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Sample records for modeling individual differences

  1. Individual Differences in Equity Models

    Science.gov (United States)

    Hofmans, Joeri

    2012-01-01

    In the present paper, we (1) study whether people differ in the equity models they use, and (2) test whether individual differences in equity models relate to individual differences in equity sensitivity. To achieve this goal, an Information Integration experiment was performed in which participants were given information on the performance of two…

  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. 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

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

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    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.

  5. Holland's RIASEC Model as an Integrative Framework for Individual Differences

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    Armstrong, Patrick Ian; Day, Susan X.; McVay, Jason P.; Rounds, James

    2008-01-01

    Using data from published sources, the authors investigated J. L. Holland's (1959, 1997) theory of interest types as an integrative framework for organizing individual differences variables that are used in counseling psychology. Holland's interest types were used to specify 2- and 3-dimensional interest structures. In Study 1, measures of…

  6. Holland's RIASEC Model as an Integrative Framework for Individual Differences

    Science.gov (United States)

    Armstrong, Patrick Ian; Day, Susan X.; McVay, Jason P.; Rounds, James

    2008-01-01

    Using data from published sources, the authors investigated J. L. Holland's (1959, 1997) theory of interest types as an integrative framework for organizing individual differences variables that are used in counseling psychology. Holland's interest types were used to specify 2- and 3-dimensional interest structures. In Study 1, measures of…

  7. Ignoring Individual Differences in Times of Assessment in Growth Curve Modeling

    Science.gov (United States)

    Coulombe, Patrick; Selig, James P.; Delaney, Harold D.

    2016-01-01

    Researchers often collect longitudinal data to model change over time in a phenomenon of interest. Inevitably, there will be some variation across individuals in specific time intervals between assessments. In this simulation study of growth curve modeling, we investigate how ignoring individual differences in time points when modeling change over…

  8. Three-Mode Models and Individual Differences in Semantic Differential Data.

    Science.gov (United States)

    Murakami, Takashi; Kroonenberg, Pieter M.

    2003-01-01

    Demonstrated how individual differences in semantic differential data can be modeled and assessed using three-mode models by studying the characterization of Chopin's "Preludes" by 38 Japanese college students. (SLD)

  9. Sex Differences and Individual Differences

    Science.gov (United States)

    Plomin, Robert; Foch, Terryl T.

    1981-01-01

    Sex differences and their relationship to individual differences were examined for Maccoby and Jacklin's sex differences summaries, for a diverse set of measures of specific cognitive abilities (including verbal ability), and for objective personality assessments of 216 school-age children. Average differences between groups appeared to be trivial…

  10. Using Decision Models to Enhance Investigations of Individual Differences in Cognitive Neuroscience

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    White, Corey N.; Curl, Ryan A.; Sloane, Jennifer F.

    2016-01-01

    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. PMID:26903896

  11. 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.

  12. 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.

  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. Animal models of human psychopathology based on individual differences in novelty-seeking and anxiety.

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    Pawlak, Cornelius R; Ho, Ying-Jui; Schwarting, Rainer K W

    2008-10-01

    The role of individual factors in behavioural neuroscience is an important, but still neglected area of research. The present review aims to give, first, an outline of the most elaborated theory on animal behaviour, and second, an overview of systematic approaches of historic and present animal models of human psychopathology based on individual differences. This overview will be focused on animal models of unselected subjects (i.e. natural variance of a specific behaviour within a given population) and selected breeding for a specific behaviour. Accordingly, an outline of the personality model from Gray and McNaughton of individual behaviour in animals is given first. Then, a comprehensive overview of past and current animal models in novelty-seeking (i.e. psychomotor activation and exploration behaviour) based on systematic individual differences and its relationship to addiction is presented. Third, this will be followed by a comprehensive overview of individual differences in previous and present animal models for anxiety. Finally, critical aspects of such approaches in animal research are discussed, and suggestions are given where to go from here.

  15. 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.

  16. Individual Differences in Affect.

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    Haviland, Jeannette

    This paper argues that infants' affect patterns are innate and are meaningful indicators of individual differences in internal state. Videotapes of seven infants' faces were coded using an ethogram; the movement of the eyebrow, eye direction, eye openness, mouth shape, mouth position, lip position, and tongue protrusion were assessed…

  17. A model-driven approach to quantify migration patterns: individual, regional and yearly differences.

    Science.gov (United States)

    Bunnefeld, Nils; Börger, Luca; van Moorter, Bram; Rolandsen, Christer M; Dettki, Holger; Solberg, Erling Johan; Ericsson, Göran

    2011-03-01

    1. Animal migration has long intrigued scientists and wildlife managers alike, yet migratory species face increasing challenges because of habitat fragmentation, climate change and over-exploitation. Central to the understanding migratory species is the objective discrimination between migratory and nonmigratory individuals in a given population, quantifying the timing, duration and distance of migration and the ability to predict migratory movements. 2. Here, we propose a uniform statistical framework to (i) separate migration from other movement behaviours, (ii) quantify migration parameters without the need for arbitrary cut-off criteria and (iii) test predictability across individuals, time and space. 3. We first validated our novel approach by simulating data based on established theoretical movement patterns. We then formulated the expected shapes of squared displacement patterns as nonlinear models for a suite of movement behaviours to test the ability of our method to distinguish between migratory movement and other movement types. 4. We then tested our approached empirically using 108 wild Global Positioning System (GPS)-collared moose Alces alces in Scandinavia as a study system because they exhibit a wide range of movement behaviours, including resident, migrating and dispersing individuals, within the same population. Applying our approach showed that 87% and 67% of our Swedish and Norwegian subpopulations, respectively, can be classified as migratory. 5. Using nonlinear mixed effects models for all migratory individuals we showed that the distance, timing and duration of migration differed between the sexes and between years, with additional individual differences accounting for a large part of the variation in the distance of migration but not in the timing or duration. Overall, the model explained most of the variation (92%) and also had high predictive power for the same individuals over time (69%) as well as between study populations (74

  18. A mediation model of individual differences in attitudes toward affirmative actions for women.

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    Moscoso, Silvia; García-Izquierdo, Antonio L; Bastida, María

    2012-06-01

    A mediation model of the relation between gender and attitudes toward affirmative action in favor of working women was tested. Four mediation variables were considered: perceived unfairness in the situation of working women, perceived threat to the non-designated group (men), self-esteem, and gender self-concept (masculinity and femininity). 192 women and 128 men, with differing occupations, participated. Gender affects individuals' attitudes toward affirmative actions for women, mediated by perceived unfairness in the situation of working women, perceived threat to the non-designated group, and feminine self-concept. Implications for research and practice are discussed.

  19. Analyzing individual and group differences in multijoint multiwaveform gait data using the Parafac2 model.

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    Helwig, Nathaniel E; Hong, Sungjin; Bokhari, Ehsan

    2013-01-01

    Locomotion research often involves analyzing multiwaveform data (e.g., velocities, accelerations, etc.) from various body locations (e.g., knees, ankles, etc.) of several subjects. Therefore, some multivariate technique such as principal component analysis is often used to examine interrelationships between the many correlated waveforms. Despite its extensive use in locomotion research, principal component analysis is for two-mode data, whereas locomotion data are typically collected in higher mode form. In this paper, we present the benefits of analyzing four-mode locomotion data (subjects × time × joints × waveforms) using the Parafac2 model, which is a component model designed for analyzing variation in multimode data. Using bilateral hip, knee, and ankle angular displacement, velocity, and acceleration waveforms, we demonstrate Parafac2's ability to produce interpretable components describing (i) the fundamental patterns of variation in lower limb angular kinematics during healthy walking and (ii) the fundamental differences between normal and atypical subjects' multijoint multiwaveform locomotive patterns. Also, we illustrate how Parafac2 makes it possible to determine which waveforms best characterize the individual and/or group differences captured by each component. Our results indicate that different waveforms should be used for different purposes, confirming the need for the holistic analysis of multijoint multiwaveform locomotion data, particularly when investigating atypical motion patterns.

  20. A simple model describes large individual differences in simultaneous colour contrast.

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    Ekroll, Vebjørn; Faul, Franz

    2009-09-01

    We report experimental evidence for substantial individual differences in the susceptibility to simultaneous colour contrast. Interestingly, we found that not only the general amount of colour induction varies across observers, but also the general shape of the curves describing asymmetric matching data. A simple model based on von Kries adaptation and crispening describes the data rather well when we regard its free parameters as observer specific. We argue that the von Kries component reflects the action of a temporal adaptation mechanism, while the crispening component describes the action of the instantaneous, purely spatial mechanism most appropriately labeled simultaneous colour contrast. An interesting consequence of this view is that traditional ideas about the general characteristics of simultaneous contrast must be considered as misleading. According to Kirschmann's 4th law, for instance, the simultaneous contrast effect should increase with increasing saturation of the surround, but crispening predicts the converse. Based on this reasoning, we offer a plausible explanation for the mixed evidence on the validity of Kirschmann's 4th law. We also argue that simultaneous contrast, the crispening effect, Meyer's effect and the gamut expansion effect are just different names for the same basic phenomenon.

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

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    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. Individual differences in Pollyannaism.

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    Matlin, M W; Gawron, V J

    1979-08-01

    The Pollyanna Principle states that people process pleasant information more accurately and efficiently than less pleasant information. This study examined whether different measures of Pollyanna tendencies are correlated with each other. Fourteen measures of Pollyannaism were derived for 133 students. The results showed that subjects who rated themselves as optimistic or happy also showed Pollyannaism on other measures of happiness, believed that the events in their lives were pleasant, gave themselves positive ratings on personality characteristics, recalled pleasant words more often than unpleasant words, supplied more free associations to pleasant stimuli than to unpleasant stimuli, listed pleasant items first, and judged that pleasant words were more frequent in the English language.

  3. Taking individual scaling differences into account by analyzing profile data with the Mixed Assessor Model

    DEFF Research Database (Denmark)

    Brockhoff, Per Bruun; Schlich, Pascal; Skovgaard, Ib

    2015-01-01

    are deduced that include scaling difference in the error term to the proper extent. A meta study of 8619 sensory attributes from 369 sensory profile data sets from SensoBase (www.sensobase.fr) is conducted. In 45.3% of all attributes scaling heterogeneity is present (P-value ...) that properly takes this into account by a simple inclusion of the product averages as a covariate in the modeling and allowing the covariate regression coefficients to depend on the assessor. This gives a more powerful analysis by removing the scaling difference from the error term and proper confidence limits.......9% of the attributes having a product difference P-value in an intermediate range by the traditional approach, the new approach resulted in a clearly more significant result for 42.3% of these cases. Overall, the new approach claimed significant product difference (P-value

  4. Individual Differences, Computers, and Instruction.

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    Ayersman, David J.; Minden, Avril von

    1995-01-01

    Provides a conceptual foundation for the development of hypermedia as an instructional tool for addressing individual differences in learning styles. Highlights include a literature review; computers and instruction; individual differences, computers, and instruction; cognitive controls; cognitive styles and learning; personality types; and future…

  5. Individual Learner Differences in SLA

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    Arabski, Janusz; Wojtaszek, Adam

    2011-01-01

    "Individual Learner Differences in SLA" addresses the apparently insoluble conflict between the unquestionably individual character of the process of second language acquisition/foreign language learning and the institutionalised, often inflexible character of formal instruction in which it takes place. How, then, is success in SLA so prevalent?

  6. Individual Learner Differences in SLA

    Science.gov (United States)

    Arabski, Janusz; Wojtaszek, Adam

    2011-01-01

    "Individual Learner Differences in SLA" addresses the apparently insoluble conflict between the unquestionably individual character of the process of second language acquisition/foreign language learning and the institutionalised, often inflexible character of formal instruction in which it takes place. How, then, is success in SLA so prevalent?

  7. Individual Colorimetric Observer Model.

    Directory of Open Access Journals (Sweden)

    Yuta Asano

    Full Text Available This study proposes a vision model for individual colorimetric observers. The proposed model can be beneficial in many color-critical applications such as color grading and soft proofing to assess ranges of color matches instead of a single average match. We extended the CIE 2006 physiological observer by adding eight additional physiological parameters to model individual color-normal observers. These eight parameters control lens pigment density, macular pigment density, optical densities of L-, M-, and S-cone photopigments, and λmax shifts of L-, M-, and S-cone photopigments. By identifying the variability of each physiological parameter, the model can simulate color matching functions among color-normal populations using Monte Carlo simulation. The variabilities of the eight parameters were identified through two steps. In the first step, extensive reviews of past studies were performed for each of the eight physiological parameters. In the second step, the obtained variabilities were scaled to fit a color matching dataset. The model was validated using three different datasets: traditional color matching, applied color matching, and Rayleigh matches.

  8. Individual Differences in Planning Processes.

    Science.gov (United States)

    1980-06-01

    just finished your piano lesson at the music school and have many errands to do before going home. Your 2-week vacation starts next week and you still...satisfactory plan. IMPLICATIONS FOR INDIVIDUAL DIFFERENCES While the OPM is not a theory of individual differences, it pro- vides a framework for studying...Errand List music school 82 plan vacation at travel agency 26 buy Spanish phrasebook at bookstore 14, 86, 32 buy new outfit at one of the fine clothes

  9. Individual differences in cognitive arithmetic.

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    Geary, D C; Widaman, K F

    1987-06-01

    Relations factor was found. Results of the structural modeling support the conclusion that information retrieval from a network of arithmetic facts and execution of the carry operation are elementary component processes involved uniquely in the mental solving of arithmetic problems. Furthermore, individual differences in the speed of executing these two elementary component processes appear to underlie individual differences on ability measures that traditionally span the Numerical Facility factor.(ABSTRACT TRUNCATED AT 400 WORDS)

  10. Modelling dopaminergic and other processes involved in learning from reward prediction error: Contributions from an individual differences perspective

    Directory of Open Access Journals (Sweden)

    Alan David Pickering

    2014-09-01

    Full Text Available Phasic firing changes of midbrain dopamine neurons have been widely characterised as reflecting a reward prediction error (RPE. Major personality traits (e.g. extraversion have been linked to inter-individual variations in dopaminergic neurotransmission. Consistent with these two claims, recent research (Smillie, Cooper, & Pickering, 2011; Cooper, Duke, Pickering, & Smillie, 2014 found that extraverts exhibited larger RPEs than introverts, as reflected in feedback related negativity (FRN effects in EEG recordings. Using an established, biologically-localised RPE computational model, we successfully simulated dopaminergic cell firing changes which are thought to modulate the FRN. We introduced simulated individual differences into the model: parameters were systematically varied, with stable values for each simulated individual. We explored whether a model parameter might be responsible for the observed covariance between extraversion and the FRN changes in real data, and argued that a parameter is a plausible source of such covariance if parameter variance, across simulated individuals, correlated almost perfectly with the size of the simulated dopaminergic FRN modulation, and created as much variance as possible in this simulated output. Several model parameters met these criteria, while others did not. In particular, variations in the strength of connections carrying excitatory reward drive inputs to midbrain dopaminergic cells were considered plausible candidates, along with variations in a parameter which scales the effects of dopamine cell firing bursts on synaptic modification in ventral striatum. We suggest possible neurotransmitter mechanisms underpinning these model parameters. Finally, the limitations and possible extensions of our approach are discussed.

  11. Modeling dopaminergic and other processes involved in learning from reward prediction error: contributions from an individual differences perspective.

    Science.gov (United States)

    Pickering, Alan D; Pesola, Francesca

    2014-01-01

    Phasic firing changes of midbrain dopamine neurons have been widely characterized as reflecting a reward prediction error (RPE). Major personality traits (e.g., extraversion) have been linked to inter-individual variations in dopaminergic neurotransmission. Consistent with these two claims, recent research (Smillie et al., 2011; Cooper et al., 2014) found that extraverts exhibited larger RPEs than introverts, as reflected in feedback related negativity (FRN) effects in EEG recordings. Using an established, biologically-localized RPE computational model, we successfully simulated dopaminergic cell firing changes which are thought to modulate the FRN. We introduced simulated individual differences into the model: parameters were systematically varied, with stable values for each simulated individual. We explored whether a model parameter might be responsible for the observed covariance between extraversion and the FRN changes in real data, and argued that a parameter is a plausible source of such covariance if parameter variance, across simulated individuals, correlated almost perfectly with the size of the simulated dopaminergic FRN modulation, and created as much variance as possible in this simulated output. Several model parameters met these criteria, while others did not. In particular, variations in the strength of connections carrying excitatory reward drive inputs to midbrain dopaminergic cells were considered plausible candidates, along with variations in a parameter which scales the effects of dopamine cell firing bursts on synaptic modification in ventral striatum. We suggest possible neurotransmitter mechanisms underpinning these model parameters. Finally, the limitations and possible extensions of our general approach are discussed.

  12. 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.

  13. Individual differences in distance perception.

    Science.gov (United States)

    Jackson, Russell E

    2009-05-07

    Distance perception is among the most pervasive mental phenomena and the oldest research topics in behavioural science. However, we do not understand well the most pervasive finding of distance perception research, that of large individual differences. There are large individual differences in acrophobia (fear of heights), which we commonly assume consists of an abnormal fear of stimuli perceived normally. Evolved navigation theory (ENT) instead suggests that acrophobia consists of a more normal fear of stimuli perceived abnormally. ENT suggests that distance perception individual differences produce major components of acrophobia. Acrophobia tested over a broad range in the present study predicted large individual differences in distance estimation of surfaces that could produce falls. This fear of heights correlated positively with distance estimates of a vertical surface-even among non-acrophobic individuals at no risk of falling and without knowledge of being tested for acrophobia. Acrophobia score predicted magnitude of the descent illusion, which is thought to reflect the risk of falling. These data hold important implications in environmental navigation, clinical aetiology and the evolution of visual systems.

  14. Individual Differences in Response to Automation: The Five Factor Model of Personality

    Science.gov (United States)

    Szalma, James L.; Taylor, Grant S.

    2011-01-01

    This study examined the relationship of operator personality (Five Factor Model) and characteristics of the task and of adaptive automation (reliability and adaptiveness--whether the automation was well-matched to changes in task demand) to operator performance, workload, stress, and coping. This represents the first investigation of how the Five…

  15. 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…

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

    Science.gov (United States)

    Wegner, Rhiana; Abbey, Antonia

    2016-05-01

    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 impersonal sexual orientation were proximal predictors of men's misperception of women's sexual intent. Additionally, narcissism was indirectly related to men's misperception through hostile masculinity. Impulsive sensation-seeking was directly and indirectly related to men's misperceptions through impersonal sexual orientation. Although there was a bivariate relationship between alcohol consumption and misperception, this relationship was not significant in the path model. Overall, these findings demonstrate the importance of considering how personality traits increase the risk for misperception.

  17. Origin of Individual Differences in Importance Attached to Work: A Model and a Contribution to Its Evaluation.

    Science.gov (United States)

    Sverko, Branimir

    1989-01-01

    Tested model proposing that importance of work for individual depends on individual's perception of possibilities for attainment of personal salient work values through working. Responses from 1,872 high school students, 348 university students, and 344 adults to measures on importance of 20 work values, perceptions of their attainment…

  18. 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, Saba; Struthers, Ward; van Oudenhoven, Jan Pieter

    2009-01-01

    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

  19. 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

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

    Directory of Open Access Journals (Sweden)

    Antonio eArmario

    2013-11-01

    Full Text Available 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 behavioural 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 behaviour in rodents.

  1. Empathizing: neurocognitive developmental mechanisms and individual differences.

    Science.gov (United States)

    Chakrabarti, Bhismadev; Baron-Cohen, Simon

    2006-01-01

    This chapter reviews the Mindreading System model encompassing four neurocognitive mechanisms (ID, EDD, SAM, and ToMM) before reviewing the revised empathizing model encompassing two new neurocognitive mechanisms (TED and TESS). It is argued that the empathizing model is more comprehensive because it entails perception, interpretation, and affective responses to other agents. Sex differences in empathy (female advantage) are then reviewed, as a clear example of individual differences in empathy. This leads into an illustration of individual differences using the Empathy Quotient (EQ). Finally, the neuroimaging literature in relation to each of the neurocognitive mechanisms is briefly summarized and a new study is described that tests if different brain regions respond to the perception of different facial expressions of emotion, as a function of the observer's EQ.

  2. The Individual Differences Tradition in Counseling Psychology.

    Science.gov (United States)

    Dawis, Rene V.

    1992-01-01

    Traces historical development from individual differences psychology through psychological testing, vocational counseling, and student personnel work, to counseling psychology. Describes individual differences tradition in counseling psychology research and practice. Discusses how individual differences psychology has influenced counseling…

  3. 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…

  4. 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

  5. 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

  6. 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.

  7. Understanding the effects of different HIV transmission models in individual-based microsimulation of HIV epidemic dynamics in people who inject drugs.

    Science.gov (United States)

    Monteiro, J F G; Escudero, D J; Weinreb, C; Flanigan, T; Galea, S; Friedman, S R; Marshall, B D L

    2016-06-01

    We investigated how different models of HIV transmission, and assumptions regarding the distribution of unprotected sex and syringe-sharing events ('risk acts'), affect quantitative understanding of HIV transmission process in people who inject drugs (PWID). The individual-based model simulated HIV transmission in a dynamic sexual and injecting network representing New York City. We constructed four HIV transmission models: model 1, constant probabilities; model 2, random number of sexual and parenteral acts; model 3, viral load individual assigned; and model 4, two groups of partnerships (low and high risk). Overall, models with less heterogeneity were more sensitive to changes in numbers risk acts, producing HIV incidence up to four times higher than that empirically observed. Although all models overestimated HIV incidence, micro-simulations with greater heterogeneity in the HIV transmission modelling process produced more robust results and better reproduced empirical epidemic dynamics.

  8. Cognitive world: Neuropsychology of individual differences.

    Science.gov (United States)

    Ardila, Alfredo; Rosselli, Monica

    2016-09-20

    It is proposed that depending upon the specific pattern of cognitive abilities, each individual lives in an idiosyncratic "cognitive world." Brain pathology can be associated with some disturbed abilities, and frequently experiential changes (i.e., how the world is understood) are observed. Because these patients often are aware of their intellectual changes, they may represent excellent models to illustrate the diversity of cognitive interpretations an individual can have about the surrounding environmental conditions. Four neuropsychology cases are presented to illustrate this point: (a) prosopagnosia associated with spatial agnosia; (b) Gerstmann's syndrome; (c) dysexecutive syndrome due to a head injury; and, (d) patient with Capgras' syndrome associated with a left temporal cyst. It is further emphasized that non-brain damaged people present an enormous-but usually overlooked-dispersion in different cognitive domains, resulting in specific and idiosyncratic patterns of cognitive abilities. It is concluded that the concept of "cognitive world" in neuropsychology can parallel the concept of "perceptual world" introduced by von Uexküll in biology, which assumes that different animal species live in idiosyncratic perceptual worlds, available and knowable by the differences in their sensory system abilities. That is, different individuals live in idiosyncratic cognitive worlds, owing to their differences in cognitive abilities.

  9. 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

    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......, by means of LCA-modelling, aims at comparing the environmental performance of three major management options (landfilling, recycling and incineration or composting) for a number of individual waste fractions. The landfilling option is here approached comprehensively, accounting for all technical...... 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...

  10. 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.

  11. Understanding burnout according to individual differences: ongoing explanatory power evaluation of two models for measuring burnout types

    Directory of Open Access Journals (Sweden)

    Montero-Marín Jesús

    2012-10-01

    Full Text Available Abstract Background The classic determination of burnout is by means of the dimensions exhaustion, cynicism and inefficacy. A new definition of the syndrome is based on clinical subtypes, consisting of “frenetic” (involved, ambitious, overloaded, “underchallenged” (indifferent, bored, with lack of personal development and “worn-out” (neglectful, unacknowledged, with little control. The dimensions of overload, lack of development and neglect form a shortened version of this perspective. The aims of this study were to estimate and to compare the explanatory power of both typological models, short and long, with the standard measurement. Methods This was a cross-sectional survey with a randomly sample of university employees (n=409. Multivariate linear regression models were constructed between the “Maslach Burnout Inventory General Survey” (MBI-GS dimensions, as dependent variables, and the “Burnout Clinical Subtype Questionnaire” (BCSQ-36 and BCSQ-12 dimensions, as independent variables. Results The BCSQ-36 subscales together explained 53% of ‘exhaustion’ (p Conclusions Both BCSQ-36 and BCSQ-12 demonstrate great explanatory power over the standard MBI-GS, while offering a useful characterization of the syndrome for the evaluation and design of interventions tailored to the characteristics of each individual. The BCSQ-36 may be very useful in mental health services, given that it provides a good deal of information, while the BCSQ-12 could be used as a screening measure in primary care consultations owing to its simplicity and functional nature.

  12. Contributions of Individual Differences and Contextual Variables to Reading Achievement of English Language Learners: An Empirical Investigation Using Hierarchical Linear Modeling

    Science.gov (United States)

    Ardasheva, Yuliya; Tretter, Thomas R.

