters by fitting a multiple regression model at each intracerebral voxel. Greater baseline perfusion in the dorsal anterior cingulate cortex (ACC) and cerebellum was associated with lower CVT. At a corrected significance threshold of p individual autonomic tone and psychological variability influence resting brain activity in brain regions, previously shown to be associated with autonomic arousal (dorsal ACC) and personality traits (amygdala, caudate, etc.) during active task processing. The resting brain state may therefore need to be taken into account when interpreting the neurobiology of individual differences in structural and functional brain activity.

  2. The Impact on Individualizing Student Models on Necessary Practice Opportunities

    Science.gov (United States)

    Lee, Jung In; Brunskill, Emma

    2012-01-01

    When modeling student learning, tutors that use the Knowledge Tracing framework often assume that all students have the same set of model parameters. We find that when fitting parameters to individual students, there is significant variation among the individual's parameters. We examine if this variation is important in terms of instructional…

  3. Numbers in action: individual differences and interactivity in mental arithmetic.

    Science.gov (United States)

    Guthrie, Lisa G; Vallée-Tourangeau, Frédéric

    2018-02-03

    Previous research indicates that interactive arithmetic tasks may alleviate the deleterious impact of maths anxiety on arithmetic performance. Our aim here was to further test the impact of interactivity on maths-anxious individuals and those with poorer numeracy skills. In the experiment reported here participants completed sums in two interactivity contexts. In a low-interactivity condition, sums were completed with hands down. In a second, high-interactivity condition, participants used moveable number tokens. As anticipated, accuracy and efficiency were greater in the high compared to the low-interactivity condition. Correlational analyses indicated that maths anxiety, objective numeracy, measures of maths expertise and working memory were stronger predictors of performance in the low- than in the high-interactivity conditions. Interactivity transformed the deployment of arithmetic skills, improved performance, and reduced the gap between high- and low-ability individuals. These findings suggest that traditional psychometric efforts that identify the cognitive capacities and dispositions involved in mental arithmetic should take into account the degree of interactivity afforded by the task environment.

  4. Individualism and collectivism: what differences between Portuguese and Romanian adolescents?

    Science.gov (United States)

    Ciochină, Laura; Faria, Luísa

    2009-11-01

    This article presents the results of a series of preliminary comparisons, between the Portuguese and Romanian cultural contexts, on the individualism-collectivism (IND/COL) cultural dimension. The IND/COL was evaluated with the Individualism-Collectivism Questionnaire - ICQ -, constructed in New Zealand by Shulruf, Hattie and Dixon (2003, Anonymous Questionnaire of Self-Attitudes - AQSA), and adapted to the Portuguese and Romanian contexts by Ciochină and Faria (2007), using studies of confirmatory factor analysis. The ICQ composed by 26 items, 15 evaluating the IND scale--with three subscales (Uniqueness, Competition and Responsibility)--, and 11 evaluating the COL scale--with two subscales (Harmony and Advice)--, was administered to 395 subjects, 200 Portuguese and 195 Romanian, 10th and 12th graders. On the whole, in the Portuguese and Romanian samples, the multivariate and univariate statistical analyses evidenced the existence of two independent variables--gender and cultural context--, with significant effects, main and of interaction, on the scales and subscales of the ICQ. The results were discussed taking into consideration the specificities of the educational systems in the two cultural contexts, which are inevitably shaped by socio-cultural factors characteristic of the two countries considered in the present study--Portugal and Romania.

  5. Individual differences in implicit motor learning: task specificity in sensorimotor adaptation and sequence learning.

    Science.gov (United States)

    Stark-Inbar, Alit; Raza, Meher; Taylor, Jordan A; Ivry, Richard B

    2017-01-01

    In standard taxonomies, motor skills are typically treated as representative of implicit or procedural memory. We examined two emblematic tasks of implicit motor learning, sensorimotor adaptation and sequence learning, asking whether individual differences in learning are correlated between these tasks, as well as how individual differences within each task are related to different performance variables. As a prerequisite, it was essential to establish the reliability of learning measures for each task. Participants were tested twice on a visuomotor adaptation task and on a sequence learning task, either the serial reaction time task or the alternating reaction time task. Learning was evident in all tasks at the group level and reliable at the individual level in visuomotor adaptation and the alternating reaction time task but not in the serial reaction time task. Performance variability was predictive of learning in both domains, yet the relationship was in the opposite direction for adaptation and sequence learning. For the former, faster learning was associated with lower variability, consistent with models of sensorimotor adaptation in which learning rates are sensitive to noise. For the latter, greater learning was associated with higher variability and slower reaction times, factors that may facilitate the spread of activation required to form predictive, sequential associations. Interestingly, learning measures of the different tasks were not correlated. Together, these results oppose a shared process for implicit learning in sensorimotor adaptation and sequence learning and provide insight into the factors that account for individual differences in learning within each task domain. We investigated individual differences in the ability to implicitly learn motor skills. As a prerequisite, we assessed whether individual differences were reliable across test sessions. We found that two commonly used tasks of implicit learning, visuomotor adaptation and the

  6. Gifted and talented children: heterogeneity and individual differences

    Directory of Open Access Journals (Sweden)

    María Pereira Da Costa

    Full Text Available Giftedness is a large topic, covering many domains of activity and diverse manifestations. In this paper, we examine two specific topics: (a cognitive profiles of gifted children and, (b musical talent development. The common point of these studies is the observation of the heterogeneity of individual profiles. The results of the first study performed on 99 children with an IQ equal to or higher than 130, shows a large heterogeneity in intellectual potential, which is masked if we look only on the overall IQ. A hierarchical clustering analysis identifies six classes of children with contrasting means profiles. The second study is an exploratory research, in which we try to describe the environment of music pupils and to evaluate the importance that parents and teachers give to the main success factors for musical training. Our results highlight several differentiated profiles relating to the contexts of training, centred on the representation that the child has of music.

  7. Injury risk is different in team and individual youth sport.

    Science.gov (United States)

    Theisen, Daniel; Frisch, Anne; Malisoux, Laurent; Urhausen, Axel; Croisier, Jean-Louis; Seil, Romain

    2013-05-01

    This study compared sports injury incidence in young high-level athletes from various team and individual sports and investigated if sport participation patterns are linked to injuries. Prospective cohort follow-up. Pupils from a public sports school (12-19 years) were recruited over two separate school years (2008-2009: 42 weeks, n=199 athletes; 2009-2010: 40 weeks, n=89 athletes). Training and competition volume and intensity were recorded via a personal sports diary. Sports injuries (time-loss definition) were registered by medical staff members using a standardized questionnaire. Injury incidence was significantly higher in team compared with individual sports (6.16 versus 2.88 injuries/1000h, respectively), as a result of a higher incidence of both traumatic (RR=2.17; CI95%=1.75-2.70; pteam sports participation had a hazard ratio of 2.00 (CI95%=1.49-2.68; psports, with additionally previous injury being a risk and age a protective factor. The number of competitions per 100 days was significantly higher in team sports, whereas the number of intense training sessions per 100 days was significantly lower. In team sports, the number of competitions per 100 days was positively associated with injuries (HR=1.072; CI95% [1.033; 1.113]; psports the number of competitions per 100 days had a protective effect (HR=0.940; CI95% [0.893; 0.989]; p=0.017). Team sports participation entailed a higher injury risk, whatever the injury category. Further research should elucidate the role of characteristics related to sport participation in injury causation. Copyright © 2012 Sports Medicine Australia. Published by Elsevier Ltd. All rights reserved.

  8. Individual differences in detecting rapidly presented fearful faces.

    Directory of Open Access Journals (Sweden)

    Dandan Zhang

    Full Text Available Rapid detection of evolutionarily relevant threats (e.g., fearful faces is important for human survival. The ability to rapidly detect fearful faces exhibits high variability across individuals. The present study aimed to investigate the relationship between behavioral detection ability and brain activity, using both event-related potential (ERP and event-related oscillation (ERO measurements. Faces with fearful or neutral facial expressions were presented for 17 ms or 200 ms in a backward masking paradigm. Forty-two participants were required to discriminate facial expressions of the masked faces. The behavioral sensitivity index d' showed that the detection ability to rapidly presented and masked fearful faces varied across participants. The ANOVA analyses showed that the facial expression, hemisphere, and presentation duration affected the grand-mean ERP (N1, P1, and N170 and ERO (below 20 Hz and lasted from 100 ms to 250 ms post-stimulus, mainly in theta band brain activity. More importantly, the overall detection ability of 42 subjects was significantly correlated with the emotion effect (i.e., fearful vs. neutral on ERP (r = 0.403 and ERO (r = 0.552 measurements. A higher d' value was corresponding to a larger size of the emotional effect (i.e., fearful--neutral of N170 amplitude and a larger size of the emotional effect of the specific ERO spectral power at the right hemisphere. The present results suggested a close link between behavioral detection ability and the N170 amplitude as well as the ERO spectral power below 20 Hz in individuals. The emotional effect size between fearful and neutral faces in brain activity may reflect the level of conscious awareness of fearful faces.

  9. An Empirical Investigation of Individual Differences in Time to Learn

    Science.gov (United States)

    Anderson, Lorin W.

    1976-01-01

    Results show that student differences in time-on-task to learn to criterion are alterable and can be minimized over a sequence of learning units given appropriate adaptive learning strategies. (Author/DEP)

  10. Classification of emotions by multivariate analysis and individual differences of nuclear power plant operators' emotion

    International Nuclear Information System (INIS)

    Hasegawa, Naoko; Yoshimura, Seiichi

    1999-01-01

    The purpose of this study is the development of a simulation model which expresses operators' emotion under plant emergency. This report shows the classification of emotions by multivariate analysis and investigation results conducted to clarify individual differences of activated emotion influenced by personal traits. Although a former investigation was conducted to classify emotions into five basic emotions proposed by Johnson-Laird, the basic emotions was not based on real data. For the development of more realistic and accurate simulation model, it is necessary to recognize basic emotion and to classify emotions into them. As a result of analysis by qualification method 3 and cluster analysis, four basic clusters were clarified, i.e., Emotion expressed towards objects, Emotion affected by objects, Pleasant emotion, and Surprise. Moreover, 51 emotions were ranked in the order according to their similarities in each cluster. An investigation was conducted to clarify individual differences in emotion process using 87 plant operators. The results showed the differences of emotion depending on the existence of operators' foresight, cognitive style, experience in operation, and consciousness of attribution to an operating team. For example, operators with low self-efficacy, short experience or low consciousness of attribution to a team, feel more intensive emotion under plant emergency and more affected by severe plant conditions. The model which can express individual differences will be developed utilizing and converting these data hereafter. (author)

  11. Classification of emotions by multivariate analysis and individual differences of nuclear power plant operators` emotion

    Energy Technology Data Exchange (ETDEWEB)

    Hasegawa, Naoko; Yoshimura, Seiichi [Central Research Inst. of Electric Power Industry, Tokyo (Japan)

    1999-03-01

    The purpose of this study is the development of a simulation model which expresses operators` emotion under plant emergency. This report shows the classification of emotions by multivariate analysis and investigation results conducted to clarify individual differences of activated emotion influenced by personal traits. Although a former investigation was conducted to classify emotions into five basic emotions proposed by Johnson-Laird, the basic emotions was not based on real data. For the development of more realistic and accurate simulation model, it is necessary to recognize basic emotion and to classify emotions into them. As a result of analysis by qualification method 3 and cluster analysis, four basic clusters were clarified, i.e., Emotion expressed towards objects, Emotion affected by objects, Pleasant emotion, and Surprise. Moreover, 51 emotions were ranked in the order according to their similarities in each cluster. An investigation was conducted to clarify individual differences in emotion process using 87 plant operators. The results showed the differences of emotion depending on the existence of operators` foresight, cognitive style, experience in operation, and consciousness of attribution to an operating team. For example, operators with low self-efficacy, short experience or low consciousness of attribution to a team, feel more intensive emotion under plant emergency and more affected by severe plant conditions. The model which can express individual differences will be developed utilizing and converting these data hereafter. (author)

  12. Individual Differences in Strategy Choices: Good Students, Not-So-Good Students, and Perfectionists.

    Science.gov (United States)

    Siegler, Robert S.

    1988-01-01

    Issues include consistent individual differences in children's strategy choices, interpretation of differences within a framework, and the relation of differences to standardized test performance. (RJC)

  13. The neurotic wandering mind: An individual differences investigation of neuroticism, mind-wandering, and executive control.

    Science.gov (United States)

    Robison, Matthew K; Gath, Katherine I; Unsworth, Nash

    2017-04-01

    Cognitive psychology and cognitive neuroscience have recently developed a keen interest in the phenomenon of mind-wandering. People mind-wander frequently, and mind-wandering is associated with decreased cognitive performance. But why do people mind-wander so much? Previous investigations have focused on cognitive abilities like working memory capacity and attention control. But an individual's tendency to worry, feel anxious, and entertain personal concerns also influences mind-wandering. The Control Failure × Concerns model of mind-wandering. Psychological Bulletin, 136, 188-197] argues that individual differences in the propensity to mind-wander are jointly determined by cognitive abilities and by the presence of personally salient concerns that intrude on task focus. In order to test this model, we investigated individual differences in mind-wandering, executive attention, and personality with a focus on neuroticism. The results showed that neurotic individuals tended to report more mind-wandering during cognitive tasks, lower working memory capacity, and poorer attention control. Thus the trait of neuroticism adds an additional source of variance in the tendency to mind-wander, which offers support for the Control Failure × Concerns model. The results help bridge the fields of clinical psychology, cognitive psychology, affective neuroscience, and cognitive neuroscience as a means of developing a more complete understanding of the complex relationship between cognition, personality, and emotion.

  14. Using eye tracking to test for individual differences in attention to attractive faces.

    Science.gov (United States)

    Valuch, Christian; Pflüger, Lena S; Wallner, Bernard; Laeng, Bruno; Ansorge, Ulrich

    2015-01-01

    We assessed individual differences in visual attention toward faces in relation to their attractiveness via saccadic reaction times. Motivated by the aim to understand individual differences in attention to faces, we tested three hypotheses: (a) Attractive faces hold or capture attention more effectively than less attractive faces; (b) men show a stronger bias toward attractive opposite-sex faces than women; and (c) blue-eyed men show a stronger bias toward blue-eyed than brown-eyed feminine faces. The latter test was included because prior research suggested a high effect size. Our data supported hypotheses (a) and (b) but not (c). By conducting separate tests for disengagement of attention and attention capture, we found that individual differences exist at distinct stages of attentional processing but these differences are of varying robustness and importance. In our conclusion, we also advocate the use of linear mixed effects models as the most appropriate statistical approach for studying inter-individual differences in visual attention with naturalistic stimuli.

  15. Using eye tracking to test for individual differences in attention to attractive faces

    Directory of Open Access Journals (Sweden)

    Christian eValuch

    2015-02-01

    Full Text Available We assessed individual differences in visual attention toward faces in relation to their attractiveness via saccadic reaction times (SRTs. Motivated by the aim to understand individual differences in attention to faces, we tested three hypotheses: (a Attractive faces hold or capture attention more effectively than less attractive faces; (b men show a stronger bias toward attractive opposite-sex faces than women; and (c blue-eyed men show a stronger bias toward blue-eyed than brown-eyed feminine faces. The latter test was included because prior research suggested a high effect size. Our data supported hypotheses (a and (b but not (c. By conducting separate tests for disengagement of attention and attention capture, we found that individual differences exist at distinct stages of attentional processing but these differences are of varying robustness and importance. In our conclusion, we also advocate the use of linear mixed effects models as the most appropriate statistical approach toward studying inter-individual differences in visual attention with naturalistic stimuli.

  16. Individual variation in cone photoreceptor density in house sparrows: implications for between-individual differences in visual resolution and chromatic contrast.

    Science.gov (United States)

    Ensminger, Amanda L; Fernández-Juricic, Esteban

    2014-01-01

    Between-individual variation has been documented in a wide variety of taxa, especially for behavioral characteristics; however, intra-population variation in sensory systems has not received similar attention in wild animals. We measured a key trait of the visual system, the density of retinal cone photoreceptors, in a wild population of house sparrows (Passer domesticus). We tested whether individuals differed from each other in cone densities given within-individual variation across the retina and across eyes. We further tested whether the existing variation could lead to individual differences in two aspects of perception: visual resolution and chromatic contrast. We found consistent between-individual variation in the densities of all five types of avian cones, involved in chromatic and achromatic vision. Using perceptual modeling, we found that this degree of variation translated into significant between-individual differences in visual resolution and the chromatic contrast of a plumage signal that has been associated with mate choice and agonistic interactions. However, there was no evidence for a relationship between individual visual resolution and chromatic contrast. The implication is that some birds may have the sensory potential to perform "better" in certain visual tasks, but not necessarily in both resolution and contrast simultaneously. Overall, our findings (a) highlight the need to consider multiple individuals when characterizing sensory traits of a species, and (b) provide some mechanistic basis for between-individual variation in different behaviors (i.e., animal personalities) and for testing the predictions of several widely accepted hypotheses (e.g., honest signaling).

  17. Effects of individual differences on the efficacy of different distracters during visual sexual stimulation in women.

    Science.gov (United States)

    Roberts, Verena M; Prause, Nicole

    2012-02-01

    Distractions from sexual cues have been shown to decrease the sexual response, but it is unclear how distracters decrease sexual response. Individual differences may modulate the efficacy of distracters. Forty women viewed three sexual films while their labial temperature and continuous self-reported sexual arousal were monitored. One sexual film had simultaneous verbal distracters concerning dissatisfaction with one's physical appearance (higher salience distracter), a second had distracters concerning daily chores (lower salience distracter), and the third sexual film had no distracters. Participant's reporting greater relationship satisfaction and more communication with their partner about their own physical appearance were expected to decrease the efficacy (increased sexual arousal) of the distracters concerning physical appearance. Contrary to expectations, women who received less feedback about their body from their partners reported less sexual arousal during a sexual film with body distracters than a sexual film with general distracters or a sexual film with no distracters. All women exhibited lower labial temperature in Minutes 2 and 3 of the sexual film with body image distracters as compared to the other two sexual films. Possible explanations explored include self-verification theory and individual differences in the indicators that women consider when rating their sexual arousal.

  18. Individual differences in the rubber-hand illusion: predicting self-reports of people's personal experiences.

    Science.gov (United States)

    Haans, Antal; Kaiser, Florian G; Bouwhuis, Don G; Ijsselsteijn, Wijnand A

    2012-10-01

    Can we assess individual differences in the extent to which a person perceives the rubber-hand illusion on the basis of self-reported experiences? In this research, we develop such an instrument using Rasch-type models. In our conception, incorporating an object (e.g., a rubber hand) into one's body image requires various sensorimotor and cognitive processes. The extent to which people can meet these requirements thus determines how intensely people experience and, simultaneously, describe the illusion. As a consequence, individual differences in people's susceptibility to the rubber-hand illusion can be determined by inspecting reports of their personal experiences. The proposed model turned out to be functional in its capability to predict self-reports of people's experiences and to reliably assess individual differences in susceptibility to the illusion. Regarding validity, we found a small, but significant, correlation between individual susceptibility and proprioceptive drift. Additionally, we found that asynchrony, and tapping rather than stroking the fingers constrain the experience of the illusion. Copyright © 2012 Elsevier B.V. All rights reserved.

  19. Multimodal frontostriatal connectivity underlies individual differences in self-esteem.

    Science.gov (United States)

    Chavez, Robert S; Heatherton, Todd F

    2015-03-01

    A heightened sense of self-esteem is associated with a reduced risk for several types of affective and psychiatric disorders, including depression, anxiety and eating disorders. However, little is known about how brain systems integrate self-referential processing and positive evaluation to give rise to these feelings. To address this, we combined diffusion tensor imaging (DTI) and functional magnetic resonance imaging (fMRI) to test how frontostriatal connectivity reflects long-term trait and short-term state aspects of self-esteem. Using DTI, we found individual variability in white matter structural integrity between the medial prefrontal cortex and the ventral striatum was related to trait measures of self-esteem, reflecting long-term stability of self-esteem maintenance. Using fMRI, we found that functional connectivity of these regions during positive self-evaluation was related to current feelings of self-esteem, reflecting short-term state self-esteem. These results provide convergent anatomical and functional evidence that self-esteem is related to the connectivity of frontostriatal circuits and suggest that feelings of self-worth may emerge from neural systems integrating information about the self with positive affect and reward. This information could potentially inform the etiology of diminished self-esteem underlying multiple psychiatric conditions and inform future studies of evaluative self-referential processing. © The Author (2014). Published by Oxford University Press. For Permissions, please email: journals.permissions@oup.com.

  20. Individual differences in fornix microstructure and body mass index.

    Directory of Open Access Journals (Sweden)

    Claudia Metzler-Baddeley

    Full Text Available The prevalence of obesity and associated health conditions is increasing in the developed world. Obesity is related to atrophy and dysfunction of the hippocampus and hippocampal lesions may lead to increased appetite and weight gain. The hippocampus is connected via the fornix tract to the hypothalamus, orbitofrontal cortex, and the nucleus accumbens, all key structures for homeostatic and reward related control of food intake. The present study employed diffusion MRI tractography to investigate the relationship between microstructural properties of the fornix and variation in Body Mass Index (BMI, within normal and overweight ranges, in a group of community-dwelling older adults (53-93 years old. Larger BMI was associated with larger axial and mean diffusivity in the fornix (r = 0.64 and r = 0.55 respectively, relationships that were most pronounced in overweight individuals. Moreover, controlling for age, education, cognitive performance, blood pressure and global brain volume increased these correlations. Similar associations were not found in the parahippocampal cingulum, a comparison temporal association pathway. Thus, microstructural changes in fornix white matter were observed in older adults with increasing BMI levels from within normal to overweight ranges, so are not exclusively related to obesity. We propose that hippocampal-hypothalamic-prefrontal interactions, mediated by the fornix, contribute to the healthy functioning of networks involved in food intake control. The fornix, in turn, may display alterations in microstructure that reflect weight gain.

  1. Second language pragmatic ability: Individual differences according to environment

    Directory of Open Access Journals (Sweden)

    Lauren Wyner

    2015-12-01

    Full Text Available The aims of this paper are to review research literature on the role that the second language (L2 and foreign language (FL environments actually play in the development of learners’ target language (TL pragmatic ability, and also to speculate as to the extent to which individual factors can offset the advantages that learners may have by being in the L2 context while they are learning. The paper starts by defining pragmatics and by problematizing this definition. Then, attention is given to research literature dealing with the learning of pragmatics in an L2 context compared to an FL context. Next, studies on the role of pragmatic transfer are considered, with subsequent attention given to the literature on the incidence of pragmatic transfer in FL as opposed to L2 contexts. Finally, selected studies on the role of motivation in the development of pragmatic ability are examined. In the discussion section, a number of pedagogical suggestions are offered: the inclusion of pragmatics in teacher development, the use of authentic pragmatics materials, motivating learners to be more savvy about pragmatics, and supporting learners in accepting or challenging native-speaker norms. Suggestions as to further research in the field are also offered.

  2. Individual Difference Predictors of Creativity in Art and Science Students

    Science.gov (United States)

    Furnham, Adrian; Batey, Mark; Booth, Tom W.; Patel, Vikita; Lozinskaya, Dariya

    2011-01-01

    Two studies are reported that used multiple measures of creativity to investigate creativity differences and correlates in arts and science students. The first study examined Divergent Thinking fluency, Self-Rated Creativity and Creative Achievement in matched groups of Art and Science students. Arts students scored higher than Science students on…

  3. Individual Difference Theory and Research: Application to Multinational Coalition Teamwork

    Science.gov (United States)

    2008-04-01

    and negatively related to perfectionism, rigidity, dogmatism, and ethnocentrism (see [15; 16] Hannigan, 1990; see also Ward & Kennedy, 1994). There...was not the key to success here. The personnel that staffed the C3IC were selected to understand and communicate with personnel from a different

  4. Sexual orientation related differences in cortical thickness in male individuals.

    Directory of Open Access Journals (Sweden)

    Christoph Abé

    Full Text Available Previous neuroimaging studies demonstrated sex and also sexual orientation related structural and functional differences in the human brain. Genetic information and effects of sex hormones are assumed to contribute to the male/female differentiation of the brain, and similar effects could play a role in processes influencing human's sexual orientation. However, questions about the origin and development of a person's sexual orientation remain unanswered, and research on sexual orientation related neurobiological characteristics is still very limited. To contribute to a better understanding of the neurobiology of sexual orientation, we used magnetic resonance imaging (MRI in order to compare regional cortical thickness (Cth and subcortical volumes of homosexual men (hoM, heterosexual men (heM and heterosexual women (heW. hoM (and heW had thinner cortices primarily in visual areas and smaller thalamus volumes than heM, in which hoM and heW did not differ. Our results support previous studies, which suggest cerebral differences between hoM and heM in regions, where sex differences have been reported, which are frequently proposed to underlie biological mechanisms. Thus, our results contribute to a better understanding of the neurobiology of sexual orientation.

  5. Sexual orientation related differences in cortical thickness in male individuals.

    Science.gov (United States)

    Abé, Christoph; Johansson, Emilia; Allzén, Elin; Savic, Ivanka

    2014-01-01

    Previous neuroimaging studies demonstrated sex and also sexual orientation related structural and functional differences in the human brain. Genetic information and effects of sex hormones are assumed to contribute to the male/female differentiation of the brain, and similar effects could play a role in processes influencing human's sexual orientation. However, questions about the origin and development of a person's sexual orientation remain unanswered, and research on sexual orientation related neurobiological characteristics is still very limited. To contribute to a better understanding of the neurobiology of sexual orientation, we used magnetic resonance imaging (MRI) in order to compare regional cortical thickness (Cth) and subcortical volumes of homosexual men (hoM), heterosexual men (heM) and heterosexual women (heW). hoM (and heW) had thinner cortices primarily in visual areas and smaller thalamus volumes than heM, in which hoM and heW did not differ. Our results support previous studies, which suggest cerebral differences between hoM and heM in regions, where sex differences have been reported, which are frequently proposed to underlie biological mechanisms. Thus, our results contribute to a better understanding of the neurobiology of sexual orientation.

  6. Environmental Correlates of Individual Differences in Language Acquisition.

    Science.gov (United States)

    Furrow, David; Nelson, Katherine

    1984-01-01

    Reports on a study of mothers' uses of nouns and pronouns and their references to objects and persons as environmental variables which might relate to children's nominal preferences. Findings suggest that environmental factors do contribute to stylistic differences in language acquisition and that the communicative functions of language are an…

  7. The decision making individual differences inventory and guidelines for the study of individual differences in judgment and decision-making research

    NARCIS (Netherlands)

    Appelt, K.C.; Milch, K.F.; Handgraaf, M.J.J.; Weber, E.U.

    2011-01-01

    Individual differences in decision making are a topic of longstanding interest, but often yield inconsistent and contradictory results. After providing an overview of individual difference measures that have commonly been used in judgment and decision-making (JDM) research, we suggest that our

  8. Individual differences in strategic flight management and scheduling

    Science.gov (United States)

    Wickens, Christopher D.; Raby, Mireille

    1991-01-01

    A group of 30 instrument-rated pilots was made to fly simulator approaches to three airports under conditions of low, medium, and high workload conditions. An analysis is presently conducted of the difference in discrete task scheduling between the group of 10 highest and 10 lowest performing pilots in the sample; this categorization was based on the mean of various flight-profile measures. The two groups were found to differ from each other only in terms of the time when specific events were conducted, and of the optimality of scheduling for certain high-priority tasks. These results are assessed in view of the relative independence of task-management skills from aircraft-control skills.

  9. Individualism in plant populations: using stochastic differential equations to model individual neighbourhood-dependent plant growth.

    Science.gov (United States)

    Lv, Qiming; Schneider, Manuel K; Pitchford, Jonathan W

    2008-08-01

    We study individual plant growth and size hierarchy formation in an experimental population of Arabidopsis thaliana, within an integrated analysis that explicitly accounts for size-dependent growth, size- and space-dependent competition, and environmental stochasticity. It is shown that a Gompertz-type stochastic differential equation (SDE) model, involving asymmetric competition kernels and a stochastic term which decreases with the logarithm of plant weight, efficiently describes individual plant growth, competition, and variability in the studied population. The model is evaluated within a Bayesian framework and compared to its deterministic counterpart, and to several simplified stochastic models, using distributional validation. We show that stochasticity is an important determinant of size hierarchy and that SDE models outperform the deterministic model if and only if structural components of competition (asymmetry; size- and space-dependence) are accounted for. Implications of these results are discussed in the context of plant ecology and in more general modelling situations.

  10. Gender-related differences in individuals seeking treatment for kleptomania.

    Science.gov (United States)

    Grant, Jon E; Potenza, Marc N

    2008-03-01

    Understanding variations in disease presentation in men and women is clinically important as differences may reflect biological and sociocultural factors and have implications for prevention and treatment strategies. Few empirical investigations have been performed in kleptomania, particularly with respect to gender-related influences. From 2001--2007, 95 adult subjects (n=27 [28.4%] males) with Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition-defined kleptomania were assessed on sociodemographics and clinical characteristics, including symptom severity, comorbidity, and functional impairment, to identify gender-related differences. Men and women showed substantial symptom severity and functional impairment. Compared with affected men, women with kleptomania were more likely to be married (47.1% vs 25.9%; P=.039), have a later age at shoplifting onset (20.9 vs 14 years of age; P=.001), steal household items (PKleptomania is similarly associated with significant impairment in women and men. Gender-related differences in clinical features and co-occurring disorders suggest that prevention and treatment strategies incorporate gender considerations.

  11. Differences between individual and societal health state valuations: any link with personality?

    Science.gov (United States)

    Chapman, Benjamin P; Franks, Peter; Duberstein, Paul R; Jerant, Anthony

    2009-08-01

    The concept of "adaptation" has been proposed to account for differences between individual and societal valuations of specific health states in patients with chronic diseases. Little is known about psychological indices of adaptational capacity, which may predict differences in individual and societal valuations of health states. We investigated whether such differences were partially explained by personality traits in chronic disease patients. Analysis of baseline data of randomized controlled trial. Three hundred seventy patients with chronic disease. The NEO-five factor inventory measure of personality, EuroQoL-5D (EQ-5D) societal-based, and the EQ visual analogue scale individually-based measures of health valuation. Regression analyses modeled Dev, a measure of difference between the EQ-Visual Analogue Scale and EQ-5D, as a function of personality traits, sociodemographic factors, and chronic diseases. Individual valuations were significantly and clinically higher than societal valuations among patients in the second and third quartile of conscientiousness (Dev = 0.08, P = 0.01); among covariates, only depression (Dev = -0.04, P = 0.046) was also associated with Dev. Compared with societal valuations of a given health state, persons at higher quartiles of conscientiousness report less disutility associated with poor health. The effect is roughly twice that of some estimates of minimally important clinical differences on the EQ-5D and of depression. Although useful at the aggregate level, societal preference measures may systematically undervalue the health states of more conscientious individuals. Future work should examine the impact this has on individual patient outcome evaluation in clinical studies.

  12. Individual differences in children's materialism: the role of peer relations.

    Science.gov (United States)

    Banerjee, Robin; Dittmar, Helga

    2008-01-01

    Associations between materialism and peer relations are likely to exist in elementary school children but have not been studied previously. The first two studies introduce a new Perceived Peer Group Pressures (PPGP) Scale suitable for this age group, demonstrating that perceived pressure regarding peer culture (norms for behavioral, attitudinal, and material characteristics) can be reliably measured and that it is connected to children's responses to hypothetical peer pressure vignettes. Studies 3 and 4 evaluate the main theoretical model of associations between peer relations and materialism. Study 3 supports the hypothesis that peer rejection is related to higher perceived peer culture pressure, which in turn is associated with greater materialism. Study 4 confirms that the endorsement of social motives for materialism mediates the relationship between perceived peer pressure and materialism.

  13. Cognitive Abilities, Monitoring Confidence, and Control Thresholds Explain Individual Differences in Heuristics and Biases.