    2013-01-01

    This nonexperimental study explored the relationships among individual differences, contextual variables, and reading achievement of English language learners (ELLs) in one large urban school district in the United States. The sample comprised 840 students in Grades 3-8 and 10 nested within 37 schools. Hierarchical linear modeling results indicate…

  13. Individual Differences in Participations of a Brand Community: A Validation of the Goal-Directed Behavior Model

    Directory of Open Access Journals (Sweden)

    Badri Munir Sukoco

    2011-10-01

    Full Text Available Previous studies have been neglected the behavior of the owners who are non-members when discussing brand community (BC, even though they are substantially larger. This study purposely discuss what are the differences between the two by using model of goal directed behavior (MGB and uses the findings as a way to recruit non-members in BC activities. This study also proposes some refinements to the original concept of MGB. This survey-based study, conducted with 201 active members and 226 non-members of a motor club in Indonesia, employs structural equation modeling methodology which supports the proposed model. The findings suggest that non-members have a stronger effect of positive anticipated emotions on attitude and desire to participate, which could be the starting point for marketers to recruit them. While for non-members, the perceived behavioral control and attitude toward BC activities have greater effects. The findings and discussion lead to some managerial and research implications.

  14. 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…

  15. Experimental analysis of individual differences and personality

    OpenAIRE

    Harzem, Peter

    1984-01-01

    In psychological studies individual differences that result in variability in data and thus mask the effects under investigation have been reduced or eliminated in two ways: (1) through the use of large numbers of subjects and statistical manipulations, or (2) through extensive and controlled studies of individual subjects. The latter, behavior-analytic, method is scientifically better because it permits identification of the variables that result in individual differences. This paper advocat...

  16. Genetic parameters of different measures of cheese yield and milk nutrient recovery from an individual model cheese-manufacturing process.

    Science.gov (United States)

    Bittante, G; Cipolat-Gotet, C; Cecchinato, A

    2013-01-01

    Cheese yield (CY) is an important technological trait in the dairy industry, and the objective of this study was to estimate the genetic parameters of cheese yield in a dairy cattle population using an individual model-cheese production procedure. A total of 1,167 Brown Swiss cows belonging to 85 herds were sampled once (a maximum of 15 cows were sampled per herd on a single test day, 1 or 2 herds per week). From each cow, 1,500 mL of milk was processed according to the following steps: milk sampling and heating, culture addition, rennet addition, gelation-time recording, curd cutting, whey draining and sampling, wheel formation, pressing, salting in brine, weighing, and cheese sampling. The compositions of individual milk, whey, and curd samples were determined. Three measures of percentage cheese yield (%CY) were calculated: %CY(CURD), %CY(SOLIDS), and %CY(WATER), which represented the ratios between the weight of fresh curd, the total solids of the curd, and the water content of the curd, respectively, and the weight of the milk processed. In addition, 3 measures of daily cheese yield (dCY, kg/d) were defined, considering the daily milk yield. Three measures of nutrient recovery (REC) were computed: REC(FAT), REC(PROTEIN), and REC(SOLIDS), which represented the ratio between the weights of the fat, protein, and total solids in the curd, respectively, and the corresponding nutrient in the milk. Energy recovery, REC(ENERGY), represented the energy content of the cheese versus that in the milk. For statistical analysis, a Bayesian animal model was implemented via Gibbs sampling. The effects of parity (1 to ≥4), days in milk (6 classes), and laboratory vat (15 vats) were assigned flat priors; those of herd-test-date, animal, and residual were given Gaussian prior distributions. Intra-herd heritability estimates of %CY(CURD), %CY(SOLIDS), and %CY(WATER) ranged from 0.224 to 0.267; these were larger than the estimates obtained for milk yield (0.182) and milk fat

  17. 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 contrib

  18. An ontogenetic perspective on individual differences.

    Science.gov (United States)

    Senner, Nathan R; Conklin, Jesse R; Piersma, Theunis

    2015-09-07

    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 contribute separately and synergistically to observed variation in functional traits. We propose a conceptual framework based on a developmental view of life-history variation, linking each ontogenetic stage with the types of individual differences originating during that period. In our view, the salient differences among these types are encapsulated by three key criteria: timing of onset, when fitness consequences are realized, and potential for reversibility. To fill a critical gap in this framework, we formulate a new term to refer to individual differences generated during adulthood-reversible state effects. We define these as 'reversible changes in a functional trait resulting from life-history trade-offs during adulthood that affect fitness', highlighting how the adult phenotype can be repeatedly altered in response to environmental variation. Defining individual differences in terms of trade-offs allows explicit predictions regarding when and where fitness consequences should be expected. Moreover, viewing individual differences in a developmental context highlights how different processes can work in concert to shape phenotype and fitness, and lays a foundation for research linking individual differences to ecological and evolutionary theory.

  19. 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

  20. Impact of different wood chip species (oak, acacia and cherry on evolution of individual anthocyanins, chromatic characteristics and antioxidant capacity in model wine solutions

    Directory of Open Access Journals (Sweden)

    Jordão António M.

    2017-01-01

    Full Text Available The aim of present work was to investigate the impact of different oak (Q. alba, Q. robur and Q. pyrenaica, acacia and cherry wood chips on evolution of individual anthocyanin content, chromatic characteristics and antioxidant capacity by the use of model wine solutions. According to the results obtained, model wine solutions containing acacia and especially cherry wood extracts showed more evident changes of individual anthocyanin composition, especially due to the formation of large number of new direct condensation anthocyanins, than model wines with oak extracts. These results were accompanied also by a higher color degradation and a lower antioxidant potential of solutions containing the different wood chip extract species, compared with solutions containing only anthocyanin alone. This research contributes to a better knowledge about the color evolution of red wines when they are aging in contact with new alternative wood species, especially acacia and cherry.

  1. 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

  2. INDIVIDUAL DIFFERENCES IN THE IRRELEVANT SPEECH EFFECT

    National Research Council Canada - National Science Library

    MIYAHARA, Michiko; GOSHIKI, Toru

    2004-01-01

    This study examines the effect of irrelevant speech effect on a serial recall task, focusing on individual difference indexes, such as introversion/extraversion, field dependence/independence, and reading span...

  3. 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).

  4. 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

  5. A Mathematical Model of the Evolution of Individual Differences in Developmental Plasticity Arising through Parental Bet-Hedging

    Science.gov (United States)

    Frankenhuis, Willem E.; Panchanathan, Karthik; Belsky, Jay

    2016-01-01

    Children vary in the extent to which their development is shaped by particular experiences (e.g. maltreatment, social support). This variation raises a question: Is there no single level of plasticity that maximizes biological fitness? One influential hypothesis states that when different levels of plasticity are optimal in different environmental…

  6. Linking life history theory, environmental setting, and individual-based modeling to compare responses of different fish species to environmental change

    Energy Technology Data Exchange (ETDEWEB)

    Van Winkle, W.; Rose, K.A.; Winemiller, K.O.; DeAngelis, D.L.; Christensen, S.W. (Oak Ridge National Lab., TN (United States)); Otto, R.G. (R.G. Otto Associates, Vienna, MD (United States)); Shuter, B.J. (Ontario Ministry of Natural Resurces, Onatario (Canada))

    1993-05-01

    We link life history theory, environmental setting, and individual-based modeling to compare the responses of two fish species to environmental change. Life history theory provides the framework for selecting representative species, and in combination with information on important environmental characteristics, it provides the framework for predicting the results of model simulations. Individual-based modeling offers a promising tool for integrating and extrapolating our mechanistic understanding of reproduction, growth, and mortality at the individual level to population-level responses such as size-frequency distributions and indices of year-class strength. Based on the trade-offs between life history characteristics of striped bass Morone saxatilis and smallmouth bass Micropterus dolomieu and differences in their respective environments, we predicted that young-of-year smallmouth bass are likely to demonstrate a greater compensatory change in growth and mortality than young-of-year striped bass in response to changes in density of early life stages and turnover rates of zooplankton prey. We tested this prediction with a simulation experiment. The pattern of model results was consistent with our expectations: by the end of the first growing season, compensatory changes in length and abundance of juveniles were more pronounced for smallmouth bass than for striped bass. The results also highlighted the dependence of model predictions on the interplay between density of larvae and juveniles and characteristics of their zooplankton prey.

  7. A mathematical model of the evolution of individual differences in developmental plasticity arising through parental bet-hedging

    NARCIS (Netherlands)

    Frankenhuis, W.E.; Panchanathan, K.; Belsky, J.

    2016-01-01

    Children vary in the extent to which their development is shaped by particular experiences (e.g. maltreatment, social support). This variation raises a question: Is there no single level of plasticity that maximizes biological fitness? One influential hypothesis states that when different levels of

  8. A General Theoretical Integrative Model of Individual Differences in Interests, Abilities, Personality Traits, and Academic and Occupational Achievement: A Commentary on Four Recent Articles.

    Science.gov (United States)

    Schmidt, Frank L

    2014-03-01

    This commentary integrates the contents of four recent articles on individual differences (Nye, Su, Rounds, & Drasgow, 2012; Schmidt, 2011; Valla & Ceci, 2011; von Stumm, Hell, & Chamorro-Premuzic, 2011) in a causal theoretical model. In this model, introversion and fluid intelligence cause interest in general learning (intellectual curiosity), which in turn is a major cause of crystallized intelligence. Certain specific interests and fluid intelligence also contribute to crystallized intelligence. Prenatal testosterone hormone conditioning is postulated to cause sex differences in certain specific interests but not in others. Crystallized intelligence, specific interests, and the personality trait of conscientiousness cause adult academic and occupational performance, whereas crystallized intelligence is the main cause of good mental functioning at older ages. Research is presented supporting each link in the model.

  9. 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.

  10. 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...

  11. Individual cortical current density reconstructions of the semantic N400 effect: using a generalized minimum norm model with different constraints (L1 and L2 norm).

    Science.gov (United States)

    Haan, H; Streb, J; Bien, S; Rösler, F

    2000-11-01

    Event-related brain potentials were recorded to study whether verbs and nouns activate topographically distinct cortical generators. Fifteen subjects performed a primed lexical decision task with verb/verb and noun/noun pairs. The relatedness between prime and target items was varied in three steps (unrelated, moderately, and strongly related) and the EEG was recorded from 124 scalp electrodes. The topography of cortical sources of the N400 effect was evaluated by standardized differences scores and by cortical current source estimates which were constrained by the individual MRI-determined cortex anatomy. A behavioral priming effect and a substantial N400 effect was found for both word categories. However, the topography of the grand average N400 effect of verbs and nouns did not differ, neither for raw nor for standardized amplitudes. Cortical current source estimates of the N400 effect revealed a very broad and scattered distribution of active locations with pronounced interindividual differences. Cortical current source estimates obtained with the L1-norm and L2-norm model, respectively, differed in the distribution of sources over the cortex but converged on the same "hot spots." The data give no indication that the N400 effect is generated by word category-specific networks which have a different topography. The marked individual differences are discussed with respect to the involved processes and the current source estimation procedures.

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

    Science.gov (United States)

    2008-04-01

    better performance on written reports. 7.4 Team Roles The team roles required to be assumed by individuals also influence the effects of individual...differences. Stewart, et al. (2005) proposed such a model in which the individual difference-team outcome relation which is affected by team roles . While...into team level role configurations, those task (i.e., fact gathering, information processing, problem solving) and team roles (i.e., cooperation

  13. Individual Differences in Dual Task Performance.

    Science.gov (United States)

    1981-06-10

    others (LansMan, 1978’ Palmer, MacLeod, Hunt, 9 Davidson, Note 1 Perfetti & Lesgold, 1977) have found virtuallq no relationship between rote memorj and...2, 326-336. Perfetti , C*A., & Lesgold, A.M. Discourse comprehension and sources of individual differences. In M.A. Just e P.A. Carpenter (Eds

  14. Working Memory Capacity: An Individual Differences Approach.

    Science.gov (United States)

    1988-02-11

    level tasks as reading comprehension ( Perfetti & Lesgold, 1977) or even the amount of Information estimated to be represented in primary or secondary...Prentice-Hall. II ~ Perfetti , C.A. &Lesgold, A.M. (1977). Discourse comprehension and sources of individual differences. In M. A. Just & P. A. Carpenter

  15. 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…

  16. 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…

  17. Trends in the psychophysiology of individual differences.

    Science.gov (United States)

    Mecacci, L

    1976-01-01

    Pavlov's typology of higher nervous activity was the first systematic approach to the psychophysiology of individual differences. Pavlov's theory has been further developed by Teplov, Nebylitsyn and their pupils in the Institute of Psychology in Moscow. In particular, Nebylitsyn has delineated a new property of the nervous system and has shown that it is different from strength of nervous system. In the Western research context we can compare the relationship between these two parameters to that between arousal and conditioning level. Eysenck's theory of the physiological bases of extraversion/introversion is discussed in relation to Nebylitsyn's theses and Gray's conception of arousability. Finally, it is suggested that future work in the psychophysiology of individual differences should stress the study of the ontogenetic development of the physiological variables.

  18. 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

  19. 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.

  20. Hazard personality profiles and individual differences

    Energy Technology Data Exchange (ETDEWEB)

    Barnett, J.; Breakwell, G.M. [Surrey Univ., Guildford (United Kingdom). Dept. of Psychology

    1998-07-01

    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

  1. Individual Differences in Music Reward Experiences

    OpenAIRE

    Mas-Herrero, E.; Marco Pallarés, Josep; Lorenzo-Seva, U.; Zatorre, R.; Rodriguez-Fornells, A.

    2013-01-01

    Music is one of the most pleasant human experiences, even though it has no direct biological advantage. However little is known about individual differences in how people experience reward in music-related activities. The goal of the present study was to describe the main facets of music experience that could explain the variance observed in how people experience reward associated with music. To this end we developed the Barcelona Music Reward Questionnaire (BMRQ), which was administrated to ...

  2. Individual Differences in Secondary Task Performance.

    Science.gov (United States)

    1980-09-01

    task similar to that used by Atkinson and Shiffrin (1968). The spatial task in- volved holding in memory a random pattern of plus signs. In all cases...may serve to attenuate the easy-to-hard correlation. I *1,~ __ __ _ Secondary Task Performance 33 References Atkinson , R. C., & Shiffrin , R. M. Human...aIde if nec.eaar, and Identify by block number) ability, attention, dual task, information processing, individual differences memory , secondary task

  3. 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

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

    DEFF Research Database (Denmark)

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

    2016-01-01

    It is well-established that hearing loss does not only lead to a reduction of hearing sensitivity. Large individual differences are typically observed among listeners with hearing impairment in a wide range of suprathreshold auditory measures. In many cases, audiometric thresholds cannot fully...... 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...

  5. The rostral prefrontal cortex underlies individual differences in working memory capacity: An approach from the hierarchical model of the cognitive control.

    Science.gov (United States)

    Minamoto, Takehiro; Yaoi, Ken; Osaka, Mariko; Osaka, Naoyuki

    2015-10-01

    Neuroimaging and behavioral evidence has suggested that the lateral prefrontal cortex is involved in individual differences in working memory capacity (WMC). However, few studies have localized the neural structures that differentiate high and low WMC individuals, considering the functional architecture of the prefrontal cortex. The present study aimed to identify a frontal region that underlies individual differences from the perspective of the hierarchical architecture of the frontal cortex. By manipulating an episodic factor of cognitive control (control in selecting an appropriate task set according to a temporal context) and using a parametric modulation analysis, we found that both high- and low- WMC individuals have similar activation patterns in the premotor cortex (BA6, 8), caudal prefrontal cortex (BA44, 45), and frontopolar cortex (BA10, 11), but differed in the rostral part of the prefrontal cortex (BA46/47); high WMC individuals showed greater activation in the higher episodic control condition, whereas low WMC individuals showed reduced activation when episodic control was required. Similar patterns of activation were found in the right inferior parietal and middle/inferior temporal cortices. These results indicate that the rostral prefrontal cortex, which supports episodic cognitive control, possibly by sending a weighting signal toward the inferior parietal and middle/inferior temporal cortices that modulate saliency and sensory processing, underlies individual differences in WMC. Episodic control account, which considers the organization of the prefrontal cortex, fits well with previous findings of individual differences in WMC.

  6. Subcortical correlates of individual differences in aptitude.

    Directory of Open Access Journals (Sweden)

    Rex E Jung

    Full Text Available The study of individual differences encompasses broad constructs including intelligence, creativity, and personality. However, substantially less research is devoted to the study of specific aptitudes in spite of their importance to educational, occupational, and avocational success. We sought to determine subcortical brain structural correlates of several broad aptitudes including Math, Vocabulary, Foresight, Paper Folding, and Inductive Reasoning in a large (N = 107, healthy, young (age range  = 16-29 cohort. Subcortical volumes were measured using an automated technique (FreeSurfer across structures including bilateral caudate, putamen, globus pallidus, thalamus, nucleus accumbens, hippocampus, amygdala, and five equal regions of the corpus callosum. We found that performance on measures of each aptitude was predicted by different subcortical structures: Math--higher right nucleus accumbens volume; Vocabulary--higher left hippocampus volume; Paper Folding--higher right thalamus volume; Foresight--lower right thalamus and higher mid anterior corpus callosum volume; Inductive Reasoning--higher mid anterior corpus callosum volume. Our results support general findings, within the cognitive neurosciences, showing lateralization of structure-function relationships, as well as more specific relationships between individual structures (e.g., left hippocampus and functions relevant to particular aptitudes (e.g., Vocabulary.

  7. Subcortical correlates of individual differences in aptitude.

    Science.gov (United States)

    Jung, Rex E; Ryman, Sephira G; Vakhtin, Andrei A; Carrasco, Jessica; Wertz, Chris; Flores, Ranee A

    2014-01-01

    The study of individual differences encompasses broad constructs including intelligence, creativity, and personality. However, substantially less research is devoted to the study of specific aptitudes in spite of their importance to educational, occupational, and avocational success. We sought to determine subcortical brain structural correlates of several broad aptitudes including Math, Vocabulary, Foresight, Paper Folding, and Inductive Reasoning in a large (N = 107), healthy, young (age range  = 16-29) cohort. Subcortical volumes were measured using an automated technique (FreeSurfer) across structures including bilateral caudate, putamen, globus pallidus, thalamus, nucleus accumbens, hippocampus, amygdala, and five equal regions of the corpus callosum. We found that performance on measures of each aptitude was predicted by different subcortical structures: Math--higher right nucleus accumbens volume; Vocabulary--higher left hippocampus volume; Paper Folding--higher right thalamus volume; Foresight--lower right thalamus and higher mid anterior corpus callosum volume; Inductive Reasoning--higher mid anterior corpus callosum volume. Our results support general findings, within the cognitive neurosciences, showing lateralization of structure-function relationships, as well as more specific relationships between individual structures (e.g., left hippocampus) and functions relevant to particular aptitudes (e.g., Vocabulary).

  8. Individual differences in activity levels in zebrafish (Danio rerio)

    Science.gov (United States)

    Tran, Steven; Gerlai, Robert

    2013-01-01

    Individual differences and variation in behavioural responses have been identified in many animal species. These differences may be the result of genetic or environmental factors or the interaction between them. Analysis of individual differences in behaviour may be important for many reasons. The zebrafish is a powerful model organism that is rapidly gaining popularity in behavioural brain research. However, individual differences have rarely been explored in zebrafish although significant variation in their performance has been reported. In the current study we identified individual differences in activity levels of zebrafish using a genetically heterogeneous population. Groups of zebrafish classified as high, medium, or low activity performers demonstrated consistent activity levels over a period of 7 days, and also in a subsequent open field task, suggesting stable individual differences as opposed to stochastic variation among subjects. We also uncovered a sex dependent relationship between behavioural measures. Female zebrafish in the high activity group preferred the top portion of the tank, whereas low activity females preferred the lower portion but males did not show such a relationship. The relationship between these two behaviours in females implies the potential existence of a behavioural syndrome persisting between contexts. Furthermore, females demonstrated a higher level of consistency in their behaviour as compared to males, and the behavioural differences were found to be independent of both body size and weight of the tested subjects. The identification of individual differences in activity levels in zebrafish will allow the investigation of underlying genetic and/or environmental underpinnings. PMID:24084583

  9. 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.

  10. Individual differences in behavioral and cardiovascular reactivity to emotive stimuli and their relationship to cognitive flexibility in a primate model of trait anxiety.

    Directory of Open Access Journals (Sweden)

    Yoshiro eShiba

    2014-04-01

    Full Text Available High trait anxiety is a risk factor for the development of anxiety disorders. Like the disorders themselves high trait anxiety has marked phenotypic variation at the level of symptomatology and neural circuits, suggesting that there may be different symptoms and distinct neural circuits associated with risk for these disorders. To address these issues, it is essential to develop reliable animal models of trait anxiety in a non-human primate whose brain bears structural and functional similarity to humans. The present study investigated individual variation in responsivity to fearful and anxiety provoking stimuli in the common marmoset monkey. Seven out of 27 animals failed to display discriminative, conditioned cardiovascular and behavioral responses on an auditory fear discrimination task, similar to that seen in high anxious humans and rodents. Their heightened emotionality to a rubber snake was consistent with the hypothesis that they were high in trait-like anxiety. Evidence for phenotypic variation in the high anxiety group was provided by the finding that discrimination failure was predicted early in conditioning by either hyper-vigilant scanning to the cues or a reduction in blood pressure to the context, i.e. test apparatus. Given that high trait anxiety in humans can be associated with altered prefrontal cognitive functioning and previously we implicated the marmoset anterior orbitofrontal (antOFC and ventrolateral prefrontal cortex (vlPFC in negative emotion regulation, we also tested the marmosets on two tests of cognitive flexibility differentially dependent on these two regions. While the high anxious group did not differ overall in their perseverative performance, the two distinct phenotypes were differentially correlated with reduced perseverative responding on the OFC- and vlPFC-dependent flexibility tests. Together, this study provides a new model of trait anxiety in marmosets amenable to analysis of phenotypic variation and

  11. The mysterious cognitive abilities of bees: why models of visual processing need to consider experience and individual differences in animal performance.

    Science.gov (United States)

    Dyer, Adrian G

    2012-02-01

    Vision is one of the most important modalities for the remote perception of biologically important stimuli. Insects like honeybees and bumblebees use their colour and spatial vision to solve tasks, such as navigation, or to recognise rewarding flowers during foraging. Bee vision is one of the most intensively studied animal visual systems, and several models have been developed to describe its function. These models have largely assumed that bee vision is determined by mechanistic hard-wired circuits, with little or no consideration for behavioural plasticity or cognitive factors. However, recent work on both bee colour vision and spatial vision suggests that cognitive factors are indeed a very significant factor in determining what a bee sees. Individual bumblebees trade-off speed for accuracy, and will decide on which criteria to prioritise depending upon contextual information. With continued visual experience, honeybees can learn to use non-elemental processing, including configural mechanisms and rule learning, and can access top-down information to enhance learning of sophisticated, novel visual tasks. Honeybees can learn delayed-matching-to-sample tasks and the rules governing this decision making, and even transfer learned rules between different sensory modalities. Finally, bees can learn complex categorisation tasks and display numerical processing abilities for numbers up to and including four. Taken together, this evidence suggests that bees do have a capacity for sophisticated visual behaviours that fit a definition for cognition, and thus simple elemental models of bee vision need to take account of how a variety of factors may influence the type of results one may gain from animal behaviour experiments.

  12. 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.

  13. Developmental Changes and Individual Differences in Young Children's Moral Judgments

    Science.gov (United States)

    Smetana, Judith G.; Rote, Wendy M.; Jambon, Marc; Tasopoulos-Chan, Marina; Villalobos, Myriam; Comer, Jessamy

    2012-01-01

    Developmental trajectories and individual differences in 70 American middle-income 2.5- to 4-year olds' moral judgments were examined 3 times across 1 year using latent growth modeling. At Wave 1, children distinguished hypothetical moral from conventional transgressions on all criteria, but only older preschoolers did so when rating deserved…

  14. Developmental Changes and Individual Differences in Young Children's Moral Judgments

    Science.gov (United States)

    Smetana, Judith G.; Rote, Wendy M.; Jambon, Marc; Tasopoulos-Chan, Marina; Villalobos, Myriam; Comer, Jessamy

    2012-01-01

    Developmental trajectories and individual differences in 70 American middle-income 2.5- to 4-year olds' moral judgments were examined 3 times across 1 year using latent growth modeling. At Wave 1, children distinguished hypothetical moral from conventional transgressions on all criteria, but only older preschoolers did so when rating deserved…

  15. Women’s Sexuality: Behaviors, Responses, and Individual Differences

    OpenAIRE

    Andersen, Barbara L.; Cyranowski, Jill M.

    1995-01-01

    Classic and contemporary approaches to the assessment of female sexuality are discussed. General approaches, assessment strategies, and models of female sexuality are organized within the conceptual domains of sexual behaviors, sexual responses (desire, excitement, orgasm, and resolution), and individual differences, including general and sex-specific personality models. Where applicable, important trends and relationships are highlighted in the literature with both existing reports and previ...

  16. Individual Influence on Model Selection

    Science.gov (United States)

    Sterba, Sonya K.; Pek, Jolynn

    2012-01-01

    Researchers in psychology are increasingly using model selection strategies to decide among competing models, rather than evaluating the fit of a given model in isolation. However, such interest in model selection outpaces an awareness that one or a few cases can have disproportionate impact on the model ranking. Though case influence on the fit…

  17. 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…

  18. Human Individual Differences in Military Systems

    Science.gov (United States)

    1983-04-01

    experience, and literacy on job performance; Summary of HumRRO work units UTILITY and REALISTIC (Tech. Rep. 71-1). Alexandria, VA: Human Resources...Williams, R. J., & Rimland, B. Individuality. In Encyclopedia of Psychiatry, Neurology, and Psychoanalysis . New York: Van Nostrand, 1977. 26

  19. 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.

  20. 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

  1. Developmental and Individual Differences in Chinese Writing

    Science.gov (United States)

    Guan, Connie Qun; Ye, Feifei; Wagner, Richard K.; Meng, Wanjin

    2013-01-01

    The goal of the present study was to examine the generalizability of a model of the underlying dimensions of written composition across writing systems (Chinese Mandarin vs. English) and level of writing skill. A five-factor model of writing originally developed from analyses of 1st and 4th grade English writing samples was applied to Chinese…

  2. Individual Differences, Instructional Theory, and Instructional Design.

    Science.gov (United States)

    1977-06-01

    Technology Group , HumRR O La Jo l l a , CA 92093 300 N. Washington St. Alexan dri a , VA 22314 Mr. A. J. Pesch , Presi dent Eclectech Associates , Inc...iinstru e ’ ton ror differen t individuals . This monitoring may be Jo ~ t ram m i n u t e to m i n u t e , as in Atk inson ’s compu- ter ized s i t u...r ia , VA 22333 Mari ne Corps A i r Force 1 Di recto r, Of fi ce of Man power Researc h Branch Utilization AFMPC /DPMYP HQ, Mari ne Corps (Code MPU

  3. Extraversion predicts individual differences in face recognition.

    Science.gov (United States)

    Li, Jingguang; Tian, Moqian; Fang, Huizhen; Xu, Miao; Li, He; Liu, Jia

    2010-07-01

    In daily life, one of the most common social tasks we perform is to recognize faces. However, the relation between face recognition ability and social activities is largely unknown. Here we ask whether individuals with better social skills are also better at recognizing faces. We found that extraverts who have better social skills correctly recognized more faces than introverts. However, this advantage was absent when extraverts were asked to recognize non-social stimuli (e.g., flowers). In particular, the underlying facet that makes extraverts better face recognizers is the gregariousness facet that measures the degree of inter-personal interaction. In addition, the link between extraversion and face recognition ability was independent of general cognitive abilities. These findings provide the first evidence that links face recognition ability to our daily activity in social communication, supporting the hypothesis that extraverts are better at decoding social information than introverts.

  4. Exploring Individual Differences in Workload Assessment

    Science.gov (United States)

    2014-12-26

    workload theories. Workload Theories The unitary-resource model proposed by Kahneman (1973), suggests a limited amount of attention can be applied to...assessment techniques: Vanilla or resting baseline." Psychophysiology 29, no. 6 (1992): 742-750. Kahneman , Daniel, and Amos Tversky. "On the Psychology

  5. Individual Differences in Time-Sharing Performance

    Science.gov (United States)

    1977-01-01

    relative to solitary task performance levels (e.g., North and Gopher, 1975; Parker, 1964; Sterky and Eysenck , 1965). In attempting such an analysis...Sterky, K. and Eysenck , H. J. Pursuit rotor performance as a function of different degrees of distraction. Life Sciences, 1965) 4, 889-897. Trankell, A

  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......: 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...... to the birth process had no direct connection to thermoregulatory success but were additive in the explanation of piglet behavior. The individual piglet’s rectal temperature at 2 h depends largely on piglet birth weight and on piglet position in relation to sow and littermates. Birth weight is the most...

  7. The Role of Individual Differences in L2 Writing

    Science.gov (United States)

    Kormos, Judit

    2012-01-01

    Although the role of individual differences in second language (L2) speech has been extensively studied, the impact of individual differences on the process of second language writing and the written product has been a neglected area of research. In this paper, I review the most important individual difference factors that might explain variations…

  8. 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.

  9. Hierarchical mixture models for assessing fingerprint individuality

    OpenAIRE

    Dass, Sarat C.; Li, Mingfei

    2009-01-01

    The study of fingerprint individuality aims to determine to what extent a fingerprint uniquely identifies an individual. Recent court cases have highlighted the need for measures of fingerprint individuality when a person is identified based on fingerprint evidence. The main challenge in studies of fingerprint individuality is to adequately capture the variability of fingerprint features in a population. In this paper hierarchical mixture models are introduced to infer the extent of individua...

  10. 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.

  11. Factors affecting variation of different measures of cheese yield and milk nutrient recovery from an individual model cheese-manufacturing process.

    Science.gov (United States)

    Cipolat-Gotet, C; Cecchinato, A; De Marchi, M; Bittante, G

    2013-01-01

    Cheese yield (CY) is the most important technological trait of milk, because cheese-making uses a very high proportion of the milk produced worldwide. Few studies have been carried out at the level of individual milk-producing animals due to a scarcity of appropriate procedures for model-cheese production, the complexity of cheese-making, and the frequent use of the fat and protein (or casein) contents of milk as a proxy for cheese yield. Here, we report a high-throughput cheese manufacturing process that mimics all phases of cheese-making, uses 1.5-L samples of milk from individual animals, and allows the simultaneous processing of 15 samples per run. Milk samples were heated (35°C for 40 min), inoculated with starter culture (90 min), mixed with rennet (51.2 international milk-clotting units/L of milk), and recorded for gelation time. Curds were cut twice (10 and 15 min after gelation), separated from the whey, drained (for 30 min), pressed (3 times, 20 min each, with the wheel turned each time), salted in brine (for 60 min), weighed, and sampled. Whey was collected, weighed, and sampled. Milk, curd, and whey samples were analyzed for pH, total solids, fat content, and protein content, and energy content was estimated. Three measures of percentage cheese yield (%CY) were calculated: %CY(CURD), %CY(SOLIDS), and %CY(WATER), representing the ratios between the weight of fresh curd, the total solids of the curd, and the water content of the curd, respectively, and the weight of the milk processed. In addition, 3 measures of daily cheese yield (dCY, kg/d) were defined, considering the daily milk yield. Three measures of nutrient recovery (REC) were computed: REC(FAT), REC(PROTEIN), and REC(SOLIDS), which represented the ratio between the weights of the fat, protein, and total solids in the curd, respectively, and the corresponding components in the milk. Energy recovery, REC(ENERGY), represented the energy content of the cheese compared with that in the milk. This

  12. Individual Differences: Changing Conceptions in Research and Practice.

    Science.gov (United States)

    Shuell, Thomas J.

    1986-01-01

    Discusses changes in conceptions underlying research on individual differences since the 1940s, trends such as the cognitive revolution in psychology and education, and the increase of societal egalitarianism. Argues that current emphasis on the malleability of individual differences demonstrates a need for individualized instruction that…

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

    NARCIS (Netherlands)

    Zacher, Hannes

    2014-01-01

    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

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

    NARCIS (Netherlands)

    Zacher, Hannes

    2014-01-01

    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

  15. Effects of driver behavior style differences and individual differences on driver sleepiness detection

    Directory of Open Access Journals (Sweden)

    Keyong Li

    2015-04-01

    Full Text Available Driving sleepiness is still a major causes of traffic accidents. Individual drivers, under various conditions, act and respond in different manners. This article presents the attempt of a straight-line driving simulator study that examined the effects of driver behavior style differences and individual differences on driver sleepiness detection which is based on driving performance measures. A total of 15 drivers who were classified into two categories through subjective assessment based on a Driver Behavior Questionnaire participated in driving simulator experiments. A total of 18 detection models, including 15 SE models for each subject, an A model for the aggressive drivers, an NA model for the non-aggressive drivers, and a G model for all experiment participants, were developed using support vector machine method based on driving performance characteristic parameters. The results show that the G model is not suitable for all drivers due to its lower mean accuracy of 69.88% (standard deviation = 7.70% and higher standard deviation. The SE models for each subject show the best detection accuracy performance of 84.26% (standard deviation = 5.38%; however, it is impossible to set up a special detection model for every individual driver. The SD models on different style categories show an accuracy value of 77.54% (standard deviation = 5.78%. The results demonstrate that driver style differences as well as individual differences have great effects on driver sleepiness detection (F = 19.148, p < 0.000.

  16. Explaining individual differences in cognitive processes underlying hindsight bias.

    Science.gov (United States)

    Coolin, Alisha; Erdfelder, Edgar; Bernstein, Daniel M; Thornton, Allen E; Thornton, Wendy Loken

    2015-04-01

    After learning an event's outcome, people's recollection of their former prediction of that event typically shifts toward the actual outcome. Erdfelder and Buchner (Journal of Experimental Psychology: Learning, Memory, and Cognition, 24, 387-414, 1998) developed a multinomial processing tree (MPT) model to identify the underlying processes contributing to this hindsight bias (HB) phenomenon. More recent applications of this model have revealed that, in comparison to younger adults, older adults are more susceptible to two underlying HB processes: recollection bias and reconstruction bias. However, the impact of cognitive functioning on these processes remains unclear. In this article, we extend the MPT model for HB by incorporating individual variation in cognitive functioning into the estimation of the model's core parameters in older and younger adults. In older adults, our findings revealed that (1) better episodic memory was associated with higher recollection ability in the absence of outcome knowledge, (2) better episodic memory and inhibitory control and higher working memory capacity were associated with higher recollection ability in the presence of outcome knowledge, and (3) better inhibitory control was associated with less reconstruction bias. Although the pattern of effects was similar in younger adults, the cognitive covariates did not significantly predict the underlying HB processes in this age group. In sum, we present a novel approach to modeling individual variability in MPT models. We applied this approach to the HB paradigm to identify the cognitive mechanisms contributing to the underlying HB processes. Our results show that working memory capacity and inhibitory control, respectively, drive individual differences in recollection bias and reconstruction bias, particularly in older adults.

  17. A Study of the Impact of Individual Differences on Online Shopping

    OpenAIRE

    Jianfeng Wang; Linwu Gu; Milam Aiken

    2010-01-01

    Previous studies explored the effects of individual cognitive and affective reactions on online shopping and those of individual differences on usage of information systems. However, few studies evaluated how individual differences affect online shopping. This paper draws on the theory of reasoned action (TRA) and the technology acceptance model (TAM) as it attempts to gain understanding of individual difference impacts on online shopping attitudes. The model was tested using data collected f...

  18. A Study of the Impact of Individual Differences on Online Shopping

    OpenAIRE

    Jianfeng Wang; Linwu Gu; Milam Aiken

    2010-01-01

    Previous studies explored the effects of individual cognitive and affective reactions on online shopping and those of individual differences on usage of information systems. However, few studies evaluated how individual differences affect online shopping. This paper draws on the theory of reasoned action (TRA) and the technology acceptance model (TAM) as it attempts to gain understanding of individual difference impacts on online shopping attitudes. The model was tested using data collected f...

  19. Investigating individual differences among targets of workplace incivility.

    Science.gov (United States)

    Milam, Alex C; Spitzmueller, Christiane; Penney, Lisa M

    2009-01-01

    The present study focused on individual differences in Big Five traits among targets of workplace incivility. The authors hypothesized a negative relation between agreeableness and incivility, a positive relation between neuroticism and incivility, and a negative relation between extraversion and incivility. The authors also hypothesized that provocative target behavior is the mediating force that drives these relations. Multisource data from a diverse sample of employees and their coworkers indicate that individuals low in agreeableness and those high in neuroticism experience more incivility than their counterparts. The mediation model was supported for agreeableness and neuroticism. Findings suggest that target traits are important components in incivility research, and should be considered in future research as well as in efforts to alleviate the consequences of incivility.

  20. Individual differences in emotionality: social temperament and health.

    Science.gov (United States)

    Capitanio, John P

    2011-06-01

    Individual differences, the importance of which was identified by Darwin more than 150 years ago, are evident in multiple domains. This review discusses the role of temperament in health-related outcomes in rhesus monkeys. Temperament is proposed as affecting health outcomes via behavioral means, and also via physical means either through its direct association with variation in physiological systems (a "main effects" model), or through its impact on functioning when organisms are in stressful circumstances (an "interaction effects" model). The specific temperament factor described is Sociability, which reflects a tendency to affiliate, and which is associated with positive affect, and with differences in sensitivity of brain dopamine systems. Data are reviewed showing that individual differences in Sociability in rhesus monkeys are related to variation in sympathetic innervation of lymphoid tissue (a main effect), as well as to patterns of coping in socially stressful circumstances (an interaction effect). Results such as these have implications for studies in behavioral ecology, medicine, and even for management practices in captive colonies of nonhuman primates. © 2010 Wiley-Liss, Inc.

  1. Model-based estimation of individual fitness

    Science.gov (United States)

    Link, W.A.; Cooch, E.G.; Cam, E.

    2002-01-01

    Fitness is the currency of natural selection, a measure of the propagation rate of genotypes into future generations. Its various definitions have the common feature that they are functions of survival and fertility rates. At the individual level, the operative level for natural selection, these rates must be understood as latent features, genetically determined propensities existing at birth. This conception of rates requires that individual fitness be defined and estimated by consideration of the individual in a modelled relation to a group of similar individuals; the only alternative is to consider a sample of size one, unless a clone of identical individuals is available. We present hierarchical models describing individual heterogeneity in survival and fertility rates and allowing for associations between these rates at the individual level. We apply these models to an analysis of life histories of Kittiwakes (Rissa tridactyla ) observed at several colonies on the Brittany coast of France. We compare Bayesian estimation of the population distribution of individual fitness with estimation based on treating individual life histories in isolation, as samples of size one (e.g. McGraw & Caswell, 1996).

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

    National Research Council Canada - National Science Library

    Gillen, Christopher T. A; Bergstrøm, Henriette; Forth, Adelle E

    2016-01-01

    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...

  3. Individualized Cognitive Modeling for Close-Loop Task Mitigation

    Science.gov (United States)

    Zhang, Guangfan; Xu, Roger; Wang, Wei; Li, Jiang; Schnell, Tom; Keller, Mike

    2010-01-01

    An accurate real-time operator functional state assessment makes it possible to perform task management, minimize risks, and improve mission performance. In this paper, we discuss the development of an individualized operator functional state assessment model that identifies states likely leading to operational errors. To address large individual variations, we use two different approaches to build a model for each individual using its data as well as data from subjects with similar responses. If a subject's response is similar to that of the individual of interest in a specific functional state, all the training data from this subject will be used to build the individual model. The individualization methods have been successfully verified and validated with a driving test data set provided by University of Iowa. With the individualized models, the mean squared error can be significantly decreased (by around 20%).

  4. 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.

  5. EFL Reading Comprehension, Individual Differences and Text Difficulty

    Science.gov (United States)

    Bilikozen, Neslihan; Akyel, Ayse

    2014-01-01

    This study explores the relative contribution to EFL reading comprehension of the following individual-difference variables: prior knowledge, topic interest, linguistic proficiency, gender, reading motivation, and metacognitive awareness. It also investigates the relationship between the aforementioned individual differences and the role of text…

  6. 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…

  7. EFL Reading Comprehension, Individual Differences and Text Difficulty

    Science.gov (United States)

    Bilikozen, Neslihan; Akyel, Ayse

    2014-01-01

    This study explores the relative contribution to EFL reading comprehension of the following individual-difference variables: prior knowledge, topic interest, linguistic proficiency, gender, reading motivation, and metacognitive awareness. It also investigates the relationship between the aforementioned individual differences and the role of text…

  8. 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…

  9. 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…

  10. Individual Differences in Fear Extinction and Anxiety-Like Behavior

    Science.gov (United States)

    King, Gabrielle; Scott, Elliot; Graham, Bronwyn M.; Richardson, Rick

    2017-01-01

    There is growing appreciation for the substantial individual differences in the acquisition and inhibition of aversive associations, and the insights this might give into identifying individuals particularly vulnerable to stress and psychopathology. We examined whether animals that differed in rate of extinction (i.e., Fast versus Slow) were…

  11. Heterogeneous individuals' behavioral biases model and numerical simulation

    Institute of Scientific and Technical Information of China (English)

    ZHANG Da-yong; LIANG Guo-wei

    2010-01-01

    A model of the relationships between individual cognitive biases and individual decision-making based on the analysis of cognitive biases of bonded rationality individual,has been established in this paper by introducing a set of new variables callod overconfidence coefficient and attribution bias coefficient to the sentiment model.The irrational expectation and irrational risk aversion as two inseparable aspects of bonded rationality are expressed in an unified model,and a method of measuring individual cognitive biases is proposed,which overcomes the shortcomings of traditional normative models that can not describe the differences of behaviors among heterogeneous individuals.As a result,numerical simulations show that individual cognitive risk is a positive interaction with overconfidence coefficient,and a negative interaction with attribution bias coefficient.

  12. 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.

  13. Intrinsic functional connectivity predicts individual differences in distractibility.

    Science.gov (United States)

    Poole, Victoria N; Robinson, Meghan E; Singleton, Omar; DeGutis, Joseph; Milberg, William P; McGlinchey, Regina E; Salat, David H; Esterman, Michael

    2016-06-01

    Distractor suppression, the ability to filter and ignore task-irrelevant information, is critical for efficient task performance. While successful distractor suppression relies on a balance of activity in neural networks responsible for attention maintenance (dorsal attention network; DAN), reorientation (ventral attention network; VAN), and internal thought (default mode network, DMN), the degree to which intrinsic connectivity within and between these networks contributes to individual differences in distractor suppression ability is not well-characterized. For the purposes of understanding these interactions, the current study collected resting-state fMRI data from 32 Veterans and, several months later (7±5 months apart), performance on the additional singleton paradigm, a measure of distractor suppression. Using multivariate support vector regression models composed of resting state connectivity between regions of the DAN, VAN, and DMN, and a leave-one-subject-out cross-validation procedure, we were able to predict an individual's task performance, yielding a significant correlation between the actual and predicted distractor suppression (r=0.48, p=0.0053). Network-level analyses revealed that greater within-network DMN connectivity was predictive of better distractor suppression, while greater connectivity between the DMN and attention networks was predictive of poorer distractor suppression. The strongest connection hubs were determined to be the right frontal eye field and temporoparietal junction of the DAN and VAN, respectively, and medial (ventromedial prefrontal and posterior cingulate cortices) and bilateral prefrontal regions of the DMN. These results are amongst a small but growing number of studies demonstrating that resting state connectivity is related to stable individual differences in cognitive ability, and suggest that greater integrity and independence of the DMN is related to better attentional ability.

  14. Individual eye model based on wavefront aberration

    Science.gov (United States)

    Guo, Huanqing; Wang, Zhaoqi; Zhao, Qiuling; Quan, Wei; Wang, Yan

    2005-03-01

    Based on the widely used Gullstrand-Le Grand eye model, the individual human eye model has been established here, which has individual corneal data, anterior chamber depth and the eyeball depth. Furthermore, the foremost thing is that the wavefront aberration calculated from the individual eye model is equal to the eye's wavefront aberration measured with the Hartmann-shack wavefront sensor. There are four main steps to build the model. Firstly, the corneal topography instrument was used to measure the corneal surfaces and depth. And in order to input cornea into the optical model, high-order aspheric surface-Zernike Fringe Sag surface was chosen to fit the corneal surfaces. Secondly, the Hartmann-shack wavefront sensor, which can offer the Zernike polynomials to describe the wavefront aberration, was built to measure the wavefront aberration of the eye. Thirdly, the eye's axial lengths among every part were measured with A-ultrasonic technology. Then the data were input into the optical design software-ZEMAX and the crystalline lens's shapes were optimized with the aberration as the merit function. The individual eye model, which has the same wavefront aberrations with the real eye, is established.

  15. Individual differences in chemotherapy-induced anticipatory nausea

    Directory of Open Access Journals (Sweden)

    Marcial eRodríguez

    2013-08-01

    Full Text Available Anticipatory Nausea (AN is a severe side effect of chemotherapy that can lead cancer patients to discontinue their treatment. This kind of nausea is usually elicited by the re-exposure of the patients to the clinical context they need to attend to be treated. There has been considerable agreement that AN represents a paradigmatic example of Pavlovian conditioning, and within this framework, several behavioral interventions have been proposed in order to prevent this psychopathology. However, some studies have questioned the validity of the Pavlovian approach, suggesting that CS-US associations are neither necessary nor sufficient for AN to occur. The data and the alternative theories behind such criticisms are discussed. Additionally, it is suggested that animal models of AN could be enriched by taking into account rats’ individual differences.

  16. Individual differences in holistic processing predict face recognition ability.

    Science.gov (United States)

    Wang, Ruosi; Li, Jingguang; Fang, Huizhen; Tian, Moqian; Liu, Jia

    2012-02-01

    Why do some people recognize faces easily and others frequently make mistakes in recognizing faces? Classic behavioral work has shown that faces are processed in a distinctive holistic manner that is unlike the processing of objects. In the study reported here, we investigated whether individual differences in holistic face processing have a significant influence on face recognition. We found that the magnitude of face-specific recognition accuracy correlated with the extent to which participants processed faces holistically, as indexed by the composite-face effect and the whole-part effect. This association is due to face-specific processing in particular, not to a more general aspect of cognitive processing, such as general intelligence or global attention. This finding provides constraints on computational models of face recognition and may elucidate mechanisms underlying cognitive disorders, such as prosopagnosia and autism, that are associated with deficits in face recognition.

  17. 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

  18. Assessing Students' Learning Styles and Teaching for Individual Differences

    Science.gov (United States)

    Papalia, Anthony

    1978-01-01

    Since it is assumed that students' classroom behaviors reflect learning modalities and attitudes, this investigation was undertaken to assist teachers in identifying their students' individual differences. (Author/NCR)

  19. 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.

  20. Are individual differences in arithmetic fact retrieval related to inhibition?

    OpenAIRE

    Bellon, Elien

    2016-01-01

    Although it has been proposed that inhibition is related to individual differences in mathematical achievement, it is not clear how it is related to specific aspects of mathematical skills, such as arithmetic fact retrieval. The present study therefore investigated the association between inhibition and arithmetic fact retrieval and further examined the unique role of inhibition in individual differences in arithmetic fact retrieval, in addition to numerical magnitude processin...

  1. Individual differences in the acquisition of second language phonology

    OpenAIRE

    GOLESTANI, NARLY; Zatorre, Robert J.

    2009-01-01

    Perceptual training was employed to characterize individual differences in non-native speech sound learning. Fifty-nine adult English speakers were trained to distinguish the Hindi dental–retroflex contrast, as well as a tonal pitch contrast. Training resulted in overall group improvement in the ability to identify and to discriminate the phonetic and the tonal contrasts, but there were considerable individual differences in performance. A category boundary effect during the post-training dis...

  2. Causes of Individual Differences in Animal Exploration and Search

    NARCIS (Netherlands)

    Reader, Simon M.|info:eu-repo/dai/nl/30483162X

    2015-01-01

    Numerous studies have documented individual differences in exploratory tendencies and other phenomena related to search, and these differences have been linked to fitness. Here, I discuss the origins of these differences, focusing on how experience shapes animal search and exploration. The origin of

  3. Causes of Individual Differences in Animal Exploration and Search

    NARCIS (Netherlands)

    Reader, Simon M.

    2015-01-01

    Numerous studies have documented individual differences in exploratory tendencies and other phenomena related to search, and these differences have been linked to fitness. Here, I discuss the origins of these differences, focusing on how experience shapes animal search and exploration. The origin of

  4. 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.

  5. 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

  6. Modelling larval movement data from individual bioassays.

    Science.gov (United States)

    McLellan, Chris R; Worton, Bruce J; Deasy, William; Birch, A Nicholas E

    2015-05-01

    We consider modelling the movements of larvae using individual bioassays in which data are collected at a high-frequency rate of five observations per second. The aim is to characterize the behaviour of the larvae when exposed to attractant and repellent compounds. Mixtures of diffusion processes, as well as Hidden Markov models, are proposed as models of larval movement. These models account for directed and localized movements, and successfully distinguish between the behaviour of larvae exposed to attractant and repellent compounds. A simulation study illustrates the advantage of using a Hidden Markov model rather than a simpler mixture model. Practical aspects of model estimation and inference are considered on extensive data collected in a study of novel approaches for the management of cabbage root fly.

  7. 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.

  8. Individual odor differences and their social functions in insects.

    Science.gov (United States)

    Barrows, E M; Bell, W J; Michener, C D

    1975-01-01

    The evolution of individual or subgroup differences in odors of halictine bees is suggested from possible widespread intraspecific variation in pheromones. An important result of such variation may be maintenance of genetic polymorphisms; in nesting Hymenoptera odor differences may also facilitate individual nest recognition. In Lasioglosum zephyrum males habituate to odors of different females and perhaps thus save time by not trying to copulate with nonreceptive individuals. Guards (females) at nest entrances distinguish their few nestmates (other females) from other conspecific individuals by odors, seemingly pheromones. Duration of the habituation in L. zephyrum is at least an hour (perhaps much more) for males in relation to females and 6 or 7 days for guards in relation to nestmates. Studies of pheromones should take into consideration the possibility of pheromonal polymorphism in any species and the likelihood that it may be significant from biological and practical viewpoints. PMID:1058498

  9. Individual differences and metacognitive knowledge of visual search strategy.

    Science.gov (United States)

    Proulx, Michael J

    2011-01-01

    A crucial ability for an organism is to orient toward important objects and to ignore temporarily irrelevant objects. Attention provides the perceptual selectivity necessary to filter an overwhelming input of sensory information to allow for efficient object detection. Although much research has examined visual search and the 'template' of attentional set that allows for target detection, the behavior of individual subjects often reveals the limits of experimental control of attention. Few studies have examined important aspects such as individual differences and metacognitive strategies. The present study analyzes the data from two visual search experiments for a conjunctively defined target (Proulx, 2007). The data revealed attentional capture blindness, individual differences in search strategies, and a significant rate of metacognitive errors for the assessment of the strategies employed. These results highlight a challenge for visual attention studies to account for individual differences in search behavior and distractibility, and participants that do not (or are unable to) follow instructions.