    Science.gov (United States)

    Jackson, Simon A; Kleitman, Sabina; Howie, Pauline; Stankov, Lazar

    2016-01-01

    In this paper, we investigate whether individual differences in performance on heuristic and biases tasks can be explained by cognitive abilities, monitoring confidence, and control thresholds. Current theories explain individual differences in these tasks by the ability to detect errors and override automatic but biased judgments, and deliberative cognitive abilities that help to construct the correct response. Here we retain cognitive abilities but disentangle error detection, proposing that lower monitoring confidence and higher control thresholds promote error checking. Participants ( N = 250) completed tasks assessing their fluid reasoning abilities, stable monitoring confidence levels, and the control threshold they impose on their decisions. They also completed seven typical heuristic and biases tasks such as the cognitive reflection test and Resistance to Framing. Using structural equation modeling, we found that individuals with higher reasoning abilities, lower monitoring confidence, and higher control threshold performed significantly and, at times, substantially better on the heuristic and biases tasks. Individuals with higher control thresholds also showed lower preferences for risky alternatives in a gambling task. Furthermore, residual correlations among the heuristic and biases tasks were reduced to null, indicating that cognitive abilities, monitoring confidence, and control thresholds accounted for their shared variance. Implications include the proposal that the capacity to detect errors does not differ between individuals. Rather, individuals might adopt varied strategies that promote error checking to different degrees, regardless of whether they have made a mistake or not. The results support growing evidence that decision-making involves cognitive abilities that construct actions and monitoring and control processes that manage their initiation.

  14. Cognitive abilities, monitoring, and control explain individual differences in heuristics and biases

    Directory of Open Access Journals (Sweden)

    Simon Anthony Jackson

    2016-10-01

    Full Text Available In this paper, we investigate whether individual differences in performance on heuristic and biases tasks can be explained by cognitive abilities, monitoring confidence and control thresholds. Current theories explain individual differences in these tasks by the ability to detect errors and override automatic but biased judgements, and deliberative cognitive abilities that help to construct the correct response. Here we retain cognitive abilities but disentangle error detection, proposing that lower monitoring confidence and higher control thresholds promote error checking. Participants (N = 250 completed tasks assessing their fluid reasoning abilities, stable monitoring confidence levels, and the control threshold they impose on their decisions. They also completed seven typical heuristic and biases tasks such as the cognitive reflection test and resistance to framing. Using structural equation modelling, we found that individuals with higher reasoning abilities, lower monitoring confidence and higher control threshold performed significantly and, at times, substantially better on the heuristic and biases tasks. Individuals with higher control thresholds also showed lower preferences for risky alternatives in a gambling task. Furthermore, residual correlations among the heuristic and biases tasks were reduced to null, indicating that cognitive abilities, monitoring confidence and control thresholds accounted for their shared variance. Implications include the proposal that the capacity to detect errors does not differ between individuals. Rather, individuals might adopt varied strategies that promote error checking to different degrees, regardless of whether they have made a mistake or not. The results support growing evidence that decision making involves cognitive abilities that construct actions and monitoring and control processes that manage their initiation.

  15. A model for individual egg production in chickens

    NARCIS (Netherlands)

    Grossman, M.; Koops, W.J.

    2001-01-01

    Our primary objective was to improve on an existing model for the individual weekly egg production curve by modeling the curve as a sum of logistic functions: one for the increasing phase of production and a sum for the decreasing phases. To illustrate the model, we used four data sets from two

  16. Individual differences in impulsivity predict anticipatory eye movements.

    Directory of Open Access Journals (Sweden)

    Laetitia Cirilli

    Full Text Available Impulsivity is the tendency to act without forethought. It is a personality trait commonly used in the diagnosis of many psychiatric diseases. In clinical practice, impulsivity is estimated using written questionnaires. However, answers to questions might be subject to personal biases and misinterpretations. In order to alleviate this problem, eye movements could be used to study differences in decision processes related to impulsivity. Therefore, we investigated correlations between impulsivity scores obtained with a questionnaire in healthy subjects and characteristics of their anticipatory eye movements in a simple smooth pursuit task. Healthy subjects were asked to answer the UPPS questionnaire (Urgency Premeditation Perseverance and Sensation seeking Impulsive Behavior scale, which distinguishes four independent dimensions of impulsivity: Urgency, lack of Premeditation, lack of Perseverance, and Sensation seeking. The same subjects took part in an oculomotor task that consisted of pursuing a target that moved in a predictable direction. This task reliably evoked anticipatory saccades and smooth eye movements. We found that eye movement characteristics such as latency and velocity were significantly correlated with UPPS scores. The specific correlations between distinct UPPS factors and oculomotor anticipation parameters support the validity of the UPPS construct and corroborate neurobiological explanations for impulsivity. We suggest that the oculomotor approach of impulsivity put forth in the present study could help bridge the gap between psychiatry and physiology.

  17. Individualized Next-Generation Biomathematical Modeling of Fatigue and Performance

    National Research Council Canada - National Science Library

    Van Dongen, Hans P

    2006-01-01

    .... This project employed a cutting-edge technique called Bayesian forecasting to develop a novel biomathematical performance model to predict responses to sleep loss and circadian displacement for individual subjects...

  18. Individual differences in political ideology are effects of adaptive error management.

    Science.gov (United States)

    Petersen, Michael Bang; Aarøe, Lene

    2014-06-01

    We apply error management theory to the analysis of individual differences in the negativity bias and political ideology. Using principles from evolutionary psychology, we propose a coherent theoretical framework for understanding (1) why individuals differ in their political ideology and (2) the conditions under which these individual differences influence and fail to influence the political choices people make.

  19. Speed and lateral inhibition of stimulus processing contribute to individual differences in Stroop-task performance

    Directory of Open Access Journals (Sweden)

    Marnix eNaber

    2016-06-01

    Full Text Available The Stroop task is a popular neuropsychological test that measures executive control. Strong Stroop interference is commonly interpreted in neuropsychology as a diagnostic marker of an impairment in executive control, possibly reflecting executive dysfunction. However, popular models of the Stroop task indicate that several other aspects of colour and word processing may also account for individual differences in the Stroop task, independent of executive control. Here we use new approaches to investigate the degree to which individual differences in Stroop interference correlate with the relative processing speed of word and colour stimuli, and the lateral inhibition between visual stimuli. We conducted an electrophysiological and behavioural experiment to measure (1 how quickly an individual’s brain processes words and colours presented in isolation (P3 latency, and (2 the strength of an individual’s lateral inhibition between visual representations with a visual illusion. Both measures explained at least 40% of the variance in Stroop interference across individuals. As these measures were obtained in contexts not requiring any executive control, we conclude that the Stroop effect also measures an individual’s pre-set way of processing visual features such as words and colours. This study highlights the important contributions of stimulus processing speed and lateral inhibition to individual differences in Stroop interference, and challenges the general view that the Stroop task primarily assesses executive control.

  20. Modelling of individual subject ozone exposure response kinetics.

    Science.gov (United States)

    Schelegle, Edward S; Adams, William C; Walby, William F; Marion, M Susan

    2012-06-01

    A better understanding of individual subject ozone (O(3)) exposure response kinetics will provide insight into how to improve models used in the risk assessment of ambient ozone exposure. To develop a simple two compartment exposure-response model that describes individual subject decrements in forced expiratory volume in one second (FEV(1)) induced by the acute inhalation of O(3) lasting up to 8 h. FEV(1) measurements of 220 subjects who participated in 14 previously completed studies were fit to the model using both particle swarm and nonlinear least squares optimization techniques to identify three subject-specific coefficients producing minimum "global" and local errors, respectively. Observed and predicted decrements in FEV(1) of the 220 subjects were used for validation of the model. Further validation was provided by comparing the observed O(3)-induced FEV(1) decrements in an additional eight studies with predicted values obtained using model coefficients estimated from the 220 subjects used in cross validation. Overall the individual subject measured and modeled FEV(1) decrements were highly correlated (mean R(2) of 0.69 ± 0.24). In addition, it was shown that a matrix of individual subject model coefficients can be used to predict the mean and variance of group decrements in FEV(1). This modeling approach provides insight into individual subject O(3) exposure response kinetics and provides a potential starting point for improving the risk assessment of environmental O(3) exposure.

  1. Correlates of individual, and age-related, differences in short-term learning.

    Science.gov (United States)

    Zhang, Zhiyong; Davis, Hasker P; Salthouse, Timothy A; Tucker-Drob, Elliot M

    2007-07-01

    Latent growth models were applied to data on multitrial verbal and spatial learning tasks from two independent studies. Although significant individual differences in both initial level of performance and subsequent learning were found in both tasks, age differences were found only in mean initial level, and not in mean learning. In neither task was fluid or crystallized intelligence associated with learning. Although there were moderate correlations among the level parameters across the verbal and spatial tasks, the learning parameters were not significantly correlated with one another across task modalities. These results are inconsistent with the existence of a general (e.g., material-independent) learning ability.

  2. Age-Related Differences of Individuals' Arithmetic Strategy Utilization with Different Level of Math Anxiety.

    Science.gov (United States)

    Si, Jiwei; Li, Hongxia; Sun, Yan; Xu, Yanli; Sun, Yu

    2016-01-01

    The present study used the choice/no-choice method to investigate the effect of math anxiety on the strategy used in computational estimation and mental arithmetic tasks and to examine age-related differences in this regard. Fifty-seven fourth graders, 56 sixth graders, and 60 adults were randomly selected to participate in the experiment. Results showed the following: (1) High-anxious individuals were more likely to use a rounding-down strategy in the computational estimation task under the best-choice condition. Additionally, sixth-grade students and adults performed faster than fourth-grade students on the strategy execution parameter. Math anxiety affected response times (RTs) and the accuracy with which strategies were executed. (2) The execution of the partial-decomposition strategy was superior to that of the full-decomposition strategy on the mental arithmetic task. Low-math-anxious persons provided more accurate answers than did high-math-anxious participants under the no-choice condition. This difference was significant for sixth graders. With regard to the strategy selection parameter, the RTs for strategy selection varied with age.

  3. A Network-Individual-Resource Model for HIV Prevention

    Science.gov (United States)

    Johnson, Blair T.; Redding, Colleen A.; DiClemente, Ralph J.; Mustanski, Brian S.; Dodge, Brian M.; Sheeran, Paschal; Warren, Michelle R.; Zimmerman, Rick S.; Fisher, William A.; Conner, Mark T.; Carey, Michael P.; Fisher, Jeffrey D.; Stall, Ronald D.; Fishbein, Martin

    2014-01-01

    HIV is transmitted through dyadic exchanges of individuals linked in transitory or permanent networks of varying sizes. To optimize prevention efficacy, a complementary theoretical perspective that bridges key individual level elements with important network elements can be a foundation for developing and implementing HIV interventions with outcomes that are more sustainable over time and have greater dissemination potential. Toward that end, we introduce a Network-Individual-Resource (NIR) model for HIV prevention that recognizes how exchanges of resources between individuals and their networks underlies and sustains HIV-risk behaviors. Individual behavior change for HIV prevention, then, may be dependent on increasing the supportiveness of that individual's relevant networks for such change. Among other implications, an NIR model predicts that the success of prevention efforts depends on whether the prevention efforts (1) prompt behavior changes that can be sustained by the resources the individual or their networks possess; (2) meet individual and network needs and are consistent with the individual's current situation/developmental stage; (3) are trusted and valued; and (4) target high HIV-prevalence networks. PMID:20862606

  4. Performance of different radiotherapy workload models

    International Nuclear Information System (INIS)

    Barbera, Lisa; Jackson, Lynda D.; Schulze, Karleen; Groome, Patti A.; Foroudi, Farshad; Delaney, Geoff P.; Mackillop, William J.

    2003-01-01

    Purpose: The purpose of this study was to evaluate the performance of different radiotherapy workload models using a prospectively collected dataset of patient and treatment information from a single center. Methods and Materials: Information about all individual radiotherapy treatments was collected for 2 weeks from the three linear accelerators (linacs) in our department. This information included diagnosis code, treatment site, treatment unit, treatment time, fields per fraction, technique, beam type, blocks, wedges, junctions, port films, and Eastern Cooperative Oncology Group (ECOG) performance status. We evaluated the accuracy and precision of the original and revised basic treatment equivalent (BTE) model, the simple and complex Addenbrooke models, the equivalent simple treatment visit (ESTV) model, fields per hour, and two local standards of workload measurement. Results: Data were collected for 2 weeks in June 2001. During this time, 151 patients were treated with 857 fractions. The revised BTE model performed better than the other models with a mean vertical bar observed - predicted vertical bar of 2.62 (2.44-2.80). It estimated 88.0% of treatment times within 5 min, which is similar to the previously reported accuracy of the model. Conclusion: The revised BTE model had similar accuracy and precision for data collected in our center as it did for the original dataset and performed the best of the models assessed. This model would have uses for patient scheduling, and describing workloads and case complexity

  5. Case management: a randomized controlled study comparing a neighborhood team and a centralized individual model.

    OpenAIRE

    Eggert, G M; Zimmer, J G; Hall, W J; Friedman, B

    1991-01-01

    This randomized controlled study compared two types of case management for skilled nursing level patients living at home: the centralized individual model and the neighborhood team model. The team model differed from the individual model in that team case managers performed client assessments, care planning, some direct services, and reassessments; they also had much smaller caseloads and were assigned a specific catchment area. While patients in both groups incurred very high estimated healt...

  6. Individual based and mean-field modeling of direct aggregation

    KAUST Repository

    Burger, Martin

    2013-10-01

    We introduce two models of biological aggregation, based on randomly moving particles with individual stochasticity depending on the perceived average population density in their neighborhood. In the firstorder model the location of each individual is subject to a density-dependent random walk, while in the second-order model the density-dependent random walk acts on the velocity variable, together with a density-dependent damping term. The main novelty of our models is that we do not assume any explicit aggregative force acting on the individuals; instead, aggregation is obtained exclusively by reducing the individual stochasticity in response to higher perceived density. We formally derive the corresponding mean-field limits, leading to nonlocal degenerate diffusions. Then, we carry out the mathematical analysis of the first-order model, in particular, we prove the existence of weak solutions and show that it allows for measure-valued steady states. We also perform linear stability analysis and identify conditions for pattern formation. Moreover, we discuss the role of the nonlocality for well-posedness of the first-order model. Finally, we present results of numerical simulations for both the first- and second-order model on the individual-based and continuum levels of description. 2012 Elsevier B.V. All rights reserved.

  7. Individual based and mean-field modeling of direct aggregation

    KAUST Repository

    Burger, Martin; Haskovec, Jan; Wolfram, Marie-Therese

    2013-01-01

    We introduce two models of biological aggregation, based on randomly moving particles with individual stochasticity depending on the perceived average population density in their neighborhood. In the firstorder model the location of each individual is subject to a density-dependent random walk, while in the second-order model the density-dependent random walk acts on the velocity variable, together with a density-dependent damping term. The main novelty of our models is that we do not assume any explicit aggregative force acting on the individuals; instead, aggregation is obtained exclusively by reducing the individual stochasticity in response to higher perceived density. We formally derive the corresponding mean-field limits, leading to nonlocal degenerate diffusions. Then, we carry out the mathematical analysis of the first-order model, in particular, we prove the existence of weak solutions and show that it allows for measure-valued steady states. We also perform linear stability analysis and identify conditions for pattern formation. Moreover, we discuss the role of the nonlocality for well-posedness of the first-order model. Finally, we present results of numerical simulations for both the first- and second-order model on the individual-based and continuum levels of description. 2012 Elsevier B.V. All rights reserved.

  8. Hybrid Modelling of Individual Movement and Collective Behaviour

    KAUST Repository

    Franz, Benjamin

    2013-01-01

    Mathematical models of dispersal in biological systems are often written in terms of partial differential equations (PDEs) which describe the time evolution of population-level variables (concentrations, densities). A more detailed modelling approach is given by individual-based (agent-based) models which describe the behaviour of each organism. In recent years, an intermediate modelling methodology - hybrid modelling - has been applied to a number of biological systems. These hybrid models couple an individual-based description of cells/animals with a PDE-model of their environment. In this chapter, we overview hybrid models in the literature with the focus on the mathematical challenges of this modelling approach. The detailed analysis is presented using the example of chemotaxis, where cells move according to extracellular chemicals that can be altered by the cells themselves. In this case, individual-based models of cells are coupled with PDEs for extracellular chemical signals. Travelling waves in these hybrid models are investigated. In particular, we show that in contrary to the PDEs, hybrid chemotaxis models only develop a transient travelling wave. © 2013 Springer-Verlag Berlin Heidelberg.

  9. Individual differences in the propensity to approach signals vs goals promote different adaptations in the dopamine system of rats.

    Science.gov (United States)

    Flagel, Shelly B; Watson, Stanley J; Robinson, Terry E; Akil, Huda

    2007-04-01

    The way an individual responds to cues associated with rewards may be a key determinant of vulnerability to compulsive behavioral disorders. We studied individual differences in Pavlovian conditioned approach behavior and examined the expression of neurobiological markers associated with the dopaminergic system, the same neural system implicated in incentive motivational processes. Pavlovian autoshaping procedures consisted of the brief presentation of an illuminated retractable lever (conditioned stimulus) followed by the response-independent delivery of a food pellet (unconditioned stimulus), which lead to a Pavlovian conditioned response. In situ hybridization was performed on brains obtained either following the first or last (fifth) day of training. Two phenotypes emerged. Sign-trackers (ST) exhibited behavior that seemed to be largely controlled by the cue that signaled impending reward delivery; whereas goal-trackers (GT) preferentially approached the location where the reward was delivered. Following a single training session, ST showed greater expression of dopamine D1 receptor mRNA relative to GT. After 5 days of training, GT exhibited greater expression levels of tyrosine hydroxylase, dopamine transporter, and dopamine D2 receptor mRNA relative to ST. These findings suggest that the development of approach behavior towards signals vs goal leads to distinct adaptations in the dopamine system. The sign-tracker vs goal-tracker phenotype may prove to be a valuable animal model to investigate individual differences in the way incentive salience is attributed to environmental stimuli, which may contribute to the development of addiction and other compulsive behavioral disorders.

  10. The role of test-retest reliability in measuring individual and group differences in executive functioning.

    Science.gov (United States)

    Paap, Kenneth R; Sawi, Oliver

    2016-12-01

    Studies testing for individual or group differences in executive functioning can be compromised by unknown test-retest reliability. Test-retest reliabilities across an interval of about one week were obtained from performance in the antisaccade, flanker, Simon, and color-shape switching tasks. There is a general trade-off between the greater reliability of single mean RT measures, and the greater process purity of measures based on contrasts between mean RTs in two conditions. The individual differences in RT model recently developed by Miller and Ulrich was used to evaluate the trade-off. Test-retest reliability was statistically significant for 11 of the 12 measures, but was of moderate size, at best, for the difference scores. The test-retest reliabilities for the Simon and flanker interference scores were lower than those for switching costs. Standard practice evaluates the reliability of executive-functioning measures using split-half methods based on data obtained in a single day. Our test-retest measures of reliability are lower, especially for difference scores. These reliability measures must also take into account possible day effects that classical test theory assumes do not occur. Measures based on single mean RTs tend to have acceptable levels of reliability and convergent validity, but are "impure" measures of specific executive functions. The individual differences in RT model shows that the impurity problem is worse than typically assumed. However, the "purer" measures based on difference scores have low convergent validity that is partly caused by deficiencies in test-retest reliability. Copyright © 2016 Elsevier B.V. All rights reserved.

  11. The emergence of leaders and followers in foraging pairs when the qualities of individuals differ

    Directory of Open Access Journals (Sweden)

    Cowlishaw Guy

    2008-02-01

    Full Text Available Abstract Background Foraging in groups offers animals a number of advantages, such as increasing their likelihood of finding food or detecting and avoiding predators. In order for a group to remain together, there has to be some degree of coordination of behaviour and movement between its members (which may in some cases be initiated by a decision-making leader, and in other cases may emerge as an underlying property of the group. For example, behavioural synchronisation is a phenomenon where animals within a group initiate and then continue to conduct identical behaviours, and has been characterised for a wide range of species. We examine how a pair of animals should behave using a state-dependent approach, and ask what conditions are likely to lead to behavioural synchronisation occurring, and whether one of the individuals is more likely to act as a leader. Results The model we describe considers how the energetic gain, metabolic requirements and predation risks faced by the individuals affect measures of their energetic state and behaviour (such as the degree of behavioural synchronisation seen within the pair, and the value to an individual of knowing the energetic state of its colleague. We explore how predictable changes in these measures are in response to changes in physiological requirements and predation risk. We also consider how these measures should change when the members of the pair are not identical in their metabolic requirements or their susceptibility to predation. We find that many of the changes seen in these measures are complex, especially when asymmetries exist between the members of the pair. Conclusion Analyses are presented that demonstrate that, although these general patterns are robust, care needs to be taken when considering the effects of individual differences, as the relationship between individual differences and the resulting qualitative changes in behaviour may be complex. We discuss how these results are

  12. Simulating individual-based models of epidemics in hierarchical networks

    NARCIS (Netherlands)

    Quax, R.; Bader, D.A.; Sloot, P.M.A.

    2009-01-01

    Current mathematical modeling methods for the spreading of infectious diseases are too simplified and do not scale well. We present the Simulator of Epidemic Evolution in Complex Networks (SEECN), an efficient simulator of detailed individual-based models by parameterizing separate dynamics

  13. Individual Learning Accounts and Other Models of Financing Lifelong Learning

    Science.gov (United States)

    Schuetze, Hans G.

    2007-01-01

    To answer the question "Financing what?" this article distinguishes several models of lifelong learning as well as a variety of lifelong learning activities. Several financing methods are briefly reviewed, however the principal focus is on Individual Learning Accounts (ILAs) which were seen by some analysts as a promising model for…

  14. Neural network configuration and efficiency underlies individual differences in spatial orientation ability.

    Science.gov (United States)

    Arnold, Aiden E G F; Protzner, Andrea B; Bray, Signe; Levy, Richard M; Iaria, Giuseppe

    2014-02-01

    Spatial orientation is a complex cognitive process requiring the integration of information processed in a distributed system of brain regions. Current models on the neural basis of spatial orientation are based primarily on the functional role of single brain regions, with limited understanding of how interaction among these brain regions relates to behavior. In this study, we investigated two sources of variability in the neural networks that support spatial orientation--network configuration and efficiency--and assessed whether variability in these topological properties relates to individual differences in orientation accuracy. Participants with higher accuracy were shown to express greater activity in the right supramarginal gyrus, the right precentral cortex, and the left hippocampus, over and above a core network engaged by the whole group. Additionally, high-performing individuals had increased levels of global efficiency within a resting-state network composed of brain regions engaged during orientation and increased levels of node centrality in the right supramarginal gyrus, the right primary motor cortex, and the left hippocampus. These results indicate that individual differences in the configuration of task-related networks and their efficiency measured at rest relate to the ability to spatially orient. Our findings advance systems neuroscience models of orientation and navigation by providing insight into the role of functional integration in shaping orientation behavior.

  15. Aging and Variability of Individual Differences: A Longitudinal Analysis of Social, Psychological, and Physiological Indicators.

    Science.gov (United States)

    Maddox, George L.; Douglass, Elizabeth B.

    This paper explores the relationship between age and individual differences. Two hypotheses were tested through the use of repeated measures of functioning in terms of social, psychological, and physiological parameters: (1) individual differences do not decrease with age, and (2) individuals tend to maintain the same rank in relation to age peers…

  16. Classification Systems for Individual Differences in Multiple-task Performance and Subjective Estimates of Workload

    Science.gov (United States)

    Damos, D. L.

    1984-01-01

    Human factors practitioners often are concerned with mental workload in multiple-task situations. Investigations of these situations have demonstrated repeatedly that individuals differ in their subjective estimates of workload. These differences may be attributed in part to individual differences in definitions of workload. However, after allowing for differences in the definition of workload, there are still unexplained individual differences in workload ratings. The relation between individual differences in multiple-task performance, subjective estimates of workload, information processing abilities, and the Type A personality trait were examined.

  17. Self-employed individuals performing different types of work have different occupational safety and health problems.

    Science.gov (United States)

    Park, Jungsun; Han, Boyoung; Kim, Yangho

    2018-05-22

    We assessed the occupational safety and health (OSH) issues of self-employed individuals in Korea. The working conditions and OSH issues in three groups were analyzed using the Korean Working Conditions Survey of 2014. Among self-employed individuals, "Physical work" was more common among males, whereas "Emotional work" was more common among females. Self-employed individuals performing "Mental work" had more education, higher incomes, and the lowest exposure to physical/chemical and ergonomic hazards in the workplace. In contrast, those performing "Physical work" were older, had less education, lower incomes, greater exposure to physical/chemical and ergonomic hazards in the workplace, and more health problems. Individuals performing "Physical work" were most vulnerable to OSH problems. The self-employed are a heterogeneous group of individuals. We suggest development of specific strategies that focus on workers performing "Physical work" to improve the health and safety of self-employed workers in Korea. © 2018 Wiley Periodicals, Inc.

  18. Individual Differences in Cognitive and Noncognitive Abilities and Team Performance in Dynamic Task Environments

    National Research Council Canada - National Science Library

    Doane, Stephanie

    2004-01-01

    The specific goal of this research was to examine the role of individual differences in cognitive and non-cognitive abilities on individual and team performance in a real-time dynamic team-task environment...

  19. Routine cognitive errors: a trait-like predictor of individual differences in anxiety and distress.

    Science.gov (United States)

    Fetterman, Adam K; Robinson, Michael D

    2011-02-01

    Five studies (N=361) sought to model a class of errors--namely, those in routine tasks--that several literatures have suggested may predispose individuals to higher levels of emotional distress. Individual differences in error frequency were assessed in choice reaction-time tasks of a routine cognitive type. In Study 1, it was found that tendencies toward error in such tasks exhibit trait-like stability over time. In Study 3, it was found that tendencies toward error exhibit trait-like consistency across different tasks. Higher error frequency, in turn, predicted higher levels of negative affect, general distress symptoms, displayed levels of negative emotion during an interview, and momentary experiences of negative emotion in daily life (Studies 2-5). In all cases, such predictive relations remained significant with individual differences in neuroticism controlled. The results thus converge on the idea that error frequency in simple cognitive tasks is a significant and consequential predictor of emotional distress in everyday life. The results are novel, but discussed within the context of the wider literatures that informed them. © 2010 Psychology Press, an imprint of the Taylor & Francis Group, an Informa business

  20. The Role of Affective and Cognitive Individual Differences in Social Perception.

    Science.gov (United States)

    Aquino, Antonio; Haddock, Geoffrey; Maio, Gregory R; Wolf, Lukas J; Alparone, Francesca R

    2016-06-01

    Three studies explored the connection between social perception processes and individual differences in the use of affective and cognitive information in relation to attitudes. Study 1 revealed that individuals high in need for affect (NFA) accentuated differences in evaluations of warm and cold traits, whereas individuals high in need for cognition (NFC) accentuated differences in evaluations of competent and incompetent traits. Study 2 revealed that individual differences in NFA predicted liking of warm or cold targets, whereas individual differences in NFC predicted perceptions of competent or incompetent targets. Furthermore, the effects of NFA and NFC were independent of structural bases and meta-bases of attitudes. Study 3 revealed that differences in the evaluation of warm and cold traits mediated the effects of NFA and NFC on liking of targets. The implications for social perception processes and for individual differences in affect-cognition are discussed. © 2016 by the Society for Personality and Social Psychology, Inc.

  1. Kinematic Differences During Single-Leg Step-Down Between Individuals With Femoroacetabular Impingement Syndrome and Individuals Without Hip Pain.

    Science.gov (United States)

    Lewis, Cara L; Loverro, Kari L; Khuu, Anne

    2018-04-01

    Study Design Controlled laboratory study, case-control design. Background Despite recognition that femoroacetabular impingement syndrome (FAIS) is a movement-related disorder, few studies have examined dynamic unilateral tasks in individuals with FAIS. Objectives To determine whether movements of the pelvis and lower extremities in individuals with FAIS differ from those in individuals without hip pain during a single-leg step-down, and to analyze kinematic differences between male and female participants within groups. Methods Individuals with FAIS and individuals without hip pain performed a single-leg step-down while kinematic data were collected. Kinematics were evaluated at 60° of knee flexion. A linear regression analysis assessed the main effects of group, sex, and side, and the interaction of sex by group. Results Twenty individuals with FAIS and 40 individuals without hip pain participated. Individuals with FAIS performed the step-down with greater hip flexion (4.9°; 95% confidence interval [CI]: 0.5°, 9.2°) and anterior pelvic tilt (4.1°; 95% CI: 0.9°, 7.3°) than individuals without hip pain. Across groups, female participants performed the task with more hip flexion (6.1°; 95% CI: 1.7°, 10.4°), hip adduction (4.8°; 95% CI: 2.2°, 7.4°), anterior pelvic tilt (5.8°; 95% CI: 2.6°, 9.0°), pelvic drop (1.4°; 95% CI: 0.3°, 2.5°), and thigh adduction (2.7°; 95% CI: 1.3°, 4.2°) than male participants. Conclusion The results of this study suggest that individuals with FAIS have alterations in pelvic motion during a dynamic unilateral task. The noted altered movement patterns in the FAIS group may contribute to the development of hip pain and may be due to impairments that are modifiable through rehabilitation. J Orthop Sports Phys Ther 2018;48(4):270-279. Epub 6 Mar 2018. doi:10.2519/jospt.2018.7794.

  2. Individual differences and day-to-day fluctuations in goal planning and type 1 diabetes management.

    Science.gov (United States)

    Wiebe, Deborah J; Baker, Ashley C; Suchy, Yana; Stump, Tammy K; Berg, Cynthia A

    2018-04-26

    To examine whether individual differences and day-to-day fluctuations in diabetes goal planning are associated with Type 1 diabetes (T1D) management during late adolescence, and whether lapses in daily diabetes goal planning are more disruptive to diabetes management among those with poorer executive functioning (EF). Late adolescents with T1D (N = 236, Mage = 17.77 years) completed survey measures assessing individual differences in levels of diabetes goal planning and adherence, as well as survey and performance-based measures of EF; glycemic control was assessed through glycated hemoglobin (HbA1c) assays. Participants then completed a 2-week daily diary, rating items measuring daily diabetes goal planning, goal effort, and adherence, and recording blood-glucose tests from their glucometer at the end of each day. Analyses of survey measures indicated that higher individual differences in diabetes goal planning were associated with better adherence and glycemic control. Analyses of daily data using hierarchical linear modeling indicated that adolescents displayed higher daily adherence and lower blood-glucose levels on days when they had higher-than-their-average levels of daily goal planning and daily goal effort. EF moderated the association between daily goal planning and daily adherence, indicating that lapses in daily goal planning were more disruptive for adolescents with poorer EF. Both individual differences and day-to-day fluctuations in diabetes goal planning are associated with diabetes management, highlighting the challenges of managing T1D in daily life. Youth in late adolescence with poorer EF may especially benefit from planning to attain diabetes goals on a daily basis. (PsycINFO Database Record (c) 2018 APA, all rights reserved).

  3. Individual differences in impression management: an exploration of the psychological processes underlying faking

    Directory of Open Access Journals (Sweden)

    ROSE A. MUELLER-HANSON

    2006-09-01

    Full Text Available The present study proposes and tests a model of psychological processes underlying faking, which integrates concepts from earlier models of faking by McFarland and Ryan (2000; 2001 and Snell, Sydell, and Lueke (1999. The results provided partial support for the model, suggesting personality factors and perceptions of situational factors contribute to faking behavior. The implications of these findings are (a people differ with regard to how much they will fake on a personality test in a simulated employment setting with some people faking substantially and others faking very little or not at all, and (b the extent to which an individual fakes is partially determined by the person’s attitudes and personality characteristics. The present findings are interpreted, discussed, and might be useful for the prevention and mitigation of faking by altering people's beliefs about their ability to fake and the appropriateness of faking.

  4. Cognitive control and individual differences in economic ultimatum decision-making.

    Directory of Open Access Journals (Sweden)

    Wim De Neys

    Full Text Available Much publicity has been given to the fact that people's economic decisions often deviate from the rational predictions of standard economic models. In the classic ultimatum game, for example, most people turn down financial gains by rejecting unequal monetary splits. The present study points to neglected individual differences in this debate. After participants played the ultimatum game we tested for individual differences in cognitive control capacity of the most and least economic responders. The key finding was that people who were higher in cognitive control, as measured by behavioral (Go/No-Go performance and neural (No-Go N2 amplitude markers, did tend to behave more in line with the standard models and showed increased acceptance of unequal splits. Hence, the cognitively highest scoring decision-makers were more likely to maximize their monetary payoffs and adhere to the standard economic predictions. Findings question popular claims with respect to the rejection of standard economic models and the irrationality of human economic decision-making.