  10. Individual differences and metacognitive knowledge of visual search strategy.

    Directory of Open Access Journals (Sweden)

    Michael J Proulx

    Full Text Available A crucial ability for an organism is to orient toward important objects and to ignore temporarily irrelevant objects. Attention provides the perceptual selectivity necessary to filter an overwhelming input of sensory information to allow for efficient object detection. Although much research has examined visual search and the 'template' of attentional set that allows for target detection, the behavior of individual subjects often reveals the limits of experimental control of attention. Few studies have examined important aspects such as individual differences and metacognitive strategies. The present study analyzes the data from two visual search experiments for a conjunctively defined target (Proulx, 2007. The data revealed attentional capture blindness, individual differences in search strategies, and a significant rate of metacognitive errors for the assessment of the strategies employed. These results highlight a challenge for visual attention studies to account for individual differences in search behavior and distractibility, and participants that do not (or are unable to follow instructions.

  11. Personality differences between tattooed and non-tattooed individuals.

    Science.gov (United States)

    Swami, Viren; Pietschnig, Jakob; Bertl, Bianca; Nader, Ingo W; Stieger, Stefan; Voracek, Martin

    2012-08-01

    This study examined differences between tattooed and non-tattooed individuals on a range of personality and individual difference measures. A community sample of 540 individuals from the southern German-speaking area of central Europe completed a survey consisting of measures of the Big Five personality factors, Need for Uniqueness, Self-esteem, sensation seeking, Religious and Spiritual Beliefs, Attitudes Toward Tattoos, tattoo possession, and demographics. Preliminary analyses showed that 22% of the total sample possessed at least one tattoo. Further analyses showed that, compared with non-tattooed (n = 420) individuals, tattooed participants (n = 120) had significantly higher scores on Extraversion, Experience Seeking, Need for Uniqueness, and held more positive Attitudes Toward Tattoos, although effect sizes of these group differences were generally small- to medium-sized. These results are considered in relation to the contemporary prevalence of tattoos in socioeconomically developed societies.

  12. Are Some Negotiators Better Than Others? Individual Differences in Bargaining Outcomes

    OpenAIRE

    Elfenbein, Hillary Anger; Curhan, Jared R.; Eisenkraft, Noah; Shirako, Aiwa; Baccaro, Lucio

    2008-01-01

    The authors address the long-standing mystery of stable individual differences in negotiation performance, on which intuition and conventional wisdom have clashed with inconsistent empirical findings. The present study used the Social Relations Model to examine individual differences directly via consistency in performance across multiple negotiations and to disentangle the roles of both parties within these inherently dyadic interactions. Individual differences explained a substantial 46% of...

  13. Variations in Cognitive Maps: Understanding Individual Differences in Navigation

    Science.gov (United States)

    Weisberg, Steven M.; Schinazi, Victor R.; Newcombe, Nora S.; Shipley, Thomas F.; Epstein, Russell A.

    2014-01-01

    There are marked individual differences in the formation of cognitive maps both in the real world and in virtual environments (VE; e.g., Blajenkova, Motes, & Kozhevnikov, 2005; Chai & Jacobs, 2010; Ishikawa & Montello, 2006; Wen, Ishikawa, & Sato, 2011). These differences, however, are poorly understood and can be difficult to…

  14. Individual Differences in Phonological Development: Ages One and Three Years.

    Science.gov (United States)

    Vihman, Marilyn May; Greenlee, Mel

    1987-01-01

    The persistence of individual differences in phonological development of 10 normally developing children observed at age one and again at age three was studied. The children differed considerably in rate of vocabulary acquisition and relative phonological maturity and also in their general approach to learning. (Author/JDD)

  15. 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…

  16. 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].

  17. 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].

  18. 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.

  19. Individual differences in working memory capacity and temporal discrimination.

    Directory of Open Access Journals (Sweden)

    James M Broadway

    Full Text Available Temporal judgment in the milliseconds-to-seconds range depends on consistent attention to time and robust working memory representation. Individual differences in working memory capacity (WMC predict a wide range of higher-order and lower-order cognitive abilities. In the present work we examined whether WMC would predict temporal discrimination. High-WMC individuals were more sensitive than low-WMC at discriminating the longer of two temporal intervals across a range of temporal differences. WMC-related individual differences in temporal discrimination were not eliminated by including a measure of fluid intelligence as a covariate. Results are discussed in terms of attention, working memory and other psychological constructs.

  20. Individual differences in children's and parents' generic language.

    Science.gov (United States)

    Gelman, Susan A; Ware, Elizabeth A; Kleinberg, Felicia; Manczak, Erika M; Stilwell, Sarah M

    2014-01-01

    Generics ("Dogs bark") convey important information about categories and facilitate children's learning. Two studies with parents and their 2- or 4-year-old children (N = 104 dyads) examined whether individual differences in generic language use are as follows: (a) stable over time, contexts, and domains, and (b) linked to conceptual factors. For both children and parents, individual differences in rate of generic production were stable across time, contexts, and domains, and parents' generic usage significantly correlated with that of their own children. Furthermore, parents' essentialist beliefs correlated with their own and their children's rates of generic frequency. These results indicate that generic language use exhibits substantial stability and may reflect individual differences in speakers' conceptual attitudes toward categories. © 2013 The Authors. Child Development © 2013 Society for Research in Child Development, Inc.

  1. The Impact of Adapting Content for Students with Individual Differences

    Science.gov (United States)

    Flores, Raymond; Ari, Fatih; Inan, Fethi A.; Arslan-Ari, Ismahan

    2012-01-01

    Combining adaptive hypermedia methods with strategies proposed by instructional theory and motivation models, an adaptable tutorial was designed and developed. The aim of this study was to assess whether the goals of an adaptable tutorial, which individualized instruction based on student motivation and prior knowledge, were being met (i.e.…

  2. Origins of Individual Differences in Theory of Mind: From Nature to Nurture?

    Science.gov (United States)

    Hughes, Claire; Jaffee, Sara R.; Happ, Francesca; Taylor, Alan; Caspi, Avshalom; Moffitt, Terrie E.

    2005-01-01

    In this study of the origins of individual differences in theory of mind (ToM), the Environmental Risk (E-Risk) Longitudinal Twin Study sample of 1,116 sixty-month-old twin pairs completed a comprehensive battery of ToM tasks. Individual differences in ToM were striking and strongly associated with verbal ability. Behavioral genetic models of the…

  3. Individual Differences in the Flexibility of Peripersonal Space.

    Science.gov (United States)

    Hunley, Samuel B; Marker, Arwen M; Lourenco, Stella F

    2017-01-01

    The current study investigated individual differences in the flexibility of peripersonal space (i.e., representational space near the body), specifically in relation to trait claustrophobic fear (i.e., fear of suffocating or being physically restricted). Participants completed a line bisection task with either a laser pointer (Laser condition), allowing for a baseline measure of the size of one's peripersonal space, or a stick (Stick condition), which produces expansion of one's peripersonal space. Our results revealed that individuals high in claustrophobic fear had larger peripersonal spaces than those lower in claustrophobic fear, replicating previous research. We also found that, whereas individuals low in claustrophobic fear demonstrated the expected expansion of peripersonal space in the Stick condition, individuals high in claustrophobic fear showed less expansion, suggesting decreased flexibility. We discuss these findings in relation to the defensive function of peripersonal space and reduced attentional flexibility associated with trait anxieties.

  4. 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.

  5. 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.

  6. 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.

  7. Individual differences in anxiety and executive functioning: a multidimensional view.

    Science.gov (United States)

    Visu-Petra, Laura; Miclea, Mircea; Visu-Petra, George

    2013-01-01

    The relationship between individual differences in anxiety and executive functioning was investigated in a sample of young adults. Verbal and spatial working memory, resistance to interference, negative priming, and task-switching measures were used to assess three executive functioning dimensions: updating, inhibition, and shifting. An additional index of basic psychomotor speed was added to this cognitive battery. According to the multidimensional interaction model of anxiety proposed by Endler (1997), state (cognitive-worry and autonomic-emotional) and trait (related to social evaluation, physical danger, ambiguous situations, and daily routines) anxiety were assessed in this evaluation context. Results indicated that shifting and inhibition (negative priming) efficiency were negatively related to state (cognitive-worry) and trait (related to social evaluation) anxiety. However, there was a relative advantage of subjects higher in social evaluation apprehensions in their memory updating performance. The results are consistent with several predictions of the attentional control theory (Eysenck, Derakshan, Santos, & Calvo, 2007), and are relevant for research regarding the interaction of situational, personality, and cognitive functioning dimensions.

  8. 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.

  9. Individual Differences in RIASEC Profile Similarity across Five Interest Inventories

    Science.gov (United States)

    Savickas, Mark L.; Taber, Brian J.

    2006-01-01

    The present research indicated substantial variation within the 5 RIASEC (Realistic, Investigative, Artistic, Social, Enterprising, Conventional) profiles obtained by each of 99 individuals who responded to the same 5 interest inventories. The authors concluded that the RIASEC indicators on each inventory probably reflect different portions of the…

  10. Career Landmarks in Science: Individual Differences and Interdisciplinary Contrasts.

    Science.gov (United States)

    Simonton, Dean Keith

    1991-01-01

    Examined the location of the first, best, and last contributions of creative careers. Hypotheses specified the ways in which these landmarks should vary according to individual differences and interdisciplinary contrasts. Hypotheses were confirmed for scientists and inventors. Results lead to further theoretical constraints, new predictions, and…

  11. Individual Differences in Sibling Teaching in Early and Middle Childhood

    Science.gov (United States)

    Howe, Nina; Recchia, Holly

    2009-01-01

    Research Findings: Sibling teaching and learning behaviors were investigated in 2 studies of children in early and middle childhood. Study 1 addressed individual differences in teaching/learning and associations with dyadic age, age gap, gender, birth order, and relationship quality in 71 middle-class dyads (firstborns M age = 81.54 months;…

  12. Exploring Individual Differences in Attitudes toward Audience Response Systems

    Science.gov (United States)

    Kay, Robin H.; Knaack, Liesel

    2009-01-01

    The purpose of this study was to examine individual differences in attitudes toward Audience Response Systems (ARSs) in secondary school classrooms. Specifically, the impact of gender, grade, subject area, computer comfort level, participation level, and type of use were examined in 659 students. Males had significantly more positive attitudes…

  13. Individual Differences in the Acquisition of Second Language Phonology

    Science.gov (United States)

    Golestani, Narly; Zatorre, Robert J.

    2009-01-01

    Perceptual training was employed to characterize individual differences in non-native speech sound learning. Fifty-nine adult English speakers were trained to distinguish the Hindi dental-retroflex contrast, as well as a tonal pitch contrast. Training resulted in overall group improvement in the ability to identify and to discriminate the phonetic…

  14. Some Aspects of Individual Differences in Mathematics Instruction.

    Science.gov (United States)

    Radatz, Hendrik

    1979-01-01

    The article includes a general discussion of individual differences and a report of a study conducted as a part of the Frankfurt Project. The study indicated that, in primary school, reflective pupils seem to be better achievers in mathematics than impulsive students. (MK)

  15. Cultural Differences between Arabs and Americans: Individualism-Collectivism Revisited.

    Science.gov (United States)

    Buda, Richard; Elsayed-Elkhouly, Sayed M.

    1998-01-01

    Cultural differences between Arabs and Americans were investigated using the individualism-collectivism survey of J. Wagner (1995). Arab subjects (n=331) were significantly more collectivist than U.S. subjects (n=102), and within the Arab group, Egyptian subjects (n=224) were significantly more individualistic than Gulf States subjects.…

  16. Individual Differences in Statistical Learning Predict Children's Comprehension of Syntax

    Science.gov (United States)

    Kidd, Evan; Arciuli, Joanne

    2016-01-01

    Variability in children's language acquisition is likely due to a number of cognitive and social variables. The current study investigated whether individual differences in statistical learning (SL), which has been implicated in language acquisition, independently predicted 6- to 8-year-old's comprehension of syntax. Sixty-eight (N = 68)…

  17. Individual Differences in Memory: Theory, Data, and Educational Implications

    Science.gov (United States)

    Royer, James M.; And Others

    1978-01-01

    Individual differences in memory can be studied from two theoretical perspectives: Reappearance Theory or Constructive Theory. To test the Constructive Theory, two experiments examined the retention of high and low ability students. The results of both experiments supported the hypothesis that learners who acquire information rapidly also display…

  18. 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…

  19. Individual Differences in Syntactic Priming in Language Acquisition

    Science.gov (United States)

    Kidd, Evan

    2012-01-01

    Although the syntactic priming methodology is a promising tool for language acquisition researchers, using the technique with children raises issues that are not problematic in adult research. The current paper reports on an individual differences study that addressed some of these outstanding issues. (a) Does priming purely reflect syntactic…

  20. Different brains process numbers differently: structural bases of individual differences in spatial and nonspatial number representations.

    Science.gov (United States)

    Krause, Florian; Lindemann, Oliver; Toni, Ivan; Bekkering, Harold

    2014-04-01

    A dominant hypothesis on how the brain processes numerical size proposes a spatial representation of numbers as positions on a "mental number line." An alternative hypothesis considers numbers as elements of a generalized representation of sensorimotor-related magnitude, which is not obligatorily spatial. Here we show that individuals' relative use of spatial and nonspatial representations has a cerebral counterpart in the structural organization of the posterior parietal cortex. Interindividual variability in the linkage between numbers and spatial responses (faster left responses to small numbers and right responses to large numbers; spatial-numerical association of response codes effect) correlated with variations in gray matter volume around the right precuneus. Conversely, differences in the disposition to link numbers to force production (faster soft responses to small numbers and hard responses to large numbers) were related to gray matter volume in the left angular gyrus. This finding suggests that numerical cognition relies on multiple mental representations of analogue magnitude using different neural implementations that are linked to individual traits.

  1. A microcosmic discrete occupant evacuation model based on individual characteristics

    Institute of Scientific and Technical Information of China (English)

    YANG Lizhong; LI Jian; ZHAO Daoliang; FANG Weifeng; FAN Weicheng

    2004-01-01

    The research of occupant evacuation in an emergency is of great benefit to building design and evacuation guidance. In this paper a microcosmic discrete evacuation model based on Cellular Automata (CA) is presented, in which the occupants' individual characteristics are considered. Thus, our model has given a description of evacuation route choice with influencing factors, including: individual knowledge of the building,individual realization of the emergency development, and the attractive and repulsive force between occupants. This model differs somewhat from other models in the attention to the associative and separate effect of influencing factors, based on occupant's behaviors. In addition, the model could reveal the phenomenon of escape in fire, as those simulations involving a fire condition have shown.

  2. Consistent differences in individual reactions to drugs and dummies

    Science.gov (United States)

    Joyce, C. R. B.

    1959-01-01

    The tendency of some individuals to report changes of physical and mental state after taking pharmacologically inert substances has been investigated experimentally. In a class of healthy medical students, those individuals who reported symptoms and those who did not made significantly different scores on a number of behavioural tests. The likely reactions of the members of a second class (containing none of the previous participants) to dummies were then predicted from their scores on the same tests, some of which were found to be much more efficient predictors than would have been expected by chance. Some implications for further research and for clinical medicine are discussed. PMID:14408028

  3. Resistance to change: developing an individual differences measure.

    Science.gov (United States)

    Oreg, Shaul

    2003-08-01

    The Resistance to Change Scale was designed to measure an individual's dispositional inclination to resist changes. In Study 1, exploratory analyses indicated 4 reliable factors: Routine Seeking, Emotional Reaction to Imposed Change, Cognitive Rigidity, and Short-Term Focus. Studies 2, 3, and 4 confirmed this structure and demonstrated the scale's convergent and discriminant validities. Studies 5, 6, and 7 demonstrated the concurrent and predictive validities of the scale in 3 distinct contexts. The scale can be used to account for the individual-difference component of resistance to change and to predict reactions to specific change.

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

    Science.gov (United States)

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

    2014-10-01

    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 information, enhancement of relevant information, or both. Here we used steady-state visual evoked potentials (SSVEPs) with the Eriksen flanker task to track simultaneously the attention to relevant and irrelevant information by tagging target and distractors with different frequencies. This design allowed us to dissociate attentional biasing of perceptual processing (via SSVEPs) and stimulus processing in the frontal cognitive control network (via time-frequency analyses of EEG data). We show that while preparing for the upcoming stimulus, high- and low-WMC individuals use different strategies: High-WMC individuals show attentional suppression of the irrelevant stimuli, whereas low-WMC individuals demonstrate attentional enhancement of the relevant stimuli. Moreover, behavioral performance was predicted by trial-to-trial fluctuations in strength of distractor-suppression for high-WMC participants. We found no evidence for WMC-related differences in cognitive control network functioning, as measured by midfrontal theta-band power. Taken together, these findings suggest that early suppression of irrelevant information is a key underlying neural mechanism by which superior attention control abilities are implemented.

  5. ERP and behavioral evidence of individual differences in metaphor comprehension.

    Science.gov (United States)

    Kazmerski, Victoria A; Blasko, Dawn G; Dessalegn, Banchiamlack G

    2003-07-01

    In two experiments, we examined individual differences in metaphor processing. In Experiment 1, the subjects judged the literal truth of literal, metaphorical, and scrambled sentences. Overall, metaphors were more difficult to judge as false, in comparison with scrambled controls, suggesting that the metaphorical meaning was being processed automatically. However, there were individual differences in that high-IQ subjects showed more interference. These effects were reflected in ERP amplitude differences at the onset of N400 and after the response. In Experiment 2, the subjects completed IQ tests and a series of working memory tests and then rated and interpreted the same set of metaphors. The results showed that IQ was correlated with working memory capacity and that low-IQ subjects had similar ratings but poorer quality interpretations than did high-IQ subjects. The results were most consistent with a constraint satisfaction approach to metaphor comprehension.

  6. Personality and individual difference correlates of positive body image.

    Science.gov (United States)

    Swami, Viren; Hadji-Michael, Maria; Furnham, Adrian

    2008-09-01

    In the present study, 101 women and 106 men from a community sample of British adults completed the Body Appreciation Scale (BAS), along with a battery of individual difference measures and demographics. Contrary to previous findings, there were no sex differences in BAS scores, either before or after controlling for individual differences in other measures. The results also showed that, moderating for participants' sex, self-assessed attractiveness, educational qualifications, neuroticism, extraversion, and BMI were all significant predictors of body appreciation. In addition, higher media consumption and higher (male-stereotypic) instrumentality were associated with, but did not predict, higher body appreciation. These results are discussed in relation to the extant work on body image.

  7. How Can Evolutionary Psychology Successfully Explain Personality and Individual Differences?

    Science.gov (United States)

    Buss, David M

    2009-07-01

    Although evolutionary psychology has been successful in explaining some species-typical and sex-differentiated adaptations, a large question that has largely eluded the field is this: How can the field successfully explain personality and individual differences? This article highlights some promising theoretical directions for tackling this question. These include life-history theory, costly signaling theory, environmental variability in fitness optima, frequency-dependent selection, mutation load, and flexibly contingent shifts in strategy according to environmental conditions. Tackling the explanatory question also requires progress on three fronts: (a) reframing some personality traits as forms of strategic individual differences; (b) providing a nonarbitrary, evolutionary-based formulation of environments as distributions and salience profiles of adaptive problems; and (c) identifying which strategies thrive and which falter in these differing problem-defined environments.

  8. Explaining affective linkages in teams: individual differences in susceptibility to contagion and individualism-collectivism.

    Science.gov (United States)

    Ilies, Remus; Wagner, David T; Morgeson, Frederick P

    2007-07-01

    To expand on the understanding of how affective states are linked within teams, the authors describe a longitudinal study examining the linkages between team members' affective states over time. In a naturalistic team performance setting, they found evidence that the average affective state of the other team members was related to an individual team member's affect over time, even after controlling for team performance. In addition, they found that these affective linkages were moderated by individual differences in susceptibility to emotional contagion and collectivistic tendencies such that the strength of the linkage was stronger for those high in susceptibility and those with collectivistic tendencies. Implications for research and practice are discussed.

  9. 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.

  10. Factors contributing to individual differences in facial expression categorisation.

    Science.gov (United States)

    Green, Corinne; Guo, Kun

    2016-12-29

    Individuals vary in perceptual accuracy when categorising facial expressions, yet it is unclear how these individual differences in non-clinical population are related to cognitive processing stages at facial information acquisition and interpretation. We tested 104 healthy adults in a facial expression categorisation task, and correlated their categorisation accuracy with face-viewing gaze allocation and personal traits assessed with Autism Quotient, anxiety inventory and Self-Monitoring Scale. The gaze allocation had limited but emotion-specific impact on categorising expressions. Specifically, longer gaze at the eyes and nose regions were coupled with more accurate categorisation of disgust and sad expressions, respectively. Regarding trait measurements, higher autistic score was coupled with better recognition of sad but worse recognition of anger expressions, and contributed to categorisation bias towards sad expressions; whereas higher anxiety level was associated with greater categorisation accuracy across all expressions and with increased tendency of gazing at the nose region. It seems that both anxiety and autistic-like traits were associated with individual variation in expression categorisation, but this association is not necessarily mediated by variation in gaze allocation at expression-specific local facial regions. The results suggest that both facial information acquisition and interpretation capabilities contribute to individual differences in expression categorisation within non-clinical populations.

  11. What contributes to individual differences in brain structure?

    Directory of Open Access Journals (Sweden)

    Jenny eGu

    2014-04-01

    Full Text Available Individual differences in adult human brain structure have been found to reveal a great deal of information about variability in behaviours, cognitive abilities and mental and physical health. Driven by such evidence, what contributes to individual variation in brain structure has gained accelerated attention as a research question. Findings thus far appear to support the notion that an individual’s brain architecture is determined largely by genetic and environmental influences. This review aims to evaluate the empirical literature on whether and how genes and the environment contribute to individual differences in brain structure. It first considers how genetic and environmental effects may separately contribute to brain morphology, by examining evidence from twin, genome-wide association, cross-sectional and longitudinal studies. Next, evidence for the influence of the complex interplay between genetic and environmental factors, characterised as gene-environment interactions and correlations, is reviewed. In evaluating the extant literature, this review will conclude that both genetic and environmental factors play critical roles in contributing to individual variability in brain structure.

  12. Analysis of individual differences in radiosensitivity using genome editing.

    Science.gov (United States)

    Matsuura, S; Royba, E; Akutsu, S N; Yanagihara, H; Ochiai, H; Kudo, Y; Tashiro, S; Miyamoto, T

    2016-06-01

    Current standards for radiological protection of the public have been uniformly established. However, individual differences in radiosensitivity are suggested to exist in human populations, which could be caused by nucleotide variants of DNA repair genes. In order to verify if such genetic variants are responsible for individual differences in radiosensitivity, they could be introduced into cultured human cells for evaluation. This strategy would make it possible to analyse the effect of candidate nucleotide variants on individual radiosensitivity, independent of the diverse genetic background. However, efficient gene targeting in cultured human cells is difficult due to the low frequency of homologous recombination (HR) repair. The development of artificial nucleases has enabled efficient HR-mediated genome editing to be performed in cultured human cells. A novel genome editing strategy, 'transcription activator-like effector nuclease (TALEN)-mediated two-step single base pair editing', has been developed, and this was used to introduce a nucleotide variant associated with a chromosomal instability syndrome bi-allelically into cultured human cells to demonstrate that it is the causative mutation. It is proposed that this editing technique will be useful to investigate individual radiosensitivity.

  13. Individual differences effects on the psychological refractory period

    OpenAIRE

    Laguë-Beauvais, Maude; Gagnon, Christine; Castonguay, Nathalie; Bherer, Louis

    2013-01-01

    The goal of this study was to assess the impact of individual neuropsychological differences on the ability to share attention between concurrent tasks. Participants (n = 20) were trained on six single task practice sessions and dual-task was assessed with reaction time performance on a psychological refractory period (PRP) paradigm. Neuropsychological test scores were also acquired. Furthermore, one of the known variables that can influence performances on neuropsychological tests is gender,...

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

    OpenAIRE

    Mirela Mihić; Ivana Kursan

    2010-01-01

    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 rese...

  15. Individual differences in false memory from misinformation: Cognitive factors

    OpenAIRE

    Zhu, B.; Loftus, EF; Lin, C.; He, Q.; Chen, C; Li, H; Xue, G.; Lu, Z.; Dong, Q.

    2010-01-01

    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 Advance...

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

    OpenAIRE

    Christopher T. A. Gillen; Henriette Bergstrøm; Adelle E. Forth

    2016-01-01

    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-...

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

    OpenAIRE

    Christopher T. A. Gillen; Henriette Bergstrøm; Forth, Adelle E.

    2016-01-01

    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-...

  18. 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.

  19. Task-free MRI predicts individual differences in brain activity during task performance.

    Science.gov (United States)

    Tavor, I; Parker Jones, O; Mars, R B; Smith, S M; Behrens, T E; Jbabdi, S

    2016-04-01

    When asked to perform the same task, different individuals exhibit markedly different patterns of brain activity. This variability is often attributed to volatile factors, such as task strategy or compliance. We propose that individual differences in brain responses are, to a large degree, inherent to the brain and can be predicted from task-independent measurements collected at rest. Using a large set of task conditions, spanning several behavioral domains, we train a simple model that relates task-independent measurements to task activity and evaluate the model by predicting task activation maps for unseen subjects using magnetic resonance imaging. Our model can accurately predict individual differences in brain activity and highlights a coupling between brain connectivity and function that can be captured at the level of individual subjects.