  5. A Complex Story: Universal Preference vs. Individual Differences Shaping Aesthetic Response to Fractals Patterns

    Science.gov (United States)

    Street, Nichola; Forsythe, Alexandra M.; Reilly, Ronan; Taylor, Richard; Helmy, Mai S.

    2016-01-01

    Fractal patterns offer one way to represent the rough complexity of the natural world. Whilst they dominate many of our visual experiences in nature, little large-scale perceptual research has been done to explore how we respond aesthetically to these patterns. Previous research (Taylor et al., 2011) suggests that the fractal patterns with mid-range fractal dimensions (FDs) have universal aesthetic appeal. Perceptual and aesthetic responses to visual complexity have been more varied with findings suggesting both linear (Forsythe et al., 2011) and curvilinear (Berlyne, 1970) relationships. Individual differences have been found to account for many of the differences we see in aesthetic responses but some, such as culture, have received little attention within the fractal and complexity research fields. This two-study article aims to test preference responses to FD and visual complexity, using a large cohort (N = 443) of participants from around the world to allow universality claims to be tested. It explores the extent to which age, culture and gender can predict our preferences for fractally complex patterns. Following exploratory analysis that found strong correlations between FD and visual complexity, a series of linear mixed-effect models were implemented to explore if each of the individual variables could predict preference. The first tested a linear complexity model (likelihood of selecting the more complex image from the pair of images) and the second a mid-range FD model (likelihood of selecting an image within mid-range). Results show that individual differences can reliably predict preferences for complexity across culture, gender and age. However, in fitting with current findings the mid-range models show greater consistency in preference not mediated by gender, age or culture. This article supports the established theory that the mid-range fractal patterns appear to be a universal construct underlying preference but also highlights the fragility of

  6. Individual-based modelling and control of bovine brucellosis

    Science.gov (United States)

    Nepomuceno, Erivelton G.; Barbosa, Alípio M.; Silva, Marcos X.; Perc, Matjaž

    2018-05-01

    We present a theoretical approach to control bovine brucellosis. We have used individual-based modelling, which is a network-type alternative to compartmental models. Our model thus considers heterogeneous populations, and spatial aspects such as migration among herds and control actions described as pulse interventions are also easily implemented. We show that individual-based modelling reproduces the mean field behaviour of an equivalent compartmental model. Details of this process, as well as flowcharts, are provided to facilitate the reproduction of the presented results. We further investigate three numerical examples using real parameters of herds in the São Paulo state of Brazil, in scenarios which explore eradication, continuous and pulsed vaccination and meta-population effects. The obtained results are in good agreement with the expected behaviour of this disease, which ultimately showcases the effectiveness of our theory.

  7. Assimilation and Individual Differences in Emotion: The Dynamics of Anger and Approach Motivation.

    Science.gov (United States)

    Lechuga, Julia; Fernandez, Norma P

    2011-03-01

    Individuals who cross cultural boundaries face many challenges when trying to adapt to a receiving culture. Adaptation challenges such as learning to maneuver across societal domains may become increasingly complex if structural level factors such as discrimination are present. Researchers have conceptualized acculturation as a relatively autonomous decision indicating that four acculturation strategies exist: assimilation, separation, integration, and marginalization. Moreover, researchers have also long debated the link between acculturation strategy, adaptation hassles and negative health outcomes. However, models seeking to explain how individual difference and structural level variables may influence each other and subsequently influence acculturation and adaptation are needed. The purpose of this study is to lay the foundation for the conceptualization of such a model. We propose that temperamental predispositions to negative emotionality, anger, and impulsivity may highlight discrimination which in turn may lead to increases in acculturative stress and negative markers of psychosocial well-being. We used SEM to test our hypothesized model. Results supported a modified model. Implications for the measurement of adaptation and interventions are discussed.

  8. Conceptual Analysis and Implications of Students' Individual Differences to Curriculum Implementation in Technical Education

    Science.gov (United States)

    Akpan, Godwin A.; Essien, Emmanuel O.; Okure, Okure S.

    2013-01-01

    Individual differences refer to the unique ways each human being differs from another human being as expressed in behaviour or perceived in the physical appearance. Three factors of individual differences identified to be closely related to learning/acquisition of skills and performance of tasks. These are personality dimensions, self-efficacy and…

  9. Phonetic imitation from an individual-difference perspective: subjective attitude, personality and "autistic" traits.

    Science.gov (United States)

    Yu, Alan C L; Abrego-Collier, Carissa; Sonderegger, Morgan

    2013-01-01

    Numerous studies have documented the phenomenon of phonetic imitation: the process by which the production patterns of an individual become more similar on some phonetic or acoustic dimension to those of her interlocutor. Though social factors have been suggested as a motivator for imitation, few studies has established a tight connection between language-external factors and a speaker's likelihood to imitate. The present study investigated the phenomenon of phonetic imitation using a within-subject design embedded in an individual-differences framework. Participants were administered a phonetic imitation task, which included two speech production tasks separated by a perceptual learning task, and a battery of measures assessing traits associated with Autism-Spectrum Condition, working memory, and personality. To examine the effects of subjective attitude on phonetic imitation, participants were randomly assigned to four experimental conditions, where the perceived sexual orientation of the narrator (homosexual vs. heterosexual) and the outcome (positive vs. negative) of the story depicted in the exposure materials differed. The extent of phonetic imitation by an individual is significantly modulated by the story outcome, as well as by the participant's subjective attitude toward the model talker, the participant's personality trait of openness and the autistic-like trait associated with attention switching.

  10. Phonetic imitation from an individual-difference perspective: subjective attitude, personality and "autistic" traits.

    Directory of Open Access Journals (Sweden)

    Alan C L Yu

    Full Text Available Numerous studies have documented the phenomenon of phonetic imitation: the process by which the production patterns of an individual become more similar on some phonetic or acoustic dimension to those of her interlocutor. Though social factors have been suggested as a motivator for imitation, few studies has established a tight connection between language-external factors and a speaker's likelihood to imitate. The present study investigated the phenomenon of phonetic imitation using a within-subject design embedded in an individual-differences framework. Participants were administered a phonetic imitation task, which included two speech production tasks separated by a perceptual learning task, and a battery of measures assessing traits associated with Autism-Spectrum Condition, working memory, and personality. To examine the effects of subjective attitude on phonetic imitation, participants were randomly assigned to four experimental conditions, where the perceived sexual orientation of the narrator (homosexual vs. heterosexual and the outcome (positive vs. negative of the story depicted in the exposure materials differed. The extent of phonetic imitation by an individual is significantly modulated by the story outcome, as well as by the participant's subjective attitude toward the model talker, the participant's personality trait of openness and the autistic-like trait associated with attention switching.

  11. Phonetic Imitation from an Individual-Difference Perspective: Subjective Attitude, Personality and “Autistic” Traits

    Science.gov (United States)

    Yu, Alan C. L.; Abrego-Collier, Carissa; Sonderegger, Morgan

    2013-01-01

    Numerous studies have documented the phenomenon of phonetic imitation: the process by which the production patterns of an individual become more similar on some phonetic or acoustic dimension to those of her interlocutor. Though social factors have been suggested as a motivator for imitation, few studies has established a tight connection between language-external factors and a speaker’s likelihood to imitate. The present study investigated the phenomenon of phonetic imitation using a within-subject design embedded in an individual-differences framework. Participants were administered a phonetic imitation task, which included two speech production tasks separated by a perceptual learning task, and a battery of measures assessing traits associated with Autism-Spectrum Condition, working memory, and personality. To examine the effects of subjective attitude on phonetic imitation, participants were randomly assigned to four experimental conditions, where the perceived sexual orientation of the narrator (homosexual vs. heterosexual) and the outcome (positive vs. negative) of the story depicted in the exposure materials differed. The extent of phonetic imitation by an individual is significantly modulated by the story outcome, as well as by the participant’s subjective attitude toward the model talker, the participant’s personality trait of openness and the autistic-like trait associated with attention switching. PMID:24098665

  12. Canadian individual risks of radon-induced lung cancer for different exposure profiles.

    Science.gov (United States)

    Chen, Jing

    2005-01-01

    Indoor radon has been determined to be the second leading cause of lung cancer after tobacco smoking. There is an increasing need among radiation practitioners to have numerical values of lung cancer risks for men and women, ever-smokers and never-smokers exposed to radon in homes. This study evaluates individual risks for the Canadian population exposed to radon in homes at different radon concentrations and for different periods of their lives. Based on the risk model developed recently by U.S. Environmental Protection Agency (EPA), individual risks of radon-induced lung cancers are calculated with Canadian age-specific rates for overall and lung cancer mortalities (1996-2000) as well as the Canadian smoking prevalence data in 2002. Convenient tables of lifetime relative risks are constructed for lifetime exposures and short exposures between any two age intervals from 0 to 110, and for various radon concentrations found in homes from 50 to 1000 Bq/m3. The risk of developing lung cancer from residential radon exposure increases with radon concentration and exposure duration. For short exposure periods, such as 10 or 20 years, risks are higher in middle age groups (30-50) compared especially to the later years. Individuals could lower their risks significantly by reducing radon levels earlier in life. The tables could help radiation protection practitioners to better communicate indoor radon risk to members of the public.

  13. I can't wait: Methods for measuring and moderating individual differences in impulsive choice.

    Science.gov (United States)

    Peterson, Jennifer R; Hill, Catherine C; Marshall, Andrew T; Stuebing, Sarah L; Kirkpatrick, Kimberly

    2015-01-01

    Impulsive choice behavior occurs when individuals make choices without regard for future consequences. This behavior is often maladaptive and is a common symptom in many disorders, including drug abuse, compulsive gambling, and obesity. Several proposed mechanisms may influence impulsive choice behavior. These mechanisms provide a variety of pathways that may provide the basis for individual differences that are often evident when measuring choice behavior. This review provides an overview of these different pathways to impulsive choice, and the behavioral intervention strategies being developed to moderate impulsive choice. Because of the compelling link between impulsive choice behavior and the near-epidemic pervasiveness of obesity in the United States, we focus on the relationship between impulsive choice behavior and obesity as a test case for application of the multiple pathways approach. Choosing immediate gratification over healthier long term food choices is a contributing factor to the obesity crisis. Behavioral interventions can lead to more self controlled choices in a rat pre-clinical model, suggesting a possible gateway for translation to human populations. Designing and implementing effective impulsive choice interventions is crucial to improving the overall health and well-being of impulsive individuals.

  14. Explaining individual differences in alcohol intake in adults: evidence for genetic and cultural transmission?

    Science.gov (United States)

    van Beek, Jenny H D A; de Moor, Marleen H M; Geels, Lot M; Willemsen, Gonneke; Boomsma, Dorret I

    2014-03-01

    The current study aimed to describe what proportion of variation in adult alcohol intake is attributable to genetic differences among individuals and what proportion to differences in environmental experiences individuals have been exposed to. Effects of age, gender, spousal resemblance, and cultural transmission of alcohol intake from parents to offspring were taken into account. In a twin-family design, the effects of genetic and cultural transmission and shared and nonshared environment on alcohol intake were estimated with genetic structural equation models. Data originated from adult twins, their siblings, parents (n = 12,587), and spouses (n = 429) registered with the population-based Netherlands Twin Register (63.5% female; ages 18-97 years). Alcohol intake (grams per day) was higher among men than women and increased with age. Broad-sense heritability estimates were similar across sex and age (53%). Spousal resemblance was observed (r = .39) but did not significantly affect the heritability estimates. No effects of cultural transmission were detected. In total, 23% of the variation in alcohol intake was explained by additive genetic effects, 30% by dominant (nonadditive) gene action, and 47% by environmental effects that were not shared among family members. Individual differences in adult alcohol intake are explained by genetic and individual-specific environmental effects. The same genes are expressed in males and females and in younger and older participants. A substantial part of the heritability of alcohol intake is attributable to nonadditive gene action. Effects of cultural transmission that have been reported in adolescence are not present in adulthood.

  15. Exploring Individual Differences in Irregular Word Recognition among Children with Early-Emerging and Late-Emerging Word Reading Difficulty

    Science.gov (United States)

    Steacy, Laura M.; Kearns, Devin M.; Gilbert, Jennifer K.; Compton, Donald L.; Cho, Eunsoo; Lindstrom, Esther R.; Collins, Alyson A.

    2017-01-01

    Models of irregular word reading that take into account both child- and word-level predictors have not been evaluated in typically developing children and children with reading difficulty (RD). The purpose of the present study was to model individual differences in irregular word reading ability among 5th grade children (N = 170), oversampled for…

  16. Individual loss reserving with the Multivariate Skew Normal model

    NARCIS (Netherlands)

    Pigeon, M.; Antonio, K.; Denuit, M.

    2011-01-01

    In general insurance, the evaluation of future cash ows and solvency capital has become increasingly important. To assist in this process, the present paper proposes an individual discrete-time loss re- serving model describing the occurrence, the reporting delay, the timeto the first payment, and

  17. Modelling community, family, and individual determinants of childhood dental caries

    NARCIS (Netherlands)

    Duijster, D.; Loveren, C. van; Dusseldorp, E.; Verrips, G.H.W.

    2014-01-01

    This cross-sectional study empirically tested a theoretical model of pathways and inter-relationships among community, family, and individual determinants of childhood dental caries in a sample of 630, 6-year-old children from the Netherlands. Children's decayed, missing, and filled teeth (dmft)

  18. Individual based model of slug population and spatial dynamics

    NARCIS (Netherlands)

    Choi, Y.H.; Bohan, D.A.; Potting, R.P.J.; Semenov, M.A.; Glen, D.M.

    2006-01-01

    The slug, Deroceras reticulatum, is one of the most important pests of agricultural and horticultural crops in UK and Europe. In this paper, a spatially explicit individual based model (IbM) is developed to study the dynamics of a population of D. reticulatum. The IbM establishes a virtual field

  19. Sources of individual differences in depressive symptoms: analysis of two samples of twins and their families.

    Science.gov (United States)

    Kendler, K S; Walters, E E; Truett, K R; Heath, A C; Neale, M C; Martin, N G; Eaves, L J

    1994-11-01

    Self-reported symptoms of depression are commonly used in mental health research to assess current psychiatric state, yet wide variation in these symptoms among individuals has been found in both clinical and epidemiologic populations. The authors sought to understand, from a genetic-epidemiologic perspective, the sources of individual differences in depressive symptoms. Self-reported symptoms of depression were assessed in two samples of twins and their spouses, parents, siblings, and offspring: one sample contained volunteer twins recruited through the American Association of Retired Persons and their relatives (N = 19,203 individuals) and the other contained twins from a population-based twin registry in Virginia and their relatives (N = 11,242 individuals). Model fitting by an iterative, diagonal, weighted least squares method was applied to the 80 different family relationships in the extended twin-family design. Independent analyses of the two samples revealed that the level of depressive symptoms was modestly familial, and familial resemblance could be explained solely by genetic factors and spousal resemblance. The estimated heritability of depressive symptoms was between 30% and 37%. There was no evidence that the liability to depressive symptoms was environmentally transmitted from parents to offspring or was influenced by environmental factors shared either generally among siblings or specifically between twins. With correction for unreliability of measurement, genetic factors accounted for half of the stable variance in depressive symptoms. Depressive symptoms in adulthood partly reflect enduring characteristics of temperament that are substantially influenced by hereditary factors but little, or not at all, by shared environmental experiences in the family of origin.

  20. The contribution of attentional lapses to individual differences in visual working memory capacity.

    Science.gov (United States)

    Adam, Kirsten C S; Mance, Irida; Fukuda, Keisuke; Vogel, Edward K

    2015-08-01

    Attentional control and working memory capacity are important cognitive abilities that substantially vary between individuals. Although much is known about how attentional control and working memory capacity relate to each other and to constructs like fluid intelligence, little is known about how trial-by-trial fluctuations in attentional engagement impact trial-by-trial working memory performance. Here, we employ a novel whole-report memory task that allowed us to distinguish between varying levels of attentional engagement in humans performing a working memory task. By characterizing low-performance trials, we can distinguish between models in which working memory performance failures are caused by either (1) complete lapses of attention or (2) variations in attentional control. We found that performance failures increase with set-size and strongly predict working memory capacity. Performance variability was best modeled by an attentional control model of attention, not a lapse model. We examined neural signatures of performance failures by measuring EEG activity while participants performed the whole-report task. The number of items correctly recalled in the memory task was predicted by frontal theta power, with decreased frontal theta power associated with poor performance on the task. In addition, we found that poor performance was not explained by failures of sensory encoding; the P1/N1 response and ocular artifact rates were equivalent for high- and low-performance trials. In all, we propose that attentional lapses alone cannot explain individual differences in working memory performance. Instead, we find that graded fluctuations in attentional control better explain the trial-by-trial differences in working memory that we observe.

  1. Strategic Adaptation to Task Characteristics, Incentives, and Individual Differences in Dual-Tasking.

    Directory of Open Access Journals (Sweden)

    Christian P Janssen

    Full Text Available We investigate how good people are at multitasking by comparing behavior to a prediction of the optimal strategy for dividing attention between two concurrent tasks. In our experiment, 24 participants had to interleave entering digits on a keyboard with controlling a randomly moving cursor with a joystick. The difficulty of the tracking task was systematically varied as a within-subjects factor. Participants were also exposed to different explicit reward functions that varied the relative importance of the tracking task relative to the typing task (between-subjects. Results demonstrate that these changes in task characteristics and monetary incentives, together with individual differences in typing ability, influenced how participants choose to interleave tasks. This change in strategy then affected their performance on each task. A computational cognitive model was used to predict performance for a wide set of alternative strategies for how participants might have possibly interleaved tasks. This allowed for predictions of optimal performance to be derived, given the constraints placed on performance by the task and cognition. A comparison of human behavior with the predicted optimal strategy shows that participants behaved near optimally. Our findings have implications for the design and evaluation of technology for multitasking situations, as consideration should be given to the characteristics of the task, but also to how different users might use technology depending on their individual characteristics and their priorities.

  2. Individual Differences in Numeracy and Cognitive Reflection, with Implications for Biases and Fallacies in Probability Judgment

    NARCIS (Netherlands)

    J.M. Liberali (Jordana ); V.F. Reyna (Valerie ); S. Furlan (Sarah); L.M. Stein (Lilian ); S.T. Pardo (Seth )

    2012-01-01

    textabstractDespite evidence that individual differences in numeracy affect judgment and decision making, the precise mechanisms underlying how such differences produce biases and fallacies remain unclear. Numeracy scales have been developed without sufficient theoretical grounding, and their

  3. Individual differences in dispositional mindfulness and brain activity involved in reappraisal of emotion

    NARCIS (Netherlands)

    Modinos, Gemma; Ormel, Johan; Aleman, Andre

    2010-01-01

    The regulation of negative emotion through reappraisal has been shown to induce increased prefrontal activity and decreased amygdala activity. Individual differences in dispositional mindfulness reflect differences in typical recognition, detachment and regulation of current experience, thought to

  4. Individual differences in approach motivation, resting-state frontal cortical activity and attentional scope

    NARCIS (Netherlands)

    Boksem, M.A.S.; Kostermans, E.; Tops, M.; de Cremer, D.

    2012-01-01

    Recent research has demonstrated that individual differences in approach motivation modulate attentional scope. In turn, approach and inhibition have been related to different neural systems that are associated with asymmetries in relative frontal activity (RFA). Here, we investigated whether such

  5. Therapeutic Enactment: Integrating Individual and Group Counseling Models for Change

    Science.gov (United States)

    Westwood, Marvin J.; Keats, Patrice A.; Wilensky, Patricia

    2003-01-01

    The purpose of this article is to introduce the reader to a group-based therapy model known as therapeutic enactment. A description of this multimodal change model is provided by outlining the relevant background information, key concepts related to specific change processes, and the differences in this model compared to earlier psychodrama…

  6. Individual Differences in the Processing of Written Sarcasm and Metaphor: Evidence from Eye Movements

    Science.gov (United States)

    Olkoniemi, Henri; Ranta, Henri; Kaakinen, Johanna K.

    2016-01-01

    The present study examined individual differences in the processing of different forms of figurative language. Sixty participants read sarcastic, metaphorical, and literal sentences embedded in story contexts while their eye movements were recorded, and responded to a text memory and an inference question after each story. Individual differences…

  7. Individual Differences in Kindergarten Math Achievement: The Integrative Roles of Approximation Skills and Working Memory

    NARCIS (Netherlands)

    Xenidou-Dervou, I.; De Smedt, B.; van der Schoot, M.; van Lieshout, E.C.D.M.

    2013-01-01

    Kindergarteners can conduct basic computations with large nonsymbolic (e.g. dots, objects) and symbolic (i.e. Arabic numbers) numerosities in an approximate manner. These abilities are related to individual differences in mathematics achievement. At the same time, these individual differences are

  8. Identifying the Individual Differences among Students during Learning and Teaching Process by Science Teachers

    Science.gov (United States)

    Kubat, Ulas

    2018-01-01

    It is important for teachers to know variables such as physical characteristics, intelligence, perception, gender, ability, learning styles, which are individual differences of the learners. An effective and productive learning-teaching process can be planned by considering these individual differences of the students. Since the learners' own…

  9. Individual Subjective Initiative Merge Model Based on Cellular Automaton

    Directory of Open Access Journals (Sweden)

    Yin-Jie Xu

    2013-01-01

    Full Text Available The merge control models proposed for work zones are classified into two types (Hard Control Merge (HCM model and Soft Control Merge (SCM model according to their own control intensity and are compared with a new model, called Individual Subjective Initiative Merge (ISIM model, which is based on the linear lane-changing probability strategy in the merging area. The attention of this paper is paid to the positive impact of the individual subjective initiative for the whole traffic system. Three models (ISIM, HCM, and SCM are established and compared with each other by two order parameters, that is, system output and average vehicle travel time. Finally, numerical results show that both ISIM and SCM perform better than HCM. Compared with SCM, the output of ISIM is 20 vehicles per hour higher under the symmetric input condition and is more stable under the asymmetric input condition. Meanwhile, the average travel time of ISIM is 2000 time steps less under the oversaturated input condition.

  10. P2-17: Individual Differences in Dynamic Criterion Shifts during Perceptual Decision Making

    Directory of Open Access Journals (Sweden)

    Issac Rhim

    2012-10-01

    Full Text Available Perceptual decision-making involves placing an optimal criterion on the axis of encoded sensory evidence to maximize outcomes for choices. Optimal criterion setting becomes critical particularly when neural representations of sensory inputs are noisy and feedbacks for perceptual choices vary over time in an unpredictable manner. Here we monitored time courses of decision criteria that are adopted by human subjects while abruptly shifting the criterion of stochastic feedback to perceptual choices with certain amounts in an unpredictable direction and at an unpredictable point of time. Subjects viewed a brief (0.3 s, thin (.07 deg annulus around the fixation and were forced to judge whether the annulus was smaller or larger than an unknown boundary. We estimated moment-to-moment criteria by fitting a cumulative Gaussian function to the data within a sliding window of trials that are locked to a shift in feedback criterion. Unpredictable shifts in feedback criterion successfully induced shifts in actual decision criterion towards an optimal criterion for many of subjects, but with time delay and amount of shifts varying across individual subjects. There were disproportionately more numbers of overshooters (reaching and then surpassing the optimal criterion required than undershooters (subpar reach, with a significant anti-correlation with sensory sensitivity. To find a mechanism that generates these individual differences, we developed a dynamic criterion learning model by modifying a reinforcement learning model, which assumes that a criterion is adjusted every trial by a weighted discrepancy between actual and expected rewards.

  11. Cross-national differences in women's repartnering behaviour in Europe: The role of individual demographic characteristics

    Directory of Open Access Journals (Sweden)

    Paulina Gałęzewska

    2017-07-01

    Full Text Available Background: With rising union instability across Europe, more individuals now re-enter the partner market and eventually repartner. The increase in cohabitation may also be influencing repartnering behaviour. While several studies examine individual-level characteristics related to repartnering, few take a broader view and compare repartnering levels or explore how demographic characteristics associated with repartnering differ across Europe. Objective: We describe levels of repartnering and the characteristics of those exposed to repartnering in 11 European countries. We then examine whether the relationship between women's demographic characteristics at union dissolution and repartnering are similar or different across countries. Given the recent increase in cohabitation, we pay particular attention to prior cohabitation and marriage, but we also compare age at first union dissolution, first union duration, and presence of children. Methods: Using the Harmonized Histories database, we apply discrete-time hazard models separately by country and to pooled cross-national data. Results: Despite large differences in levels of repartnering, in most countries we find similar associations between demographic characteristics and repartnering. First union type did not matter after controlling for age and children, except in France, where those who previously cohabited had significantly lower risks of repartnering. Age at union dissolution and presence of children are negatively associated with repartnering in almost all countries. Conclusions: Although cohabitation has increased everywhere, prior experience of a coresidential partnership outside of formal marriage makes little difference to repartnering behaviour after controls (except in France. However, regardless of country, older women and/or mothers are less likely to form second unions. Contribution: This study contributes to previous research by examining whether the effects of women

  12. Individual differences in Affective Neuroscience Personality Scale (ANPS) primary emotional traits and depressive tendencies.

    Science.gov (United States)

    Montag, Christian; Widenhorn-Müller, Katharina; Panksepp, Jaak; Kiefer, Markus

    2017-02-01

    The present study investigated individual differences in the Affective Neuroscience Personality Scales (ANPS), representing measures of primary emotional systems, and depressive tendencies in two independent samples. In order to be able to find support for a continuum model with respect to the relation of strength in the cross-species "affective neuroscience" taxonomy of primary emotional systems, we investigated ANPS measured personality traits in a psychologically mostly healthy population (n=614 participants) as well as a sample of clinically depressed people (n=55 depressed patients). In both normal and depressed samples robust associations appeared between higher FEAR and SADNESS scores and depressive tendencies. A similar - albeit weaker - association was observed with lower SEEKING system scores and higher depressive tendencies, an effect again seen in both samples. The study is of cross-sectional nature and therefore only associations between primary emotional systems and depressive tendencies were evaluated. These results show that similar associations between ANPS monitored primary emotional systems and tendencies toward depression can be observed in both healthy and depressed participants. This lends support for a continuum of affective changes accompanying depression, potentially reflecting differences in specific brain emotional system activities in both affectively normal as well as clinically depressed individuals. Copyright © 2016 Elsevier Inc. All rights reserved.

  13. Individual differences in object permanence performance at 8 months: locomotor experience and brain electrical activity.

    Science.gov (United States)

    Bell, M A; Fox, N A

    1997-12-01

    This work was designed to investigate individual differences in hands-and-knees crawling and frontal brain electrical activity with respect to object permanence performance in 76 eight-month-old infants. Four groups of infants (one prelocomotor and 3 with varying lengths of hands-and-knees crawling experience) were tested on an object permanence scale in a research design similar to that used by Kermoian and Campos (1988). In addition, baseline EEG was recorded and used as an indicator of brain development, as in the Bell and Fox (1992) longitudinal study. Individual differences in frontal and occipital EEG power and in locomotor experience were associated with performance on the object permanence task. Infants successful at A-not-B exhibited greater frontal EEG power and greater occipital EEG power than unsuccessful infants. In contrast to Kermoian and Campos (1988), who noted that long-term crawling experience was associated with higher performance on an object permanence scale, infants in this study with any amount of hands and knees crawling experience performed at a higher level on the object permanence scale than prelocomotor infants. There was no interaction among brain electrical activity, locomotor experience, and object permanence performance. These data highlight the value of electrophysiological research and the need for a brain-behavior model of object permanence performance that incorporates both electrophysiological and behavioral factors.

  14. Individual differences and their impact on the safety and the efficiency of human-wheelchair systems.

    Science.gov (United States)

    Jipp, Meike

    2012-12-01

    The extent to which individual differences in fine motor abilities affect indoor safety and efficiency of human-wheelchair systems was examined. To reduce the currently large number of indoor wheelchair accidents, assistance systems with a high level of automation were developed. It was proposed to adapt the wheelchair's level of automation to the user's ability to steer the device to avoid drawbacks of highly automated wheelchairs. The state of the art, however, lacks an empirical identification of those abilities. A study with 23 participants is described. The participants drove through various sections of a course with a powered wheelchair. Repeatedly measured criteria were safety (numbers of collisions) and efficiency (times required for reaching goals). As covariates, the participants' fine motor abilities were assessed. A random coefficient modeling approach was conducted to analyze the data,which were available on two levels as course sections were nested within participants.The participants' aiming, precision, and armhand speed contributed significantly to both criteria: Participants with lower fine motor abilities had more collisions and required more time for reaching goals. Adapting the wheelchair's level of automation to these fine motor abilities can improve indoor safety and efficiency. In addition, the results highlight the need to further examine the impact of individual differences on the design of automation features for powered wheelchairs as well as other applications of automation. The results facilitate the improvement of current wheelchair technology.

  15. Improved Mental Acuity Forecasting with an Individualized Quantitative Sleep Model

    Directory of Open Access Journals (Sweden)

    Brent D. Winslow

    2017-04-01

    Full Text Available Sleep impairment significantly alters human brain structure and cognitive function, but available evidence suggests that adults in developed nations are sleeping less. A growing body of research has sought to use sleep to forecast cognitive performance by modeling the relationship between the two, but has generally focused on vigilance rather than other cognitive constructs affected by sleep, such as reaction time, executive function, and working memory. Previous modeling efforts have also utilized subjective, self-reported sleep durations and were restricted to laboratory environments. In the current effort, we addressed these limitations by employing wearable systems and mobile applications to gather objective sleep information, assess multi-construct cognitive performance, and model/predict changes to mental acuity. Thirty participants were recruited for participation in the study, which lasted 1 week. Using the Fitbit Charge HR and a mobile version of the automated neuropsychological assessment metric called CogGauge, we gathered a series of features and utilized the unified model of performance to predict mental acuity based on sleep records. Our results suggest that individuals poorly rate their sleep duration, supporting the need for objective sleep metrics to model circadian changes to mental acuity. Participant compliance in using the wearable throughout the week and responding to the CogGauge assessments was 80%. Specific biases were identified in temporal metrics across mobile devices and operating systems and were excluded from the mental acuity metric development. Individualized prediction of mental acuity consistently outperformed group modeling. This effort indicates the feasibility of creating an individualized, mobile assessment and prediction of mental acuity, compatible with the majority of current mobile devices.

  16. Causes of individual differences in adolescent optimism: a study in Dutch twins and their siblings.

    Science.gov (United States)

    Mavioğlu, Rezan Nehir; Boomsma, Dorret I; Bartels, Meike

    2015-11-01

    The aim of this study was to investigate the degree to which genetic and environmental influences affect variation in adolescent optimism. Optimism (3 items and 6 items approach) and pessimism were assessed by the Life Orientation Test-Revised (LOT-R) in 5,187 adolescent twins and 999 of their non-twin siblings from the Netherlands Twin Register (NTR). Males reported significantly higher optimism scores than females, while females score higher on pessimism. Genetic structural equation modeling revealed that about one-third of the variance in optimism and pessimism was due to additive genetic effects, with the remaining variance being explained by non-shared environmental effects. A bivariate correlated factor model revealed two dimensions with a genetic correlation of -.57 (CI -.67, -.47), while the non-shared environmental correlation was estimated to be -.21 (CI -.25, -.16). Neither an effect of shared environment, non-additive genetic influences, nor quantitative sex differences was found for both dimensions. This result indicates that individual differences in adolescent optimism are mainly accounted for by non-shared environmental factors. These environmental factors do not contribute to the similarity of family members, but to differences between them. Familial resemblance in optimism and pessimism assessed in adolescents is fully accounted for by genetic overlap between family members.

  17. Individual Differences in the Extent and Development of Aggressive Cognitive-Associative Networks.

    Science.gov (United States)

    Bushman, Brad J.