  20. Psittacine cognition: Individual differences and sources of variation.

    Science.gov (United States)

    Cussen, Victoria A

    2017-01-01

    Both the number and breadth of avian cognition studies have expanded in the past three decades. Parrots have a long history as subjects in avian cognition research. This paper summarizes results from a number of parrot species tested on basic learning, and physical & social cognitive processes, with an emphasis on individual differences. Early psittacine studies were aimed at demonstrating a particular cognitive ability existed in a given species. Because of this proof of capacity focus, early studies typically included only a single individual or a dyad of parrots. Existing reviews of parrot cognition tend to focus on a particular cognitive component in a single species, or even a single individual. Despite the narrow focus, results from increasing sample sizes show intraspecific variation across a variety of cognitive assessments and parrot species. Intraspecific variability in performance on cognitive tasks highlights the need for establishing a cognitive normal range for a given species and process. To accomplish this, large numbers of individuals need to be tested and non-cognitive sources of variability need to be controlled. Once species typical cognitive normal ranges are established, cognitive comparisons can be made between parrot species and between parrots and other taxa.

  1. Variable Global Dysconnectivity and Individual Differences in Schizophrenia

    Science.gov (United States)

    Cole, Michael W.; Anticevic, Alan; Repovs, Grega; Barch, Deanna

    2011-01-01

    Background A fundamental challenge for understanding neuropsychiatric disease is identifying sources of individual differences in psychopathology, especially when there is substantial heterogeneity of symptom expression, such as is found in schizophrenia (SCZ). We hypothesized that such heterogeneity might arise in part from consistently widespread yet variably patterned alterations in the connectivity of focal brain regions. Methods We used resting state functional connectivity magnetic resonance imaging to identify variable global dysconnectivity in 23 patients with DSM-IV SCZ relative to 22 age-, gender-, and parental socioeconomic status-matched control subjects with a novel global brain connectivity method that is robust to high variability across individuals. We examined cognitive functioning with a modified Sternberg task and subtests from the Wechsler Adult Intelligence Scale—Third Edition. We measured symptom severity with the Scale for Assessment of Positive and Negative Symptoms. Results We identified a dorsolateral prefrontal cortex (PFC) region with global and highly variable dysconnectivity involving within-PFC underconnectivity and non-PFC overconnectivity in patients. Variability in this “under/over” pattern of dysconnectivity strongly predicted the severity of cognitive deficits (matrix reasoning IQ, verbal IQ, and working memory performance) as well as individual differences in every cardinal symptom domain of SCZ (poverty, reality distortion, and disorganization). Conclusions These results suggest that global dysconnectivity underlies dorsolateral PFC involvement in the neuropathology of SCZ. Furthermore, these results demonstrate the possibility that specific patterns of dysconnectivity with a given network hub region might explain individual differences in symptom presentation in SCZ. Critically, such findings might extend to other neuropathologies with diverse presentation. PMID:21496789

  2. Individual differences in dopamine level modulate the ego depletion effect.

    Science.gov (United States)

    Dang, Junhua; Xiao, Shanshan; Liu, Ying; Jiang, Yumeng; Mao, Lihua

    2016-01-01

    Initial exertion of self-control impairs subsequent self-regulatory performance, which is referred to as the ego depletion effect. The current study examined how individual differences in dopamine level, as indexed by eye blink rate (EBR), would moderate ego depletion. An inverted-U-shaped relationship between EBR and subsequent self-regulatory performance was found when participants initially engaged in self-control but such relationship was absent in the control condition where there was no initial exertion, suggesting individuals with a medium dopamine level may be protected from the typical ego depletion effect. These findings are consistent with a cognitive explanation which considers ego depletion as a phenomenon similar to "switch costs" that would be neutralized by factors promoting flexible switching.

  3. Examination of recreational motives of individuals: Demographic differences

    Directory of Open Access Journals (Sweden)

    Hamdi Alper Güngörmüş

    2014-03-01

    Full Text Available The purpose of this study was to investigate and compare the motivational factors that motivate individuals to the recreational exercise participation with regard to demographic variables. 302 male (55,1% and 246 female (44,9% with a total of 548 recreational exercise participants from 9 health and fitness centers, in Ankara, participated voluntarily to this study. “Recreational Exercise Motivation Measure” was used as means of data collection instrument. Independent Samples t-test was used to examine the mean differences with regard to gender and marital status considering 5 subscales. The results of independent samples t-test indicated that, there was a significant mean difference between males and females in “health” and status” (p<0,05. Results of the ANOVA analyses demonstrated statistically mean differences with “competition” subscales (p<0,05. Furthermore, there was a significant mean difference in 4 subscales except “health” with the effect of “marital regard to age (p<0,05. (competition, body shape/appearance, education (health (p<0,05, As a result of this study, “health”, “skill development” and ”body shape/appearance” were found to be the top three factors which motivate individuals to participate recreational exercise.

  4. INDIVIDUAL PSYCHOLOGICAL CHARACTERISTICS OF RAILWAYS OPERATORS OF DIFFERENT AGE GROUPS

    Directory of Open Access Journals (Sweden)

    Bugaeva V. M.

    2015-10-01

    Full Text Available The article presents the results of the study of some individual psychological characteristics of the drivers of rail transport in the age groups 25–34 and 35–45 years. We have identified a number of differences between the two age groups associated with both features individually-psychological sphere, and in the psycho-physiological features. Features of age-related psychological differences can be explained by the age characteristics of the representatives of each group; psycho-physiological features of age differences may reflect developed in the course of a long professional activity features. We have also developed adaptive strategies, consciously or unconsciously selected during the long-running monotonous activities and in small social groups (teams of drivers allow, on the one hand, higher quality performance of their professional duties, on the other — to avoid the harmful effects of stressful situations at work. It can be assumed that the composition of drivers age group 35– 45 years is the result of natural selection, when those who did not cope with this type of activity is simply dismissed or transferred to other kinds of professions

  5. INDIVIDUAL DIFFERENCES IN NATURAL LANGUAGE SWITCHING BETWEEN TWO LANGUAGES

    Directory of Open Access Journals (Sweden)

    Antoni eRodriguez-Fornells

    2012-01-01

    Full Text Available Language switching is omnipresent in bilingual persons. In fact, the ability to switch languages (code switching is a very fast, efficient and flexible process which seems to be a fundamental aspect of bilingual language processing. Here we aimed to characterize individual differences in language switching psychometrically and to create a reliable measure of this behavioral pattern by introducing a Bilingual Switching Questionnaire (BSWQ. As a working hypothesis and based on the previous literature on code switching we decomposed language switching into four constructs: (i L1 switching tendencies (the tendency to switch to L1 (L1-switch, (ii L2 switching tendencies (L2-switch; (iii Contextual Switch (CS, which indexes the frequency of switches usually triggered by a particular situation, topic or environment and, (iv Unintended Switch (US, which is measuring the lack of intention and awareness of the language switches. A total of 582 Spanish-Catalan bilingual university students was studied. Twelve items were selected (three for each construct. The correlation matrix was factor-analyzed using Minimum Rank Factor Analysis (MRFA followed by oblique Direct Oblimin rotation. The overall proportion of common variance explained by the four extracted factors was .86. Finally, in order to assess the external validity of the individual differences scored with the new questionnaire, we evaluated the correlations between these measures and several psychometric (language proficiency and behavioral measures related to cognitive and attentional control. The present study highlights the importance of assessing individual differences in language switching when studying the interface between cognitive control and bilingualism.

  6. A CONSIDERATION OF DIFFERENT INDIVIDUAL FACTORS IN CLASSROOM LANGUAGE TEACHING

    Institute of Scientific and Technical Information of China (English)

    1998-01-01

    Students’ individual differences pose a challenge to language teachers and influence the way in which a foreign language is learned. We are therefore invited to consider the role of our students’ personalities,motivation and cognitive styles in the language classroom. LANGUAGE teaching would be much easier if all students were alike. The number of instructional decisions would be greatly reduced; teaching methods would be rather simpler; lesson designs would not have to be modified; teachers would not have to consider alternative procedures; teacher-student interaction

  7. Herpes zoster at two different sites in the same individual

    Directory of Open Access Journals (Sweden)

    Kolalapudi Seetharam

    1995-01-01

    Full Text Available Herpes zoster occuring at two different sites in the same individual at the same time, involving more than two segments at each site has rarely been reported. We recently observed two such cases. The first patient was HIV-infected 10 year old haemophiliac who had zoster involving the distribution of the right C4, 5, 6 and left L 2, 3, 4 dermatomes and the second one was a 50 year old renal transplant recipient on immunosuppressive drugs who developed zoster at left C3, 4, 5 and left T 7, 8, 9.

  8. Distractor Inhibition Predicts Individual Differences in the Attentional Blink

    OpenAIRE

    Dux, Paul E.; René Marois

    2008-01-01

    BACKGROUND: The attentional blink (AB) refers to humans' impaired ability to detect the second of two targets (T2) in a rapid serial visual presentation (RSVP) stream of distractors if it appears within 200-600 ms of the first target (T1). Here we examined whether humans' ability to inhibit distractors in the RSVP stream is a key determinant of individual differences in T1 performance and AB magnitude. METHODOLOGY/PRINCIPAL FINDINGS: We presented subjects with RSVP streams (93.3 ms/item) of l...

  9. Sensitivity of alpha band ERD to individual differences in cognition.

    Science.gov (United States)

    Neubauer, Aljoscha C; Fink, Andreas; Grabner, Roland H

    2006-01-01

    According to the neural efficiency hypothesis, brighter individuals might be characterized by lower and topographically more differentiated brain activation than less intelligent individuals, presumably reflecting a more specialized recruitment of task-related areas. The findings of several studies analyzing the event-related desynchronization (ERD) in the (upper) alpha frequency band have corroborated and elaborated the original neural efficiency hypothesis. In this chapter, we review classical and recent findings and argue in favor of a more differentiated picture of this phenomenon, emphasizing the role of participants' sex, task complexity, and material specificity, as well as the importance to select an adequate external criterion (intelligence measure). Also, recent ERD findings related to emotional intelligence and creativity as well as recent studies focusing on practice, learning ability, and expertise are presented, which point to the need of a broader neurophysiological ability concept. The reviewed findings point at the high suitability of the ERD method to uncover consistent and stable individual differences in people's brain activation patterns when engaged in performing cognitively demanding tasks.

  10. Face aftereffects predict individual differences in face recognition ability.

    Science.gov (United States)

    Dennett, Hugh W; McKone, Elinor; Edwards, Mark; Susilo, Tirta

    2012-01-01

    Face aftereffects are widely studied on the assumption that they provide a useful tool for investigating face-space coding of identity. However, a long-standing issue concerns the extent to which face aftereffects originate in face-level processes as opposed to earlier stages of visual processing. For example, some recent studies failed to find atypical face aftereffects in individuals with clinically poor face recognition. We show that in individuals within the normal range of face recognition abilities, there is an association between face memory ability and a figural face aftereffect that is argued to reflect the steepness of broadband-opponent neural response functions in underlying face-space. We further show that this correlation arises from face-level processing, by reporting results of tests of nonface memory and nonface aftereffects. We conclude that face aftereffects can tap high-level face-space, and that face-space coding differs in quality between individuals and contributes to face recognition ability.

  11. An Opinion Interactive Model Based on Individual Persuasiveness.

    Science.gov (United States)

    Zhou, Xin; Chen, Bin; Liu, Liang; Ma, Liang; Qiu, Xiaogang

    2015-01-01

    In order to study the formation process of group opinion in real life, we put forward a new opinion interactive model based on Deffuant model and its improved models in this paper because current models of opinion dynamics lack considering individual persuasiveness. Our model has following advantages: firstly persuasiveness is added to individual's attributes reflecting the importance of persuasiveness, which means that all the individuals are different from others; secondly probability is introduced in the course of interaction which simulates the uncertainty of interaction. In Monte Carlo simulation experiments, sensitivity analysis including the influence of randomness, initial persuasiveness distribution, and number of individuals is studied at first; what comes next is that the range of common opinion based on the initial persuasiveness distribution can be predicted. Simulation experiment results show that when the initial values of agents are fixed, no matter how many times independently replicated experiments, the common opinion will converge at a certain point; however the number of iterations will not always be the same; the range of common opinion can be predicted when initial distribution of opinion and persuasiveness are given. As a result, this model can reflect and interpret some phenomena of opinion interaction in realistic society.

  12. Individual differences in sign language abilities in deaf children.

    Science.gov (United States)

    Meronen, Auli; Ahonen, Timo

    2008-01-01

    The study attempted to identify characteristics of individual differences in sign language abilities among deaf children. Connections between sign language skills and rapid serial naming, hand motor skills, and early fluency were investigated. The sample consisted of 85 Finnish deaf children. Their first language was sign language. Simple correlations and multiple linear-regression analysis demonstrated the effect of early language development and serial hand movements on sign language abilities. Other significant factors were serial fingertapping and serial naming. Heterogeneity in poor sign language users was noted. Although identifying learning disorders in deaf children is complicated, developmental difficulties can be discovered by appropriate measurements. The study confirmed the results of earlier research demonstrating that the features of deaf and hearing children's learning resemble each other. Disorders in signed and spoken languages may have similar bases despite their different modalities.

  13. 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.

  14. Individual differences predict low prevalence visual search performance.

    Science.gov (United States)

    Peltier, Chad; Becker, Mark W

    2017-01-01

    Critical real-world visual search tasks such as radiology and baggage screening rely on the detection of rare targets. When targets are rare, observers search for a relatively short amount of time and have a high miss rate, a pattern of results known as the low prevalence effect. Attempts to improve the search for rare targets have been unsuccessful or resulted in an increase in detections at the price of more false alarms. As an alternative to improving visual search performance through experimental manipulations, an individual differences approach found that those with higher working memory capacity were better at finding rare targets. We build on the individual differences approach and assess 141 observers' visual working memory capacity (vWMC), vigilance, attentional control, big five personality traits, and performance in both high and low prevalence search tasks. vWMC, vigilance, attentional control, high prevalence visual search performance, and level of introversion were all significant predictors of low prevalence search accuracy, and together account for more than 50% of the variance in search performance. With the exception of vigilance, these factors are also significant predictors of reaction time; better performance was associated with longer reaction times, suggesting these factors identify observers who maintain relatively high quitting thresholds, even with low target prevalence. Our results suggest that a quick and easy-to-administer battery of tasks can identify observers who are likely to perform well in low prevalence search tasks, and these predictor variables are associated with higher quitting thresholds, leading to higher accuracy.

  15. 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.

  16. Prospective memory, personality, and individual differences in cognition

    Directory of Open Access Journals (Sweden)

    Bob eUttl

    2013-03-01

    Full Text Available 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 prospective memory 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.

  17. 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.

  18. Individual Differences in Spatial Orientation Performances: An Eye Tracking Study

    Directory of Open Access Journals (Sweden)

    Sacide Güzin Mazman

    2013-08-01

    Full Text Available This paper includes two studies. In study 1, the computerized version of Spatial Orientation Test (Kozhevnikov & Hegarty, 2001 was standardized for determining the norm values for Turkish undergraduate students as well as demonstrating the reliability and validity of the test. In Study 1, 101 undergraduate students from two different departments were recruited and the data were collected with computerized spatial orientation test together with a demographic information form. Descriptive statistics, independent sample t test and one way ANOVA were used in data analysis. Statistical analyses revealed out that gender and years of computer experience have significant effect on spatial orientation ability scores. Test-retest reliability coefficient was found for total accuracy score as r= .778 and r=.634 for total reaction time. As a result of discriminant validity study, the correlation between the spatial orientation and mental rotation test scores was found to be very low and not significant. In study 2, individual differences between low and high spatial orientation ability groups during performing “Spatial Orientation Test” were examined through eye movements. Five high and five low spatial orientation ability level students were asked to participate in the second study. While performing Spatial Orientation Test, their eye movements were recorded. The findings indicated that there were significant differences in eye movements between different spatial orientation ability levels in terms of fixation duration. Furthermore it was found that high and low level spatial orientation level groups solved problems with different solution patterns.

  19. Musical training, individual differences and the cocktail party problem.

    Science.gov (United States)

    Swaminathan, Jayaganesh; Mason, Christine R; Streeter, Timothy M; Best, Virginia; Kidd, Gerald; Patel, Aniruddh D

    2015-06-26

    Are musicians better able to understand speech in noise than non-musicians? Recent findings have produced contradictory results. Here we addressed this question by asking musicians and non-musicians to understand target sentences masked by other sentences presented from different spatial locations, the classical 'cocktail party problem' in speech science. We found that musicians obtained a substantial benefit in this situation, with thresholds ~6 dB better than non-musicians. Large individual differences in performance were noted particularly for the non-musically trained group. Furthermore, in different conditions we manipulated the spatial location and intelligibility of the masking sentences, thus changing the amount of 'informational masking' (IM) while keeping the amount of 'energetic masking' (EM) relatively constant. When the maskers were unintelligible and spatially separated from the target (low in IM), musicians and non-musicians performed comparably. These results suggest that the characteristics of speech maskers and the amount of IM can influence the magnitude of the differences found between musicians and non-musicians in multiple-talker "cocktail party" environments. Furthermore, considering the task in terms of the EM-IM distinction provides a conceptual framework for future behavioral and neuroscientific studies which explore the underlying sensory and cognitive mechanisms contributing to enhanced "speech-in-noise" perception by musicians.

  20. Individual Differences in the Potential and Realized Developmental Plasticity of Personality Traits

    Directory of Open Access Journals (Sweden)

    Judy eStamps

    2014-10-01

    Full Text Available Changes in personality over ontogeny can occur even when every agent (individual or genotype is exposed to the same set of cues, experiences or environmental conditions. A recent Bayesian model (Stamps and Krishnan, in press shows how individual differences in the means and variances of prior distributions of estimates of variables such as danger can generate predictable individual differences in behavioral developmental trajectories, and predictable changes in the differential consistency (broad-sense repeatability of behavior over ontogeny, even if every subject is reared and maintained under the same conditions. We use this model to highlight the distinction between potential plasticity (the ability of an agent to change its phenotype in response to different types of experience and realized plasticity (the extent to which an agent’s phenotype actually changes in response to a specific experience, and to demonstrate why the realized behavioral developmental plasticity of a given agent might vary as a function of the type of cues to which that agent was exposed over ontogeny. We describe two commonly used experimental protocols for studying individual differences in developmental plasticity (within-individual versus replicate individual designs, discuss the advantages and disadvantages of each for investigating individual differences in the developmental plasticity of personality traits, and explain why replicate individual designs provide better estimates than within-individual designs of the potential developmental plasticity of behavioral traits. More generally, we suggest that a Bayesian approach to development, especially one which assumes that individuals differ with respect to the information provided by their immediate and distant ancestors, can provide valuable insights into how genes, epigenetic factors, maternal effects and personal experiences might combine across the lifetime to affect the development of personality and other

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

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    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.

  2. 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.

  3. 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). Wh...

  4. Centrality and individual differences in the meaning of daily hassles.

    Science.gov (United States)

    Gruen, R J; Folkman, S; Lazarus, R S

    1988-12-01

    In this study we introduce the concept of centrality in an attempt to assess individual differences in the meaning underlying daily hassles. Central hassles are defined as those which reflect important ongoing themes or problems in the person's life. The characteristics of central hassles, and their role in psychological and somatic health, were assessed in a sample of 150 community-residing men and women. The results indicate that central hassles vary in content from person to person and touch more on problems with personal needs and deficits in coping skills compared to noncentral hassles. The dimension of centrality was found to play a significant role in the prediction of psychological symptoms. Although the empirical case for the importance of centrality in the stress-illness relationship is inconclusive due to problems of confounding and a cross-sectional rather than longitudinal design, the ideas presented appear promising and provide a basis for further research on psychological vulnerability to stress.

  5. Individual Differences in Persuadability in the Health Promotion Domain

    Science.gov (United States)

    Kaptein, Maurits; Lacroix, Joyca; Saini, Privender

    This paper examines the behavioral consequences of individual differences in persuadability in the health promotion domain. We use a 7-item persuadability instrument to determine participants persuadability score. Based on this score two groups are created: the low and high persuadables. Subsequently, we present 2 studies that test the responses to health-related persuasive messages of both low and high persuadables. The results consistently show that high persuadables comply more to messages with a persuasive content as compared to a neutral message than low persuadables. Even more, both studies indicate lower compliance by low persuadables when persuasive messages are employed. Implications of this possible detrimental effect of the use of persuasive messages for low persuadables are discussed.

  6. Figuring out the figurative: Individual differences in literary metaphor comprehension

    Directory of Open Access Journals (Sweden)

    Altaras-Dimitrijević Ana

    2007-01-01

    Full Text Available This paper explores the cognitive and affective-conative correlates of metaphor comprehension. We first introduce the concept of metaphor by describing its essential features and functions. Then, we give a short review of key findings derived from cognitive and developmental studies of metaphor comprehension. Finally, we discuss individual differences in metaphoric skill and sensitivity and present the results of an empirical investigation in which we sought to determine the relationship between literary metaphor comprehension, the subjective experience of metaphors and the readers’ verbal intelligence and personality traits. On the basis of our research findings, it is argued that metaphoric ability represents a central facet of intelligence and that the Test of Literary Metaphor Comprehension designed in our study may be viewed as a valid measure of verbal ability. .

  7. Individual Differences in Nonsymbolic Ratio Processing Predict Symbolic Math Performance.

    Science.gov (United States)

    Matthews, Percival G; Lewis, Mark Rose; Hubbard, Edward M

    2016-02-01

    What basic capacities lay the foundation for advanced numerical cognition? Are there basic nonsymbolic abilities that support the understanding of advanced numerical concepts, such as fractions? To date, most theories have posited that previously identified core numerical systems, such as the approximate number system (ANS), are ill-suited for learning fraction concepts. However, recent research in developmental psychology and neuroscience has revealed a ratio-processing system (RPS) that is sensitive to magnitudes of nonsymbolic ratios and may be ideally suited for supporting fraction concepts. We provide evidence for this hypothesis by showing that individual differences in RPS acuity predict performance on four measures of mathematical competence, including a university entrance exam in algebra. We suggest that the nonsymbolic RPS may support symbolic fraction understanding much as the ANS supports whole-number concepts. Thus, even abstract mathematical concepts, such as fractions, may be grounded not only in higher-order logic and language, but also in basic nonsymbolic processing abilities.

  8. Individual differences in time perspective predict autonoetic experience.

    Science.gov (United States)

    Arnold, Kathleen M; McDermott, Kathleen B; Szpunar, Karl K

    2011-09-01

    Tulving (1985) posited that the capacity to remember is one facet of a more general capacity-autonoetic (self-knowing) consciousness. Autonoetic consciousness was proposed to underlie the ability for "mental time travel" both into the past (remembering) and into the future to envision potential future episodes (episodic future thinking). The current study examines whether individual differences can predict autonoetic experience. Specifically, the Zimbardo Time Perspective Inventory (ZTPI, Zimbardo & Boyd, 1999) was administered to 133 undergraduate students, who also rated phenomenological experiences accompanying autobiographical remembering and episodic future thinking. Scores on two of the five subscales of the ZTPI (Future and Present-Hedonistic) predicted the degree to which people reported feelings of mentally traveling backward (or forward) in time and the degree to which they reported re- or pre-experiencing the event, but not ten other rated properties less related to autonoetic consciousness.

  9. Speech rhythm sensitivity and musical aptitude: ERPs and individual differences.

    Science.gov (United States)

    Magne, Cyrille; Jordan, Deanna K; Gordon, Reyna L

    2016-02-01

    This study investigated the electrophysiological markers of rhythmic expectancy during speech perception. In addition, given the large literature showing overlaps between cognitive and neural resources recruited for language and music, we considered a relation between musical aptitude and individual differences in speech rhythm sensitivity. Twenty adults were administered a standardized assessment of musical aptitude, and EEG was recorded as participants listened to sequences of four bisyllabic words for which the stress pattern of the final word either matched or mismatched the stress pattern of the preceding words. Words with unexpected stress patterns elicited an increased fronto-central mid-latency negativity. In addition, rhythm aptitude significantly correlated with the size of the negative effect elicited by unexpected iambic words, the least common type of stress pattern in English. The present results suggest shared neurocognitive resources for speech rhythm and musical rhythm.

  10. 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.

  11. 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.

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

    Directory of Open Access Journals (Sweden)

    Annabel D Nijhof

    Full Text Available 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.

  13. 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.