    1996-01-01

    Extends L. Berkowitz's neoassociationist aggression model by considering the role of personality variables. Experiment one tested the hypothesis that high-trait-aggressive individuals have more developed aggressive cognitive-associative networks than low-trait-aggressive individuals. In experiment two, participants rated the stimulus words used in…

  18. Intra- and Inter-Individual Differences in Adolescent Depressive Mood: the Role of Relationships with Parents and Friends.

    Science.gov (United States)

    Zhang, Shiyu; Baams, Laura; van de Bongardt, Daphne; Dubas, Judith Semon

    2018-05-01

    Utilizing four waves of data from 1126 secondary school Dutch adolescents (Mage = 13.95 at the first wave; 53% boys), the current study examined the interplay between parent-adolescent and friend-adolescent relationship quality (satisfaction and conflict) in relation to adolescents' depressive mood. Using multilevel analyses, the interacting effects of parent/friend relationship quality on depressive mood were tested at both the intra- and inter-individual level. Analyses at the intra-individual level investigated whether individual depressive mood fluctuated along with changes in their social relationships regardless of one's general level of depressive mood; and analyses at the inter-individual level examined whether the average differences in depressive mood between adolescents were associated with different qualities of social relationships. We interpreted the patterns of interactions between parent and friend relationships using four theoretical models: the reinforcement, toxic friends, compensation, and additive model. The results demonstrate the covariation of parent- and friend- relationship quality with adolescents' depressive mood, and highlight that parent and peer effects are not independent from each other-affirming the compensation and additive models at the intra-individual and the reinforcement and additive models at the inter-individual level. The findings highlight the robustness of the protective effects of parent and peer support and the deleterious effects of conflictual relationships for adolescent mental health. The results have implications for both the theoretical and practical design of (preventive) interventions aimed at decreasing adolescents' depressive mood.

  19. Communicative foreign language education for development of individual in different cultures

    International Nuclear Information System (INIS)

    Solovieva, T.S.

    2000-01-01

    In this article the development of the individual in the sphere of nuclear industry and technology is considered on the example of Obninsk Institute of Nuclear Power Engineering as the model of totality of all these factors. (authors)

  20. Temporal symmetry of individual filaments in different spatial symmetry filaments pattern in a dielectric barrier discharge

    International Nuclear Information System (INIS)

    Dong, L. F.; Xiao, H.; Fan, W. L.; Yin, Z. Q.; Zhao, H. T.

    2010-01-01

    The temporal behavior of individual filament in different spatial symmetry filaments patterns in dielectric barrier discharge is investigated by using an optical method. A series of return maps of the discharge moments of individual filaments is given. It is found that the temporal symmetry of individual filament changes with the change of the spatial symmetry of filaments pattern as the applied voltage increases. The role of wall charges for this phenomenon is analyzed.

  1. The complexities of complex span: explaining individual differences in working memory in children and adults.

    Science.gov (United States)

    Bayliss, Donna M; Jarrold, Christopher; Gunn, Deborah M; Baddeley, Alan D

    2003-03-01

    Two studies are presented that investigated the constraints underlying working memory performance in children and adults. In each case, independent measures of processing efficiency and storage capacity are assessed to determine their relative importance in predicting performance on complex span tasks,which measure working memory capacity. Results show that complex span performance was independently constrained by individual differences in domain-general processing efficiency and domain-specific storage capacity. Residual variance, which may reflect the ability to coordinate storage and processing, also predicted academic achievement. These results challenge the view that complex span taps a limited-capacity resource pool shared between processing and storage operations. Rather, they are consistent with a multiple-component model in which separate resource pools support the processing and storage functions of working memory.

  2. State and Trait Effects on Individual Differences in Children's Mathematical Development

    Science.gov (United States)

    Bailey, Drew H.; Watts, Tyler W.; Littlefield, Andrew K.; Geary, David C.

    2015-01-01

    Substantial longitudinal relations between children's early mathematics achievement and their much later mathematics achievement are firmly established. These findings are seemingly at odds with studies showing that early educational interventions have diminishing effects on children's mathematics achievement across time. We hypothesized that individual differences in children's later mathematical knowledge are more an indicator of stable, underlying characteristics related to mathematics learning throughout development than of direct effects of early mathematical competency on later mathematical competency. We tested this hypothesis in two longitudinal data sets, by simultaneously modeling effects of latent traits (stable characteristics that influence learning across time) and states (e.g., prior knowledge) on children's mathematics achievement over time. Latent trait effects on children's mathematical development were substantially larger than state effects. Approximately 60% of the variance in trait mathematics achievement was accounted for by commonly used control variables, such as working memory, but residual trait effects remained larger than state effects. Implications for research and practice are discussed. PMID:25231900

  3. Individual differences in children's emotion understanding: Effects of age and language

    DEFF Research Database (Denmark)

    Pons, Francisco; Lawson, J.: Harris, P.; Rosnay, M. de

    2003-01-01

    Over the last two decades, it has been established that children's emotion understanding changes as they develop. Recent studies have also begun to address individual differences in children's emotion understanding. The first goal of this study was to examine the development of these individual...... differences across a wide age range with a test assessing nine different components of emotion understanding. The second goal was to examine the relation between language ability and individual differences in emotion understanding. Eighty children ranging in age from 4 to 11 years were tested. Children...... displayed a clear improvement with age in both their emotion understanding and language ability. In each age group, there were clear individual differences in emotion understanding and language ability. Age and language ability together explained 72% of emotion understanding variance; 20% of this variance...

  4. Changes in speed distribution: Applying aggregated safety effect models to individual vehicle speeds.

    Science.gov (United States)

    Vadeby, Anna; Forsman, Åsa

    2017-06-01

    This study investigated the effect of applying two aggregated models (the Power model and the Exponential model) to individual vehicle speeds instead of mean speeds. This is of particular interest when the measure introduced affects different parts of the speed distribution differently. The aim was to examine how the estimated overall risk was affected when assuming the models are valid on an individual vehicle level. Speed data from two applications of speed measurements were used in the study: an evaluation of movable speed cameras and a national evaluation of new speed limits in Sweden. The results showed that when applied on individual vehicle speed level compared with aggregated level, there was essentially no difference between these for the Power model in the case of injury accidents. However, for fatalities the difference was greater, especially for roads with new cameras where those driving fastest reduced their speed the most. For the case with new speed limits, the individual approach estimated a somewhat smaller effect, reflecting that changes in the 15th percentile (P15) were somewhat larger than changes in P85 in this case. For the Exponential model there was also a clear, although small, difference between applying the model to mean speed changes and individual vehicle speed changes when speed cameras were used. This applied both for injury accidents and fatalities. There were also larger effects for the Exponential model than for the Power model, especially for injury accidents. In conclusion, applying the Power or Exponential model to individual vehicle speeds is an alternative that provides reasonable results in relation to the original Power and Exponential models, but more research is needed to clarify the shape of the individual risk curve. It is not surprising that the impact on severe traffic crashes was larger in situations where those driving fastest reduced their speed the most. Further investigations on use of the Power and/or the

  5. Individualism: a valid and important dimension of cultural differences between nations.

    Science.gov (United States)

    Schimmack, Ulrich; Oishi, Shigehiro; Diener, Ed

    2005-01-01

    Oyserman, Coon, and Kemmelmeier's (2002) meta-analysis suggested problems in the measurement of individualism and collectivism. Studies using Hofstede's individualism scores show little convergent validity with more recent measures of individualism and collectivism. We propose that the lack of convergent validity is due to national differences in response styles. Whereas Hofstede statistically controlled for response styles, Oyserman et al.'s meta-analysis relied on uncorrected ratings. Data from an international student survey demonstrated convergent validity between Hofstede's individualism dimension and horizontal individualism when response styles were statistically controlled, whereas uncorrected scores correlated highly with the individualism scores in Oyserman et al.'s meta-analysis. Uncorrected horizontal individualism scores and meta-analytic individualism scores did not correlate significantly with nations' development, whereas corrected horizontal individualism scores and Hofstede's individualism dimension were significantly correlated with development. This pattern of results suggests that individualism is a valid construct for cross-cultural comparisons, but that the measurement of this construct needs improvement.

  6. Curious Eyes: Individual Differences in Personality Predict Eye Movement Behavior in Scene-Viewing

    Science.gov (United States)

    Risko, Evan F.; Anderson, Nicola C.; Lanthier, Sophie; Kingstone, Alan

    2012-01-01

    Visual exploration is driven by two main factors--the stimuli in our environment, and our own individual interests and intentions. Research investigating these two aspects of attentional guidance has focused almost exclusively on factors common across individuals. The present study took a different tack, and examined the role played by individual…

  7. Self-Reflection, Insight, and Individual Differences in Various Language Tasks

    Science.gov (United States)

    Xu, Xu

    2011-01-01

    This study explored the relationships of self-reflection and insight with individuals' performances on various language tasks. The Self-Reflection and Insight Scale (SRIS; Grant, Franklin, & Langford, 2002) assessed individual differences in three factors: engagement in reflection, need for reflection, and insight. A high need for reflection was…

  8. Consistency of test behaviour and individual difference in prescision of prediction

    NARCIS (Netherlands)

    Meijer, R.R.

    1998-01-01

    Ghiselli ((1956, 1960) argued that the precision of prediction on the basis of a test may vary for different individuals. To quantify the individual precision of prediction he compared the observed criterion scores with the expected criterion scores estimated on the basis of the total scores on a

  9. Corticostriatal connectivity underlies individual differences in the balance between habitual and goal-directed action control

    NARCIS (Netherlands)

    Wit, S. de; Watson, A.J.P.; Harsay, H.A.; Cohen, M.X.; Vijver, I. van de; Ridderinkhof, K.R.

    2012-01-01

    Why are some individuals more susceptible to the formation of inflexible habits than others? In the present study, we used diffusion tensor imaging to demonstrate that brain connectivity predicts individual differences in relative goal-directed and habitual behavioral control in humans.

  10. Individual-based model for radiation risk assessment

    Science.gov (United States)

    Smirnova, O.

    A mathematical model is developed which enables one to predict the life span probability for mammals exposed to radiation. It relates statistical biometric functions with statistical and dynamic characteristics of an organism's critical system. To calculate the dynamics of the latter, the respective mathematical model is used too. This approach is applied to describe the effects of low level chronic irradiation on mice when the hematopoietic system (namely, thrombocytopoiesis) is the critical one. For identification of the joint model, experimental data on hematopoiesis in nonirradiated and irradiated mice, as well as on mortality dynamics of those in the absence of radiation are utilized. The life span probability and life span shortening predicted by the model agree with corresponding experimental data. Modeling results show the significance of ac- counting the variability of the individual radiosensitivity of critical system cells when estimating the radiation risk. These findings are corroborated by clinical data on persons involved in the elimination of the Chernobyl catastrophe after- effects. All this makes it feasible to use the model for radiation risk assessments for cosmonauts and astronauts on long-term missions such as a voyage to Mars or a lunar colony. In this case the model coefficients have to be determined by making use of the available data for humans. Scenarios for the dynamics of dose accumulation during space flights should also be taken into account.

  11. Individual differences in forced-choice recognition memory: partitioning contributions of recollection and familiarity.

    Science.gov (United States)

    Migo, Ellen M; Quamme, Joel R; Holmes, Selina; Bendell, Andrew; Norman, Kenneth A; Mayes, Andrew R; Montaldi, Daniela

    2014-01-01

    In forced-choice recognition memory, two different testing formats are possible under conditions of high target-foil similarity: Each target can be presented alongside foils similar to itself (forced-choice corresponding; FCC), or alongside foils similar to other targets (forced-choice noncorresponding; FCNC). Recent behavioural and neuropsychological studies suggest that FCC performance can be supported by familiarity whereas FCNC performance is supported primarily by recollection. In this paper, we corroborate this finding from an individual differences perspective. A group of older adults were given a test of FCC and FCNC recognition for object pictures, as well as standardized tests of recall, recognition, and IQ. Recall measures were found to predict FCNC, but not FCC performance, consistent with a critical role for recollection in FCNC only. After the common influence of recall was removed, standardized tests of recognition predicted FCC, but not FCNC performance. This is consistent with a contribution of only familiarity in FCC. Simulations show that a two-process model, where familiarity and recollection make separate contributions to recognition, is 10 times more likely to give these results than a single-process model. This evidence highlights the importance of recognition memory test design when examining the involvement of recollection and familiarity.

  12. Explaining interindividual differences in toddlers’ collaboration with unfamiliar peers: Individual, dyadic, and social factors

    Directory of Open Access Journals (Sweden)

    Nils eSchuhmacher

    2015-05-01

    Full Text Available During their third year of life, toddlers become increasingly skillful at coordinating their actions with peer partners and they form joint commitments in collaborative situations. However, little effort has been made to explain interindividual differences in collaboration among toddlers. Therefore, we examined the relative influence of distinct individual, dyadic, and social factors on toddlers’ collaborative activities (i.e., level of coordination and preference for joint activity in joint problem-solving situations with unfamiliar peer partners (n = 23 dyads aged M = 35.7 months. We analyzed the dyadic nonindependent data with mixed models. Results indicated that mothers’ expectations regarding their children’s social behaviors significantly predicted toddlers’ level of coordination. Furthermore, the models revealed that toddlers’ positive mutual experiences with the unfamiliar partner assessed during an initial free play period (Phase 1 and their level of coordination in an obligatory collaboration task (Phase 2 promoted toddlers’ preference for joint activity in a subsequent optional collaboration task (Phase 3. In contrast, children’s mastery motivation and shyness conflicted with their collaborative efforts. We discuss the role of parents’ socialization goals in toddlers’ development toward becoming active collaborators and discuss possible mechanisms underlying the differences in toddlers’ commitment to joint activities, namely social preferences and the trust in reliable cooperation partners.

  13. Individual differences in associative memory among older adults explained by hippocampal subfield structure and function.

    Science.gov (United States)

    Carr, Valerie A; Bernstein, Jeffrey D; Favila, Serra E; Rutt, Brian K; Kerchner, Geoffrey A; Wagner, Anthony D

    2017-11-07

    Older adults experience impairments in episodic memory, ranging from mild to clinically significant. Given the critical role of the medial temporal lobe (MTL) in episodic memory, age-related changes in MTL structure and function may partially account for individual differences in memory. Using ultra-high-field 7T structural MRI and high-resolution 3T functional MRI (hr-fMRI), we evaluated MTL subfield thickness and function in older adults representing a spectrum of cognitive health. Participants performed an associative memory task during hr-fMRI in which they encoded and later retrieved face-name pairs. Motivated by prior research, we hypothesized that differences in performance would be explained by the following: ( i ) entorhinal cortex (ERC) and CA1 apical neuropil layer [CA1-stratum radiatum lacunosum moleculare (SRLM)] thickness, and ( ii ) activity in ERC and the dentate gyrus (DG)/CA3 region. Regression analyses revealed that this combination of factors significantly accounted for variability in memory performance. Among these metrics, CA1-SRLM thickness was positively associated with memory, whereas DG/CA3 retrieval activity was negatively associated with memory. Furthermore, including structural and functional metrics in the same model better accounted for performance than did single-modality models. These results advance the understanding of how independent but converging influences of both MTL subfield structure and function contribute to age-related memory impairment, complementing findings in the rodent and human postmortem literatures.

  14. Estimation of Nonlinear Dynamic Panel Data Models with Individual Effects

    Directory of Open Access Journals (Sweden)

    Yi Hu

    2014-01-01

    Full Text Available This paper suggests a generalized method of moments (GMM based estimation for dynamic panel data models with individual specific fixed effects and threshold effects simultaneously. We extend Hansen’s (Hansen, 1999 original setup to models including endogenous regressors, specifically, lagged dependent variables. To address the problem of endogeneity of these nonlinear dynamic panel data models, we prove that the orthogonality conditions proposed by Arellano and Bond (1991 are valid. The threshold and slope parameters are estimated by GMM, and asymptotic distribution of the slope parameters is derived. Finite sample performance of the estimation is investigated through Monte Carlo simulations. It shows that the threshold and slope parameter can be estimated accurately and also the finite sample distribution of slope parameters is well approximated by the asymptotic distribution.

  15. Conceptual Models of the Individual Public Service Provider

    DEFF Research Database (Denmark)

    Andersen, Lotte Bøgh; Pedersen, Lene Holm; Bhatti, Yosef

    are used to gain insight on the motivation of public service providers; namely principal-agent theory, self-determination theory and public service motivation theory. We situate the theoretical discussions in the context of public service providers being transferred to private organizations......Individual public service providers’ motivation can be conceptualized as either extrinsic, autonomous or prosocial, and the question is how we can best theoretically understand this complexity without losing too much coherence and parsimony. Drawing on Allison’s approach (1969), three perspectives...... theoretical – to develop a coherent model of individual public service providers – but the empirical illustration also contributes to our understanding of motivation in the context of public sector outsourcing....

  16. Individual Differences in Developmental Change: Quantifying the Amplitude and Heterogeneity in Cognitive Change across Old Age

    Directory of Open Access Journals (Sweden)

    Nathalie Mella

    2018-02-01

    Full Text Available It is well known that cognitive decline in older adults is of smaller amplitude in longitudinal than in cross-sectional studies. Yet, the measure of interest rests generally with aggregated group data. A focus on individual developmental trajectories is rare, mainly because it is difficult to assess intraindividual change reliably. Individual differences in developmental trajectories may differ quantitatively (e.g., larger or smaller decline or qualitatively (e.g., decline vs improvement, as well as in the degree of heterogeneity of change across different cognitive domains or different tasks. The present paper aims at exploring, within the Geneva Variability Study, individual change across several cognitive domains in 92 older adults (aged 59–89 years at baseline over a maximum of seven years and a half. Two novel, complementary methods were used to explore change in cognitive performance while remaining entirely at the intra-individual level. A bootstrap based confidence interval was estimated, for each participant and for each experimental condition, making it possible to define three patterns: stability, increase or decrease in performance. Within-person ANOVAs were also conducted for each individual on all the tasks. Those two methods allowed quantifying the direction, the amplitude and the heterogeneity of change for each individual. Results show that trajectories differed widely among individuals and that decline is far from being the rule.

  17. Individual differences in cyber security behaviors: an examination of who is sharing passwords.

    Science.gov (United States)

    Whitty, Monica; Doodson, James; Creese, Sadie; Hodges, Duncan

    2015-01-01

    In spite of the number of public advice campaigns, researchers have found that individuals still engage in risky password practices. There is a dearth of research available on individual differences in cyber security behaviors. This study focused on the risky practice of sharing passwords. As predicted, we found that individuals who scored high on a lack of perseverance were more likely to share passwords. Contrary to our hypotheses, we found younger [corrected] people and individuals who score high on self-monitoring were more likely to share passwords. We speculate on the reasons behind these findings, and examine how they might be considered in future cyber security educational campaigns.

  18. Effects of emotion regulation strategies on music-elicited emotions: An experimental study explaining individual differences

    NARCIS (Netherlands)

    Karreman, A.; Laceulle, O.M.; Hanser, Waldie; Vingerhoets, Ad

    This experimental study examined if emotional experience can be manipulated by applying an emotion regulation strategy during music listening and if individual differences in effects of strategies can be explained by person characteristics. Adults (N = 466) completed questionnaires and rated

  19. Effects of emotion regulation strategies on music elicited emotions : An experimental study explaining individual differences

    NARCIS (Netherlands)

    Karreman, A.; Laceulle, O.M.; Hanser, W.E.; Vingerhoets, A.J.J.M.

    2017-01-01

    This experimental study examined if emotional experience can be manipulated by applying an emotion regulation strategy during music listening and if individual differences in effects of strategies can be explained by person characteristics. Adults (N = 466) completed questionnaires and rated

  20. Individual differences in processing coherence markers: the effect of metacognitive knowledge

    NARCIS (Netherlands)

    Vlaar, M.A.J.|info:eu-repo/dai/nl/412585669; Sanders, T.J.M.|info:eu-repo/dai/nl/075243911; Welie, Camille

    2017-01-01

    Coherence markers such as connectives positively influence the reading process and reading comprehension for most, but not all, readers. Metacognitive knowledge, concerning strategies to regulate the reading process, may explain these individual differences. We investigated how metacognitive

  1. An implicit test of UX: individuals differ in what they associate with computers

    NARCIS (Netherlands)

    Schmettow, Martin; Noordzij, Matthijs Leendert; Mundt, M.

    2013-01-01

    User experience research has made considerable progress in understanding subjective experience with interactive technology. Nevertheless, we argue, some blind spots have remained: individual differences are frequently ignored, the prevalent measures of self-report rarely undergo verification, and

  2. Individual differences in the peripheral immune system promote resilience versus susceptibility to social stress.

    Science.gov (United States)

    Hodes, Georgia E; Pfau, Madeline L; Leboeuf, Marylene; Golden, Sam A; Christoffel, Daniel J; Bregman, Dana; Rebusi, Nicole; Heshmati, Mitra; Aleyasin, Hossein; Warren, Brandon L; Lebonté, Benoit; Horn, Sarah; Lapidus, Kyle A; Stelzhammer, Viktoria; Wong, Erik H F; Bahn, Sabine; Krishnan, Vaishnav; Bolaños-Guzman, Carlos A; Murrough, James W; Merad, Miriam; Russo, Scott J

    2014-11-11

    Depression and anxiety disorders are associated with increased release of peripheral cytokines; however, their functional relevance remains unknown. Using a social stress model in mice, we find preexisting individual differences in the sensitivity of the peripheral immune system that predict and promote vulnerability to social stress. Cytokine profiles were obtained 20 min after the first social stress exposure. Of the cytokines regulated by stress, IL-6 was most highly up-regulated only in mice that ultimately developed a susceptible behavioral phenotype following a subsequent chronic stress, and levels remained elevated for at least 1 mo. We confirmed a similar elevation of serum IL-6 in two separate cohorts of patients with treatment-resistant major depressive disorder. Before any physical contact in mice, we observed individual differences in IL-6 levels from ex vivo stimulated leukocytes that predict susceptibility versus resilience to a subsequent stressor. To shift the sensitivity of the peripheral immune system to a pro- or antidepressant state, bone marrow (BM) chimeras were generated by transplanting hematopoietic progenitor cells from stress-susceptible mice releasing high IL-6 or from IL-6 knockout (IL-6(-/-)) mice. Stress-susceptible BM chimeras exhibited increased social avoidance behavior after exposure to either subthreshold repeated social defeat stress (RSDS) or a purely emotional stressor termed witness defeat. IL-6(-/-) BM chimeric and IL-6(-/-) mice, as well as those treated with a systemic IL-6 monoclonal antibody, were resilient to social stress. These data establish that preexisting differences in stress-responsive IL-6 release from BM-derived leukocytes functionally contribute to social stress-induced behavioral abnormalities.

  3. Individual differences and repeatability in vocal production: stress-induced calling exposes a songbird's personality

    Science.gov (United States)

    Guillette, Lauren M.; Sturdy, Christopher B.

    2011-11-01

    Recent research in songbirds has demonstrated that male singing behavior varies systematically with personality traits such as exploration and risk taking. Here we examine whether the production of bird calls, in addition to bird songs, is repeatable and related to exploratory behavior, using the black-capped chickadee ( Poecile atricapillus) as a model. We assessed the exploratory behavior of individual birds in a novel environment task. We then recorded the vocalizations and accompanying motor behavior of both male and female chickadees, over the course of several days, in two different contexts: a control condition with no playback and a stressful condition where chick-a-dee mobbing calls were played to individual birds. We found that several vocalizations and behaviors were repeatable within both a control and a stressful context, and across contexts. While there was no relationship between vocal output and exploratory behavior in the control context, production of alarm and chick-a-dee calls in the stressful condition was positively associated with exploratory behavior. These findings are important because they show that bird calls, in addition to bird song, are an aspect of personality, in that calls are consistent both within and across contexts, and covary with other personality measures (exploration).

  4. Individual differences in early adolescents' latent trait cortisol: Interaction of early adversity and 5-HTTLPR.

    Science.gov (United States)

    Chen, Frances R; Stroud, Catherine B; Vrshek-Schallhorn, Suzanne; Doane, Leah D; Granger, Douglas A

    2017-10-01

    The present study aimed to examine the interaction of 5-HTTLPR and early adversity on trait-like levels of cortisol. A community sample of 117 early adolescent girls (M age=12.39years) provided DNA samples for 5-HTTLPR genotyping, and saliva samples for assessing cortisol 3 times a day (waking, 30min post-waking, and bedtime) over a three-day period. Latent trait cortisol (LTC) was modeled using the first 2 samples of each day. Early adversity was assessed with objective contextual stress interviews with adolescents and their mothers. A significant 5-HTTLPR×early adversity interaction indicated that greater early adversity was associated with lower LTC levels, but only among individuals with either L/L or S/L genotype. Findings suggest that serotonergic genetic variation may influence the impact of early adversity on individual differences in HPA-axis regulation. Future research should explore whether this interaction contributes to the development of psychopathology through HPA axis functioning. Copyright © 2017 Elsevier B.V. All rights reserved.

  5. Making workplaces safer: The influence of organisational climate and individual differences on safety behaviour

    Directory of Open Access Journals (Sweden)

    Michelle Ann Toppazzini

    2017-06-01

    Full Text Available Current work health and safety practices focus predominately on fostering a safety climate to promote safety behaviours and reduce workplace accidents. Despite the importance of safety climates in accident prevention, recent research has demonstrated that individual factors can also predict work safety behaviour. This study considered the importance of organisational climate together with individual characteristics including differences in personality, impulsiveness, and perceptions of safety within the workplace on safety behaviour. 203 participants consisting of 67 males and 136 females aged 18 to 71 years, completed an online questionnaire. Results revealed that safety behaviour was directly related to safety climate, and conscientiousness. In contrast, neuroticism, and impulsiveness were not significantly related to safety behaviour. The present study findings support previous findings in the literature regarding the importance of safety climate as well as the personality trait of conscientiousness in applying safety behaviours. However, the present study findings did not support previous research in relation to the personality trait of high neuroticism resulting in decreased safety behaviour, nor did not confirm an inverse relationship between high impulsivity and low safety behaviour as theoretical models would suggest. This new finding may warrant further research into the precursors for safety behaviour. Keywords: Psychology, Sociology, Industry

  6. A neurogenetics approach to understanding individual differences in brain, behavior, and risk for psychopathology.

    Science.gov (United States)

    Bogdan, R; Hyde, L W; Hariri, A R

    2013-03-01

    Neurogenetics research has begun to advance our understanding of how genetic variation gives rise to individual differences in brain function, which, in turn, shapes behavior and risk for psychopathology. Despite these advancements, neurogenetics research is currently confronted by three major challenges: (1) conducting research on individual variables with small effects, (2) absence of detailed mechanisms, and (3) a need to translate findings toward greater clinical relevance. In this review, we showcase techniques and developments that address these challenges and highlight the benefits of a neurogenetics approach to understanding brain, behavior and psychopathology. To address the challenge of small effects, we explore approaches including incorporating the environment, modeling epistatic relationships and using multilocus profiles. To address the challenge of mechanism, we explore how non-human animal research, epigenetics research and genome-wide association studies can inform our mechanistic understanding of behaviorally relevant brain function. Finally, to address the challenge of clinical relevance, we examine how neurogenetics research can identify novel therapeutic targets and for whom treatments work best. By addressing these challenges, neurogenetics research is poised to exponentially increase our understanding of how genetic variation interacts with the environment to shape the brain, behavior and risk for psychopathology.

  7. Escape Distance in Ground-Nesting Birds Differs with Individual Level of Camouflage.

    Science.gov (United States)

    Wilson-Aggarwal, Jared K; Troscianko, Jolyon T; Stevens, Martin; Spottiswoode, Claire N

    2016-08-01

    Camouflage is one of the most widespread antipredator strategies in the animal kingdom, yet no animal can match its background perfectly in a complex environment. Therefore, selection should favor individuals that use information on how effective their camouflage is in their immediate habitat when responding to an approaching threat. In a field study of African ground-nesting birds (plovers, coursers, and nightjars), we tested the hypothesis that individuals adaptively modulate their escape behavior in relation to their degree of background matching. We used digital imaging and models of predator vision to quantify differences in color, luminance, and pattern between eggs and their background, as well as the plumage of incubating adult nightjars. We found that plovers and coursers showed greater escape distances when their eggs were a poorer pattern match to the background. Nightjars sit on their eggs until a potential threat is nearby, and, correspondingly, they showed greater escape distances when the pattern and color match of the incubating adult's plumage-rather than its eggs-was a poorer match to the background. Finally, escape distances were shorter in the middle of the day, suggesting that escape behavior is mediated by both camouflage and thermoregulation.

  8. A locus coeruleus-norepinephrine account of individual differences in working memory capacity and attention control.

    Science.gov (United States)

    Unsworth, Nash; Robison, Matthew K

    2017-08-01

    Studies examining individual differences in working memory capacity (WMC) have suggested that low WMC individuals have particular deficits in attention control processes compared to high WMC individuals. In the current article we suggest that part of the WMC-attention control relation is due to variation in the functioning of the locus coeruleus-norepinephrine system (LC-NE). Specifically, we suggest that because of dysregulation of LC-NE functioning, the fronto-parietal control network for low WMC individuals is only weakly activated, resulting in greater default-mode network activity (and greater mind-wandering) for low WMC individuals compared to high WMC individuals. This results in disrupted attention control and overall more erratic performance (more lapses of attention) for low WMC individuals than for high WMC individuals. This framework is used to examine previous studies of individual differences in WMC and attention control, and new evidence is examined on the basis of predictions of the framework to pupillary responses as an indirect marker of LC-NE functioning.

  9. Individual Differences in Social, Cognitive, and Morphological Aspects of Infant Pointing

    Science.gov (United States)

    Liszkowski, Ulf; Tomasello, Michael

    2011-01-01

    Little is known about the origins of the pointing gesture. We sought to gain insight into its emergence by investigating individual differences in the pointing of 12-month-old infants in two ways. First, we looked at differences in the communicative and interactional uses of pointing and asked how different hand shapes relate to point frequency,…

  10. Examining the linguistic coding differences hypothesis to explain individual differences in foreign language learning.

    Science.gov (United States)

    Sparks, R L

    1995-01-01

    In this paper, it is suggested that foreign language learning problems result from difficulties with native language learning and hypothesized that difficulties with phonological processing may be the locus of foreign language learning difficulties for some poor foreign language learners. Evidence is described that supports these positions. It is argued that conceptualizing foreign language learning problems as alanguage problem allows researchers to more clearly specify deficits related to the learning of a foreign language. Research evidence which shows that good and poor foreign language learners exhibit significantly different levels of native language skill and phonological processing is summarized. Finally, potential challenges to my hypotheses as an explanation for foreign language learning problems are reviewed.

  11. Individual-based modeling of fish: Linking to physical models and water quality.

    Energy Technology Data Exchange (ETDEWEB)

    Rose, K.A.

    1997-08-01

    The individual-based modeling approach for the simulating fish population and community dynamics is gaining popularity. Individual-based modeling has been used in many other fields, such as forest succession and astronomy. The popularity of the individual-based approach is partly a result of the lack of success of the more aggregate modeling approaches traditionally used for simulating fish population and community dynamics. Also, recent recognition that it is often the atypical individual that survives has fostered interest in the individual-based approach. Two general types of individual-based models are distribution and configuration. Distribution models follow the probability distributions of individual characteristics, such as length and age. Configuration models explicitly simulate each individual; the sum over individuals being the population. DeAngelis et al (1992) showed that, when distribution and configuration models were formulated from the same common pool of information, both approaches generated similar predictions. The distribution approach was more compact and general, while the configuration approach was more flexible. Simple biological changes, such as making growth rate dependent on previous days growth rates, were easy to implement in the configuration version but prevented simple analytical solution of the distribution version.

  12. Primate social attention: Species differences and effects of individual experience in humans, great apes, and macaques

    OpenAIRE

    Kano, Fumihiro; Shepherd, Stephen V.; Hirata, Satoshi; Call, Josep

    2018-01-01

    When viewing social scenes, humans and nonhuman primates focus on particular features, such as the models’ eyes, mouth, and action targets. Previous studies reported that such viewing patterns vary significantly across individuals in humans, and also across closely-related primate species. However, the nature of these individual and species differences remains unclear, particularly among nonhuman primates. In large samples of human and nonhuman primates, we examined species differences and th...

  13. Diagnosing differences between business process models

    NARCIS (Netherlands)

    Dijkman, R.M.; Dumas, M.; Reichert, M.; Shan, M.-C.

    2008-01-01

    This paper presents a technique to diagnose differences between business process models in the EPC notation. The diagnosis returns the exact position of a difference in the business process models and diagnoses the type of a difference, using a typology of differences developed in previous work.

  14. Solution strategies as possible explanations of individual and sex differences in a dynamic spatial task.

    Science.gov (United States)

    Peña, Daniel; Contreras, María José; Shih, Pei Chun; Santacreu, José

    2008-05-01

    When individuals perform spatial tasks, individual differences emerge in accuracy and speed as well as in the response patterns used to cope with the task. The purpose of this study is to identify, through empirical criteria, the different response patterns or strategies used by individuals when performing the dynamic spatial task presented in the Spatial Orientation Dynamic Test-Revised (SODT-R). Results show that participants can be classified according to their response patterns. Three different ways of solving a task are described, and their relation to (a) performance factors (response latency, response frequency, and invested time) and (b) ability tests (analytical reasoning, verbal reasoning, and spatial estimation) are investigated. Sex differences in response patterns and performance are also analyzed. It is found that the frequency with which men and women employ each one of the strategies described here, is different and statistically significant. Thus, employed strategy plays an important role when interpreting sex differences on dynamic spatial tasks.

  15. Analytical models approximating individual processes: a validation method.

    Science.gov (United States)

    Favier, C; Degallier, N; Menkès, C E

    2010-12-01

    Upscaling population models from fine to coarse resolutions, in space, time and/or level of description, allows the derivation of fast and tractable models based on a thorough knowledge of individual processes. The validity of such approximations is generally tested only on a limited range of parameter sets. A more general validation test, over a range of parameters, is proposed; this would estimate the error induced by the approximation, using the original model's stochastic variability as a reference. This method is illustrated by three examples taken from the field of epidemics transmitted by vectors that bite in a temporally cyclical pattern, that illustrate the use of the method: to estimate if an approximation over- or under-fits the original model; to invalidate an approximation; to rank possible approximations for their qualities. As a result, the application of the validation method to this field emphasizes the need to account for the vectors' biology in epidemic prediction models and to validate these against finer scale models. Copyright © 2010 Elsevier Inc. All rights reserved.

  16. Individual differences and their measurement: A review of 100 years of research.

    Science.gov (United States)

    Sackett, Paul R; Lievens, Filip; Van Iddekinge, Chad H; Kuncel, Nathan R

    2017-03-01

    This article reviews 100 years of research on individual differences and their measurement, with a focus on research published in the Journal of Applied Psychology. We focus on 3 major individual differences domains: (a) knowledge, skill, and ability, including both the cognitive and physical domains; (b) personality, including integrity, emotional intelligence, stable motivational attributes (e.g., achievement motivation, core self-evaluations), and creativity; and (c) vocational interests. For each domain, we describe the evolution of the domain across the years and highlight major theoretical, empirical, and methodological developments, including relationships between individual differences and variables such as job performance, job satisfaction, and career development. We conclude by discussing future directions for individual differences research. Trends in the literature include a growing focus on substantive issues rather than on the measurement of individual differences, a differentiation between constructs and measurement methods, and the use of innovative ways of assessing individual differences, such as simulations, other-reports, and implicit measures. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

  17. Dynamic functional connectivity and individual differences in emotions during social stress.

    Science.gov (United States)

    Tobia, Michael J; Hayashi, Koby; Ballard, Grey; Gotlib, Ian H; Waugh, Christian E

    2017-12-01

    Exposure to acute stress induces multiple emotional responses, each with their own unique temporal dynamics. Dynamic functional connectivity (dFC) measures the temporal variability of network synchrony and captures individual differences in network neurodynamics. This study investigated the relationship between dFC and individual differences in emotions induced by an acute psychosocial stressor. Sixteen healthy adult women underwent fMRI scanning during a social evaluative threat (SET) task, and retrospectively completed questionnaires that assessed individual differences in subjectively experienced positive and negative emotions about stress and stress relief during the task. Group dFC was decomposed with parallel factor analysis (PARAFAC) into 10 components, each with a temporal signature, spatial network of functionally connected regions, and vector of participant loadings that captures individual differences in dFC. Participant loadings of two networks were positively correlated with stress-related emotions, indicating the existence of networks for positive and negative emotions. The emotion-related networks involved the ventromedial prefrontal cortex, cingulate cortex, anterior insula, and amygdala, among other distributed brain regions, and time signatures for these emotion-related networks were uncorrelated. These findings demonstrate that individual differences in stress-induced positive and negative emotions are each uniquely associated with large-scale brain networks, and suggest that dFC is a mechanism that generates individual differences in the emotional components of the stress response. Hum Brain Mapp 38:6185-6205, 2017. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

  18. Individual differences and predictors of forgetting in old age: the role of processing speed and working memory.

    Science.gov (United States)

    Zimprich, Daniel; Kurtz, Tanja

    2013-01-01

    The goal of the present study was to examine whether individual differences in basic cognitive abilities, processing speed, and working memory, are reliable predictors of individual differences in forgetting rates in old age. The sample for the present study comprised 364 participants aged between 65 and 80 years from the Zurich Longitudinal Study on Cognitive Aging. The impact of basic cognitive abilities on forgetting was analyzed by modeling working memory and processing speed as predictors of the amount of forgetting of 27 words, which had been learned across five trials. Forgetting was measured over a 30-minute interval by using parceling and a latent change model, in which the latent difference between recall performance after five learning trials and a delayed recall was modeled. Results implied reliable individual differences in forgetting. These individual differences in forgetting were strongly related to processing speed and working memory. Moreover, an age-related effect, which was significantly stronger for forgetting than for learning, emerged even after controlling effects of processing speed and working memory.

  19. Differences in adjustment between individuals with alpha-1 antitrypsin deficiency (AATD)-associated COPD and non-AATD COPD.

    Science.gov (United States)

    Holm, Kristen E; Borson, Soo; Sandhaus, Robert A; Ford, Dee W; Strange, Charlie; Bowler, Russell P; Make, Barry J; Wamboldt, Frederick S

    2013-04-01

    Smokers who have severe alpha-1 antitrypsin deficiency (AATD) are at risk for developing COPD earlier in life than smokers without AATD, and are likely to experience challenges adjusting to their illness because they are in a highly productive life stage when they are diagnosed with COPD. This study examined whether individuals with AATD-associated COPD differ from individuals with non-AATD COPD with regard to depression, anxiety, dyspnea, and health-related quality of life (HRQL). Cross-sectional data were collected via self-report questionnaires completed by 480 individuals with non-AATD COPD and 578 individuals with AATD-associated COPD under protocols with IRB approval. Multiple linear regression models were used to test whether individuals with non-AATD COPD differed from individuals with AATD-associated COPD with regard to depression, anxiety, dyspnea, and HRQL. All models adjusted for demographic and health characteristics. Individuals with AATD-associated COPD did not report more symptoms of depression or anxiety; however, they did report more dyspnea (B = 0.31, 95% CI = 0.16 to 0.47, p < 0.001) and impairment in HRQL (B = 4.75, 95% CI = 2.10 to 7.41, p < 0.001) than other individuals with COPD. Individuals with AATD-associated COPD were more likely to be a member of a couple (rather than single) and had a higher level of education when compared to individuals with non-AATD COPD. Resources available to persons with AATD-associated COPD, such as being in a serious relationship and having higher education, may offset the effect of age when considering symptoms of depression and anxiety in patients with COPD.

  20. Differences in Adjustment between Individuals with Alpha-1 Antitrypsin Deficiency (AATD) Associated COPD and Non-AATD COPD

    Science.gov (United States)

    Holm, Kristen E.; Borson, Soo; Sandhaus, Robert A.; Ford, Dee W.; Strange, Charlie; Bowler, Russell P.; Make, Barry J.; Wamboldt, Frederick S.

    2013-01-01

    Smokers who have severe alpha-1 antitrypsin deficiency (AATD) are at risk for developing COPD earlier in life than smokers without AATD, and are likely to experience challenges adjusting to their illness because they are in a highly productive life stage when they are diagnosed with COPD. This study examined whether individuals with AATD-associated COPD differ from individuals with non-AATD COPD with regard to depression, anxiety, dyspnea, and health-related quality of life (HRQL). Cross-sectional data were collected via self-report questionnaires completed by 480 individuals with non-AATD COPD and 578 individuals with AATD-associated COPD under protocols with IRB approval. Multiple linear regression models were used to test whether individuals with non-AATD COPD differed from individuals with AATD-associated COPD with regard to depression, anxiety, dyspnea, and HRQL. All models adjusted for demographic and health characteristics. Individuals with AATD-associated COPD did not report more symptoms of depression or anxiety; however, they did report more dyspnea (B = 0.31, 95% CI = 0.16 to 0.47, p < 0.001) and impairment in HRQL (B = 4.75, 95% CI = 2.10 to 7.41, p < 0.001) than other individuals with COPD. Individuals with AATD-associated COPD were more likely to be a member of a couple (rather than single) and had a higher level of education when compared to individuals with non-AATD COPD. Resources available to persons with AATD-associated COPD, such as being in a serious relationship and having higher education, may offset the effect of age when considering symptoms of depression and anxiety in patients with COPD. PMID:23547634

  1. Modeling Structural, Dyadic, and Individual Factors: The Inclusion and Exclusion Model of HIV Related Behavior

    OpenAIRE

    Albarracin, Dolores; Tannenbaum, Melanie B.; Glasman, Laura R.; Rothman, Alexander J.

    2010-01-01

    Changing HIV-related behaviors requires addressing the individual, dyadic, and structural influences that shape them. This supplement of AIDS & Behavior presents frameworks that integrate these three influences on behavior. Concepts from these frameworks were selected to model the processes by which structural factors affect individual HIV-related behavior. In the Inclusion/Exclusion Model, material and symbolic inclusions and exclusions (sharing versus denying resources) regulate individuals...

  2. Modeling Individual Differences among Writers Using ReaderBench

    NARCIS (Netherlands)

    Allen, Laura; Dascalu, Mihai; McNamara, Danielle S.; Crossley, Scott; Trausan-Matu, Stefan

    2016-01-01

    The current study builds upon a previous study, which examined the degree to which the lexical properties of students’ essays could predict their vocabulary scores. We expand on this previous research by incorporating new natural language processing indices related to both the surface- and

  3. Working Memory Capacity and Categorization: Individual Differences and Modeling

    Science.gov (United States)

    Lewandowsky, Stephan

    2011-01-01

    Working memory is crucial for many higher-level cognitive functions, ranging from mental arithmetic to reasoning and problem solving. Likewise, the ability to learn and categorize novel concepts forms an indispensable part of human cognition. However, very little is known about the relationship between working memory and categorization, and…

  4. Cognitive Modeling and Task Analysis: Basic Processes and Individual Differences

    National Research Council Canada - National Science Library

    Ackerman, Phillip

    1999-01-01

    ... in a complex-skill environment. The subset of task conditions selected were those that involve basic processes of working memory, task monitoring, and differential loads on spatial reasoning and speed of perceiving...

  5. Omics approaches to individual variation: modeling networks and the virtual patient

    OpenAIRE

    Lehrach, Hans

    2016-01-01

    Every human is unique. We differ in our genomes, environment, behavior, disease history, and past and current medical treatment?a complex catalog of differences that often leads to variations in the way each of us responds to a particular therapy. We argue here that true personalization of drug therapies will rely on ?virtual patient? models based on a detailed characterization of the individual patient by molecular, imaging, and sensor techniques. The models will be based, wherever possible,...

  6. Individual acceptance of the biogas innovation: A structural equation model

    International Nuclear Information System (INIS)

    Emmann, Carsten H.; Arens, Ludwig; Theuvsen, Ludwig

    2013-01-01

    The rapid spread of biogas production in Germany has resulted in an increased public debate over this new business branch. Today the production of biogas is much more controversially debated than several years ago. At the same time it could be proven that even among farmers themselves the acceptance of biogas production in some regions is somewhat dampened due to accompanying “collateral damages”. Therefore, the goal of this paper is to identify relevant influencing factors that determine the acceptance of the innovation “biogas” among farmers by applying a causal analysis. Initial results among the five investigated determinants show that not only an individual attitude toward biogas but also the farmers' personal innovativeness strongly and significantly influences an individual's acceptance of the innovation “biogas”. -- Highlights: •Strong expansion of biogas production based on renewable resources in Germany since 2004. •Low acceptance of biogas production in some regions. •Identification of influencing factors that determine the individual acceptance of the biogas innovation among German farmers. •Compared to existing studies, personal innovativeness was taken into account in the causal model. •Results are important for the further expansion of biogas production in Germany as well as in other countries

  7. Diversity in action: exchange of perspectives and reflections on taxonomies of individual differences.

    Science.gov (United States)

    Uher, Jana; Trofimova, Irina; Sulis, William; Netter, Petra; Pessoa, Luiz; Posner, Michael I; Rothbart, Mary K; Rusalov, Vladimir; Peterson, Isaac T; Schmidt, Louis A

    2018-04-19

    Throughout the last 2500 years, the classification of individual differences in healthy people and their extreme expressions in mental disorders has remained one of the most difficult challenges in science that affects our ability to explore individuals' functioning, underlying psychobiological processes and pathways of development. To facilitate analyses of the principles required for studying individual differences, this theme issue brought together prominent scholars from diverse backgrounds of which many bring unique combinations of cross-disciplinary experiences and perspectives that help establish connections and promote exchange across disciplines. This final paper presents brief commentaries of some of our authors and further scholars exchanging perspectives and reflecting on the contributions of this theme issue.This article is part of the theme issue 'Diverse perspectives on diversity: multi-disciplinary approaches to taxonomies of individual differences'. © 2018 The Author(s).

  8. In Others' Shoes: Do Individual Differences in Empathy and Theory of Mind Shape Social Preferences?

    Science.gov (United States)

    Artinger, Florian; Exadaktylos, Filippos; Koppel, Hannes; Sääksvuori, Lauri

    2014-01-01

    Abundant evidence across the behavioral and social sciences suggests that there are substantial individual differences in pro-social behavior. However, little is known about the psychological mechanisms that underlie social preferences. This paper investigates whether empathy and Theory of Mind shape individual differences in pro-social behavior as conventionally observed in neutrally framed social science experiments. Our results show that individual differences in the capacity for empathy do not shape social preferences. The results qualify the role of Theory of Mind in strategic interaction. We do not only show that fair individuals exhibit more accurate beliefs about the behavior of others but that Theory of Mind can be effectively used to pursue both self-interest and pro-social goals depending on the principle objectives of a person. PMID:24743312

  9. Moral values are associated with individual differences in regional brain volume.

    Science.gov (United States)

    Lewis, Gary J; Kanai, Ryota; Bates, Timothy C; Rees, Geraint

    2012-08-01

    Moral sentiment has been hypothesized to reflect evolved adaptations to social living. If so, individual differences in moral values may relate to regional variation in brain structure. We tested this hypothesis in a sample of 70 young, healthy adults examining whether differences on two major dimensions of moral values were significantly associated with regional gray matter volume. The two clusters of moral values assessed were "individualizing" (values of harm/care and fairness) and "binding" (deference to authority, in-group loyalty, and purity/sanctity). Individualizing was positively associated with left dorsomedial pFC volume and negatively associated with bilateral precuneus volume. For binding, a significant positive association was found for bilateral subcallosal gyrus and a trend to significance for the left anterior insula volume. These findings demonstrate that variation in moral sentiment reflects individual differences in brain structure and suggest a biological basis for moral sentiment, distributed across multiple brain regions.

  10. In others' shoes: do individual differences in empathy and theory of mind shape social preferences?

    Science.gov (United States)

    Artinger, Florian; Exadaktylos, Filippos; Koppel, Hannes; Sääksvuori, Lauri

    2014-01-01

    Abundant evidence across the behavioral and social sciences suggests that there are substantial individual differences in pro-social behavior. However, little is known about the psychological mechanisms that underlie social preferences. This paper investigates whether empathy and Theory of Mind shape individual differences in pro-social behavior as conventionally observed in neutrally framed social science experiments. Our results show that individual differences in the capacity for empathy do not shape social preferences. The results qualify the role of Theory of Mind in strategic interaction. We do not only show that fair individuals exhibit more accurate beliefs about the behavior of others but that Theory of Mind can be effectively used to pursue both self-interest and pro-social goals depending on the principle objectives of a person.

  11. Individual Differences in Automatic Emotion Regulation Interact with Primed Emotion Regulation during an Anger Provocation

    Directory of Open Access Journals (Sweden)

    Ping Hu

    2017-04-01

    Full Text Available The current study investigated the interactive effects of individual differences in automatic emotion regulation (AER and primed emotion regulation strategy on skin conductance level (SCL and heart rate during provoked anger. The study was a 2 × 2 [AER tendency (expression vs. control × priming (expression vs. control] between subject design. Participants were assigned to two groups according to their performance on an emotion regulation-IAT (differentiating automatic emotion control tendency and automatic emotion expression tendency. Then participants of the two groups were randomly assigned to two emotion regulation priming conditions (emotion control priming or emotion expression priming. Anger was provoked by blaming participants for slow performance during a subsequent backward subtraction task. In anger provocation, SCL of individuals with automatic emotion control tendencies in the control priming condition was lower than of those with automatic emotion control tendencies in the expression priming condition. However, SCL of individuals with automatic emotion expression tendencies did no differ in the automatic emotion control priming or the automatic emotion expression priming condition. Heart rate during anger provocation was higher in individuals with automatic emotion expression tendencies than in individuals with automatic emotion control tendencies regardless of priming condition. This pattern indicates an interactive effect of individual differences in AER and emotion regulation priming on SCL, which is an index of emotional arousal. Heart rate was only sensitive to the individual differences in AER, and did not reflect this interaction. This finding has implications for clinical studies of the use of emotion regulation strategy training suggesting that different practices are optimal for individuals who differ in AER tendencies.

  12. Metabolomics Reveals Metabolically Healthy and Unhealthy Obese Individuals Differ in their Response to a Caloric Challenge.

    Directory of Open Access Journals (Sweden)

    Flavia Badoud

    Full Text Available To determine if metabolically healthy obese (MHO individuals have a different metabolic response to a standardized diet compared to lean healthy (LH and metabolically unhealthy obese (MUO individuals.Thirty adults (35-70 yrs were classified as LH, MHO, and MUO according to anthropometric and clinical measurements. Participants consumed a standardized high calorie meal (~1330 kcal. Blood glucose and insulin were measured at fasting, and 15, 30, 60, 90 and 120 min postprandially. Additional blood samples were collected for the targeted analysis of amino acids (AAs and derivatives, and fatty acids (FAs.The postprandial response (i.e., area under the curve, AUC for serum glucose and insulin were similar between MHO and LH individuals, and significantly lower than MUO individuals (p < 0.05. Minor differences were found in postprandial responses for AAs between MHO and MUO individuals, while three polyunsaturated FAs (linoleic acid, γ-linolenic acid, arachidonic acid showed smaller changes in serum after the meal in MHO individuals compared to MUO. Fasting levels for various AAs (notably branched-chain AA and FAs (e.g., saturated myristic and palmitic acids were found to correlate with glucose and insulin AUC.MHO individuals show preserved insulin sensitivity and a greater ability to adapt to a caloric challenge compared to MUO individuals.

  13. Individual Travel Behavior Modeling of Public Transport Passenger Based on Graph Construction

    OpenAIRE

    Quan Liang; Jiancheng Weng; Wei Zhou; Selene Baez Santamaria; Jianming Ma; Jian Rong

    2018-01-01

    This paper presents a novel method for mining the individual travel behavior regularity of different public transport passengers through constructing travel behavior graph based model. The individual travel behavior graph is developed to represent spatial positions, time distributions, and travel routes and further forecasts the public transport passenger’s behavior choice. The proposed travel behavior graph is composed of macronodes, arcs, and transfer probability. Each macronode corresponds...

  14. Regional Brain Shrinkage over Two Years: Individual Differences and Effects of Pro-Inflammatory Genetic Polymorphisms

    Science.gov (United States)

    Persson, N.; Ghisletta, P.; Dahle, C.L.; Bender, A.R.; Yang, Y.; Yuan, P.; Daugherty, A.M.; Raz, N.

    2014-01-01

    We examined regional changes in brain volume in healthy adults (N = 167, age 19-79 years at baseline; N = 90 at follow-up) over approximately two years. With latent change score models, we evaluated mean change and individual differences in rates of change in 10 anatomically-defined and manually-traced regions of interest (ROIs): lateral prefrontal cortex (LPFC), orbital frontal cortex (OF), prefrontal white matter (PFw), hippocampus (HC), parahippocampal gyrus (PhG), caudate nucleus (Cd), putamen (Pt), insula (In), cerebellar hemispheres (CbH), and primary visual cortex (VC). Significant mean shrinkage was observed in the HC, CbH, In, OF, and the PhG, and individual differences in change were noted in all regions, except the OF. Pro-inflammatory genetic variants mediated shrinkage in PhG and CbH. Carriers of two T alleles of interleukin-1β (IL-1βC-511T, rs16944) and a T allele of methylenetetrahydrofolate reductase (MTHFRC677T, rs1801133) polymorphisms showed increased PhG shrinkage. No effects of a pro-inflammatory polymorphism for C-reactive protein (CRP-286C>A>T, rs3091244) or apolipoprotein (APOE) ε4 allele were noted. These results replicate the pattern of brain shrinkage observed in previous studies, with a notable exception of the LPFC thus casting doubt on the unique importance of prefrontal cortex in aging. Larger baseline volumes of CbH and In were associated with increased shrinkage, in conflict with the brain reserve hypothesis. Contrary to previous reports, we observed no significant linear effects of age and hypertension on regional brain shrinkage. Our findings warrant further investigation of the effects of neuroinflammation on structural brain change throughout the lifespan. PMID:25264227

  15. Individual differences in vagal regulation are related to testosterone responses to observed violence

    Directory of Open Access Journals (Sweden)

    Eric C Porges

    2015-02-01

    Full Text Available Observing violent content has been hypothesized to increase antisocial behaviors including interpersonal violence. Testosterone is released in response to perceived challenges of social status, often followed by an increase in aggressive behaviors and physiological activation. Prior investigations evaluating the impact of observing violence on autonomic function have focused on sympathetic measures of arousal. Measurement of parasympathetic nervous system (PNS activity has been neglected, although reduced PNS activity has been associated with antisocial behavior. Consistent with a hierarchical model of the autonomic nervous system (i.e., Polyvagal Theory, individual differences in PNS activity reflected in respiratory sinus arrhythmia (RSA were hypothesized to have an inhibitory impact on sympathetic and hormonal reactivity in subjects who were observing a violent video. Autonomic data (i.e., electrodermal activity (EDA, heart rate, and RSA were collected from forty adult males prior to and while viewing violent sports or a control video. Pre- and post-video saliva samples were assayed for cortisol and testosterone. Participants who viewed the violent video exhibited increased sympathetic activity compared to controls. In contrast to the sympathetic reactivity to the violent video, there were no significant RSA changes in response to the stimuli, suggesting that viewing violent sports selectively increases sympathetic activity without eliciting PNS withdrawal. However, within the group viewing the violent video, participants with lower RSA during baseline and the observation of violent videos, responded with greater increases in salivary testosterone, suggesting that high parasympathetic tone dampens testosterone reactivity. These individual differences in response to observed violence, associated with higher RSA, may account for some of the improved health, growth, and restoration outcomes across the lifespan, that this segment of the

  16. Model-Based Individualized Treatment of Chemotherapeutics: Bayesian Population Modeling and Dose Optimization.

    Directory of Open Access Journals (Sweden)

    Devaraj Jayachandran

    Full Text Available 6-Mercaptopurine (6-MP is one of the key drugs in the treatment of many pediatric cancers, auto immune diseases and inflammatory bowel disease. 6-MP is a prodrug, converted to an active metabolite 6-thioguanine nucleotide (6-TGN through enzymatic reaction involving thiopurine methyltransferase (TPMT. Pharmacogenomic variation observed in the TPMT enzyme produces a significant variation in drug response among the patient population. Despite 6-MP's widespread use and observed variation in treatment response, efforts at quantitative optimization of dose regimens for individual patients are limited. In addition, research efforts devoted on pharmacogenomics to predict clinical responses are proving far from ideal. In this work, we present a Bayesian population modeling approach to develop a pharmacological model for 6-MP metabolism in humans. In the face of scarcity of data in clinical settings, a global sensitivity analysis based model reduction approach is used to minimize the parameter space. For accurate estimation of sensitive parameters, robust optimal experimental design based on D-optimality criteria was exploited. With the patient-specific model, a model predictive control algorithm is used to optimize the dose scheduling with the objective of maintaining the 6-TGN concentration within its therapeutic window. More importantly, for the first time, we show how the incorporation of information from different levels of biological chain-of response (i.e. gene expression-enzyme phenotype-drug phenotype plays a critical role in determining the uncertainty in predicting therapeutic target. The model and the control approach can be utilized in the clinical setting to individualize 6-MP dosing based on the patient's ability to metabolize the drug instead of the traditional standard-dose-for-all approach.

  17. Model-Based Individualized Treatment of Chemotherapeutics: Bayesian Population Modeling and Dose Optimization

    Science.gov (United States)

    Jayachandran, Devaraj; Laínez-Aguirre, José; Rundell, Ann; Vik, Terry; Hannemann, Robert; Reklaitis, Gintaras; Ramkrishna, Doraiswami

    2015-01-01

    6-Mercaptopurine (6-MP) is one of the key drugs in the treatment of many pediatric cancers, auto immune diseases and inflammatory bowel disease. 6-MP is a prodrug, converted to an active metabolite 6-thioguanine nucleotide (6-TGN) through enzymatic reaction involving thiopurine methyltransferase (TPMT). Pharmacogenomic variation observed in the TPMT enzyme produces a significant variation in drug response among the patient population. Despite 6-MP’s widespread use and observed variation in treatment response, efforts at quantitative optimization of dose regimens for individual patients are limited. In addition, research efforts devoted on pharmacogenomics to predict clinical responses are proving far from ideal. In this work, we present a Bayesian population modeling approach to develop a pharmacological model for 6-MP metabolism in humans. In the face of scarcity of data in clinical settings, a global sensitivity analysis based model reduction approach is used to minimize the parameter space. For accurate estimation of sensitive parameters, robust optimal experimental design based on D-optimality criteria was exploited. With the patient-specific model, a model predictive control algorithm is used to optimize the dose scheduling with the objective of maintaining the 6-TGN concentration within its therapeutic window. More importantly, for the first time, we show how the incorporation of information from different levels of biological chain-of response (i.e. gene expression-enzyme phenotype-drug phenotype) plays a critical role in determining the uncertainty in predicting therapeutic target. The model and the control approach can be utilized in the clinical setting to individualize 6-MP dosing based on the patient’s ability to metabolize the drug instead of the traditional standard-dose-for-all approach. PMID:26226448

  18. Snacking now or later? Individual differences in following intentions or habits explained by time perspective.

    Science.gov (United States)

    Onwezen, M C; Van 't Riet, J; Dagevos, H; Sijtsema, S J; Snoek, H M

    2016-12-01

    Even when individuals are aware of long-term health effects of their diet, and form healthy intentions, they often engage in relatively unhealthy snacking habits. Some individuals fall back on unhealthy habits more easily than others. We aim to explore whether time perspective can explain why some individuals are more prone to rely on habits and others on intentions. Study 1 (N = 1503) provides a first exploration of the role of time perspective by exploring individual differences in perception of long-term and short-term consequences. In accordance with our hypotheses, Study 1 shows that habits are associated with short-term consequences and intentions with long-term consequences. Study 2 (N = 1497) shows that the effects of habits on snacking behaviour are strengthened by a present time perspective, whereas the effects of intentions on snacking behaviour are strengthened by a future time perspective. These findings imply that there is a fundamental difference in the guiding function of intentions and habits which might explain individual differences in following intentions versus habits. Individuals with a long-term perspective are more inclined to follow intentions and individuals with a short-term perspective are more inclined to follow habits. Copyright © 2016 Elsevier Ltd. All rights reserved.

  19. Structure and sensitivity analysis of individual-based predator–prey models

    International Nuclear Information System (INIS)

    Imron, Muhammad Ali; Gergs, Andre; Berger, Uta

    2012-01-01

    The expensive computational cost of sensitivity analyses has hampered the use of these techniques for analysing individual-based models in ecology. A relatively cheap computational cost, referred to as the Morris method, was chosen to assess the relative effects of all parameters on the model’s outputs and to gain insights into predator–prey systems. Structure and results of the sensitivity analysis of the Sumatran tiger model – the Panthera Population Persistence (PPP) and the Notonecta foraging model (NFM) – were compared. Both models are based on a general predation cycle and designed to understand the mechanisms behind the predator–prey interaction being considered. However, the models differ significantly in their complexity and the details of the processes involved. In the sensitivity analysis, parameters that directly contribute to the number of prey items killed were found to be most influential. These were the growth rate of prey and the hunting radius of tigers in the PPP model as well as attack rate parameters and encounter distance of backswimmers in the NFM model. Analysis of distances in both of the models revealed further similarities in the sensitivity of the two individual-based models. The findings highlight the applicability and importance of sensitivity analyses in general, and screening design methods in particular, during early development of ecological individual-based models. Comparison of model structures and sensitivity analyses provides a first step for the derivation of general rules in the design of predator–prey models for both practical conservation and conceptual understanding. - Highlights: ► Structure of predation processes is similar in tiger and backswimmer model. ► The two individual-based models (IBM) differ in space formulations. ► In both models foraging distance is among the sensitive parameters. ► Morris method is applicable for the sensitivity analysis even of complex IBMs.

  20. Of goals and habits: Age-related and individual differences in goal-directed decision-making

    Directory of Open Access Journals (Sweden)

    Ben eEppinger

    2013-12-01

    Full Text Available In this study we investigated age-related and individual differences in habitual (model-free and goal-directed (model-based decision-making. Specifically, we were interested in three questions. First, does age affect the balance between model-based and model-free decision mechanisms? Second, are these age-related changes due to age differences in working memory (WM capacity? Third, can model-based behavior be affected by manipulating the distinctiveness of the reward value of choice options? To answer these questions we used a two-stage Markov decision task in in combination with computational modeling to dissociate model-based and model-free decision mechanisms. To affect model-based behavior in this task we manipulated the distinctiveness of reward probabilities of choice options. The results show age-related deficits in model-based decision-making, which are particularly pronounced if unexpected reward indicates the need for a shift in decision strategy. In this situation younger adults explore the task structure, whereas older adults show perseverative behavior. Consistent with previous findings, these results indicate that older adults have deficits in the representation and updating of expected reward value. We also observed substantial individual differences in model-based behavior. In younger adults high WM capacity is associated with greater model-based behavior and this effect is further elevated when reward probabilities are more distinct. However, in older adults we found no effect of WM capacity. Moreover, age differences in model-based behavior remained statistically significant, even after controlling for WM capacity. Thus, factors other than decline in WM, such as deficits in the in the integration of expected reward value into strategic decisions may contribute to the observed impairments in model-based behavior in older adults.

  1. Communicative foreign language education for development of individual in different cultures

    International Nuclear Information System (INIS)

    Solovieva, T.S.

    2001-01-01

    Social changes in community and also in principles of education, psychology of activity and philosophy lead to changes in views on human as a whole, on place of individual in society and on definition of individual itself, on essence of education and on foreign language as business communication mean and separate discipline. In this article the development of the individual in the sphere of nuclear industry and technology is considered on the example of Obninsk Institute of Nuclear Power Engineering as the model of totality of all these factors. (author)

  2. Individual differences in spatial configuration learning predict the occurrence of intrusive memories.

    Science.gov (United States)

    Meyer, Thomas; Smeets, Tom; Giesbrecht, Timo; Quaedflieg, Conny W E M; Girardelli, Marta M; Mackay, Georgina R N; Merckelbach, Harald

    2013-03-01

    The dual-representation model of posttraumatic stress disorder (PTSD; Brewin, Gregory, Lipton, & Burgess, Psychological Review, 117, 210-232 2010) argues that intrusions occur when people fail to construct context-based representations during adverse experiences. The present study tested a specific prediction flowing from this model. In particular, we investigated whether the efficiency of temporal-lobe-based spatial configuration learning would account for individual differences in intrusive experiences and physiological reactivity in the laboratory. Participants (N = 82) completed the contextual cuing paradigm, which assesses spatial configuration learning that is believed to depend on associative encoding in the parahippocampus. They were then shown a trauma film. Afterward, startle responses were quantified during presentation of trauma reminder pictures versus unrelated neutral and emotional pictures. PTSD symptoms were recorded in the week following participation. Better configuration learning performance was associated with fewer perceptual intrusions, r = -.33, p .46) and had no direct effect on intrusion-related distress and overall PTSD symptoms, rs > -.12, ps > .29. However, configuration learning performance tended to be associated with reduced physiological responses to unrelated negative images, r = -.20, p = .07. Thus, while spatial configuration learning appears to be unrelated to affective responding to trauma reminders, our overall findings support the idea that the context-based memory system helps to reduce intrusions.