  14. 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

  15. Individual differences in hemispheric preference and emotion regulation difficulties

    Directory of Open Access Journals (Sweden)

    Garima Gupta

    2011-01-01

    Full Text Available Background: Hemisphericity or individual difference in the preference to use the left or the right hemispheric mode of information processing has been associated with various emotion-related differences. For example, the right hemisphericity has been linked with inhibition of emotional expression, feeling of tension, greater impulsivity etc. These observations suggest that right hemisphericity may be associated with greater difficulties in regulating emotions. However, direct empirical tests of such theoretical proposition are very thin. Aim: In view of this, the present study aims to investigate how and to what extent individual difference in hemispheric preference relate to emotion regulation. Materials and Methods: Thirty-two right-handed male subjects in the age range 18 to 20 years were assessed on self-report measures of hemispheric preference and emotion regulation difficulties. The correlation between dimensions of hemispheric preference and difficulties in regulating emotions was computed. A series of stepwise multiple regression analyses were also done to explore the relative significance of various dimensions of hemispheric preference in predicting emotion regulation difficulties. Results: The findings revealed that in general a preference for the right hemispheric mode of information processing was associated with greater emotion regulation difficulties. The correlation analysis indicated that while impulse control difficulties and difficulties in engaging goal directed behavior was associated with preference for almost all the right hemispheric mode of information processing, the nonacceptance of emotional responses and limited access to emotion regulation was related to preference for only global/synthetic (a right hemispheric mode of information processing. Similarly, the lack of emotional clarity facet of emotion regulation difficulties correlated significantly with a preference for the emotional mode of information processing

  16. The role of individual differences in cognitive training and transfer.

    Science.gov (United States)

    Jaeggi, Susanne M; Buschkuehl, Martin; Shah, Priti; Jonides, John

    2014-04-01

    Working memory (WM) training has recently become a topic of intense interest and controversy. Although several recent studies have reported near- and far-transfer effects as a result of training WM-related skills, others have failed to show far transfer, suggesting that generalization effects are elusive. Also, many of the earlier intervention attempts have been criticized on methodological grounds. The present study resolves some of the methodological limitations of previous studies and also considers individual differences as potential explanations for the differing transfer effects across studies. We recruited intrinsically motivated participants and assessed their need for cognition (NFC; Cacioppo & Petty Journal of Personality and Social Psychology 42:116-131, 1982) and their implicit theories of intelligence (Dweck, 1999) prior to training. We assessed the efficacy of two WM interventions by comparing participants' improvements on a battery of fluid intelligence tests against those of an active control group. We observed that transfer to a composite measure of fluid reasoning resulted from both WM interventions. In addition, we uncovered factors that contributed to training success, including motivation, need for cognition, preexisting ability, and implicit theories about intelligence.

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

    Directory of Open Access Journals (Sweden)

    Susan B Perlman

    Full Text Available BACKGROUND: 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. METHODOLOGY/PRINCIPAL FINDINGS: 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. CONCLUSIONS/SIGNIFICANCE: 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.

  18. Distractor inhibition predicts individual differences in the attentional blink.

    Directory of Open Access Journals (Sweden)

    Paul E Dux

    Full Text Available BACKGROUND: The attentional blink (AB refers to humans' impaired ability to detect the second of two targets (T2 in a rapid serial visual presentation (RSVP stream of distractors if it appears within 200-600 ms of the first target (T1. Here we examined whether humans' ability to inhibit distractors in the RSVP stream is a key determinant of individual differences in T1 performance and AB magnitude. METHODOLOGY/PRINCIPAL FINDINGS: We presented subjects with RSVP streams (93.3 ms/item of letters containing white distractors, a red T1 and a green T2. Subjects' ability to suppress distractors was assessed by determining the extent to which their second target performance was primed by a preceding distractor that shared the same identity as T2. Individual subjects' magnitude of T2 priming from this distractor was found to be negatively correlated with their T1 accuracy and positively related to their AB magnitude. In particular, subjects with attenuated ABs showed negative priming (i.e., worse T2 performance when the priming distractor appeared in the RSVP stream compared to when it was absent, whereas those with large ABs displayed positive priming (i.e., better T2 performance when the priming distractor appeared in the RSVP stream compared to when it was absent. Thus, a subject's ability to suppress distractors, as assessed by T2 priming magnitude, predicted both their T1 performance and AB magnitude. CONCLUSIONS/SIGNIFICANCE: These results confirm that distractor suppression plays a key role in RSVP target selection and support the hypothesis that the AB results, at least in part, from a failure of distractor inhibition.

  19. 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.

  20. Considering ERP difference scores as individual difference measures: Issues with subtraction and alternative approaches.

    Science.gov (United States)

    Meyer, Alexandria; Lerner, Matthew D; De Los Reyes, Andres; Laird, Robert D; Hajcak, Greg

    2017-01-01

    There is growing interest in psychophysiological and neural correlates of psychopathology, personality, and other individual differences. Many studies correlate a criterion individual difference variable (e.g., anxiety) with a psychophysiological measurement derived by subtracting scores taken from two within-subject conditions. These subtraction-based difference scores are intended to increase specificity by isolating variability of interest. Using data on the error-related negativity (ERN) and correct response negativity (CRN) in relation to generalized anxiety disorder (GAD), we highlight several conceptual and practical issues with subtraction-based difference scores and propose alternative approaches based on regression. We show that ERN and CRN are highly correlated, and that the ΔERN (i.e., ERN - CRN) is correlated in opposite directions both with ERN and CRN. Bivariate analyses indicate that GAD is related to ΔERN and ERN, but not CRN. We first show that, by using residualized scores, GAD relates both to a larger ERN and smaller CRN. Moreover, by probing the interaction of ERN and CRN, we show that the relationship between GAD and ERN varies by CRN. These latter findings are not evident when using traditional subtraction-based difference scores. We then completed follow-up analyses that suggested that an increased P300 in anxious individuals gave rise to the apparent anxiety/CRN relationship observed. These findings have important conceptual implications for facilitating the interpretability of results from individual difference studies of psychophysiology.

  1. 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.

  2. Stress Process Model for Individuals with Dementia

    Science.gov (United States)

    Judge, Katherine S.; Menne, Heather L.; Whitlatch, Carol J.

    2010-01-01

    Purpose: Individuals with dementia (IWDs) face particular challenges in managing and coping with their illness. The experience of dementia may be affected by the etiology, stage, and severity of symptoms, preexisting and related chronic conditions, and available informal and formal supportive services. Although several studies have examined…

  3. Model and Analysis of Individual Rehearsals

    DEFF Research Database (Denmark)

    Jensen, Kristoffer; Frimodt-Møller, Søren

    2013-01-01

    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. Individual differences in adult handwritten spelling-to-dictation

    Directory of Open Access Journals (Sweden)

    Patrick eBONIN

    2013-07-01

    Full Text Available We report an investigation of individual differences in handwriting latencies and number of errors in a spelling-to-dictation task. Eighty adult participants wrote a list of 164 spoken words (presented in two sessions. The participants were also evaluated on a vocabulary test (Deltour, 1993. Various multiple regression analyses were performed (on both writing latency and errors. The analysis of the item means showed that the reliable predictors of spelling latencies were acoustic duration, cumulative word frequency, phonology-to-orthographic (PO consistency, the number of letters in the word and the interaction between cumulative word frequency, PO consistency and imageability. (Error rates were also predicted by frequency, consistency, length and the interaction between cumulative word frequency, PO consistency and imageability. The analysis of the participant means (and trials showed that (i there was both within- and between-session reliability across the sets of items, (ii there was no trade-off between the utilization of lexical and nonlexical information, and (iii participants with high vocabulary knowledge were more accurate (and somewhat faster, and had a differential sensitivity to certain stimulus characteristics, than those with low vocabulary knowledge. We discuss the implications of these findings for theories of orthographic word production.

  5. 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.

  6. 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

  7. Effects of differences in nasal anatomy on airflow distribution: a comparison of four individuals at rest.

    Science.gov (United States)

    Segal, Rebecca A; Kepler, Grace M; Kimbell, Julia S

    2008-11-01

    Differences in nasal anatomy among human subjects may cause significant differences in respiratory airflow patterns and subsequent dosimetry of inhaled gases and particles in the respiratory tract. This study used computational fluid dynamics (CFD) to study inter-individual differences in nasal airflow among four healthy individuals. Magnetic resonance imaging (MRI) scans were digitized and nasal-surface-area-to-volume ratios (SAVR) were calculated for 15 adults. Two males and two females, representative of the range of SAVR values, were selected for flow analysis. Nasal CFD models were constructed for each subject by a semi-automated process that provided input to a commercial mesh generator to generate structured hexahedral meshes (Gambit, Fluent, Inc., Lebanon, NH, USA). Steady-state inspiratory laminar airflow at 15 L/min was calculated using commercial CFD software (FIDAP, Fluent, Inc., Lebanon, NH, USA). Streamline patterns, velocities, and helicity values were compared. In all subjects, the majority of flow passed through the middle and ventral regions of the nasal passages; however, the amount and location of swirling flow differed among individuals. Cross-sectional flow allocation analysis also indicated inter-individual differences. Laboratory water-dye experiments confirmed streamlines and velocity magnitudes predicted by the computational model. These results suggest that significant inter-individual differences exist in bulk airflow patterns in the nose.

  8. 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.

  9. Are Some Negotiators Better Than Others? Individual Differences in Bargaining Outcomes

    Science.gov (United States)

    Elfenbein, Hillary Anger; Curhan, Jared R.; Eisenkraft, Noah; Shirako, Aiwa; Baccaro, Lucio

    2008-01-01

    The authors address the long-standing mystery of stable individual differences in negotiation performance, on which intuition and conventional wisdom have clashed with inconsistent empirical findings. The present study used the Social Relations Model to examine individual differences directly via consistency in performance across multiple negotiations and to disentangle the roles of both parties within these inherently dyadic interactions. Individual differences explained a substantial 46% of objective performance and 19% of subjective performance in a mixed-motive bargaining exercise. Previous work may have understated the influence of individual differences because conventional research designs require specific traits to be identified and measured. Exploratory analyses of a battery of traits revealed few reliable associations with consistent individual differences in objective performance—except for positive beliefs about negotiation, positive affect, and concern for one's outcome, each of which predicted better performance. Findings suggest that the field has large untapped potential to explain substantial individual differences. Limitations, areas for future research, and practical implications are discussed. PMID:21720453

  10. Investigating systematic individual differences in sleep-deprived performance on a high-fidelity flight simulator.

    Science.gov (United States)

    Van Dongen, Hans P A; Caldwell, John A; Caldwell, J Lynn

    2006-05-01

    Laboratory research has revealed considerable systematic variability in the degree to which individuals' alertness and performance are affected by sleep deprivation. However, little is known about whether or not different populations exhibit similar levels of individual variability. In the present study, we examined individual variability in performance impairment due to sleep loss in a highly select population of militaryjet pilots. Ten active-duty F-117 pilots were deprived of sleep for 38 h and studied repeatedly in a high-fidelity flight simulator. Data were analyzed with a mixed-model ANOVA to quantify individual variability. Statistically significant, systematic individual differences in the effects of sleep deprivation were observed, even when baseline differences were accounted for. The findings suggest that highly select populations may exhibit individual differences in vulnerability to performance impairment from sleep loss just as the general population does. Thus, the scientific and operational communities' reliance on group data as opposed to individual data may entail substantial misestimation of the impact of job-related stressors on safety and performance.

  11. Individual differences in learning to teach : relating cognition, regulation and affect

    NARCIS (Netherlands)

    Oosterheert, IE; Vermunt, JD

    2001-01-01

    The purpose of this study was to describe individual differences in learning to teach. Thirty secondary student teachers were interviewed about several components of their learning: mental models of learning to teach, learning activities, regulation in general, emotion regulation in particular, idea

  12. 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…

  13. Inter- and intra-individual differences in teachers' self-efficacy : A multilevel factor exploration

    NARCIS (Netherlands)

    Zee, M.; Koomen, H.M.Y.; Jellesma, F.C.; Geerlings, J.; de Jong, P.F.

    2016-01-01

    This study explored inter- and intra-individual differences in teachers' self-efficacy (TSE) by adapting Tschannen-Moran and Woolfolk Hoy's (2001) Teachers' Sense of Efficacy Scale (TSES) to the domain- and student-specific level. Multilevel structural equation modeling was used to evaluate the fact

  14. Individual differences in learning to teach : relating cognition, regulation and affect

    NARCIS (Netherlands)

    Oosterheert, IE; Vermunt, JD

    The purpose of this study was to describe individual differences in learning to teach. Thirty secondary student teachers were interviewed about several components of their learning: mental models of learning to teach, learning activities, regulation in general, emotion regulation in particular,

  15. Phonological Development from Babbling to Speech: Common Tendencies and Individual Differences.

    Science.gov (United States)

    Vihman, Marilyn May; And Others

    1986-01-01

    Using Locke's 1983 model, analyzes one tendency, consonant use in babbling and early words, and phonological word-selection patterns in 10 children, aged 8 to 16 months. Individual differences were found in all three domains analyzed, with some increase in uniformity across subjects with increasing knowledge of language. (Author/SED)

  16. Inter- and intra-individual differences in teachers' self-efficacy : A multilevel factor exploration

    NARCIS (Netherlands)

    Zee, M.; Koomen, H.M.Y.; Jellesma, F.C.; Geerlings, J.; de Jong, P.F.

    2016-01-01

    This study explored inter- and intra-individual differences in teachers' self-efficacy (TSE) by adapting Tschannen-Moran and Woolfolk Hoy's (2001) Teachers' Sense of Efficacy Scale (TSES) to the domain- and student-specific level. Multilevel structural equation modeling was used to evaluate the fact

  17. Individual differences in learning to teach : relating cognition, regulation and affect

    NARCIS (Netherlands)

    Oosterheert, IE; Vermunt, JD

    2001-01-01

    The purpose of this study was to describe individual differences in learning to teach. Thirty secondary student teachers were interviewed about several components of their learning: mental models of learning to teach, learning activities, regulation in general, emotion regulation in particular, idea

  18. IBSEM: An Individual-Based Atlantic Salmon Population Model.

    Directory of Open Access Journals (Sweden)

    Marco Castellani

    Full Text Available Ecology and genetics can influence the fate of individuals and populations in multiple ways. However, to date, few studies consider them when modelling the evolutionary trajectory of populations faced with admixture with non-local populations. For the Atlantic salmon, a model incorporating these elements is urgently needed because many populations are challenged with gene-flow from non-local and domesticated conspecifics. We developed an Individual-Based Salmon Eco-genetic Model (IBSEM to simulate the demographic and population genetic change of an Atlantic salmon population through its entire life-cycle. Processes such as growth, mortality, and maturation are simulated through stochastic procedures, which take into account environmental variables as well as the genotype of the individuals. IBSEM is based upon detailed empirical data from salmon biology, and parameterized to reproduce the environmental conditions and the characteristics of a wild population inhabiting a Norwegian river. Simulations demonstrated that the model consistently and reliably reproduces the characteristics of the population. Moreover, in absence of farmed escapees, the modelled populations reach an evolutionary equilibrium that is similar to our definition of a 'wild' genotype. We assessed the sensitivity of the model in the face of assumptions made on the fitness differences between farm and wild salmon, and evaluated the role of straying as a buffering mechanism against the intrusion of farm genes into wild populations. These results demonstrate that IBSEM is able to capture the evolutionary forces shaping the life history of wild salmon and is therefore able to model the response of populations under environmental and genetic stressors.

  19. Sex Differences and Individual Differences in Human Facilitative and Preventive Courtship

    Directory of Open Access Journals (Sweden)

    Steven Arnocky

    2014-12-01

    Full Text Available Although cooperative mating strategies have been observed in other species, the extent to which men and women act to facilitate the mating success of others has been under-researched, especially among unrelated individuals. The present study addressed this gap in knowledge by exploring potential sex differences and individual differences in attitudes toward facilitating and preventing friends’ mating among 256 heterosexual undergraduate men and women. Results showed that women were more likely than men to express attitudes toward preventing the sexuality of friends, whereas no sex difference existed in facilitative mating. For both men and women, positive reciprocity beliefs and high self-perceived mate-value predicted positive attitudes toward facilitative mating. Among women, preventive mating was predicted by low sociosexuality and high intrasexual (within-sex competitiveness.

  20. Comparing different dynamic stall models

    Energy Technology Data Exchange (ETDEWEB)

    Holierhoek, J.G. [Unit Wind Energy, Energy research Centre of the Netherlands, ZG, Petten (Netherlands); De Vaal, J.B.; Van Zuijlen, A.H.; Bijl, H. [Aerospace Engineering, Delft University of Technology, Delft (Netherlands)

    2012-07-16

    The dynamic stall phenomenon and its importance for load calculations and aeroelastic simulations is well known. Different models exist to model the effect of dynamic stall; however, a systematic comparison is still lacking. To investigate if one is performing better than another, three models are used to simulate the Ohio State University measurements and a set of data from the National Aeronautics and Space Administration Ames experimental study of dynamic stall and compare results. These measurements were at conditions and for aerofoils that are typical for wind turbines, and the results are publicly available. The three selected dynamic stall models are the ONERA model, the Beddoes-Leishman model and the Snel model. The simulations show that there are still significant differences between measurements and models and that none of the models is significantly better in all cases than the other models. Especially in the deep stall regime, the accuracy of each of the dynamic stall models is limited.

  1. 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

  2. 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; Süss, Heinz-Martin; Wittmann, Werner W

    2007-08-01

    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 of the 3 ex-Gaussian parameters and for 3 parameters central to the diffusion model using structural equation modeling for a battery of choice reaction tasks. These factors had differential relations to criterion constructs. Parameters reflecting the tail of the distribution (i.e., tau in the ex-Gaussian and drift rate in the diffusion model) were the strongest unique predictors of working memory, reasoning, and psychometric speed. Theories of controlled attention and binding are discussed as potential theoretical explanations.

  3. Interactions between Individual Differences, Treatments, and Structures in SLA

    Science.gov (United States)

    DeKeyser, Robert

    2012-01-01

    For decades educational psychologists have bemoaned the black box approach of much research on learning, that is, the focus on product rather than process, and the absence of fine-grained analysis of the learning process in the individual. One way that progress has been made on this point in the last couple of decades is through cognitive…

  4. Individual Differences in Military Training Environments: Four Areas of Research

    Science.gov (United States)

    1987-01-30

    and Caylor, J.S. (1971). Effects of aptitude (AFQT). job experience, and literacy on job performance: Summary of HUMRRO work units utility and...Review of Psychology, 35, 519-55!. Williams, R.J. and Rimland, B. (1977). Individuality. In Encyclopedia of Psychiatry, Neurology and Psychoanalysis . New

  5. 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 inform

  6. 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…

  7. The Croton-Yorktown Model of Individualized Earth Science.

    Science.gov (United States)

    Matthias, George F.; Snyder, Edward B.

    1980-01-01

    The individualized learning model, discussed in this article, uses an efficient feedback mechanism which incorporates an innovative student evaluation program and a unique system of classroom management. The design provides a model for monitoring student progress. (Author/SA)

  8. A neural network evaluation model for individual thermal comfort

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Weiwei; Lian, Zhiwei; Zhao, Bo [Institute of Refrigeration and Cryogenics, Shanghai Jiao Tong University, Shanghai 200240 (China)

    2007-10-15

    An evaluation model for individual thermal comfort is presented based on the BP neural network. The train data came from a thermal comfort survey. The evaluation results of the model showed a good match with the subject's real thermal sensation, which indicated that the model can be used to evaluate individual thermal comfort rightly. Taken a room air conditioner as an example, the application of the NNEM in creating a microenvironment for individual was discussed. The result showed that the NNEM can play an important role of connecting individual thermal comfort with the control on the air conditioner. (author)

  9. Stochastic wind turbine modeling for individual pitch control

    DEFF Research Database (Denmark)

    Thomsen, Sven Creutz; Niemann, Hans Henrik; Poulsen, Niels Kjølstad

    2009-01-01

    By pitching the blades of a wind turbine individually it is possible to attenuate the asymmetric loads caused by a non-uniform wind field - this is denoted individual pitch control. In this work we investigate how to set up a simplified stochastic and deterministic description of the wind...... and a simplified description of the aerodynamics with sufficient detail to design model-based individual pitch controllers. Combined with a simplified model of the wind turbine, we exemplify how to use the model elements to systematically design an individual pitch controller. The design is investigated...

  10. Acculturation: When Individuals and Groups of Different Cultural Backgrounds Meet.

    Science.gov (United States)

    Sam, David L; Berry, John W

    2010-07-01

    In cross-cultural psychology, one of the major sources of the development and display of human behavior is the contact between cultural populations. Such intercultural contact results in both cultural and psychological changes. At the cultural level, collective activities and social institutions become altered, and at the psychological level, there are changes in an individual's daily behavioral repertoire and sometimes in experienced stress. The two most common research findings at the individual level are that there are large variations in how people acculturate and in how well they adapt to this process. Variations in ways of acculturating have become known by the terms integration, assimilation, separation, and marginalization. Two variations in adaptation have been identified, involving psychological well-being and sociocultural competence. One important finding is that there are relationships between how individuals acculturate and how well they adapt: Often those who integrate (defined as being engaged in both their heritage culture and in the larger society) are better adapted than those who acculturate by orienting themselves to one or the other culture (by way of assimilation or separation) or to neither culture (marginalization). Implications of these findings for policy and program development and for future research are presented.

  11. Combining information from ancestors and personal experiences to predict individual differences in developmental trajectories.

    Science.gov (United States)

    Stamps, Judy A; Krishnan, V V

    2014-11-01

    A persistent question in biology is how information from ancestors combines with personal experiences over the lifetime to affect the developmental trajectories of phenotypic traits. We address this question by modeling individual differences in behavioral developmental trajectories on the basis of two assumptions: (1) differences among individuals in the behavior expressed at birth or hatching are based on information from their ancestors (via genes, epigenes, and prenatal maternal effects), and (2) information from ancestors is combined with information from personal experiences over ontogeny via Bayesian updating. The model predicts relationships between the means and the variability of the behavior expressed by neonates and the subsequent developmental trajectories of their behavior when every individual is reared under the same environmental conditions. Several predictions of the model are supported by data from previous studies of behavioral development, for example, that the temporal stability of personality will increase with age and that the intercepts and slopes of developmental trajectories for boldness will be negatively correlated across individuals or genotypes when subjects are raised in safe environments. We describe how other specific predictions of the model can be used to test the hypothesis that information from ancestors and information from personal experiences are combined via nonadditive, Bayesian-like processes.

  12. Is the fluency of language outputs related to individual differences in intelligence and executive function?

    Science.gov (United States)

    Engelhardt, Paul E; Nigg, Joel T; Ferreira, Fernanda

    2013-10-01

    There has been little research on the fluency of language production and individual difference variables, such as intelligence and executive function. In this study, we report data from 106 participants who completed a battery of standardized cognitive tasks and a sentence production task. For the sentence production task, participants were presented with two objects and a verb and their task was to formulate a sentence. Four types of disfluency were examined: filled pauses (e.g. uh, um), unfilled pauses, repetitions, and repairs. Repetitions occur when the speaker suspends articulation and then repeats the previous word/phrase, and repairs occur when the speaker suspends articulation and then starts over with a different word/phrase. Hierarchical structural equation modeling revealed a significant relationship between repair disfluencies and inhibition. Conclusions focus on the role of individual differences in cognitive ability and their role in models and theories of language production.

  13. Is the fluency of language outputs related to individual differences in intelligence and executive function?

    Science.gov (United States)

    Engelhardt, Paul E.; Nigg, Joel T.; Ferreira, Fernanda

    2013-01-01

    There has been little research on the fluency of language production and individual differences variables, such as intelligence and executive function. In this study, we report data from 106 participants who completed a battery of standardized cognitive tasks and a sentence production task. For the sentence production task, participants were presented with two objects and a verb and their task was to formulate a sentence. Four types of disfluency were examined: filled pauses (e.g. uh, um), unfilled pauses, repetitions, and repairs. Repetitions occur when the speaker suspends articulation and then repeats the previous word/phrase, and repairs occur when the speaker suspends articulation and then starts over with a different word/phrase. Hierarchical structural equation modeling revealed a significant relationship between repair disfluencies and inhibition. Conclusions focus on the role of individual differences in cognitive ability and their role in models and theories of language production. PMID:24018099

  14. Comparing the effects of different individualized music interventions for elderly individuals with severe dementia

    OpenAIRE

    Sakamoto, Mayumi; Ando, Hiroshi; Tsutou, Akimitsu

    2013-01-01

    Background: Individuals with dementia often experience poor quality of life (QOL) due to behavioral and psychological symptoms of dementia (BPSD). Music therapy can reduce BPSD, but most studies have focused on patients with mild to moderate dementia. We hypothesized that music intervention would have beneficial effects compared with a no-music control condition, and that interactive music intervention would have stronger effects than passive music intervention. Methods: Thirty-nine individua...

  15. The PIC [Process Individualization Curriculum] Model: Structure with Humanistic Goals.

    Science.gov (United States)

    Gow, Doris T.

    This paper describes a curriculum design model to train research and development personnel under USOE-NIE funding. This design model, called PIC (Process Individualization Curriculum), was chosen for coverting on-campus courses to extra-mural self-instructional courses. The curriculum specialists who work with professors to individualize their…

  16. Individual Differences in Eye-Movements During Reading: Working Memory and Speed-of-Processing Effects.

    Science.gov (United States)

    Traxler, Matthew J; Long, Debra L; Tooley, Kristen M; Johns, Clinton L; Zirnstein, Megan; Jonathan, Eunike

    Theories of eye-movement control in reading should ultimately describe how differences in knowledge and cognitive abilities affect reading and comprehension. Current mathematical models of eye-movement control do not yet incorporate individual differences as a source of variation in reading, although developmental and group-difference effects have been studied. These models nonetheless provide an excellent foundation for describing and explaining how and why patterns of eye-movements differ across readers (e.g., Rayner, Chace, & Ashby, 2006). Our focus in this article is on two aspects of individual variation: global processing speed (e.g., Salthouse, 1996) and working-memory capacity (e.g., Just & Carpenter, 1992). Using Hierarchical Linear Modeling (HLM) (Raudenbush & Bryk, 2001), we tested the extent to which overall reading speed and working-memory capacity moderate the degree to which syntactic and semantic information affect fixation times. Previous published data (Traxler et al., 2005) showed that working memory capacity and syntactic complexity interacted to determine fixation times in an eye-movement monitoring experiment. In a new set of models based on this same data set, we found that working-memory capacity interacted with sentence-characteristic variables only when processing speed was not included in the model. We interpret these findings with respect to current accounts of sentence processing and suggest how they might be incorporated into eye-movement control models.