  3. Linking neurogenetics and individual differences in language learning: the dopamine hypothesis.

    Science.gov (United States)

    Wong, Patrick C M; Morgan-Short, Kara; Ettlinger, Marc; Zheng, Jing

    2012-10-01

    Fundamental advances in neuroscience have come from investigations into neuroplasticity and learning. These investigations often focus on identifying universal principles across different individuals of the same species. Increasingly, individual differences in learning success have also been observed, such that any seemingly universal principle might only be applicable to a certain extent within a particular learner. One potential source of this variation is individuals' genetic differences. Adult language learning provides a unique opportunity for understanding individual differences and genetic bases of neuroplasticity because of the large individual differences in learning success that have already been documented, and because of the body of empirical work connecting language learning and neurocognition. In this article, we review the literature on the genetic bases of neurocognition, especially studies examining polymorphisms of dopamine (DA)-related genes and procedural learning. This review leads us to hypothesize that there may be an association between DA-related genetic variation and language learning differences. If this hypothesis is supported by future empirical findings we suggest that it may point to neurogenetic markers that allow for language learning to be personalized. Copyright © 2012 Elsevier Srl. All rights reserved.

  4. Individual differences in social anxiety affect the salience of errors in social contexts.

    Science.gov (United States)

    Barker, Tyson V; Troller-Renfree, Sonya; Pine, Daniel S; Fox, Nathan A

    2015-12-01

    The error-related negativity (ERN) is an event-related potential that occurs approximately 50 ms after an erroneous response. The magnitude of the ERN is influenced by contextual factors, such as when errors are made during social evaluation. The ERN is also influenced by individual differences in anxiety, and it is elevated among anxious individuals. However, little research has examined how individual differences in anxiety interact with contextual factors to impact the ERN. Social anxiety involves fear and apprehension of social evaluation. In the present study, we explored how individual differences in social anxiety interact with social contexts to modulate the ERN. The ERN was measured in 43 young adults characterized as being either high or low in social anxiety, while they completed a flanker task in two contexts: alone and during social evaluation. The results revealed a significant interaction between social anxiety and context, such that the ERN was enhanced in a social relative to a nonsocial context only among highly socially anxious individuals. Furthermore, the degree of such enhancement significantly correlated with individual differences in social anxiety. These findings demonstrate that social anxiety is characterized by enhanced neural activity to errors in social-evaluative contexts.

  5. Can individual health differences be explained by workplace characteristics?--A multilevel analysis.

    Science.gov (United States)

    Marklund, Staffan; Bolin, Malin; von Essen, Jan

    2008-02-01

    Research on work-related health has mainly focused on individual factors. The present study expands the focus by exploring the role of organizational characteristics of workplaces for different individual health outcomes. The aim of the study was to look at differences in relative effect of workplace variations on five health outcomes, and to explain those differences in health outcomes by organizational characteristics. The sample encompassed 90 workplaces in Sweden and about 4300 individuals employed within these workplaces. Measurement of the workplace characteristics was carried out independently of the measurement of the individual's working conditions and health. Organizational data were collected by interviews with local managers at participating workplaces, and individual data were obtained by means of a survey of the employees. The results showed that a significant proportion of the variance in sickness absence, work ability, general health, and musculoskeletal disorders was attributed to the workplace. Of eight tested organizational characteristics, customer adaptation, lean production, and performance control could explain some of this workplace variance. The results also showed that only one organizational effect remained significant when controlled for the individual confounder of age and gender. High customer adaptation is associated with higher sickness absence. This association is not mediated via differences in mental and physical job strain.

  6. Modeling structured population dynamics using data from unmarked individuals

    Science.gov (United States)

    Grant, Evan H. Campbell; Zipkin, Elise; Thorson, James T.; See, Kevin; Lynch, Heather J.; Kanno, Yoichiro; Chandler, Richard; Letcher, Benjamin H.; Royle, J. Andrew

    2014-01-01

    The study of population dynamics requires unbiased, precise estimates of abundance and vital rates that account for the demographic structure inherent in all wildlife and plant populations. Traditionally, these estimates have only been available through approaches that rely on intensive mark–recapture data. We extended recently developed N-mixture models to demonstrate how demographic parameters and abundance can be estimated for structured populations using only stage-structured count data. Our modeling framework can be used to make reliable inferences on abundance as well as recruitment, immigration, stage-specific survival, and detection rates during sampling. We present a range of simulations to illustrate the data requirements, including the number of years and locations necessary for accurate and precise parameter estimates. We apply our modeling framework to a population of northern dusky salamanders (Desmognathus fuscus) in the mid-Atlantic region (USA) and find that the population is unexpectedly declining. Our approach represents a valuable advance in the estimation of population dynamics using multistate data from unmarked individuals and should additionally be useful in the development of integrated models that combine data from intensive (e.g., mark–recapture) and extensive (e.g., counts) data sources.

  7. Regulatory Flexibility: An Individual Differences Perspective on Coping and Emotion Regulation.

    Science.gov (United States)

    Bonanno, George A; Burton, Charles L

    2013-11-01

    People respond to stressful events in different ways, depending on the event and on the regulatory strategies they choose. Coping and emotion regulation theorists have proposed dynamic models in which these two factors, the person and the situation, interact over time to inform adaptation. In practice, however, researchers have tended to assume that particular regulatory strategies are consistently beneficial or maladaptive. We label this assumption the fallacy of uniform efficacy and contrast it with findings from a number of related literatures that have suggested the emergence of a broader but as yet poorly defined construct that we refer to as regulatory flexibility. In this review, we articulate this broader construct and define both its features and limitations. Specifically, we propose a heuristic individual differences framework and review research on three sequential components of flexibility for which propensities and abilities vary: sensitivity to context, availability of a diverse repertoire of regulatory strategies, and responsiveness to feedback. We consider the methodological limitations of research on each component, review questions that future research on flexibility might address, and consider how the components might relate to each other and to broader conceptualizations about stability and change across persons and situations. © The Author(s) 2013.

  8. Individual differences in motor timing and its relation to cognitive and fine motor skills.

    Directory of Open Access Journals (Sweden)

    Håvard Lorås

    Full Text Available The present study investigated the relationship between individual differences in timing movements at the level of milliseconds and performance on selected cognitive and fine motor skills. For this purpose, young adult participants (N = 100 performed a repetitive movement task paced by an auditory metronome at different rates. Psychometric measures included the digit-span and symbol search subtasks from the Wechsler battery as well as the Raven SPM. Fine motor skills were assessed with the Purdue Pegboard test. Motor timing performance was significantly related (mean r = .3 to cognitive measures, and explained both unique and shared variance with information-processing speed of Raven's scores. No significant relations were found between motor timing measures and fine motor skills. These results show that individual differences in cognitive and motor timing performance is to some extent dependent upon shared processing not associated with individual differences in manual dexterity.

  9. Trait and neurobiological correlates of individual differences in dream recall and dream content.

    Science.gov (United States)

    Blagrove, Mark; Pace-Schott, Edward F

    2010-01-01

    Individuals differ greatly in their dream recall frequency, in their incidence of recalling types of dreams, such as nightmares, and in the content of their dreams. This chapter reviews work on the waking life correlates of these differences between people in their experience of dreaming and reviews some of the neurobiological correlates of these individual differences. The chapter concludes that despite there being trait-like aspects of general dream recall and of dream content, very few psychometrically assessed correlates for dream recall frequency and dream content have been found. More successful has been the investigation of correlates of frequency of particular types of dreams, such as nightmares and lucid dreams, and also of how waking-life experience is associated with dream content. There is also potential in establishing neurobiological correlates of individual differences in dream recall and dream content, and recent work on this is reviewed. Copyright © 2010 Elsevier Inc. All rights reserved.

  10. Individual Differences in Early Adolescents' Beliefs in the Legitimacy of Parental Authority

    Science.gov (United States)

    Kuhn, Emily S.; Laird, Robert D.

    2011-01-01

    Adolescents differ in the extent to which they believe that parents have legitimate authority to impose rules restricting adolescents' behavior. The purpose of the current study was to test predictors of individual differences in legitimacy beliefs during the middle school years. Annually, during the summers following Grades 5, 6, and 7, early…

  11. Individual Differences in Working Memory Capacity and Dual-Process Theories of the Mind

    Science.gov (United States)

    Barrett, Lisa Feldman; Tugade, Michele M.; Engle, Randall W.

    2004-01-01

    Dual-process theories of the mind are ubiquitous in psychology. A central principle of these theories is that behavior is determined by the interplay of automatic and controlled processing. In this article, the authors examine individual differences in the capacity to control attention as a major contributor to differences in working memory…

  12. Current and Historical Antecedents of Individual Value Differences Across 195 Regions in Europe

    NARCIS (Netherlands)

    van Herk, H.; Poortinga, Y.H.

    2012-01-01

    This study analyzes differences on two value dimensions, conservation and self-enhancement, at both the individual and regional level across Europe. Within-country regions represent "cultunits" that often have belonged to different nation-states in history. Eight antecedent variables are explored.

  13. What Produces Television Attention and Attention Style? Genre, Situation, and Individual Differences as Predictors

    Science.gov (United States)

    Hawkins, Robert P.; Pingree, Suzanne; Hitchon, Jacqueline; Radler, Barry; Gorham, Bradley W.; Kahlor, Leeann; Gilligan, Eileen; Serlin, Ronald C.; Schmidt, Toni; Kannaovakun, Prathana; Kolbeins, Gudbjorg Hildur

    2005-01-01

    Individual looks at television vary enormously in length, and this has previously indicated differences in ongoing cognitive processes. Furthermore, the relative frequency of looks of different lengths may indicate styles of attention to television. This article compares visual attention of 152 subjects across a variety of genres and examines…

  14. Individual Differences in Strategy Use on Division Problems: Mental versus Written Computation

    Science.gov (United States)

    Hickendorff, Marian; van Putten, Cornelis M.; Verhelst, Norman D.; Heiser, Willem J.

    2010-01-01

    Individual differences in strategy use (choice and accuracy) were analyzed. A sample of 362 Grade 6 students solved complex division problems under 2 different conditions. In the choice condition students were allowed to use either a mental or a written strategy. In the subsequent no-choice condition, they were required to use a written strategy.…

  15. Perspectives on Individual Differences Affecting Therapeutic Change in Communication Disorders. New Directions in Communication Disorders Research

    Science.gov (United States)

    Weiss, Amy L., Ed.

    2009-01-01

    This volume examines the ramifications of individual differences in therapy outcomes for a wide variety of communication disorders. In an era where evidence-based practice is the clinical profession's watchword, each chapter attacks this highly relevant issue from a somewhat different perspective. In some areas of communication disorders,…

  16. Individual Differences and Learning Contexts: A Self-Regulated Learning Perspective

    Science.gov (United States)

    Ben-Eliyahu, Adar

    2017-01-01

    This article examines how individual differences (giftedness) interact with learning contexts (favorite versus least favorite courses) to influence learning processes and outcomes. The findings show that gifted and typically developing students differ solely in their expectancies for success and grades among a large variety of measures, including…

  17. Modeling decisions from experience: How models with a set of parameters for aggregate choices explain individual choices

    Directory of Open Access Journals (Sweden)

    Neha Sharma

    2017-10-01

    Full Text Available One of the paradigms (called “sampling paradigm” in judgment and decision-making involves decision-makers sample information before making a final consequential choice. In the sampling paradigm, certain computational models have been proposed where a set of single or distribution parameters is calibrated to the choice proportions of a group of participants (aggregate and hierarchical models. However, currently little is known on how aggregate and hierarchical models would account for choices made by individual participants in the sampling paradigm. In this paper, we test the ability of aggregate and hierarchical models to explain choices made by individual participants. Several models, Ensemble, Cumulative Prospect Theory (CPT, Best Estimation and Simulation Techniques (BEAST, Natural-Mean Heuristic (NMH, and Instance-Based Learning (IBL, had their parameters calibrated to individual choices in a large dataset involving the sampling paradigm. Later, these models were generalized to two large datasets in the sampling paradigm. Results revealed that the aggregate models (like CPT and IBL accounted for individual choices better than hierarchical models (like Ensemble and BEAST upon generalization to problems that were like those encountered during calibration. Furthermore, the CPT model, which relies on differential valuing of gains and losses, respectively, performed better than other models during calibration and generalization on datasets with similar set of problems. The IBL model, relying on recency and frequency of sampled information, and the NMH model, relying on frequency of sampled information, performed better than other models during generalization to a challenging dataset. Sequential analyses of results from different models showed how these models accounted for transitions from the last sample to final choice in human data. We highlight the implications of using aggregate and hierarchical models in explaining individual choices

  18. Validation of simplified centre of mass models during gait in individuals with chronic stroke.

    Science.gov (United States)

    Huntley, Andrew H; Schinkel-Ivy, Alison; Aqui, Anthony; Mansfield, Avril

    2017-10-01

    The feasibility of using a multiple segment (full-body) kinematic model in clinical gait assessment is difficult when considering obstacles such as time and cost constraints. While simplified gait models have been explored in healthy individuals, no such work to date has been conducted in a stroke population. The aim of this study was to quantify the errors of simplified kinematic models for chronic stroke gait assessment. Sixteen individuals with chronic stroke (>6months), outfitted with full body kinematic markers, performed a series of gait trials. Three centre of mass models were computed: (i) 13-segment whole-body model, (ii) 3 segment head-trunk-pelvis model, and (iii) 1 segment pelvis model. Root mean squared error differences were compared between models, along with correlations to measures of stroke severity. Error differences revealed that, while both models were similar in the mediolateral direction, the head-trunk-pelvis model had less error in the anteroposterior direction and the pelvis model had less error in the vertical direction. There was some evidence that the head-trunk-pelvis model error is influenced in the mediolateral direction for individuals with more severe strokes, as a few significant correlations were observed between the head-trunk-pelvis model and measures of stroke severity. These findings demonstrate the utility and robustness of the pelvis model for clinical gait assessment in individuals with chronic stroke. Low error in the mediolateral and vertical directions is especially important when considering potential stability analyses during gait for this population, as lateral stability has been previously linked to fall risk. Copyright © 2017 Elsevier Ltd. All rights reserved.

  19. Alpha band frequency differences between low-trait and high-trait anxious individuals.

    Science.gov (United States)

    Ward, Richard T; Smith, Shelby L; Kraus, Brian T; Allen, Anna V; Moses, Michael A; Simon-Dack, Stephanie L

    2018-01-17

    Trait anxiety has been shown to cause significant impairments on attentional tasks. Current research has identified alpha band frequency differences between low-trait and high-trait anxious individuals. Here, we further investigated the underlying alpha band frequency differences between low-trait and high-trait anxious individuals during their resting state and the completion of an inhibition executive functioning task. Using human participants and quantitative electroencephalographic recordings, we measured alpha band frequency in individuals both high and low in trait anxiety during their resting state, and while they completed an Eriksen Flanker Task. Results indicated that high-trait anxious individuals exhibit a desynchronization in alpha band frequency from a resting state to when they complete the Eriksen Flanker Task. This suggests that high-trait anxious individuals maintain fewer attentional resources at rest and must martial resources for task performance as compared with low-trait anxious individuals, who appear to maintain stable cognitive resources between rest and task performance. These findings add to the cognitive neuroscience literature surrounding the role of alpha band frequency in low-trait and high-trait anxious individuals.

  20. Individual Differences in Dynamic Functional Brain Connectivity across the Human Lifespan.

    Directory of Open Access Journals (Sweden)

    Elizabeth N Davison

    2016-11-01

    Full Text Available Individual differences in brain functional networks may be related to complex personal identifiers, including health, age, and ability. Dynamic network theory has been used to identify properties of dynamic brain function from fMRI data, but the majority of analyses and findings remain at the level of the group. Here, we apply hypergraph analysis, a method from dynamic network theory, to quantify individual differences in brain functional dynamics. Using a summary metric derived from the hypergraph formalism-hypergraph cardinality-we investigate individual variations in two separate, complementary data sets. The first data set ("multi-task" consists of 77 individuals engaging in four consecutive cognitive tasks. We observe that hypergraph cardinality exhibits variation across individuals while remaining consistent within individuals between tasks; moreover, the analysis of one of the memory tasks revealed a marginally significant correspondence between hypergraph cardinality and age. This finding motivated a similar analysis of the second data set ("age-memory", in which 95 individuals, aged 18-75, performed a memory task with a similar structure to the multi-task memory task. With the increased age range in the age-memory data set, the correlation between hypergraph cardinality and age correspondence becomes significant. We discuss these results in the context of the well-known finding linking age with network structure, and suggest that hypergraph analysis should serve as a useful tool in furthering our understanding of the dynamic network structure of the brain.

  1. Discrete-time moment closure models for epidemic spreading in populations of interacting individuals.

    Science.gov (United States)

    Frasca, Mattia; Sharkey, Kieran J

    2016-06-21

    Understanding the dynamics of spread of infectious diseases between individuals is essential for forecasting the evolution of an epidemic outbreak or for defining intervention policies. The problem is addressed by many approaches including stochastic and deterministic models formulated at diverse scales (individuals, populations) and different levels of detail. Here we consider discrete-time SIR (susceptible-infectious-removed) dynamics propagated on contact networks. We derive a novel set of 'discrete-time moment equations' for the probability of the system states at the level of individual nodes and pairs of nodes. These equations form a set which we close by introducing appropriate approximations of the joint probabilities appearing in them. For the example case of SIR processes, we formulate two types of model, one assuming statistical independence at the level of individuals and one at the level of pairs. From the pair-based model we then derive a model at the level of the population which captures the behavior of epidemics on homogeneous random networks. With respect to their continuous-time counterparts, the models include a larger number of possible transitions from one state to another and joint probabilities with a larger number of individuals. The approach is validated through numerical simulation over different network topologies. Copyright © 2016 The Authors. Published by Elsevier Ltd.. All rights reserved.

  2. Individual Differences in Temporal Selective Attention as Reflected in Pupil Dilation

    OpenAIRE

    Willems, Charlotte; Herdzin, Johannes; Martens, Sander

    2015-01-01

    Background Attention is restricted for the second of two targets when it is presented within 200-500 ms of the first target. This attentional blink (AB) phenomenon allows one to study the dynamics of temporal selective attention by varying the interval between the two targets (T1 and T2). Whereas the AB has long been considered as a robust and universal cognitive limitation, several studies have demonstrated that AB task performance greatly differs between individuals, with some individuals s...

  3. Intertrial Variability in the Premotor Cortex Accounts for Individual Differences in Peripersonal Space.

    Science.gov (United States)

    Ferri, Francesca; Costantini, Marcello; Huang, Zirui; Perrucci, Mauro Gianni; Ferretti, Antonio; Romani, Gian Luca; Northoff, Georg

    2015-12-16

    We live in a dynamic environment, constantly confronted with approaching objects that we may either avoid or be forced to address. A multisensory and sensorimotor interface, the peripersonal space (PPS), mediates every physical interaction between our body and the environment. Behavioral investigations show high variability in the extension of PPS across individuals, but there is a lack of evidence on the neural underpinnings of these large individual differences. Here, we used approaching auditory stimuli and fMRI to capture the individual boundary of PPS and examine its neural underpinnings. Precisely, we tested the hypothesis that intertrial variability (ITV) in brain regions coding PPS predicts individual differences of its boundary at the behavioral level. Selectively in the premotor cortex, we found that ITV, rather than trial-averaged amplitude, of BOLD responses to far rather than near dynamic stimuli predicts the individual extension of PPS. Our results provide the first empirical support for the relevance of ITV of brain responses for individual differences in human behavior. Peripersonal space (PPS) is a multisensory and sensorimotor interface mediating every physical interaction between the body and the environment. A major characteristic of the boundary of PPS in humans is the extremely high variability of its location across individuals. We show that interindividual differences in the extension of the PPS are predicted by variability of BOLD responses in the premotor cortex to far stimuli approaching our body. Our results provide the first empirical support to the relevance of variability of evoked responses for human behavior and its variance across individuals. Copyright © 2015 the authors 0270-6474/15/3516328-12$15.00/0.

  4. Reliabilities of mental rotation tasks: limits to the assessment of individual differences.

    Science.gov (United States)

    Hirschfeld, Gerrit; Thielsch, Meinald T; Zernikow, Boris

    2013-01-01

    Mental rotation tasks with objects and body parts as targets are widely used in cognitive neuropsychology. Even though these tasks are well established to study between-groups differences, the reliability on an individual level is largely unknown. We present a systematic study on the internal consistency and test-retest reliability of individual differences in mental rotation tasks comparing different target types and orders of presentations. In total n = 99 participants (n = 63 for the retest) completed the mental rotation tasks with hands, feet, faces, and cars as targets. Different target types were presented in either randomly mixed blocks or blocks of homogeneous targets. Across all target types, the consistency (split-half reliability) and stability (test-retest reliabilities) were good or acceptable both for intercepts and slopes. At the level of individual targets, only intercepts showed acceptable reliabilities. Blocked presentations resulted in significantly faster and numerically more consistent and stable responses. Mental rotation tasks-especially in blocked variants-can be used to reliably assess individual differences in global processing speed. However, the assessment of the theoretically important slope parameter for individual targets requires further adaptations to mental rotation tests.

  5. An exploration of sensory and movement differences from the perspective of individuals with autism

    Directory of Open Access Journals (Sweden)

    Jodi eRobledo

    2012-11-01

    Full Text Available Parents, teachers, and people who themselves experience sensory and movement differences have consistently reported disturbances of sensation and movement associated with autism. Our review of the literature has revealed both historical and recent references to and research about sensory and movement difference characteristics and symptoms for individuals with autism. What is notably infrequent in this literature, however, is research that highlights the perspective of the individual with autism. If we wish to truly understand the experience of sensory and movement differences for individuals with autism, we must explore their experiences and perspectives. This study presents a qualitative analysis of more than 40 hours in-depth inquiry into the lives of five individuals with the autism label. Data were sorted into six categories: perception, action, posture, emotion, communication, and cognition. The insights into sensory and movement differences and autism offered by these individuals was illuminating. We found that the data strongly supported the presence of disruption of organization and regulation of sensory and movement differences in the lived experience of these participants with autism. The present data suggests that in autism this disruption of organization and regulation is amplified in terms of quantity, quality, intensity, and may affect everyday life. These data contribute to a more expansive view of autism that incorporates the possibility that autism is a disorder that affects motor planning, behavior, communication, the sensory motor system, and the dynamic interaction of all of these.

  6. Modeling heat stress under different environmental conditions.

    Science.gov (United States)

    Carabaño, M J; Logar, B; Bormann, J; Minet, J; Vanrobays, M-L; Díaz, C; Tychon, B; Gengler, N; Hammami, H

    2016-05-01

    Renewed interest in heat stress effects on livestock productivity derives from climate change, which is expected to increase temperatures and the frequency of extreme weather events. This study aimed at evaluating the effect of temperature and humidity on milk production in highly selected dairy cattle populations across 3 European regions differing in climate and production systems to detect differences and similarities that can be used to optimize heat stress (HS) effect modeling. Milk, fat, and protein test day data from official milk recording for 1999 to 2010 in 4 Holstein populations located in the Walloon Region of Belgium (BEL), Luxembourg (LUX), Slovenia (SLO), and southern Spain (SPA) were merged with temperature and humidity data provided by the state meteorological agencies. After merging, the number of test day records/cows per trait ranged from 686,726/49,655 in SLO to 1,982,047/136,746 in BEL. Values for the daily average and maximum temperature-humidity index (THIavg and THImax) ranges for THIavg/THImax were largest in SLO (22-74/28-84) and shortest in SPA (39-76/46-83). Change point techniques were used to determine comfort thresholds, which differed across traits and climatic regions. Milk yield showed an inverted U-shaped pattern of response across the THI scale with a HS threshold around 73 THImax units. For fat and protein, thresholds were lower than for milk yield and were shifted around 6 THI units toward larger values in SPA compared with the other countries. Fat showed lower HS thresholds than protein traits in all countries. The traditional broken line model was compared with quadratic and cubic fits of the pattern of response in production to increasing heat loads. A cubic polynomial model allowing for individual variation in patterns of response and THIavg as heat load measure showed the best statistical features. Higher/lower producing animals showed less/more persistent production (quantity and quality) across the THI scale. The

  7. Camouflage and individual variation in shore crabs (Carcinus maenas from different habitats.

    Directory of Open Access Journals (Sweden)

    Martin Stevens

    Full Text Available Camouflage is widespread throughout the natural world and conceals animals from predators in a vast range of habitats. Because successful camouflage usually involves matching aspects of the background environment, species and populations should evolve appearances tuned to their local habitat, termed phenotype-environment associations. However, although this has been studied in various species, little work has objectively quantified the appearances of camouflaged animals from different habitats, or related this to factors such as ontogeny and individual variation. Here, we tested for phenotype-environment associations in the common shore crab (Carcinus maenas, a species highly variable in appearance and found in a wide range of habitats. We used field surveys and digital image analysis of the colors and patterns of crabs found in four locations around Cornwall in the UK to quantify how individuals vary with habitat (predominantly rockpool, mussel bed, and mudflat. We find that individuals from sites comprising different backgrounds show substantial differences in several aspects of color and pattern, and that this is also dependent on life stage (adult or juvenile. Furthermore, the level of individual variation is dependent on site and life stage, with juvenile crabs often more variable than adults, and individuals from more homogenous habitats less diverse. Ours is the most comprehensive study to date exploring phenotype-environment associations for camouflage and individual variation in a species, and we discuss the implications of our results in terms of the mechanisms and selection pressures that may drive this.

  8. Psychosocial characteristics of adolescents with different profiles of individuation in relation to parents

    Directory of Open Access Journals (Sweden)

    Melita Puklek Levpušček

    2003-12-01

    Full Text Available Individuation in relation to parents represents an important developmental task during adolescence. The article focuses on the examination of different profiles of individuation in relation to parents and how these profiles manifest themselves in different periods of adolescence. We were also interested in the psychosocial characteristics that vary among adolescents with different profiles of individuation. The sample consisted of 593 adolescents in the age range of 13 to 18 years. The adolescents filled in the self-report questionnaires of individuation in relation to parents and friends, perceived parental behavior, and perceived self-efficacy in learning. They also reported about the frequency of psychological symptoms experienced in the last month. To identify the diverse groups of adolescents the scores on the scale of individuation in relation to parents were subjected to a cluster analysis. Finally, the four-cluster solution was chosen. The clusters were named: Good connectedness with parents with non-threatened autonomy, Highly harmonious relationship with parents with non-threatened autonomy, Cold relationship with parents with threatened autonomy and Ambivalent relationship with parents. The results confirmed the hypothesis, that most adolescents will be classified in the profiles of good relationship with parents with non-threatened autonomy. The results also showed that the combination of moderate emotional connectedness with parents, low parental idealization, ability to integrate autonomy and connectedness, low denial of dependency needs and low engulfment anxiety represent the most favorable individuation pattern for psychological adaptation of adolescents.

  9. Different Roles of Direct and Indirect Frontoparietal Pathways for Individual Working Memory Capacity.

    Science.gov (United States)

    Ekman, Matthias; Fiebach, Christian J; Melzer, Corina; Tittgemeyer, Marc; Derrfuss, Jan

    2016-03-09

    The ability to temporarily store and manipulate information in working memory is a hallmark of human intelligence and differs considerably across individuals, but the structural brain correlates underlying these differences in working memory capacity (WMC) are only poorly understood. In two separate studies, diffusion MRI data and WMC scores were collected for 70 and 109 healthy individuals. Using a combination of probabilistic tractography and network analysis of the white matter tracts, we examined whether structural brain network properties were predictive of individual WMC. Converging evidence from both studies showed that lateral prefrontal cortex and posterior parietal cortex of high-capacity individuals are more densely connected compared with low-capacity individuals. Importantly, our network approach was further able to dissociate putative functional roles associated with two different pathways connecting frontal and parietal regions: a corticocortical pathway and a subcortical pathway. In Study 1, where participants were required to maintain and update working memory items, the connectivity of the direct and indirect pathway was predictive of WMC. In contrast, in Study 2, where participants were required to maintain working memory items without updating, only the connectivity of the direct pathway was predictive of individual WMC. Our results suggest an important dissociation in the circuitry connecting frontal and parietal regions, where direct frontoparietal connections might support storage and maintenance, whereas subcortically mediated connections support the flexible updating of working memory content. Copyright © 2016 the authors 0270-6474/16/362894-10$15.00/0.

  10. Individual differences in posterior cortical volume correlate with proneness to pride and gratitude.

    Science.gov (United States)

    Zahn, Roland; Garrido, Griselda; Moll, Jorge; Grafman, Jordan

    2014-11-01

    Proneness to specific moral sentiments (e.g. pride, gratitude, guilt, indignation) has been linked with individual variations in functional MRI (fMRI) response within anterior brain regions whose lesion leads to inappropriate behaviour. However, the role of structural anatomical differences in rendering individuals prone to particular moral sentiments relative to others is unknown. Here, we investigated grey matter volumes (VBM8) and proneness to specific moral sentiments on a well-controlled experimental task in healthy individuals. Individuals with smaller cuneus, and precuneus volumes were more pride-prone, whereas those with larger right inferior temporal volumes experienced gratitude more readily. Although the primary analysis detected no associations with guilt- or indignation-proneness, subgenual cingulate fMRI responses to guilt were negatively correlated with grey matter volumes in the left superior temporal sulcus and anterior dorsolateral prefrontal cortices (right >left). This shows that individual variations in functional activations within critical areas for moral sentiments were not due to grey matter volume differences in the same areas. Grey matter volume differences between healthy individuals may nevertheless play an important role by affecting posterior cortical brain systems that are non-critical but supportive for the experience of specific moral sentiments. This may be of particular relevance when their experience depends on visuo-spatial elaboration. Published by Oxford University Press 2013. This work is written by US Government employees and is in the public domain in the US.

  11. Camouflage and individual variation in shore crabs (Carcinus maenas) from different habitats.

    Science.gov (United States)

    Stevens, Martin; Lown, Alice E; Wood, Louisa E

    2014-01-01

    Camouflage is widespread throughout the natural world and conceals animals from predators in a vast range of habitats. Because successful camouflage usually involves matching aspects of the background environment, species and populations should evolve appearances tuned to their local habitat, termed phenotype-environment associations. However, although this has been studied in various species, little work has objectively quantified the appearances of camouflaged animals from different habitats, or related this to factors such as ontogeny and individual variation. Here, we tested for phenotype-environment associations in the common shore crab (Carcinus maenas), a species highly variable in appearance and found in a wide range of habitats. We used field surveys and digital image analysis of the colors and patterns of crabs found in four locations around Cornwall in the UK to quantify how individuals vary with habitat (predominantly rockpool, mussel bed, and mudflat). We find that individuals from sites comprising different backgrounds show substantial differences in several aspects of color and pattern, and that this is also dependent on life stage (adult or juvenile). Furthermore, the level of individual variation is dependent on site and life stage, with juvenile crabs often more variable than adults, and individuals from more homogenous habitats less diverse. Ours is the most comprehensive study to date exploring phenotype-environment associations for camouflage and individual variation in a species, and we discuss the implications of our results in terms of the mechanisms and selection pressures that may drive this.

  12. Investigating DIF and extensions using an LLTM approach and also an individual differences approach: an international testing context

    Directory of Open Access Journals (Sweden)

    YIYU XIE

    2008-09-01

    Full Text Available This study intends to investigate two ways to generalise differential item functioning (DIF by grouping of items that share a common feature, or an item property as in the Linear Logistic Test Model (LLTM. An item “facet” refers to this type of grouping, and DIF can be expressed in terms of more fundamental parameters that relate to the facet of items. Hence the differential facet functioning (DFF model, a particular version of the LLTM, helps to explain the DIF effects more substantively. Using the mathematics data from the Program for International Student Assessment (PISA 2003, this study shows that modeling the DFF effect through an interaction of the group-by-facet parameter rather than DIF effect on the individual item level can be handled easily with the NLMIXED procedure of SAS. We found that the results are more interpretable when the bias is interpreted on the facet level rather than the item level. Analogous to the multidimensional DIF model, one natural extension of the DFF model is to make the model multidimensional when DFF facets (i.e., LLTM facets are considered as dimensions. This extension, multidimensional DFF (MDFF, is also investigated. The MDFF model allows individual differences to be modeled on the dimension that exhibits a DFF effect. However, it is always recommended to check the individual DIF estimates and construct a substantive analysis first before conducting DFF and MDFF analysis.

  13. Neural loss aversion differences between depression patients and healthy individuals: A functional MRI investigation.

    Science.gov (United States)

    Chandrasekhar Pammi, V S; Pillai Geethabhavan Rajesh, Purushothaman; Kesavadas, Chandrasekharan; Rappai Mary, Paramban; Seema, Satish; Radhakrishnan, Ashalatha; Sitaram, Ranganatha

    2015-04-01

    Neuroeconomics employs neuroscience techniques to explain decision-making behaviours. Prospect theory, a prominent model of decision-making, features a value function with parameters for risk and loss aversion. Recent work with normal participants identified activation related to loss aversion in brain regions including the amygdala, ventral striatum, and ventromedial prefrontal cortex. However, the brain network for loss aversion in pathologies such as depression has yet to be identified. The aim of the current study is to employ the value function from prospect theory to examine behavioural and neural manifestations of loss aversion in depressed and healthy individuals to identify the neurobiological markers of loss aversion in economic behaviour. We acquired behavioural data and fMRI scans while healthy controls and patients with depression performed an economic decision-making task. Behavioural loss aversion was higher in patients with depression than in healthy controls. fMRI results revealed that the two groups shared a brain network for value function including right ventral striatum, ventromedial prefrontal cortex, and right amygdala. However, the neural loss aversion results revealed greater activations in the right dorsal striatum and the right anterior insula for controls compared with patients with depression, and higher activations in the midbrain region ventral tegmental area for patients with depression compared with controls. These results suggest that while the brain network for loss aversion is shared between depressed and healthy individuals, some differences exist with respect to differential activation of additional areas. Our findings are relevant to identifying neurobiological markers for altered decision-making in the depressed. © The Author(s) 2015 Reprints and permissions: sagepub.co.uk/journalsPermissions.nav.

  14. Do individual females differ intrinsically in their propensity to engage in extra-pair copulations?

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    Wolfgang Forstmeier

    Full Text Available BACKGROUND: While many studies have investigated the occurrence of extra-pair paternity in wild populations of birds, we still know surprisingly little about whether individual females differ intrinsically in their principal readiness to copulate, and to what extent this readiness is affected by male attractiveness. METHODOLOGY/FINDINGS: To address this question I used captive zebra finches (Taeniopygia guttata as a model system. I first measured female readiness to copulate when courted by a male for the first time in life. Second, I conducted choice-chamber experiments to assess the mating preferences of individual females prior to pair formation. I then paired females socially with a non-desired mate and once they had formed a stable pair bond, I observed the inclination of these females to engage in extra-pair copulations with various males. Females showing a high readiness to copulate when courted by a male for the first time in life were much more likely to engage in extra-pair copulations later in life than others. Male attractiveness, as measured in choice tests, was a useful predictor of whether females engaged in extra-pair copulations with these males, but, surprisingly, the attractiveness of a female's social partner had no effect on her fidelity. However, it remained unclear what made some males more attractive than others. Contrary to a widespread but rarely tested hypothesis, females did not preferentially copulate with males having a redder beak or singing at a higher rate. Rather it seemed that song rate was a confounding factor in choice-chamber experiments: song attracted the female's attention but did not increase the male's attractiveness as a copulation partner. CONCLUSIONS/SIGNIFICANCE: Intrinsic variation in female readiness to copulate as well as variation in the attractiveness of the extra-pair male but not the social partner decided the outcome of extra-pair encounters.

  15. Individual differences in memory span: the contribution of rehearsal, access to lexical memory, and output speed.

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    Tehan, G; Lalor, D M

    2000-11-01

    Rehearsal speed has traditionally been seen to be the prime determinant of individual differences in memory span. Recent studies, in the main using young children as the subject population, have suggested other contributors to span performance, notably contributions from long-term memory and forgetting and retrieval processes occurring during recall. In the current research we explore individual differences in span with respect to measures of rehearsal, output time, and access to lexical memory. We replicate standard short-term phenomena; we show that the variables that influence children's span performance influence adult performance in the same way; and we show that lexical memory access appears to be a more potent source of individual differences in span than either rehearsal speed or output factors.

  16. Genomic tools for behavioural ecologists to understand repeatable individual differences in behaviour.

    Science.gov (United States)

    Bengston, Sarah E; Dahan, Romain A; Donaldson, Zoe; Phelps, Steven M; van Oers, Kees; Sih, Andrew; Bell, Alison M

    2018-06-01

    Behaviour is a key interface between an animal's genome and its environment. Repeatable individual differences in behaviour have been extensively documented in animals, but the molecular underpinnings of behavioural variation among individuals within natural populations remain largely unknown. Here, we offer a critical review of when molecular techniques may yield new insights, and we provide specific guidance on how and whether the latest tools available are appropriate given different resources, system and organismal constraints, and experimental designs. Integrating molecular genetic techniques with other strategies to study the proximal causes of behaviour provides opportunities to expand rapidly into new avenues of exploration. Such endeavours will enable us to better understand how repeatable individual differences in behaviour have evolved, how they are expressed and how they can be maintained within natural populations of animals.

  17. Steady States in SIRS Epidemical Model of Mobile Individuals

    International Nuclear Information System (INIS)

    Zhang Duanming; He Minhua; Yu Xiaoling; Pan Guijun; Sun Hongzhang; Su Xiangying; Sun Fan; Yin Yanping; Li Rui; Liu Dan

    2006-01-01

    We consider an epidemical model within socially interacting mobile individuals to study the behaviors of steady states of epidemic propagation in 2D networks. Using mean-field approximation and large scale simulations, we recover the usual epidemic behavior with critical thresholds δ c and p c below which infectious disease dies out. For the population density δ far above δ c , it is found that there is linear relationship between contact rate λ and the population density δ in the main. At the same time, the result obtained from mean-field approximation is compared with our numerical result, and it is found that these two results are similar by and large but not completely the same.

  18. Steady States in SIRS Epidemical Model of Mobile Individuals

    Institute of Scientific and Technical Information of China (English)

    ZHANG Duan-Ming; LIU Dan; HE Min-Hua; YU Xiao-Ling; PAN Gui-Jun; SUN Hong-Zhang; SU Xiang-Ying; SUN Fan; YIN Yan-Ping; LI Rui

    2006-01-01

    We consider an epidemical model within socially interacting mobile individuals to study the behaviors of steady statesof epidemic propagation in 2D networks. Using mean-field approximation and large scale simulations, we recover the usual epidemic behavior with critical thresholds δc and pc below which infectious disease dies out. For the population density δ far above δc, it is found that there is linear relationship between contact rate λ and the population density δ in the main. At the same time, the result obtained from mean-field approximation is compared with our numerical result, and it is found that these two results are similar by and large but not completely the same.

  19. A model of individualized canonical microcircuits supporting cognitive operations.

    Directory of Open Access Journals (Sweden)

    Tim Kunze

    Full Text Available Major cognitive functions such as language, memory, and decision-making are thought to rely on distributed networks of a large number of basic elements, called canonical microcircuits. In this theoretical study we propose a novel canonical microcircuit model and find that it supports two basic computational operations: a gating mechanism and working memory. By means of bifurcation analysis we systematically investigate the dynamical behavior of the canonical microcircuit with respect to parameters that govern the local network balance, that is, the relationship between excitation and inhibition, and key intrinsic feedback architectures of canonical microcircuits. We relate the local behavior of the canonical microcircuit to cognitive processing and demonstrate how a network of interacting canonical microcircuits enables the establishment of spatiotemporal sequences in the context of syntax parsing during sentence comprehension. This study provides a framework for using individualized canonical microcircuits for the construction of biologically realistic networks supporting cognitive operations.

  20. Modelling and modal properties of the railway vehicle bogie with two individual wheelset drives

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    Zeman V.

    2007-10-01

    Full Text Available The paper deals with mathematical modelling of vibration and modal analysis of two-axled bogie of a railway vehicle. In comparison with recent publications introducing mathematical models of an individual wheelset drive, this paper is focused on modelling of complex bogie vibration. The bogie frame is linked by primary suspension to the two wheelset drives with hollow shafts and by secondary suspension to the car body. The method is based on the system decomposition into three subsystems – two individual wheelset drives including the mass of the rail and the bogie frame coupled with a half of the car body – and on modelling of couplings among subsystems. The eigenvalues of a linearized autonomous model and stability conditions are investigated in dependence on longitudinal creepage and forward velocity of the railway vehicle. The nonlinear model will be used for investigating the dynamic loading of bogie components caused by different types of excitation.

  1. A connectionist model of category learning by individuals with high-functioning autism spectrum disorder.

    Science.gov (United States)

    Dovgopoly, Alexander; Mercado, Eduardo

    2013-06-01

    Individuals with autism spectrum disorder (ASD) show atypical patterns of learning and generalization. We explored the possible impacts of autism-related neural abnormalities on perceptual category learning using a neural network model of visual cortical processing. When applied to experiments in which children or adults were trained to classify complex two-dimensional images, the model can account for atypical patterns of perceptual generalization. This is only possible, however, when individual differences in learning are taken into account. In particular, analyses performed with a self-organizing map suggested that individuals with high-functioning ASD show two distinct generalization patterns: one that is comparable to typical patterns, and a second in which there is almost no generalization. The model leads to novel predictions about how individuals will generalize when trained with simplified input sets and can explain why some researchers have failed to detect learning or generalization deficits in prior studies of category learning by individuals with autism. On the basis of these simulations, we propose that deficits in basic neural plasticity mechanisms may be sufficient to account for the atypical patterns of perceptual category learning and generalization associated with autism, but they do not account for why only a subset of individuals with autism would show such deficits. If variations in performance across subgroups reflect heterogeneous neural abnormalities, then future behavioral and neuroimaging studies of individuals with ASD will need to account for such disparities.

  2. Continuous time modelling with individually varying time intervals for oscillating and non-oscillating processes.

    Science.gov (United States)

    Voelkle, Manuel C; Oud, Johan H L

    2013-02-01

    When designing longitudinal studies, researchers often aim at equal intervals. In practice, however, this goal is hardly ever met, with different time intervals between assessment waves and different time intervals between individuals being more the rule than the exception. One of the reasons for the introduction of continuous time models by means of structural equation modelling has been to deal with irregularly spaced assessment waves (e.g., Oud & Delsing, 2010). In the present paper we extend the approach to individually varying time intervals for oscillating and non-oscillating processes. In addition, we show not only that equal intervals are unnecessary but also that it can be advantageous to use unequal sampling intervals, in particular when the sampling rate is low. Two examples are provided to support our arguments. In the first example we compare a continuous time model of a bivariate coupled process with varying time intervals to a standard discrete time model to illustrate the importance of accounting for the exact time intervals. In the second example the effect of different sampling intervals on estimating a damped linear oscillator is investigated by means of a Monte Carlo simulation. We conclude that it is important to account for individually varying time intervals, and encourage researchers to conceive of longitudinal studies with different time intervals within and between individuals as an opportunity rather than a problem. © 2012 The British Psychological Society.

  3. Driving-forces model on individual behavior in scenarios considering moving threat agents

    Science.gov (United States)

    Li, Shuying; Zhuang, Jun; Shen, Shifei; Wang, Jia

    2017-09-01

    The individual behavior model is a contributory factor to improve the accuracy of agent-based simulation in different scenarios. However, few studies have considered moving threat agents, which often occur in terrorist attacks caused by attackers with close-range weapons (e.g., sword, stick). At the same time, many existing behavior models lack validation from cases or experiments. This paper builds a new individual behavior model based on seven behavioral hypotheses. The driving-forces model is an extension of the classical social force model considering scenarios including moving threat agents. An experiment was conducted to validate the key components of the model. Then the model is compared with an advanced Elliptical Specification II social force model, by calculating the fitting errors between the simulated and experimental trajectories, and being applied to simulate a specific circumstance. Our results show that the driving-forces model reduced the fitting error by an average of 33.9% and the standard deviation by an average of 44.5%, which indicates the accuracy and stability of the model in the studied situation. The new driving-forces model could be used to simulate individual behavior when analyzing the risk of specific scenarios using agent-based simulation methods, such as risk analysis of close-range terrorist attacks in public places.

  4. Individual differences in non-verbal number acuity correlate with maths achievement.

    Science.gov (United States)

    Halberda, Justin; Mazzocco, Michèle M M; Feigenson, Lisa

    2008-10-02

    Human mathematical competence emerges from two representational systems. Competence in some domains of mathematics, such as calculus, relies on symbolic representations that are unique to humans who have undergone explicit teaching. More basic numerical intuitions are supported by an evolutionarily ancient approximate number system that is shared by adults, infants and non-human animals-these groups can all represent the approximate number of items in visual or auditory arrays without verbally counting, and use this capacity to guide everyday behaviour such as foraging. Despite the widespread nature of the approximate number system both across species and across development, it is not known whether some individuals have a more precise non-verbal 'number sense' than others. Furthermore, the extent to which this system interfaces with the formal, symbolic maths abilities that humans acquire by explicit instruction remains unknown. Here we show that there are large individual differences in the non-verbal approximation abilities of 14-year-old children, and that these individual differences in the present correlate with children's past scores on standardized maths achievement tests, extending all the way back to kindergarten. Moreover, this correlation remains significant when controlling for individual differences in other cognitive and performance factors. Our results show that individual differences in achievement in school mathematics are related to individual differences in the acuity of an evolutionarily ancient, unlearned approximate number sense. Further research will determine whether early differences in number sense acuity affect later maths learning, whether maths education enhances number sense acuity, and the extent to which tertiary factors can affect both.

  5. Revisiting the impact of job satisfaction and organizational commitment on nurse turnover intention: an individual differences analysis.

    Science.gov (United States)

    De Gieter, Sara; Hofmans, Joeri; Pepermans, Roland

    2011-12-01

    Nurse turnover is an important contributing factor to the worldwide nursing shortage. Many studies have examined the antecedents of nurse turnover to gain a better understanding of the problem and help hospitals reduce their turnover rates. However, an important shortcoming of this research stream is its exclusive focus on explaining turnover behavior of the "average nurse", thereby disregarding individual differences between nurses and groups of nurses. To examine individual differences in the relationships between two crucial turnover antecedents - job satisfaction and organizational commitment - and nurse turnover intention. A sample of 287 nurses working for a variety of Belgian hospitals participated in the study. A survey method was used to collect quantitative data, which were analyzed through standard multiple linear regression, mixture regression models and t-tests. In the total sample of hospital nurses, both job satisfaction and organizational commitment significantly predicted nurse turnover intention. However, subsequent individual differences analyses revealed the existence of two subgroups of nurses. In the satisfaction focused group, only job satisfaction was found to predict nurse turnover intention, whereas in the satisfaction and commitment focused group both job satisfaction and organizational commitment were related to turnover intention. Furthermore, nurses in the latter group displayed stronger turnover intention, were significantly younger and had less job tenure and organizational tenure than nurses in the satisfaction focused group. The debate on the antecedents of nurse turnover still continues, as the existing models fail to fully grasp nurse turnover. The present study identifies individual differences in nurse turnover antecedents among groups of nurses as a possible reason for the absence of one comprehensive turnover model that holds for the general nursing population. Further studies are needed in order to capture the total impact

  6. Beyond Self-Report: Emerging Methods for Capturing Individual Differences in Decision-Making Process

    Directory of Open Access Journals (Sweden)

    Brenda L Connors

    2016-03-01

    Full Text Available People vary in the way in which they approach decision making, which impacts real-world behavior. There has been a surge of interest in moving beyond reliance on self-report measures to capture such individual differences. Particular emphasis has been placed on devising and applying a range of methodologies that include experimental, neuroscience, and observational paradigms. This paper provides a selective review of recent studies that illustrate the methods and yield of these approaches in terms of generating a deeper understanding of decision-making style and the notable differences that can be found across individuals.

  7. Examining regional variability in work ethic within Mexico: Individual difference or shared value.

    Science.gov (United States)

    Arciniega, Luis M; Woehr, David J; Del Rincón, Germán A

    2018-02-19

    Despite the acceptance of work ethic as an important individual difference, little research has examined the extent to which work ethic may reflect shared environmental or socio-economic factors. This research addresses this concern by examining the influence of geographic proximity on the work ethic experienced by 254 employees from Mexico, working in 11 different cities in the Northern, Central and Southern regions of the country. Using a sequence of complementary analyses to assess the main source of variance on seven dimensions of work ethic, our results indicate that work ethic is most appropriately considered at the individual level. © 2018 International Union of Psychological Science.

  8. Educational Barriers of Rural Youth: Relation of Individual and Contextual Difference Variables

    Science.gov (United States)

    Irvin, Matthew J.; Byun, Soo-yong; Meece, Judith L.; Farmer, Thomas W.

    2014-01-01

    The purpose of this study was to examine the relation of several individual and contextual difference factors to the perceived educational barriers of rural youth. Data were from a broader national investigation of students’ postsecondary aspirations and preparation in rural high schools across the United States. The sample involved more than 7,000 rural youth in 73 high schools across 34 states. Results indicated that some individual (e.g., African American race/ethnicity) and contextual (e.g., parent education) difference factors were predictive while others were not. Extensions to, similarities, and variations with previous research are discussed. Implications, limitations, and suggestions for future research are also discussed. PMID:24474843

  9. Who takes the most revenge? Individual differences in negative reciprocity norm endorsement.

    Science.gov (United States)

    Eisenberger, Robert; Lynch, Patrick; Aselage, Justin; Rohdieck, Stephanie

    2004-06-01

    The authors report that beliefs favoring the reciprocation of unfavorable treatment form a unitary factor that is distinct from beliefs favoring the reciprocation of favorable treatment. Individual differences in endorsement of this negative reciprocity norm were related to (a) beliefs that people are generally malevolent; (b) inclination toward anger in everyday life; (c) anger, disagreement, and ridicule directed toward a new acquaintance who treated participants unfavorably; and (d) reduced anxiety, positive emotional engagement, and encouragement of a new acquaintance who treated participants favorably. These findings suggest that individual differences in endorsement of the negative norm of reciprocity influence the extent of vengeance.

  10. Comparing flood loss models of different complexity

    Science.gov (United States)

    Schröter, Kai; Kreibich, Heidi; Vogel, Kristin; Riggelsen, Carsten; Scherbaum, Frank; Merz, Bruno

    2013-04-01

    Any deliberation on flood risk requires the consideration of potential flood losses. In particular, reliable flood loss models are needed to evaluate cost-effectiveness of mitigation measures, to assess vulnerability, for comparative risk analysis and financial appraisal during and after floods. In recent years, considerable improvements have been made both concerning the data basis and the methodological approaches used for the development of flood loss models. Despite of that, flood loss models remain an important source of uncertainty. Likewise the temporal and spatial transferability of flood loss models is still limited. This contribution investigates the predictive capability of different flood loss models in a split sample cross regional validation approach. For this purpose, flood loss models of different complexity, i.e. based on different numbers of explaining variables, are learned from a set of damage records that was obtained from a survey after the Elbe flood in 2002. The validation of model predictions is carried out for different flood events in the Elbe and Danube river basins in 2002, 2005 and 2006 for which damage records are available from surveys after the flood events. The models investigated are a stage-damage model, the rule based model FLEMOps+r as well as novel model approaches which are derived using data mining techniques of regression trees and Bayesian networks. The Bayesian network approach to flood loss modelling provides attractive additional information concerning the probability distribution of both model predictions and explaining variables.

  11. Individualization of psychological training and its importance at different stages of many years’ perfection in tennis

    Directory of Open Access Journals (Sweden)

    N.L. Vysochina

    2015-08-01

    Full Text Available Purpose: to determine significance of individualized approach during psychological training at different stages of many years’ perfection in tennis. The tasks of the research were studying of place and role of psychological component in general system of tennis players’ sport training as well as determination of specificities of individualized approach during 14-15 years old and elite tennis players’ psychological training. Material: In the research 24 experts, coaches of combined teams and clubs, elite tennis players took part. Results: Role of psychological training in general system of many years’ perfection has been determined. We also found out that individualization of psychological training in modern tennis is not paid sufficient attention to at present. Most of the questioned respondents pointed, that such training is conducted mainly with elite sportsmen (42%. Only 14% noted that individual psychological training is carried out at basic stages of many years’ perfection. Conclusions: Principle of individualization is a determining one in the course of sportsmen’s training at stages of many years’ perfection. About 86% of experts stressed on significance of application of individualized approach in work with tennis players. Consideration of tennis players’ individual features during psychological training is a compulsory matter in increasing of effectiveness of sportsmen’s training and competition functioning.

  12. Testing problem-solving capacities: differences between individual testing and social group setting.

    Science.gov (United States)

    Krasheninnikova, Anastasia; Schneider, Jutta M

    2014-09-01

    Testing animals individually in problem-solving tasks limits distractions of the subjects during the test, so that they can fully concentrate on the problem. However, such individual performance may not indicate the problem-solving capacity that is commonly employed in the wild when individuals are faced with a novel problem in their social groups, where the presence of a conspecific influences an individual's behaviour. To assess the validity of data gathered from parrots when tested individually, we compared the performance on patterned-string tasks among parrots tested singly and parrots tested in social context. We tested two captive groups of orange-winged amazons (Amazona amazonica) with several patterned-string tasks. Despite the differences in the testing environment (singly vs. social context), parrots from both groups performed similarly. However, we found that the willingness to participate in the tasks was significantly higher for the individuals tested in social context. The study provides further evidence for the crucial influence of social context on individual's response to a challenging situation such as a problem-solving test.

  13. Comparing estimates of genetic variance across different relationship models.

    Science.gov (United States)

    Legarra, Andres

    2016-02-01

    Use of relationships between individuals to estimate genetic variances and heritabilities via mixed models is standard practice in human, plant and livestock genetics. Different models or information for relationships may give different estimates of genetic variances. However, comparing these estimates across different relationship models is not straightforward as the implied base populations differ between relationship models. In this work, I present a method to compare estimates of variance components across different relationship models. I suggest referring genetic variances obtained using different relationship models to the same reference population, usually a set of individuals in the population. Expected genetic variance of this population is the estimated variance component from the mixed model times a statistic, Dk, which is the average self-relationship minus the average (self- and across-) relationship. For most typical models of relationships, Dk is close to 1. However, this is not true for very deep pedigrees, for identity-by-state relationships, or for non-parametric kernels, which tend to overestimate the genetic variance and the heritability. Using mice data, I show that heritabilities from identity-by-state and kernel-based relationships are overestimated. Weighting these estimates by Dk scales them to a base comparable to genomic or pedigree relationships, avoiding wrong comparisons, for instance, "missing heritabilities". Copyright © 2015 Elsevier Inc. All rights reserved.

  14. The causes of variation in learning and behavior: Why individual differences matter

    Directory of Open Access Journals (Sweden)

    Bruno eSauce

    2013-07-01

    Full Text Available In a seminal paper written five decades ago, Cronbach discussed the two highly distinct approaches to scientific psychology: experimental and correlational. Today, although these two approaches are fruitfully implemented and embraced across some fields of psychology, this synergy is largely absent from other areas, such as in the study of learning and behavior. Both Tolman and Hull, in a rare case of agreement, stated that the correlational approach held little promise for the understanding of behavior. Interestingly, this dismissal of the study of individual differences was absent in the biologically-oriented branches of behavior analysis, namely, behavioral genetics and ethology. Here we propose that the distinction between causation and causes of variation (with its origins in the field of genetics reveal the potential value of the correlational approach in understanding the full complexity of learning and behavior. Although the experimental approach can illuminate the causal variables that modulate learning, the analysis of individual differences can elucidate how much and in which way variables interact to support variations in learning in complex natural environments. For example, understanding that a past experience with a stimulus influences its associability provides little insight into how individual predispositions interact to modulate this influence on associability. In this new light, we discuss examples from studies of individual differences in animals’ performance in the Morris Water Maze and from our own work on individual differences in general intelligence in mice. These studies illustrate that, opposed to what Underwood famously suggested, studies of individual differences can do much more to psychology than merely providing preliminary indications of cause-effect relationships.

  15. Do people essentialize emotions? Individual differences in emotion essentialism and emotional experience.

    Science.gov (United States)

    Lindquist, Kristen A; Gendron, Maria; Oosterwijk, Suzanne; Barrett, Lisa Feldman

    2013-08-01

    Many scientific models of emotion assume that emotion categories are natural kinds that carve nature at its joints. These beliefs remain strong, despite the fact that the empirical record on the issue has remained equivocal for over a century. In this research, the authors examined one reason for this situation: People essentialize emotion categories by assuming that members of the same category (e.g., fear) have a shared metaphysical essence (i.e., a common causal mechanism). In Study 1, the authors found that lay people essentialize emotions by assuming that instances of the same emotion category have a shared essence that defines them, even when their surface features differ. Study 2 extended these findings, demonstrating that lay people tend to essentialize categories the more a category is of the body (vs. the mind). In Study 3, we examined the links between emotion essentialism and the complexity of actual emotional experiences. In particular, we predicted and found that individuals who hold essentialist beliefs about emotions describe themselves as experiencing highly differentiated emotional experiences but do not show evidence of stronger emotional differentiation in their momentary ratings of experience in everyday life. Implications for the science of emotion are discussed. PsycINFO Database Record (c) 2013 APA, all rights reserved.

  16. Measuring total health inequality: adding individual variation to group-level differences

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    Gakidou Emmanuela

    2002-08-01

    Full Text Available Abstract Background Studies have revealed large variations in average health status across social, economic, and other groups. No study exists on the distribution of the risk of ill-health across individuals, either within groups or across all people in a society, and as such a crucial piece of total health inequality has been overlooked. Some of the reason for this neglect has been that the risk of death, which forms the basis for most measures, is impossible to observe directly and difficult to estimate. Methods We develop a measure of total health inequality – encompassing all inequalities among people in a society, including variation between and within groups – by adapting a beta-binomial regression model. We apply it to children under age two in 50 low- and middle-income countries. Our method has been adopted by the World Health Organization and is being implemented in surveys around the world; preliminary estimates have appeared in the World Health Report (2000. Results Countries with similar average child mortality differ considerably in total health inequality. Liberia and Mozambique have the largest inequalities in child survival, while Colombia, the Philippines and Kazakhstan have the lowest levels among the countries measured. Conclusions Total health inequality estimates should be routinely reported alongside average levels of health in populations and groups, as they reveal important policy-related information not otherwise knowable. This approach enables meaningful comparisons of inequality across countries and future analyses of the determinants of inequality.

  17. Quantifying sleep architecture dynamics and individual differences using big data and Bayesian networks.

    Science.gov (United States)

    Yetton, Benjamin D; McDevitt, Elizabeth A; Cellini, Nicola; Shelton, Christian; Mednick, Sara C

    2018-01-01

    The pattern of sleep stages across a night (sleep architecture) is influenced by biological, behavioral, and clinical variables. However, traditional measures of sleep architecture such as stage proportions, fail to capture sleep dynamics. Here we quantify the impact of individual differences on the dynamics of sleep architecture and determine which factors or set of factors best predict the next sleep stage from current stage information. We investigated the influence of age, sex, body mass index, time of day, and sleep time on static (e.g. minutes in stage, sleep efficiency) and dynamic measures of sleep architecture (e.g. transition probabilities and stage duration distributions) using a large dataset of 3202 nights from a non-clinical population. Multi-level regressions show that sex effects duration of all Non-Rapid Eye Movement (NREM) stages, and age has a curvilinear relationship for Wake After Sleep Onset (WASO) and slow wave sleep (SWS) minutes. Bayesian network modeling reveals sleep architecture depends on time of day, total sleep time, age and sex, but not BMI. Older adults, and particularly males, have shorter bouts (more fragmentation) of Stage 2, SWS, and they transition less frequently to these stages. Additionally, we showed that the next sleep stage and its duration can be optimally predicted by the prior 2 stages and age. Our results demonstrate the potential benefit of big data and Bayesian network approaches in quantifying static and dynamic architecture of normal sleep.

  18. Individual differences in ideological attitudes and prejudice: evidence from peer-report data.

    Science.gov (United States)

    Cohrs, J Christopher; Kämpfe-Hargrave, Nicole; Riemann, Rainer

    2012-08-01

    Our knowledge on the personality basis of ideological attitudes and prejudice, while based on a substantial body of research, suffers from a potentially serious methodological limitation: an overreliance on the method of self-reports. Across 2 studies (Ns = 193, 424), we examined associations between the Big Five personality dimensions, Right-Wing Authoritarianism (RWA), Social Dominance Orientation (SDO), and generalized prejudice, using both self-report and peer-report data stemming from 1 (Study 1) or 2 (Study 2) peer rater/s. Correlational and regression analyses as well as structural equation modeling showed that (a) the associations between personality dimensions, ideological attitudes, and prejudice were largely similar to previous research for both data sources; (b) RWA and prejudice showed a similar level of self-peer agreement to personality dimensions; (c) most of the known associations between personality, ideological attitudes, and prejudice were replicated also when measured by independent methods; (d) peer reports had some incremental validity in predicting ideological attitudes and prejudice; and (e) there was evidence that Openness to Experience and Agreeableness predicted prejudice directly and not only indirectly via RWA and SDO, respectively. Implications for the status of RWA, SDO, and prejudice as individual-difference constructs and for their bases in personality dimensions are discussed.

  19. Individual differences in language and working memory affect children's speech recognition in noise.

    Science.gov (United States)

    McCreery, Ryan W; Spratford, Meredith; Kirby, Benjamin; Brennan, Marc

    2017-05-01

    We examined how cognitive and linguistic skills affect speech recognition in noise for children with normal hearing. Children with better working memory and language abilities were expected to have better speech recognition in noise than peers with poorer skills in these domains. As part of a prospective, cross-sectional study, children with normal hearing completed speech recognition in noise for three types of stimuli: (1) monosyllabic words, (2) syntactically correct but semantically anomalous sentences and (3) semantically and syntactically anomalous word sequences. Measures of vocabulary, syntax and working memory were used to predict individual differences in speech recognition in noise. Ninety-six children with normal hearing, who were between 5 and 12 years of age. Higher working memory was associated with better speech recognition in noise for all three stimulus types. Higher vocabulary abilities were associated with better recognition in noise for sentences and word sequences, but not for words. Working memory and language both influence children's speech recognition in noise, but the relationships vary across types of stimuli. These findings suggest that clinical assessment of speech recognition is likely to reflect underlying cognitive and linguistic abilities, in addition to a child's auditory skills, consistent with the Ease of Language Understanding model.