  17. The Understanding and Comment of Individual Learner Difference

    Institute of Scientific and Technical Information of China (English)

    贾钟琦

    2015-01-01

    Language learning is a constructive process,in which learners construe the target language based on the acquired rules of grammar and syntax.However,the language that learners produce at early or later stages of the acquisition is different from the standard norms or in other words deviant form the target language from the socio-linguistic,psycho-linguistic and pragmatic points of views.Different learner lead to different learning effects.There are many factors influenced learners.

  18. 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.

  19. 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)

  20. 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.

  1. 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.

  2. Differences in individual susceptibility affect the development of trigeminal neuralgia

    Institute of Scientific and Technical Information of China (English)

    Yusuf Kurtulu(s) Duransoy; Mesut Mete; Emrah Ak(c)ay; Mehmet Sel(c)uki1

    2013-01-01

    Trigeminal neuralgia is a syndrome due to dysfunctional hyperactivity of the trigeminal nerve, and is characterized by a sudden, usually unilateral, recurrent lancinating pain arising from one or more divisions of the nerve. The most accepted pathogenetic mechanism for trigeminal neuralgia is compression of the nerve at its dorsal root entry zone or in its distal course. In this paper, we report four cases with trigeminal neuralgia due to an unknown mechanism after an intracranial intervention. The onset of trigeminal neuralgia after surgical interventions that are unrelated to the trigeminal nerve suggests that in patients with greater individual susceptibility, nerve contact with the vascular structure due to postoperative pressure and changes in cerebrospinal fluid flow may cause the onset of pain.

  3. Individual differences in the acquisition of affectively valenced associations.

    Science.gov (United States)

    Zinbarg, R E; Mohlman, J

    1998-04-01

    Two studies were conducted to test the predictions derived from the behavioral activation system and behavioral inhibition system theory of personality that trait anxiety is positively related to the speed of acquisition of punishment expectancies and impulsivity is positively related to the speed of acquisition of reward expectancies. Both studies used a standard approach-avoidance discrimination task with self-report measures of expectancies. Both studies found support for the hypothesized relation between trait and acquisition of punishment expectancies but not for the hypothesized relation between impulsivity and acquisition of reward expectancies. Study 2 suggested that the relation between trait anxiety and punishment expectancy is affected by the type of incentive and the type of trait anxiety measure used. The results suggest that highly trait anxious individuals are more susceptible to developing new sources of anxiety than others.

  4. 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.

  5. Predicting gender differences as latent variables: summed scores, and individual item responses: a methods case study

    Directory of Open Access Journals (Sweden)

    Jacobs Danny O

    2004-10-01

    Full Text Available Abstract Background Modeling latent variables such as physical disability is challenging since its measurement is performed through proxies. This poses significant methodological challenges. The objective of this article is to present three different methods to predict latent variables based on classical summed scores, individual item responses, and latent variable models. Methods This is a review of the literature and data analysis using "layers of information". Data was collected from the North Carolina Back Pain Project, using a modified version of the Roland Questionnaire. Results The three models are compared in relation to their goals and underlying concepts, previous clinical applications, data requirements, statistical theory, and practical applications. Initial linear regression models demonstrated a difference in disability between genders of 1.32 points (95% CI 0.65, 2.00 on a scale from 0–23. Subsequent item analysis found contradictory results across items, with no clear pattern. Finally, IRT models demonstrated three items were demonstrated to present differential item functioning. After these items were removed, the difference between genders was reduced to 0.78 points (95% CI, -0.99, 1.23. These results were shown to be robust with re-sampling methods. Conclusions Purported differences in the levels of a latent variable should be tested using different models to verify whether these differences are real or simply distorted by model assumptions.

  6. 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.

  7. 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 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.

  8. Metagenomic Sequencing Indicates That the Oropharyngeal Phageome of Individuals With Schizophrenia Differs From That of Controls

    Science.gov (United States)

    Yolken, Robert H.; Severance, Emily G.; Sabunciyan, Sarven; Gressitt, Kristin L.; Chen, Ou; Stallings, Cassie; Origoni, Andrea; Katsafanas, Emily; Schweinfurth, Lucy A. B.; Savage, Christina L. G.; Banis, Maria; Khushalani, Sunil; Dickerson, Faith B.

    2015-01-01

    Mucosal sites such as the oropharynx contain a wide range of microorganisms, collectively designated as the microbiome. The microbiome can affect behavior through a number of neurobiological and immunological mechanisms. Most previous studies have focused on the bacterial components of the microbiome. However, the microbiome also includes viruses such as bacteriophages, which are viruses that infect bacteria and alter their metabolism and replication. We employed metagenomic analysis to characterize bacteriophage genomes in the oral pharynx of 41 individuals with schizophrenia and 33 control individuals without a psychiatric disorder. This analysis was performed by the generation of more than 100000000 sequence reads from each sample and the mapping of these reads to databases. We identified 79 distinct bacteriophage sequences in the oropharyngeal samples. Of these, one bacteriophage genome, Lactobacillus phage phiadh, was found to be significantly different in individuals with schizophrenia (P < .00037, q < 0.03 adjusted for multiple comparisons). The differential levels of Lactobacillus phage phiadh remained significant when controlling for age, gender, race, socioeconomic status, or cigarette smoking (P < .006). Within the group of individuals with schizophrenia, the level of Lactobacillus phage phiadh correlated with the prevalence of immunological disorders as well as with the administration of valproate, which has been shown in animal models to alter the microbiome. The bacteriophage composition of the oropharynx in individuals with schizophrenia differs from that of controls. The biological consequences of this difference and the potential effects of altering bacteriophage levels through therapeutic interventions are worthy of further investigation. PMID:25666826

  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. Individual patient information to select patients for different radiation techniques

    NARCIS (Netherlands)

    Quik, E. H.; Feenstra, T. L.; Postmus, D.; Slotman, B. J.; Leemans, C. R.; Krabbe, P. F. M.; Langendijk, J. A.

    2016-01-01

    Background and purpose: Proton therapy is an emerging technique in radiotherapy which results in less dose to the normal tissues with similar target dose than photon therapy, the current standard. Patient-level simulation models support better decision making on which patients would benefit most. Ma

  11. Priming and Habituation for Faces: Individual Differences and Inversion Effects

    Science.gov (United States)

    Rieth, Cory A.; Huber, David E.

    2010-01-01

    Immediate repetition priming for faces was examined across a range of prime durations in a threshold identification task. Similar to word repetition priming results, short duration face primes produced positive priming whereas long duration face primes eliminated or reversed this effect. A habituation model of such priming effects predicted that…

  12. Predicting Individual Differences in Reading Comprehension: A Twin Study

    Science.gov (United States)

    Harlaar, Nicole; Cutting, Laurie; Deater-Deckard, Kirby; DeThorne, Laura S.; Justice, Laura M.; Schatschneider, Chris; Thompson, Lee A.; Petrill, Stephen A.

    2010-01-01

    We examined the Simple View of reading from a behavioral genetic perspective. Two aspects of word decoding (phonological decoding and word recognition), two aspects of oral language skill (listening comprehension and vocabulary), and reading comprehension were assessed in a twin sample at age 9. Using latent factor models, we found that overlap…

  13. Priming and Habituation for Faces: Individual Differences and Inversion Effects

    Science.gov (United States)

    Rieth, Cory A.; Huber, David E.

    2010-01-01

    Immediate repetition priming for faces was examined across a range of prime durations in a threshold identification task. Similar to word repetition priming results, short duration face primes produced positive priming whereas long duration face primes eliminated or reversed this effect. A habituation model of such priming effects predicted that…

  14. Individual perception of different stimuli: Implications for managers

    Directory of Open Access Journals (Sweden)

    Santos- Álvarez, M.V.

    2012-01-01

    Full Text Available Managerial perception is the process by which managers form an image of the stimuli they receive. According to research, perception is conditioned by the individual’s cognitive profile. But the different nature of incoming stimuli suggests that it would be interesting to study whether the cognitive profile’s influence varies in the presence of different stimuli. This paper analyses the effect of the cognitive profile on perception of differently-structured stimuli. The results clearly show that the cognitive style, tolerance of ambiguity, and proactivity have an effect. Specifically, they condition the recognition of stimuli, particularly when the stimuli are relatively unstructured. The results also show that the cognitive variables have less influence in the interpretation stage.

  15. 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.

  16. 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.

  17. Predicting individual differences in reading comprehension: a twin study

    OpenAIRE

    Harlaar, Nicole; Cutting, Laurie; Deater-Deckard, Kirby; DeThorne, Laura S.; Justice, Laura M.; Schatschneider, Chris; Thompson, Lee A.; Petrill, Stephen A.

    2010-01-01

    We examined the Simple View of reading from a behavioral genetic perspective. Two aspects of word decoding (phonological decoding and word recognition), two aspects of oral language skill (listening comprehension and vocabulary), and reading comprehension were assessed in a twin sample at age 9. Using latent factor models, we found that overlap among phonological decoding, word recognition, listening comprehension, vocabulary, and reading comprehension was primarily due to genetic influences....

  18. Leader Identity, Individual Differences, and Leader Self-Development

    Science.gov (United States)

    2012-09-01

    military participants – results are aggregated across the two groups. Overall model fit. The chi-square test was used to test the meditational effect...J., & Harackiewicz, J. M. (1996). Approach and avoidance achievement goals and intrinsic motivation: A meditational analysis. Journal of...the classroom (e.g., MBA) • Listen to books on tape / CD related to leadership • Participate in additional military courses designed to help

  19. Individual Differences in Reactions to Irregular Work Hours

    Science.gov (United States)

    2000-03-01

    over a temporary 10-week for small children find no differences period of weekly alternation between night (Estryn-Behar et. al., 1978, Beermann, 1995...Eds). Ergonomics, Health andditracsndlepiodrsnshfDre ds). P ergonomies , Healthe aindti. workers. In: P.A. Buser, W.A. Cobb, T. Safety. Perspectives

  20. Trichloroethylene risk assessment: Relevance of inter-individual differences

    NARCIS (Netherlands)

    Vermeulen, N.P.E.; Bladeren, van P.J.

    2001-01-01

    Interindividual variability in the disposition and effects of xenobiotics in humans and related inter-species differences should play a major role in human risk assessment. In particular for low-dose exposures to potentially carcinogenic compounds, novel tools and concepts are necessary to assess

  1. Individual Differences in Substance Preference and Substance Use

    Science.gov (United States)

    Feldman, Marc; Kumar, V. K.; Angelini, Frank; Pekala, Ronald J.; Porter, Jack

    2007-01-01

    Using H. J. Eysenck's (1957,1967) theory of temperament, this study examined the relationship between drug preference, drug use, and personality among incarcerated inmates. Analysis indicated a general preference for marijuana and alcohol over 8 other commonly used drugs across different personality types. Theoretical and clinical implications are…

  2. Assessing Learning from Hypertext: An Individual Differences Perspective

    Science.gov (United States)

    Graff, Martin

    2003-01-01

    From an instructional perspective, it is conceivable that employing an appropriate hypertext architecture should have the advantage of facilitating learning by representing logically the interrelationships between the different pieces of information contained within the hypertext. Furthermore, there would however appear to be a sound theoretical…

  3. 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.

  4. 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.

  5. 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.

  6. 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.

  7. Aspergers – Different, Not Less: Occupational Strengths and Job Interests of Individuals with Asperger's Syndrome

    Science.gov (United States)

    Lorenz, Timo; Heinitz, Kathrin

    2014-01-01

    Rooted in the neurodiversity approach, this study provides an overview of the strengths and interests of individuals with Asperger's Syndrome. We interviewed136 individuals with Asperger's Syndrome and 155 neurotypical individuals via an online survey with regards to (a) demography, (b) occupational strengths, (c) general self-efficacy, (d) occupational self-efficacy, and (e) the job interest profile according to Holland. The vocational and educational fields of the individuals with Asperger's in the sample are more diverse than and surpass those classical fields stated in research and biographical literature. The comparison of both groups in cross-tables showed that the indicated strengths differ in several areas (ΦCramer = .02–.47), which means that a specific strength profile can be derived, and this profile goes beyond the clinical view of the diagnostic criteria. Individuals with Asperger's indicate lower self-efficacy, both general and occupational. Furthermore, a high concentration of individuals with Asperger's can be found in the areas I (Investigative) and C (Conventional) of Holland's RIASEC model. PMID:24950060

  8. Aspergers--different, not less: occupational strengths and job interests of individuals with Asperger's Syndrome.

    Directory of Open Access Journals (Sweden)

    Timo Lorenz

    Full Text Available Rooted in the neurodiversity approach, this study provides an overview of the strengths and interests of individuals with Asperger's Syndrome. We interviewed 136 individuals with Asperger's Syndrome and 155 neurotypical individuals via an online survey with regards to (a demography, (b occupational strengths, (c general self-efficacy, (d occupational self-efficacy, and (e the job interest profile according to Holland. The vocational and educational fields of the individuals with Asperger's in the sample are more diverse than and surpass those classical fields stated in research and biographical literature. The comparison of both groups in cross-tables showed that the indicated strengths differ in several areas (ΦCramer = .02-.47, which means that a specific strength profile can be derived, and this profile goes beyond the clinical view of the diagnostic criteria. Individuals with Asperger's indicate lower self-efficacy, both general and occupational. Furthermore, a high concentration of individuals with Asperger's can be found in the areas I (Investigative and C (Conventional of Holland's RIASEC model.

  9. Aspergers--different, not less: occupational strengths and job interests of individuals with Asperger's Syndrome.

    Science.gov (United States)

    Lorenz, Timo; Heinitz, Kathrin

    2014-01-01

    Rooted in the neurodiversity approach, this study provides an overview of the strengths and interests of individuals with Asperger's Syndrome. We interviewed 136 individuals with Asperger's Syndrome and 155 neurotypical individuals via an online survey with regards to (a) demography, (b) occupational strengths, (c) general self-efficacy, (d) occupational self-efficacy, and (e) the job interest profile according to Holland. The vocational and educational fields of the individuals with Asperger's in the sample are more diverse than and surpass those classical fields stated in research and biographical literature. The comparison of both groups in cross-tables showed that the indicated strengths differ in several areas (ΦCramer = .02-.47), which means that a specific strength profile can be derived, and this profile goes beyond the clinical view of the diagnostic criteria. Individuals with Asperger's indicate lower self-efficacy, both general and occupational. Furthermore, a high concentration of individuals with Asperger's can be found in the areas I (Investigative) and C (Conventional) of Holland's RIASEC model.

  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. Genetic Influences on Individual Differences in Exercise Behavior during Adolescence

    Directory of Open Access Journals (Sweden)

    Niels van der Aa

    2010-01-01

    Full Text Available The aim of this study was to investigate the degree to which genetic and environmental influences affect variation in adolescent exercise behavior. Data on regular leisure time exercise activities were analyzed in 8,355 adolescent twins, from three-age cohorts (13-14, 15-16, and 17–19 years. Exercise behavior was assessed with survey items about type of regular leisure time exercise, frequency, and duration of the activities. Participants were classified as sedentary, regular exercisers, or vigorous exercisers. The prevalence of moderate exercise behavior declined from age 13 to 19 years with a parallel increase in prevalence of sedentary behavior, whereas the prevalence of vigorous exercise behavior remained constant across age cohorts. Variation in exercise behavior was analyzed with genetic structural equation modeling employing a liability threshold model. Variation was largely accounted for by genetic factors (72% to 85% of the variance was explained by genetic factors, whereas shared environmental factors only accounted for a substantial part of the variation in girls aged 13-14 years (46%. We hypothesize that genetic effects on exercise ability may explain the high heritability of exercise behavior in this phase of life.

  12. 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.

  13. 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

  14. A paradox in individual-based models of populations

    NARCIS (Netherlands)

    Van der Meer, J.

    2016-01-01

    The standard dynamic energy budget model is widely used to describe the physiology of individual animals. It assumes thatassimilation rate scales with body surface area, whereas maintenance rate scales with body volume. When the model is usedas the building block of a population model, only limited

  15. Predicting individual differences in reading comprehension: a twin study

    Science.gov (United States)

    Cutting, Laurie; Deater-Deckard, Kirby; DeThorne, Laura S.; Justice, Laura M.; Schatschneider, Chris; Thompson, Lee A.; Petrill, Stephen A.

    2010-01-01

    We examined the Simple View of reading from a behavioral genetic perspective. Two aspects of word decoding (phonological decoding and word recognition), two aspects of oral language skill (listening comprehension and vocabulary), and reading comprehension were assessed in a twin sample at age 9. Using latent factor models, we found that overlap among phonological decoding, word recognition, listening comprehension, vocabulary, and reading comprehension was primarily due to genetic influences. Shared environmental influences accounted for associations among word recognition, listening comprehension, vocabulary, and reading comprehension. Independent of phonological decoding and word recognition, there was a separate genetic link between listening comprehension, vocabulary, and reading comprehension and a specific shared environmental link between vocabulary and reading comprehension. There were no residual genetic or environmental influences on reading comprehension. The findings provide evidence for a genetic basis to the “Simple View” of reading. PMID:20814768

  16. Predicting individual differences in reading comprehension: a twin study.

    Science.gov (United States)

    Harlaar, Nicole; Cutting, Laurie; Deater-Deckard, Kirby; Dethorne, Laura S; Justice, Laura M; Schatschneider, Chris; Thompson, Lee A; Petrill, Stephen A

    2010-12-01

    We examined the Simple View of reading from a behavioral genetic perspective. Two aspects of word decoding (phonological decoding and word recognition), two aspects of oral language skill (listening comprehension and vocabulary), and reading comprehension were assessed in a twin sample at age 9. Using latent factor models, we found that overlap among phonological decoding, word recognition, listening comprehension, vocabulary, and reading comprehension was primarily due to genetic influences. Shared environmental influences accounted for associations among word recognition, listening comprehension, vocabulary, and reading comprehension. Independent of phonological decoding and word recognition, there was a separate genetic link between listening comprehension, vocabulary, and reading comprehension and a specific shared environmental link between vocabulary and reading comprehension. There were no residual genetic or environmental influences on reading comprehension. The findings provide evidence for a genetic basis to the "Simple View" of reading.

  17. Maximum likelihood estimators for extended growth curve model with orthogonal between-individual design matrices

    NARCIS (Netherlands)

    Klein, Daniel; Zezula, Ivan

    The extended growth curve model is discussed in this paper. There are two versions of the model studied in the literature, which differ in the way how the column spaces of the design matrices are nested. The nesting is applied either to the between-individual or to the within-individual design

  18. Individualized music--a different approach to the restraint issue.

    Science.gov (United States)

    Janelli, Linda M; Kanski, Genevieve W; Wu, Yow-Wu Bill

    2002-01-01

    Rehabilitation nurses who work with geriatric patients are concerned about reliance on physical restraints, as are all nurses. Controversy exists as to the benefits and risks, as well as the ethical and legal consequences, of their use. Nurses are ambivalent about using restraints, believing that they affect patients' freedom, self-respect, and self-reliance; they also often believe that there are no appropriate alternatives. This pilot study explored the use of music as a potential alternative to using physical restraints with hospitalized patients. The research question was: Will patients have more positive behaviors, as measured by the Restraint Music Response Instrument (RMRI), while out of restraints and listening to preferred music compared with the patients not listening to music who are out of restraints while being observed? Forty medical-surgical patients participated in the study and were randomized into either the experimental group (music) or the control group (no music). The mean age of the 21 males and 19 females was 76.6 years (range 56-94). A t test for equality of means was used to determine if there were differences in the number of positive and negative behaviors in the preintervention, intervention, and postintervention phases between the two groups. There was a significant difference (p < .01) in behaviors during the intervention phase. Patients who listened to preferred music had more positive behaviors while out of restraints than patients who were out of restraints but not exposed to music.

  19. Salivary Concentration of Progesterone and Cortisol Significantly Differs Across Individuals After Correcting for Blood Hormone Values

    Science.gov (United States)

    Konishi, Shoko; Brindle, Eleanor; Guyton, Amanda; O’Connor, Kathleen A.

    2014-01-01

    Between-individual variation of salivary progesterone (P4) and cortisol levels does not always closely reflect blood hormone concentrations. This may be partly a function of individual differences in salivary hormone excretion. We tested whether time of day at sampling and ethnicity contributed to individual variation in salivary hormones after adjusting for blood hormone levels. Forty-three Caucasian and 15 Japanese women (18–34 years) collected four sets of matched dried blood spot (DBS) and saliva specimens across a menstrual cycle (N = 232 specimen sets). Linear fixed-effects (LFE) models were used to estimate the effects of diurnal variation and ethnicity on salivary P4 and cortisol while adjusting for DBS levels. For each hormone, women with exclusively positive or negative residuals (unexplained variance) from the LFE models were categorized as high- or low-saliva-to-DBS hormone ratio (SDR; high or low salivary secretors), respectively. We found that salivary P4 (P < 0.05) was significantly higher in early morning compared to the afternoon, after controlling for DBS levels, ethnicity, and BMI. After further adjusting for this diurnal effect, significant individual variation in salivary P4 and cortisol remained: sixteen and nine women, respectively were categorized as low or high salivary secretors for both hormones (P < 0.001), suggesting systematic individual-specific variation of salivary hormonal concentration. We conclude that when saliva is used to quantify P4 or cortisol levels, time of day at sampling should be controlled. Even with this adjustment, salivary P4 and cortisol do not closely mirror between-individual variation of serum P4 and cortisol in a substantial proportion of individuals. PMID:22826025

  20. 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.

  1. Individual differences in local gray matter density are associated with differences in affective and cognitive empathy.

    Science.gov (United States)

    Eres, Robert; Decety, Jean; Louis, Winnifred R; Molenberghs, Pascal

    2015-08-15

    The understanding of empathy from a neuroscientific perspective has recently developed quickly, with numerous functional MRI studies associating different brain regions with different components of empathy. A recent meta-analysis across 40 fMRI studies revealed that affective empathy is most often associated with increased activity in the insula, whereas cognitive empathy is most often associated with activity in the midcingulate cortex and adjacent dorsomedial prefrontal cortex (MCC/dmPFC). To date, however, it remains unclear whether individual differences in brain morphometry in these regions underlie different dispositions in affective and cognitive empathy. In order to test this hypothesis, voxel-based morphometry (VBM) was used to examine the extent to which gray matter density predicts scores from an established empathy measure (Questionnaire of Cognitive and Affective Empathy; QCAE). One hundred and seventy-six participants completed the QCAE and underwent MRI in order to acquire a high-resolution, three-dimensional T1-weighted structural scans. A factor analysis of the questionnaire scores revealed two distinct factors of empathy, affective and cognitive, which confirmed the validity of the QCAE. VBM results revealed gray matter density differences associated with the distinct components of empathy. Higher scores on affective empathy were associated with greater gray matter density in the insula cortex and higher scores of cognitive empathy were associated with greater gray matter density in the MCC/dmPFC. Taken together, these results provide validation for empathy being a multi-component construct, suggesting that affective and cognitive empathy are differentially represented in brain morphometry as well as providing convergent evidence for empathy being represented by different neural and structural correlates. Copyright © 2015 Elsevier Inc. All rights reserved.

  2. 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.

  3. Mind the gap: glucocorticoids modulate hippocampal glutamate tone underlying individual differences in stress susceptibility.

    Science.gov (United States)

    Nasca, C; Bigio, B; Zelli, D; Nicoletti, F; McEwen, B S

    2015-06-01

    Why do some individuals succumb to stress and develop debilitating psychiatric disorders, whereas others adapt well in the face of adversity? There is a gap in understanding the neural bases of individual differences in the responses to environmental factors on brain development and functions. Here, using a novel approach for screening an inbred population of laboratory animals, we identified two subpopulations of mice: susceptible mice that show mood-related abnormalities compared with resilient mice, which cope better with stress. This approach combined with molecular and behavioral analyses, led us to recognize, in hippocampus, presynaptic mGlu2 receptors, which inhibit glutamate release, as a stress-sensitive marker of individual differences to stress-induced mood disorders. Indeed, genetic mGlu2 deletion in mice results in a more severe susceptibility to stress, mimicking the susceptible mouse sub-population. Furthermore, we describe an underlying mechanism by which glucocorticoids, acting via mineralocorticoid receptors (MRs), decrease resilience to stress via downregulation of mGlu2 receptors. We also provide a mechanistic link between MRs and an epigenetic control of the glutamatergic synapse that underlies susceptibility to stressful experiences. The approach and the epigenetic allostasis concept introduced here serve as a model for identifying individual differences based upon biomarkers and underlying mechanisms and also provide molecular features that may be useful in translation to human behavior and psychopathology.

  4. 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.

  5. Water footprint of individuals with different diet patterns

    Directory of Open Access Journals (Sweden)

    João Hugo Baracuy da Cunha Campos

    2013-04-01

    Full Text Available The “water footprint” (WF concept has been recently introduced as an important indicator of human water consumption. WF is defined as the total volume of water used during the production and consumption of goods and services as well as of direct water consumption by humans. The objective of this work was to use the WF concept to analyze vegetarian and non-vegetarian consumers with different levels of family income. A case study was conducted with residents of Caicó city (Brazil in order to estimate total amount of water consumed or polluted while producing the goods and services utilized by these consumers. The results indicated that, on average, the WF of the vegetarian consumer represents 58% of non- vegetarian consumers. The WF of the non-vegetarian female consumer was 10-13% smaller than that of the male consumer while for vegetarian consumers the female’s WF was only 5.8% less than the male’s. The WF of the consumer increases linearly with the family income. A population’s water footprint increases as a function of family income and decreases according to eating habits.