  20. Individual differences in language and working memory affect children’s speech recognition in noise

    Science.gov (United States)

    McCreery, Ryan W.; Spratford, Meredith; Kirby, Benjamin; Brennan, Marc

    2017-01-01

    Objective We examined how cognitive and linguistic skills affect speech recognition in noise for children with normal hearing. Children with better working memory and language abilities were expected to have better speech recognition in noise than peers with poorer skills in these domains. Design As part of a prospective, cross-sectional study, children with normal hearing completed speech recognition in noise for three types of stimuli: (1) monosyllabic words, (2) syntactically correct but semantically anomalous sentences and (3) semantically and syntactically anomalous word sequences. Measures of vocabulary, syntax and working memory were used to predict individual differences in speech recognition in noise. Study sample Ninety-six children with normal hearing, who were between 5 and 12 years of age. Results Higher working memory was associated with better speech recognition in noise for all three stimulus types. Higher vocabulary abilities were associated with better recognition in noise for sentences and word sequences, but not for words. Conclusions Working memory and language both influence children’s speech recognition in noise, but the relationships vary across types of stimuli. These findings suggest that clinical assessment of speech recognition is likely to reflect underlying cognitive and linguistic abilities, in addition to a child’s auditory skills, consistent with the Ease of Language Understanding model. PMID:27981855

  1. Individuation among bedouin versus urban arab adolescents: ethnic and gender differences.

    Science.gov (United States)

    Dwairy, Marwan

    2004-11-01

    Three scales assessing individuation (Objective Measure of Ego-Identity Status [OMEIS], Separation-Individuation Test of Adolescence [SITA], and Multigenerational Interconnectedness Scale [MIS]) were administered to 40 female and 38 male Bedouin Arab adolescents and to 39 female and 38 male urban Arab adolescents in Grade 12. It was hypothesized that Bedouin Arab adolescents and female adolescents would manifest less individuation than urban Arab adolescents and male adolescents, respectively. Results from the OMEIS revealed that the identity foreclosed mean of the Bedouin adolescents was higher than that of the urban adolescents. As for the SITA, significant differences were found between Bedouin and urban Arabs in terms of dependency denial, separation anxiety, teacher enmeshment, peer enmeshment, and rejection expectancy. Significant gender differences were found in regard to dependency denial, and a borderline difference was found for separation anxiety. Significant effects of ethnicity and gender were found on the financial interconnectedness subscale of the MIS. The results support the present hypotheses concerning ethnicity differences and indicate that urbanization seems to narrow the differences in individuation between male and female adolescents. 2004 APA

  2. Is it Worth Comparing Different Bankruptcy Models?

    Directory of Open Access Journals (Sweden)

    Miroslava Dolejšová

    2015-01-01

    Full Text Available The aim of this paper is to compare the performance of small enterprises in the Zlín and Olomouc Regions. These enterprises were assessed using the Altman Z-Score model, the IN05 model, the Zmijewski model and the Springate model. The batch selected for this analysis included 16 enterprises from the Zlín Region and 16 enterprises from the Olomouc Region. Financial statements subjected to the analysis are from 2006 and 2010. The statistical data analysis was performed using the one-sample z-test for proportions and the paired t-test. The outcomes of the evaluation run using the Altman Z-Score model, the IN05 model and the Springate model revealed the enterprises to be financially sound, but the Zmijewski model identified them as being insolvent. The one-sample z-test for proportions confirmed that at least 80% of these enterprises show a sound financial condition. A comparison of all models has emphasized the substantial difference produced by the Zmijewski model. The paired t-test showed that the financial performance of small enterprises had remained the same during the years involved. It is recommended that small enterprises assess their financial performance using two different bankruptcy models. They may wish to combine the Zmijewski model with any bankruptcy model (the Altman Z-Score model, the IN05 model or the Springate model to ensure a proper method of analysis.

  3. Behavioural plasticity across social contexts is regulated by the directionality of inter-individual differences.

    Science.gov (United States)

    Guayasamin, Olivia L; Couzin, Iain D; Miller, Noam Y

    2017-08-01

    An individual's behavioural phenotype is a combination of its unique behavioural propensities and its responsiveness to environmental variation, also known as behavioural plasticity. In social species, we must not only explore how individuals respond to variations in the physical environment but also how they react to changes in their social environment. A growing body of work has demonstrated that the behavioural heterogeneity of a group can alter its responsiveness, decision making, and fitness. Whether an individual is more or less extreme than a partner - what we term its 'relative personality' - may also alter individual behavioural responses. We determined exploratory tendencies of individual zebrafish (Danio rerio) and then constructed pairs with varying differences in 'relative personality' to determine the effect of differences between partners on behavioural plasticity. We find that relative personality, but not the magnitude of the difference between partners, is the most important determinant of behavioural plasticity across social treatments. Despite this overall effect, pairs of fish exhibited no predictable leader-follower interactions, suggesting that details of the experimental paradigm may be important in shaping social dynamics. Copyright © 2016 Elsevier B.V. All rights reserved.

  4. Early development and the emergence of individual differences in behavior among littermates of wild rabbit pups.

    Science.gov (United States)

    Rödel, Heiko G; Bautista, Amando; Roder, Manuel; Gilbert, Caroline; Hudson, Robyn

    2017-05-01

    The ontogeny of associated individual differences in behavior and physiology during early postnatal life, and in particular the emergence of such differences among litter siblings, has been hardly explored in mammals under natural conditions. We studied such within-litter differences in behavior in European rabbit pups Oryctolagus cuniculus prior to weaning, and whether and how these differences co-varied with other individual characteristics such as postnatal body temperature and early growth. The study was conducted under semi-natural conditions in a colony of rabbits of wild origin, where the young were born and developed in nursery burrows. We equipped two siblings per litter with interscapular skin temperature loggers on postnatal day 2 and recorded temperature profiles for 48h. Individual body (skin) temperatures of pups within litters were repeatable across time, indicating the existence of consistent individual differences. Such differences within litters were associated with relative differences in pre-weaning growth, revealing that relatively warmer pups showed a greater increase in body mass during the nest period. Between postnatal days 12 and 17, after the pups had reached a developmental stage of greater mobility, we carried out different behavioral tests: a handling-restraint test, an open field test and a jump-down test from a platform. Individual responses in the former two tests were associated, as those pups showing a quicker struggling response to restraint during handling also exhibited greater exploratory activity in the open field. This correlation across contexts suggests the existence of personality types in wild rabbits at an early developmental stage. Furthermore, pups' behavioral responses were strongly associated with their relative within-litter body mass at testing. Animals with a lower body mass compared to their siblings showed a relatively quicker struggle response to handling restraint and covered a relatively larger distance in

  5. Limited evidence of individual differences in holistic processing in different versions of the part-whole paradigm.

    Science.gov (United States)

    Sunday, Mackenzie A; Richler, Jennifer J; Gauthier, Isabel

    2017-07-01

    The part-whole paradigm was one of the first measures of holistic processing and it has been used to address several topics in face recognition, including its development, other-race effects, and more recently, whether holistic processing is correlated with face recognition ability. However the task was not designed to measure individual differences and it has produced measurements with low reliability. We created a new holistic processing test designed to measure individual differences based on the part-whole paradigm, the Vanderbilt Part Whole Test (VPWT). Measurements in the part and whole conditions were reliable, but, surprisingly, there was no evidence for reliable individual differences in the part-whole index (how well a person can take advantage of a face part presented within a whole face context compared to the part presented without a whole face) because part and whole conditions were strongly correlated. The same result was obtained in a version of the original part-whole task that was modified to increase its reliability. Controlling for object recognition ability, we found that variance in the whole condition does not predict any additional variance in face recognition over what is already predicted by performance in the part condition.

  6. Relationships between individual differences in motivation and borderline personality disorder, psychopathy, and maladjustment.

    Science.gov (United States)

    Bernard, Larry C

    2013-08-01

    Two studies investigate relationships between individual differences in motivation and borderline personality disorder, psychopathy, and maladjustment. Participants completed the Brief Assessment of Individual Motives 1--Revised, a measure of 15 putative evolved motives (i.e., "traits of action"). In Study 1, N = 147 adult participants also completed the Borderline Personality Questionnaire and Self-Report Psychopathy III Questionnaire (SRP III). In Study 2, N = 135 college age participants also completed the SRP III and the Counseling Center Assessment of Psychological Symptoms-62. Regression analyses suggested that individual differences in motivational traits account for moderate amounts of variance in measures of antisocial personality disorder, psychopathy, and maladjustment. They also suggested that lower motivation to engage in cooperative behaviors (e.g., sharing resources and forming coalitions) is related to impaired interpersonal relationships and maladjustment.

  7. Happiness as a belief system: individual differences and priming in emotion judgments.

    Science.gov (United States)

    Robinson, Michael D; Kirkeby, Ben S

    2005-08-01

    Three studies involving 104 undergraduates sought to examine how an individual's level of life satisfaction organizes their knowledge concerning the self's emotions. Participants judged the self's positive and negative emotions within a computerized task. Key results sought to determine whether judging two positive emotions in a consecutive sequence speeds the second judgment--a pattern of priming that would suggest a tighter, more interconnected structure in semantic memory related to one's positive emotions. As expected, individual differences in life satisfaction predicted the magnitude of this priming effect (Studies 1 & 2), which appeared to be unique to judgments of the self's emotions (Study 3). The results indicate that happy, relative to less happy, individuals organize information concerning their positive emotions in a qualitatively different and tighter semantic manner.

  8. Individual differences in circadian locomotor parameters correlate with anxiety- and depression-like behavior.

    Directory of Open Access Journals (Sweden)

    Jeffrey Anyan

    Full Text Available Disrupted circadian rhythms are a core feature of mood and anxiety disorders. Circadian rhythms are coordinated by a light-entrainable master clock located in the suprachiasmatic nucleus. Animal models of mood and anxiety disorders often exhibit blunted rhythms in locomotor activity and clock gene expression. Interestingly, the changes in circadian rhythms correlate with mood-related behaviours. Although animal models of depression and anxiety exhibit aberrant circadian rhythms in physiology and behavior, it is possible that the methodology being used to induce the behavioral phenotype (e.g., brain lesions, chronic stress, global gene deletion affect behavior independently of circadian system. This study investigates the relationship between individual differences in circadian locomotor parameters and mood-related behaviors in healthy rats. The circadian phenotype of male Lewis rats was characterized by analyzing wheel running behavior under standard 12h:12h LD conditions, constant dark, constant light, and rate of re-entrainment to a phase advance. Rats were then tested on a battery of behavioral tests: activity box, restricted feeding, elevated plus maze, forced swim test, and fear conditioning. Under 12h:12h LD conditions, percent of daily activity in the light phase and variability in activity onset were associated with longer latency to immobility in the forced swim test. Variability in onset also correlated positively with anxiety-like behavior in the elevated plus maze. Rate of re-entrainment correlated positively with measures of anxiety in the activity box and elevated plus maze. Lastly, we found that free running period under constant dark was associated with anxiety-like behaviors in the activity box and elevated plus maze. Our results provide a previously uncharacterized relationship between circadian locomotor parameters and mood-related behaviors in healthy rats and provide a basis for future examination into circadian clock

  9. Individual Differences in Personality Masculinity-Femininity: Examining the Effects of Genes, Environment, and Prenatal Hormone Transfer.

    Science.gov (United States)

    Verweij, Karin J H; Mosing, Miriam A; Ullén, Fredrik; Madison, Guy

    2016-04-01

    Males and females score differently on some personality traits, but the underlying etiology of these differences is not well understood. This study examined genetic, environmental, and prenatal hormonal influences on individual differences in personality masculinity-femininity (M-F). We used Big-Five personality inventory data of 9,520 Swedish twins (aged 27 to 54) to create a bipolar M-F personality scale. Using biometrical twin modeling, we estimated the influence of genetic and environmental factors on individual differences in a M-F personality score. Furthermore, we tested whether prenatal hormone transfer may influence individuals' M-F scores by comparing the scores of twins with a same-sex versus those with an opposite-sex co-twin. On average, males scored 1.09 standard deviations higher than females on the created M-F scale. Around a third of the variation in M-F personality score was attributable to genetic factors, while family environmental factors had no influence. Males and females from opposite-sex pairs scored significantly more masculine (both approximately 0.1 SD) than those from same-sex pairs. In conclusion, genetic influences explain part of the individual differences in personality M-F, and hormone transfer from the male to the female twin during pregnancy may increase the level of masculinization in females. Additional well-powered studies are needed to clarify this association and determine the underlying mechanisms in both sexes.

  10. Correcting for different use of the scale and the need for further analysis of individual differences in sensory analysis

    DEFF Research Database (Denmark)

    Romano, R.; Brockhoff, Per B.; Hersleth, M.

    2008-01-01

    in descriptive sensory analysis there exist individual differences between assessors giving intensity scores on a continuous scale for a number of sensory attributes. The present paper is a study of the importance of scaling effects. In particular, different ways of reducing such effects....... The data set used in the paper is based on sensory evaluations of 14 cheese samples profiled by a panel of 12 assessors using 12 descriptors in two replicates. The paper has demonstrated that the simple standardization scalings are only proper scaling estimates under quite restrictive assumptions whilst...

  11. Feature-Based Change Detection Reveals Inconsistent Individual Differences in Visual Working Memory Capacity.

    Science.gov (United States)

    Ambrose, Joseph P; Wijeakumar, Sobanawartiny; Buss, Aaron T; Spencer, John P

    2016-01-01

    Visual working memory (VWM) is a key cognitive system that enables people to hold visual information in mind after a stimulus has been removed and compare past and present to detect changes that have occurred. VWM is severely capacity limited to around 3-4 items, although there are robust individual differences in this limit. Importantly, these individual differences are evident in neural measures of VWM capacity. Here, we capitalized on recent work showing that capacity is lower for more complex stimulus dimension. In particular, we asked whether individual differences in capacity remain consistent if capacity is shifted by a more demanding task, and, further, whether the correspondence between behavioral and neural measures holds across a shift in VWM capacity. Participants completed a change detection (CD) task with simple colors and complex shapes in an fMRI experiment. As expected, capacity was significantly lower for the shape dimension. Moreover, there were robust individual differences in behavioral estimates of VWM capacity across dimensions. Similarly, participants with a stronger BOLD response for color also showed a strong neural response for shape within the lateral occipital cortex, intraparietal sulcus (IPS), and superior IPS. Although there were robust individual differences in the behavioral and neural measures, we found little evidence of systematic brain-behavior correlations across feature dimensions. This suggests that behavioral and neural measures of capacity provide different views onto the processes that underlie VWM and CD. Recent theoretical approaches that attempt to bridge between behavioral and neural measures are well positioned to address these findings in future work.

  12. Individualized Risk Model for Venous Thromboembolism After Total Joint Arthroplasty.

    Science.gov (United States)

    Parvizi, Javad; Huang, Ronald; Rezapoor, Maryam; Bagheri, Behrad; Maltenfort, Mitchell G

    2016-09-01

    Venous thromboembolism (VTE) after total joint arthroplasty (TJA) is a potentially fatal complication. Currently, a standard protocol for postoperative VTE prophylaxis is used that makes little distinction between patients at varying risks of VTE. We sought to develop a simple scoring system identifying patients at higher risk for VTE in whom more potent anticoagulation may need to be administered. Utilizing the National Inpatient Sample data, 1,721,806 patients undergoing TJA were identified, among whom 15,775 (0.9%) developed VTE after index arthroplasty. Among the cohort, all known potential risk factors for VTE were assessed. An initial logistic regression model using potential predictors for VTE was performed. Predictors with little contribution or poor predictive power were pruned from the data, and the model was refit. After pruning of variables that had little to no contribution to VTE risk, using the logistic regression, all independent predictors of VTE after TJA were identified in the data. Relative weights for each factor were determined. Hypercoagulability, metastatic cancer, stroke, sepsis, and chronic obstructive pulmonary disease had some of the highest points. Patients with any of these conditions had risk for postoperative VTE that exceeded the 3% rate. Based on the model, an iOS (iPhone operating system) application was developed (VTEstimator) that could be used to assign patients into low or high risk for VTE after TJA. We believe individualization of VTE prophylaxis after TJA can improve the efficacy of preventing VTE while minimizing untoward risks associated with the administration of anticoagulation. Copyright © 2016 Elsevier Inc. All rights reserved.

  13. An individual-based probabilistic model for simulating fisheries population dynamics

    Directory of Open Access Journals (Sweden)

    Jie Cao

    2016-12-01

    Full Text Available The purpose of stock assessment is to support managers to provide intelligent decisions regarding removal from fish populations. Errors in assessment models may have devastating impacts on the population fitness and negative impacts on the economy of the resource users. Thus, accuracte estimations of population size, growth rates are critical for success. Evaluating and testing the behavior and performance of stock assessment models and assessing the consequences of model mis-specification and the impact of management strategies requires an operating model that accurately describe the dynamics of the target species, and can resolve spatial and seasonal changes. In addition, the most thorough evaluations of assessment models use an operating model that takes a different form than the assessment model. This paper presents an individual-based probabilistic model used to simulate the complex dynamics of populations and their associated fisheries. Various components of population dynamics are expressed as random Bernoulli trials in the model and detailed life and fishery histories of each individual are tracked over their life span. The simulation model is designed to be flexible so it can be used for different species and fisheries. It can simulate mixing among multiple stocks and link stock-recruit relationships to environmental factors. Furthermore, the model allows for flexibility in sub-models (e.g., growth and recruitment and model assumptions (e.g., age- or size-dependent selectivity. This model enables the user to conduct various simulation studies, including testing the performance of assessment models under different assumptions, assessing the impacts of model mis-specification and evaluating management strategies.

  14. Using individual differences to predict job performance: correcting for direct and indirect restriction of range.

    Science.gov (United States)

    Sjöberg, Sofia; Sjöberg, Anders; Näswall, Katharina; Sverke, Magnus

    2012-08-01

    The present study investigates the relationship between individual differences, indicated by personality (FFM) and general mental ability (GMA), and job performance applying two different methods of correction for range restriction. The results, derived by analyzing meta-analytic correlations, show that the more accurate method of correcting for indirect range restriction increased the operational validity of individual differences in predicting job performance and that this increase primarily was due to general mental ability being a stronger predictor than any of the personality traits. The estimates for single traits can be applied in practice to maximize prediction of job performance. Further, differences in the relative importance of general mental ability in relation to overall personality assessment methods was substantive and the estimates provided enables practitioners to perform a correct utility analysis of their overall selection procedure. © 2012 The Authors. Scandinavian Journal of Psychology © 2012 The Scandinavian Psychological Associations.

  15. Individual Differences in Visual Self-Recognition as a Function of Mother-Infant Attachment Relationship.

    Science.gov (United States)

    Lewis, Michael; And Others

    1985-01-01

    Compares attachment relationships of infants at 12 months to their visual self-recognition at both 18 and 24 months. Individual differences in early attachment relations were related to later self-recognition. In particular, insecurely attached infants showed a trend toward earlier self-recognition than did securely attached infants. (Author/NH)

  16. A Descriptive Study of Individual and Cross-Cultural Differences in Statistics Anxiety

    Science.gov (United States)

    Baloglu, Mustafa; Deniz, M. Engin; Kesici, Sahin

    2011-01-01

    The present study investigated individual and cross-cultural differences in statistics anxiety among 223 Turkish and 237 American college students. A 2 x 2 between-subjects factorial multivariate analysis of covariance (MANCOVA) was performed on the six dependent variables which are the six subscales of the Statistical Anxiety Rating Scale.…

  17. Pre-trauma individual differences in extinction learning predict posttraumatic stress

    NARCIS (Netherlands)

    Lommen, M.J.J.; Engelhard, I.M.; Sijbrandij, M.; van Hout, M.A.; Hermans, D.

    2013-01-01

    In the aftermath of a traumatic event, many people suffer from psychological distress, but only a minority develops posttraumatic stress disorder (PTSD). Pre-trauma individual differences in fear conditioning, most notably reduced extinction learning, have been proposed as playing an important role

  18. Determinants of success in native and non-native listening comprehension: an individual differences approach

    NARCIS (Netherlands)

    Andringa, S.; Olsthoorn, N.; van Beuningen, C.; Schoonen, R.; Hulstijn, J.

    2012-01-01

    The goal of this study was to explain individual differences in both native and non-native listening comprehension; 121 native and 113 non-native speakers of Dutch were tested on various linguistic and nonlinguistic cognitive skills thought to underlie listening comprehension. Structural equation

  19. Vocational Rehabilitation Service Patterns and Outcomes for Individuals with Autism of Different Ages

    Science.gov (United States)

    Chen, June L.; Sung, Connie; Pi, Sukyeong

    2015-01-01

    Young adults with autism spectrum disorders (ASD) often experience employment difficulties. Using Rehabilitation Service Administration data (RSA-911), this study investigated the service patterns and factors related to the employment outcomes of individuals with ASD in different age groups. Hierarchical logistic regression analyses were conducted…

  20. Individual differences on social comparison : properties of the orientation Spanish scale towards social comparison

    NARCIS (Netherlands)

    Buunk, AP; Belmonte, J; Peiro, JM; Zurriaga, R; Gibbons, FX

    2005-01-01

    This paper describes the development and the properties of the INCOM-E, the Spanish language version of the INCOM, a measure to assess individual differences in social comparison orientation that was originally developed simultaneously in English and in Dutch. In both Study 1 (including 212

  1. Individual differences in social comparison : Development of a scale of social comparison orientation

    NARCIS (Netherlands)

    Gibbons, FX; Buunk, BP

    Development and validation of a measure of individual differences in social comparison orientation (the Iowa-Netherlands Comparison Orientation Measure [INCOM]) are described. Assuming that the tendency toward social comparison is universal, the scale was constructed so as to be appropriate to and

  2. Individual Differences in Emotional Reactivity and Academic Achievement: A Psychophysiological Study

    Science.gov (United States)

    Scrimin, Sara; Altoè, Gianmarco; Moscardino, Ughetta; Pastore, Massimiliano; Mason, Lucia

    2016-01-01

    Factors related to grade point average (GPA) are of great importance for students' success. Yet, little is known about the impact of individual differences in emotional reactivity on students' academic performance. We aimed to examine the emotional reactivity-GPA link and to assess whether self-esteem and psychological distress moderate this…

  3. Variation in Cognitive Failures: An Individual Differences Investigation of Everyday Attention and Memory Failures

    Science.gov (United States)

    Unsworth, Nash; Brewer, Gene A.; Spillers, Gregory J.

    2012-01-01

    The present study examined individual differences in everyday cognitive failures assessed by diaries. A large sample of participants completed various cognitive ability measures in the laboratory. Furthermore, a subset of these participants also recorded everyday cognitive failures (attention, retrospective memory, and prospective memory failures)…

  4. Individual differences in executive functions, training effects & quality of life of children with autism spectrum disorders

    NARCIS (Netherlands)

    de Vries, M.

    2015-01-01

    Children with autism spectrum disorders (ASD) appear to experience executive functioning (EF) problems, but there are large individual differences in EF-profiles in ASD. In the current study the majority of children with ASD (8-12 years) actually experienced no cognitive flexibility deficits.

  5. Analyzing Individual Differences in Vocational, Leisure, and Family Interests: A Multitrait-Multimethod Approach

    Science.gov (United States)

    Gaudron, Jean-Philippe; Vautier, Stephane

    2007-01-01

    This study investigates the latent structure of individual differences in vocational, leisure, and family interests. The participants consisted of 302 French adults who rated their like or dislike for activities based on Holland's RIASEC typology and presented in three life domains: work, family and leisure. The multitrait-multimethod model…

  6. Individual differences in discriminatory fear learning under conditions of ambiguity: a vulnerability factor for anxiety disorders?

    NARCIS (Netherlands)

    Arnaudova, I.; Krypotos, A.M.; Effting, M.; Boddez, Y.; Kindt, M.; Beckers, T.

    2013-01-01

    Complex fear learning procedures might be better suited than the common differential fear-conditioning paradigm for detecting individual differences related to vulnerability for anxiety disorders. Two such procedures are the blocking procedure and the protection-from-overshadowing procedure. Their

  7. Similarities and differences in dream content at the cross-cultural, gender, and individual levels.

    Science.gov (United States)

    William Domhoff, G; Schneider, Adam

    2008-12-01

    The similarities and differences in dream content at the cross-cultural, gender, and individual levels provide one starting point for carrying out studies that attempt to discover correspondences between dream content and various types of waking cognition. Hobson and Kahn's (Hobson, J. A., & Kahn, D. (2007). Dream content: Individual and generic aspects. Consciousness and Cognition, 16, 850-858.) conclusion that dream content may be more generic than most researchers realize, and that individual differences are less salient than usually thought, provides the occasion for a review of findings based on the Hall and Van de Castle (Hall, C., & Van de Castle, R. (1966). The content analysis of dreams. New York: Appleton-Century-Crofts.) coding system for the study of dream content. Then new findings based on a computationally intensive randomization strategy are presented to show the minimum sample sizes needed to detect gender and individual differences in dream content. Generally speaking, sample sizes of 100-125 dream reports are needed because most dream elements appear in less than 50% of dream reports and the magnitude of the differences usually is not large.

  8. Individual Differences in the Expression of Conditioned Fear Are Associated with Endogenous Fibroblast Growth Factor 2

    Science.gov (United States)

    Graham, Bronwyn M.; Richardson, Rick

    2016-01-01

    These experiments examined the relationship between the neurotrophic factor fibroblast growth factor 2 (FGF2) and individual differences in the expression of conditioned fear. Experiments 1 and 2 demonstrated that rats naturally expressing low levels of contextual or cued fear have higher levels of hippocampal FGF2 relative to rats that express…

  9. Working Memory Capacity and Mobile Multimedia Learning Environments: Individual Differences in Learning While Mobile

    Science.gov (United States)

    Doolittle, Peter E.; Mariano, Gina J.

    2008-01-01

    The present study examined the effects of individual differences in working memory capacity (WMC) on learning from an historical inquiry multimedia tutorial in stationary versus mobile learning environments using a portable digital media player (i.e., iPod). Students with low (n = 44) and high (n = 40) working memory capacity, as measured by the…

  10. Perceived helplessness is associated with individual differences in the central motor output system.

    Science.gov (United States)

    Salomons, Tim V; Moayedi, Massieh; Weissman-Fogel, Irit; Goldberg, Michael B; Freeman, Bruce V; Tenenbaum, Howard C; Davis, Karen D

    2012-05-01

    Learned helplessness is a maladaptive response to uncontrollable stress characterized by impaired motor escape responses, reduced motivation and learning deficits. There are important individual differences in the likelihood of becoming helpless following exposure to uncontrollable stress but little is known about the neural mechanisms underlying these individual differences. Here we used structural MRI to measure gray and white matter in individuals with chronic pain, a population at high risk for helplessness due to prolonged exposure to a poorly controlled stressor (pain). Given that self-reported helplessness is predictive of treatment outcomes in chronic pain, understanding such differences might provide valuable clinical insight. We found that the magnitude of self-reported helplessness correlated with cortical thickness in the supplementary motor area (SMA) and midcingulate cortex, regions implicated in cognitive aspects of motor behavior. We then examined the white matter connectivity of these regions and found that fractional anisotropy of connected white matter tracts along the corticospinal tract was associated with helplessness and mediated the relationship between SMA cortical thickness and helplessness. These data provide novel evidence that links individual differences in the motor output pathway with perceived helplessness over a chronic and poorly controlled stressor. © 2012 The Authors. European Journal of Neuroscience © 2012 Federation of European Neuroscience Societies and Blackwell Publishing Ltd.

  11. Peer Victimization and Aggression: Moderation by Individual Differences in Salivary Cortisol and Alpha-Amylase

    Science.gov (United States)

    Rudolph, Karen D.; Troop-Gordon, Wendy; Granger, Douglas A.

    2010-01-01

    This research examined whether variations in salivary measures of the hypothalamic-pituitary-adrenal axis (cortisol) and autonomic nervous system (alpha amylase [sAA]) contribute to individual differences in the association between peer victimization and aggression. Children (N = 132; M age = 9.46 years, SD = 0.33) completed a measure of peer…

  12. Individual Differences in the Relationship between Satisfaction with Job Rewards and Job Satisfaction

    Science.gov (United States)

    Hofmans, Joeri; De Gieter, Sara; Pepermans, Roland

    2013-01-01

    Although previous research often showed a positive relationship between pay satisfaction and job satisfaction, we dispute the universality of this finding. Cluster-wise regression analyses on three samples consistently show that two types of individuals can be distinguished, each with a different job reward-job satisfaction relationship. For the…

  13. The Roles of Experience, Gender, and Individual Differences in Statistical Reasoning

    Science.gov (United States)

    Martin, Nadia; Hughes, Jeffrey; Fugelsang, Jonathan

    2017-01-01

    We examine the joint effects of gender and experience on statistical reasoning. Participants with various levels of experience in statistics completed the Statistical Reasoning Assessment (Garfield, 2003), along with individual difference measures assessing cognitive ability and thinking dispositions. Although the performance of both genders…

  14. Individualism, Collectivism, and Client Expression of Different Emotions: Their Relations to Perceived Counselor Effectiveness

    Science.gov (United States)

    Seo, Young Seok

    2011-01-01

    This study examined how individualism, collectivism, and counselor emphasis of different client emotions were related to perceived counselor effectiveness. Data were collected from 192 (122 women and 70 men) Korean students attending a large university in South Korea and from 170 (115 women and 55 men) American students attending a large…

  15. Fight or freeze? Individual differences in investors’ motivational systems and trading in experimental asset markets

    NARCIS (Netherlands)

    Muehlfeld, K.S.; Weitzel, G.U.; van Witteloostuijn, A.

    2012-01-01

    We analyze investors’ trading behavior, particularly their coping with fundamental shocks in asset value, depending on individual differences in the sensitivity of two basic neurophysiological systems—the Behavioral Approach System (BAS), the ‘driving force’ of human behavior, and the Behavioral

  16. Fight or freeze? Individual differences in investors' motivational systems and trading in experimental asset markets

    NARCIS (Netherlands)

    Mühlfeld, K.; Weitzel, U.; van Witteloostuijn, A.

    2013-01-01

    We analyze investors’ trading behavior, particularly their coping with fundamental shocks in asset value, depending on individual differences in the sensitivity of two basic neurophysiological systems—the Behavioral Approach System (BAS), the ‘driving force’ of human behavior, and the Behavioral

  17. Individual Differences in Digit Span, Susceptibility to Proactive Interference, and Aptitude/Achievement Test Scores.

    Science.gov (United States)

    Dempster, Frank N.; Cooney, John B.

    1982-01-01

    Individual differences in digit span, susceptibility to proactive interference, and various aptitude/achievement test scores were investigated in two experiments with college students. Results indicated that digit span was strongly correlated with aptitude/achievement scores, but did not indicate that susceptibility to proactive interference…

  18. The Relation between Navigation Strategy and Associative Memory: An Individual Differences Approach

    Science.gov (United States)

    Ngo, Chi T.; Weisberg, Steven M.; Newcombe, Nora S.; Olson, Ingrid R.

    2016-01-01

    Although the hippocampus is implicated in both spatial navigation and associative memory, very little is known about whether individual differences in the 2 domains covary. People who prefer to navigate using a hippocampal-dependent place strategy may show better performance on associative memory tasks than those who prefer a caudate-dependent…

  19. Individual Differences in EEG Spectral Power Reflect Genetic Variance in Gray and White Matter Volumes

    NARCIS (Netherlands)

    Smit, D.J.A.; Boomsma, D.I.; Schnack, H.G.; Hulshoff Pol, H.E.; de Geus, E.J.C.

    2012-01-01

    The human electroencephalogram (EEG) consists of oscillations that reflect the summation of postsynaptic potentials at the dendritic tree of cortical neurons. The strength of the oscillations (EEG power) is a highly genetic trait that has been related to individual differences in many phenotypes,

  20. Individual differences in decision making competence revealed by multivariate fMRI.

    Science.gov (United States)

    Talukdar, Tanveer; Román, Francisco J; Operskalski, Joachim T; Zwilling, Christopher E; Barbey, Aron K

    2018-06-01

    While an extensive literature in decision neuroscience has elucidated the neurobiological foundations of decision making, prior research has focused primarily on group-level effects in a sample population. Due to the presence of inherent differences between individuals' cognitive abilities, it is also important to examine the neural correlates of decision making that explain interindividual variability in cognitive performance. This study therefore investigated how individual differences in decision making competence, as measured by the Adult Decision Making Competence (A-DMC) battery, are related to functional brain connectivity patterns derived from resting-state fMRI data in a sample of 304 healthy participants. We examined connectome-wide associations, identifying regions within frontal, parietal, temporal, and occipital cortex that demonstrated significant associations with decision making competence. We then assessed whether the functional interactions between brain regions sensitive to decision making competence and seven intrinsic connectivity networks (ICNs) were predictive of specific facets of decision making assessed by subtests of the A-DMC battery. Our findings suggest that individual differences in specific facets of decision making competence are mediated by ICNs that support executive, social, and perceptual processes, and motivate an integrative framework for understanding the neural basis of individual differences in decision making competence. © 2018 Wiley Periodicals, Inc.