  6. The Big Picture of Individual Differences in Physical Activity Behavior Change: A Transdisciplinary Approach.

    Science.gov (United States)

    Bryan, Angela D; Nilsson, Renea; Tompkins, Sara Anne; Magnan, Renee E; Marcus, Bess H; Hutchison, Kent E

    2011-01-01

    The goal of this research is to utilize a transdisciplinary framework to guide the selection of putative moderators of the effectiveness of an intervention to promote physical activity behavior adoption and maintenance in the context of a randomized controlled intervention trial. Effective interventions to increase physical activity are sorely needed, and one barrier to the identification and development of such interventions is the lack of research targeted at understanding both the mechanisms of intervention efficacy and for whom particular interventions are effective. The purpose of this paper is to outline our transdisciplinary approach to understanding individual differences in the effectiveness of a previously successful exercise promotion intervention. We explain the rationale for and operationalization of our framework, characteristics of the study to which we apply the framework, and planned analyses. By embracing a transdisciplinary orientation for individual differences important in the prediction of physical activity (spanning molecular approaches, animal models, human laboratory models, and social psychological models), we hope to have a better understanding of characteristics of individuals that are important in the adoption and maintenance of physical activity.

  7. Neural correlates of individual performance differences in resolving perceptual conflict.

    Directory of Open Access Journals (Sweden)

    Franziska Labrenz

    Full Text Available Attentional mechanisms are a crucial prerequisite to organize behavior. Most situations may be characterized by a 'competition' between salient, but irrelevant stimuli and less salient, relevant stimuli. In such situations top-down and bottom-up mechanisms interact with each other. In the present fMRI study, we examined how interindividual differences in resolving situations of perceptual conflict are reflected in brain networks mediating attentional selection. Doing so, we employed a change detection task in which subjects had to detect luminance changes in the presence and absence of competing distractors. The results show that good performers presented increased activation in the orbitofrontal cortex (BA 11, anterior cingulate (BA 25, inferior parietal lobule (BA 40 and visual areas V2 and V3 but decreased activation in BA 39. This suggests that areas mediating top-down attentional control are stronger activated in this group. Increased activity in visual areas reflects distinct neuronal enhancement relating to selective attentional mechanisms in order to solve the perceptual conflict. Opposed to good performers, brain areas activated by poor performers comprised the left inferior parietal lobule (BA 39 and fronto-parietal and visual regions were continuously deactivated, suggesting that poor performers perceive stronger conflict than good performers. Moreover, the suppression of neural activation in visual areas might indicate a strategy of poor performers to inhibit the processing of the irrelevant non-target feature. These results indicate that high sensitivity in perceptual areas and increased attentional control led to less conflict in stimulus processing and consequently to higher performance in competitive attentional selection.

  8. Neural correlates of individual performance differences in resolving perceptual conflict.

    Science.gov (United States)

    Labrenz, Franziska; Themann, Maria; Wascher, Edmund; Beste, Christian; Pfleiderer, Bettina

    2012-01-01

    Attentional mechanisms are a crucial prerequisite to organize behavior. Most situations may be characterized by a 'competition' between salient, but irrelevant stimuli and less salient, relevant stimuli. In such situations top-down and bottom-up mechanisms interact with each other. In the present fMRI study, we examined how interindividual differences in resolving situations of perceptual conflict are reflected in brain networks mediating attentional selection. Doing so, we employed a change detection task in which subjects had to detect luminance changes in the presence and absence of competing distractors. The results show that good performers presented increased activation in the orbitofrontal cortex (BA 11), anterior cingulate (BA 25), inferior parietal lobule (BA 40) and visual areas V2 and V3 but decreased activation in BA 39. This suggests that areas mediating top-down attentional control are stronger activated in this group. Increased activity in visual areas reflects distinct neuronal enhancement relating to selective attentional mechanisms in order to solve the perceptual conflict. Opposed to good performers, brain areas activated by poor performers comprised the left inferior parietal lobule (BA 39) and fronto-parietal and visual regions were continuously deactivated, suggesting that poor performers perceive stronger conflict than good performers. Moreover, the suppression of neural activation in visual areas might indicate a strategy of poor performers to inhibit the processing of the irrelevant non-target feature. These results indicate that high sensitivity in perceptual areas and increased attentional control led to less conflict in stimulus processing and consequently to higher performance in competitive attentional selection.

  9. Inter- and intra-individual differences in teachers' self-efficacy: A multilevel factor exploration.

    Science.gov (United States)

    Zee, Marjolein; Koomen, Helma M Y; Jellesma, Francine C; Geerlings, Jolien; de Jong, Peter F

    2016-04-01

    This study explored inter- and intra-individual differences in teachers' self-efficacy (TSE) by adapting Tschannen-Moran and Woolfolk Hoy's (2001) Teachers' Sense of Efficacy Scale (TSES) to the domain- and student-specific level. Multilevel structural equation modeling was used to evaluate the factor structure underlying this adapted instrument, and to test for violations of measurement invariance over clusters. Results from 841 third- to sixth-grade students and their 107 teachers supported the existence of one higher-order factor (Overall TSE) and four lower-order factors (Instructional Strategies, Behavior Management, Student Engagement, and Emotional Support) at both the between- and within-teacher level. In this factor model, intra-individual differences in TSE were generally larger than inter-individual differences. Additionally, the presence of cluster bias in 18 of 24 items suggested that the unique domains of student-specific TSE at the between-teacher level cannot merely be perceived as the within-teacher level factors' aggregates. These findings underscore the importance of further investigating TSE in relation to teacher, student, and classroom characteristics.

  10. Examining differences in developmental work personality across disability category: Implications for individuals with psychiatric disabilities.

    Science.gov (United States)

    O'Sullivan, Deirdre; Strauser, David R; Wong, Alex W K

    2012-01-01

    The purpose of this exploratory study was to examine the differences in levels of work personality for persons with psychiatric disabilities compared to persons with other types of disabilities. Seventy one adults eligible to receive Vocational Rehabilitation services participated; 30 reported a physical disability, 26 reported a psychiatric disability, and 15 reported a learning disability. Eligible participants were recruited through VR offices and volunteered to participate. Results indicate that persons with psychiatric disabilities scored significantly lower on the Work Task and Social Skills subscales of the Developmental Work Personality Scale (DWPS) when compared to individuals with physical disabilities, but scored higher than individuals with physical and learning disabilities on the Role Model subscale. The results of this study provide some initial clarity regarding developmental work personality differences among three broad categories of disability. Recommendations for future research are provided.

  11. 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.

  12. Markovian Building Blocks for Individual-Based Modelling

    OpenAIRE

    Nilsson, Lars Anders Fredrik; Nielsen, Bo Friis; Thygesen, Uffe Høgsbro; Beyer, Jan

    2007-01-01

    The present thesis consists of a summary report, four research articles, one technical report and one manuscript. The subject of the thesis is individual-based stochastic models. The summary report is composed of three parts and a brief history of some basic models in population biology. This history is included in order to provide a reader that has no previous exposure to models in population biology with a sufficient background to understand some of the biological models that are mentioned ...

  13. 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.

  14. Cognitive Modeling of Individual Variation in Reference Production and Comprehension.

    Science.gov (United States)

    Hendriks, Petra

    2016-01-01

    A challenge for most theoretical and computational accounts of linguistic reference is the observation that language users vary considerably in their referential choices. Part of the variation observed among and within language users and across tasks may be explained from variation in the cognitive resources available to speakers and listeners. This paper presents a computational model of reference production and comprehension developed within the cognitive architecture ACT-R. Through simulations with this ACT-R model, it is investigated how cognitive constraints interact with linguistic constraints and features of the linguistic discourse in speakers' production and listeners' comprehension of referring expressions in specific tasks, and how this interaction may give rise to variation in referential choice. The ACT-R model of reference explains and predicts variation among language users in their referential choices as a result of individual and task-related differences in processing speed and working memory capacity. Because of limitations in their cognitive capacities, speakers sometimes underspecify or overspecify their referring expressions, and listeners sometimes choose incorrect referents or are overly liberal in their interpretation of referring expressions.

  15. Cognitive Modeling of Individual Variation in Reference Production and Comprehension

    Directory of Open Access Journals (Sweden)

    Petra eHendriks

    2016-04-01

    Full Text Available A challenge for most theoretical and computational accounts of linguistic reference is the observation that language users vary considerably in their referential choices. Part of the variation observed among and within language users and across tasks may be explained from variation in the cognitive resources available to speakers and listeners. This paper presents a computational model of reference production and comprehension developed within the cognitive architecture ACT-R. Through simulations with this ACT-R model, it is investigated how cognitive constraints interact with linguistic constraints and features of the linguistic discourse in speakers’ production and listeners’ comprehension of referring expressions in specific tasks, and how this interaction may give rise to variation in referential choice. The ACT-R model of reference explains and predicts variation among language users in their referential choices as a result of individual and task-related differences in processing speed and working memory capacity. Because of limitations in their cognitive capacities, speakers sometimes underspecify or overspecify their referring expressions, and listeners sometimes choose incorrect referents or are overly liberal in their interpretation of referring expressions.

  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. Hearing dummies: individualized computer models of hearing impairment.

    Science.gov (United States)

    Panda, Manasa R; Lecluyse, Wendy; Tan, Christine M; Jürgens, Tim; Meddis, Ray

    2014-10-01

    Objective: Our aim was to explore the usage of individualized computer models to simulate hearing loss based on detailed psychophysical assessment and to offer hypothetical diagnoses of the underlying pathology. Individualized computer models of normal and impaired hearing were constructed and evaluated using the psychophysical data obtained from human listeners. Computer models of impaired hearing were generated to reflect the hypothesized underlying pathology (e.g. dead regions, outer hair cell dysfunction, or reductions in endocochlear potential). These models were evaluated in terms of their ability to replicate the original patient data. Auditory profiles were measured for two normal and five hearing-impaired listeners using a battery of three psychophysical tests (absolute thresholds, frequency selectivity, and compression). The individualized computer models were found to match the data. Useful fits to the impaired profiles could be obtained by changing only a single parameter in the model of normal hearing. Sometimes, however, it was necessary to include an additional dead region. The creation of individualized computer models of hearing loss can be used to simulate auditory profiles of impaired listeners and suggest hypotheses concerning the underlying peripheral pathology.

  18. Individual thorax geometry reduces position and size differences in reconstructed images of electrical impedance tomography.

    Science.gov (United States)

    Zhao, Zhanqi; Frerichs, Inéz; Pulletz, Sven; Müller-Lisse, Ullrich; Möller, Knut

    2014-01-01

    Due to the ill-posed problem, the electrical impedance within the thorax cannot be exactly reconstructed. The aim of our study was to prove that reconstruction with individual thorax geometry improved the quality of EIT (electrical impedance tomography) images. Seven mechanically ventilated patients with acute respiratory distress syndrome were examined by EIT. The thorax contours were determined from routine computed tomography (CT) images based on automatic threshold filtering. EIT raw data was reconstructed offline with (1) back-projection with circular forward model; (2) GREIT reconstruction method with circular forward model and (3) GREIT with individual thorax geometry. The resulting EIT images were compared to rescaled CT images. The distance between the lung contour and the thorax contour was calculated for each method and the differences to that in CT were denoted as position differences. Shape differences was defined as the ratio of thorax (or lungs) size in EIT and that in rescaled CT. Method (3) has the smallest position differences (6.6 ± 2.8, 5.3 ± 3.3, 2.3 ± 1.4 in pixel, for each reconstruction method respectively; mean ± SD). The thorax and lungs sizes in the transformed CT images were 514 ± 73 and 177 ± 39. Shape differences of thorax were 1.81 ± 0.26, 1.81 ± 0.26, 1.10 ± 0.12 and that of lungs were 1.69 ± 0.45, 1.52 ± 0.45, 1.34 ± 0.35 for each method respectively. The reconstructed images using the GREIT method with individual thorax geometry were more realistic. Improvement of EIT image quality may foster the acceptance of EIT in routine clinical use.

  19. The attachment system and physiology in adulthood: normative processes, individual differences, and implications for health.

    Science.gov (United States)

    Robles, Theodore F; Kane, Heidi S

    2014-12-01

    Attachment theory provides a conceptual framework for understanding intersections between personality and close relationships in adulthood. Moreover, attachment has implications for stress-related physiology and physical health. We review work on normative processes and individual differences in the attachment behavioral system, as well as their associations with biological mechanisms related to health outcomes. We highlight the need for more basic research on normative processes and physiology and discuss our own research on individual differences in attachment and links with physiology. We then describe a novel perspective on attachment and physiology, wherein stress-related physiological changes may also be viewed as supporting the social-cognitive and emotion regulatory functions of the attachment system through providing additional energy to the brain, which has implications for eating behavior and health. We close by discussing our work on individual differences in attachment and restorative processes, including sleep and skin repair, and by stressing the importance of developing biologically plausible models for describing how attachment may impact chronic illness.

  20. A network of amygdala connections predict individual differences in trait anxiety.

    Science.gov (United States)

    Greening, Steven G; Mitchell, Derek G V

    2015-12-01

    In this study we demonstrate that the pattern of an amygdala-centric network contributes to individual differences in trait anxiety. Individual differences in trait anxiety were predicted using maximum likelihood estimates of amygdala structural connectivity to multiple brain targets derived from diffusion-tensor imaging (DTI) and probabilistic tractography on 72 participants. The prediction was performed using a stratified sixfold cross validation procedure using a regularized least square regression model. The analysis revealed a reliable network of regions predicting individual differences in trait anxiety. Higher trait anxiety was associated with stronger connections between the amygdala and dorsal anterior cingulate cortex, an area implicated in the generation of emotional reactions, and inferior temporal gyrus and paracentral lobule, areas associated with perceptual and sensory processing. In contrast, higher trait anxiety was associated with weaker connections between amygdala and regions implicated in extinction learning such as medial orbitofrontal cortex, and memory encoding and environmental context recognition, including posterior cingulate cortex and parahippocampal gyrus. Thus, trait anxiety is not only associated with reduced amygdala connectivity with prefrontal areas associated with emotion modulation, but also enhanced connectivity with sensory areas. This work provides novel anatomical insight into potential mechanisms behind information processing biases observed in disorders of emotion.

  1. 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.

  2. 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.

  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. Improved system identification using artificial neural networks and analysis of individual differences in responses of an identified neuron.

    Science.gov (United States)

    Costalago Meruelo, Alicia; Simpson, David M; Veres, Sandor M; Newland, Philip L

    2016-03-01

    Mathematical modelling is used routinely to understand the coding properties and dynamics of responses of neurons and neural networks. Here we analyse the effectiveness of Artificial Neural Networks (ANNs) as a modelling tool for motor neuron responses. We used ANNs to model the synaptic responses of an identified motor neuron, the fast extensor motor neuron, of the desert locust in response to displacement of a sensory organ, the femoral chordotonal organ, which monitors movements of the tibia relative to the femur of the leg. The aim of the study was threefold: first to determine the potential value of ANNs as tools to model and investigate neural networks, second to understand the generalisation properties of ANNs across individuals and to different input signals and third, to understand individual differences in responses of an identified neuron. A metaheuristic algorithm was developed to design the ANN architectures. The performance of the models generated by the ANNs was compared with those generated through previous mathematical models of the same neuron. The results suggest that ANNs are significantly better than LNL and Wiener models in predicting specific neural responses to Gaussian White Noise, but not significantly different when tested with sinusoidal inputs. They are also able to predict responses of the same neuron in different individuals irrespective of which animal was used to develop the model, although notable differences between some individuals were evident.

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

    Science.gov (United States)

    Lechuga, Julia; Fernandez, Norma P.

    2011-01-01

    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. PMID:21625350

  6. 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.

  7. Task-free MRI predicts individual differences in brain activity during task performance

    NARCIS (Netherlands)

    Tavor, I.; Jones, O.P.; Mars, R.B.; Smith, S.M.; Behrens, T.E.J.; Jbabdi, S.

    2016-01-01

    When asked to perform the same task, different individuals exhibit markedly different patterns of brain activity. This variability is often attributed to volatile factors, such as task strategy or compliance. We propose that individual differences in brain responses are, to a large degree, inherent

  8. In Others' Shoes: Do Individual Differences in Empathy and Theory of Mind Shape Social Preferences?

    OpenAIRE

    Florian Artinger; Filippos Exadaktylos; Hannes Koppel; Lauri Sääksvuori

    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 d...

  9. The true-change model with individual method effects : Reliability issues

    NARCIS (Netherlands)

    Vautier, Stephane; Steyer, Rolf; Boomsma, Anne

    2008-01-01

    The true intra-individual change model is generalized by defining individual method effects. This allows the analysis of non-congeneric test-retest variables assumed to measure a common, possibly (temporally) transient, attribute. Temporal change in the attribute between different times of measureme

  10. Visual working memory capacity: from psychophysics and neurobiology to individual differences.

    Science.gov (United States)

    Luck, Steven J; Vogel, Edward K

    2013-08-01

    Visual working memory capacity is of great interest because it is strongly correlated with overall cognitive ability, can be understood at the level of neural circuits, and is easily measured. Recent studies have shown that capacity influences tasks ranging from saccade targeting to analogical reasoning. A debate has arisen over whether capacity is constrained by a limited number of discrete representations or by an infinitely divisible resource, but the empirical evidence and neural network models currently favor a discrete item limit. Capacity differs markedly across individuals and groups, and recent research indicates that some of these differences reflect true differences in storage capacity whereas others reflect variations in the ability to use memory capacity efficiently. Copyright © 2013 Elsevier Ltd. All rights reserved.

  11. Motivation and strategy use in science: Individual differences and classroom effects

    Science.gov (United States)

    Anderman, Eric M.; Young, Allison J.

    This study examines individual and classroom-level differences in motivation and strategy usage in sixth- and seventh-grade middle school science. Results suggest that students who experience academic difficulties differ from both high achieving and special education students on measures of self-efficacy, goal orientation, expectancy, value, and self-concept of ability in science, with students who experience academic difficulties occasionally demonstrating less adaptive patterns of motivation and cognition than special education students in science. We used hierarchical linear modeling to examine between-classroom differences in learning-focused goal orientation. Findings indicate that students who have science teachers that use ability-focused instructional practices (e.g., pointing out the best students as an example to others) are less learning focused, and exhibit a diminished relation between self-concept of ability and being learning focused in science. Implications for science education reform are discussed.Received: 13 September 1993; Revised: 28 March 1994;

  12. An Improved Methodology for Individualized Performance Prediction of Sleep-Deprived Individuals with the Two-Process Model

    Science.gov (United States)

    2009-01-01

    process model of sleep regulation for developing individualized biomathematical models that predict performance impairment for individuals subjected to total sleep loss. This new method advances our previous work in two important ways. First, it enables model customization to start as soon as the first performance measurement from an individual becomes available. This was achieved by optimally combining the performance information obtained from the individual’s performance measurements with a priori performance information using a Bayesian framework, while retaining

  13. 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.

  14. 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.

  15. Individual Differences in Male Rats in a Behavioral Test Battery: A Multivariate Statistical Approach

    Science.gov (United States)

    Feyissa, Daniel D.; Aher, Yogesh D.; Engidawork, Ephrem; Höger, Harald; Lubec, Gert; Korz, Volker

    2017-01-01

    Animal models for anxiety, depressive-like and cognitive diseases or aging often involve testing of subjects in behavioral test batteries. The large number of test variables with different mean variations and within and between test correlations often constitute a significant problem in determining essential variables to assess behavioral patterns and their variation in individual animals as well as appropriate statistical treatment. Therefore, we applied a multivariate approach (principal component analysis) to analyse the behavioral data of 162 male adult Sprague-Dawley rats that underwent a behavioral test battery including commonly used tests for spatial learning and memory (holeboard) and different behavioral patterns (open field, elevated plus maze, forced swim test) as well as for motor abilities (Rota rod). The high dimensional behavioral results were reduced to fewer components associated with spatial cognition, general activity, anxiety-, and depression-like behavior and motor ability. The loading scores of individual rats on these different components allow an assessment and the distribution of individual features in a population of animals. The reduced number of components can be used also for statistical calculations like appropriate sample sizes for valid discriminations between experimental groups, which otherwise have to be done on each variable. Because the animals were intact, untreated and experimentally naïve the results reflect trait patterns of behavior and thus individuality. The distribution of animals with high or low levels of anxiety, depressive-like behavior, general activity and cognitive features in a local population provides information of the probability of their appeareance in experimental samples and thus may help to avoid biases. However, such an analysis initially requires a large cohort of animals in order to gain a valid assessment.

  16. 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…

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

    NARCIS (Netherlands)

    Duijster, D.; van Loveren, C.; 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) sco

  18. An individuality model for online signatures using global Fourier descriptors

    Science.gov (United States)

    Kholmatov, Alisher; Yanikoglu, Berrin

    2008-03-01

    The discriminative capability of a biometric is based on its individuality/uniqueness and is an important factor in choosing a biometric for a large-scale deployment. Individuality studies have been carried out rigorously for only certain biometrics, in particular fingerprint and iris, while work on establishing handwriting and signature individuality has been mainly on feature level. In this study, we present a preliminary individuality model for online signatures using the Fourier domain representation of the signature. Using the normalized Fourier coefficients as global features describing the signature, we derive a formula for the probability of coincidentally matching a given signature. Estimating model parameters from a large database and making certain simplifying assumptions, the probability of two arbitrary signatures to match in 13 of the coefficients is calculated as 4.7x10 -4. When compared with the results of a verification algorithm that parallels the theoretical model, the results show that the theoretical model fits the random forgery test results fairly well. While online signatures are sometimes dismissed as not very secure, our results show that the probability of successfully guessing an online signature is very low. Combined with the fact that signature is a behavioral biometric with adjustable complexity, these results support the use of online signatures for biometric authentication.

  19. Knowledge Growth: Applied Models of General and Individual Knowledge Evolution

    Science.gov (United States)

    Silkina, Galina Iu.; Bakanova, Svetlana A.

    2016-01-01

    The article considers the mathematical models of the growth and accumulation of scientific and applied knowledge since it is seen as the main potential and key competence of modern companies. The problem is examined on two levels--the growth and evolution of objective knowledge and knowledge evolution of a particular individual. Both processes are…

  20. 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)

  1. Time to see the bigger picture: Individual differences in the attentional blink

    OpenAIRE

    Willems, Charlotte; Martens, Sander

    2015-01-01

    If two to-be-identified targets are presented in close temporal succession, identification for the second target is typically impaired. This attentional blink (AB) phenomenon has long been considered as a robust, universal cognitive limitation. However, more recent studies have demonstrated that AB task performance greatly differs between individuals, with some individuals even showing no AB in certain paradigms. Several studies have focused on these individual differences in an attempt to re...

  2. 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.

  3. 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.

  4. Differences in motor variability among individuals performing a standardized short-cycle manual task.

    Science.gov (United States)

    Sandlund, Jonas; Srinivasan, Divya; Heiden, Marina; Mathiassen, Svend Erik

    2017-01-01

    Motor variability (MV) has been suggested to be a determinant of the risk for developing musculoskeletal disorders in repetitive work. In this study we examined whether individuals consistently differed in the extent of motor variability when performing a standardized short-cycle manual task. On three separate days, arm kinematics was recorded in 14 healthy subjects performing a pipetting task, transferring liquid from a pick-up tube to eight target tubes with a cycle time of 2.8s. Cycle-to-cycle standard deviations (SD) of a large selection of shoulder and elbow kinematic variables, were processed using principal component analysis (PCA). Thereafter, between-subjects and between-days (within-subject) variance components were calculated using a random effects model for each of four extracted principal components. The results showed that MV differed consistently between subjects (95% confidence intervals of the between-subjects variances did not include zero) and that subjects differed consistently in MV between days. Thus, our results support the notion that MV may be a consistent personal trait, even though further research is needed to verify whether individuals rank consistently in MV even across tasks. If so, MV may be a candidate determinant of the risk of developing fatigue and musculoskeletal disorders in repetitive occupational work.

  5. 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 a

  6. 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 relati

  7. Individual differences in reactions towards color in simulated healthcare environments : The role of stimulus screening ability

    NARCIS (Netherlands)

    Dijkstra, K.; Pieterse, Marcel E.; Pruyn, Adriaan T.H.

    2008-01-01

    The notion that the physical healthcare environment can affect our mood and behavior is well established. Despite this, individual differences in sensitivity to environmental stimuli have not received much attention. With the current research showing the importance of individual differences in

  8. Individual Differences in Base Rate Neglect: A Fuzzy Processing Preference Index

    Science.gov (United States)

    Wolfe, Christopher R.; Fisher, Christopher R.

    2013-01-01

    Little is known about individual differences in integrating numeric base-rates and qualitative text in making probability judgments. Fuzzy-Trace Theory predicts a preference for fuzzy processing. We conducted six studies to develop the FPPI, a reliable and valid instrument assessing individual differences in this fuzzy processing preference. It…

  9. Cultural Practices and the Conception of Individual Differences: Theoretical and Empirical Considerations.

    Science.gov (United States)

    Nunes, Terezinha

    1995-01-01

    Considers empirical evidence and theoretical issues that point out the need to reconceptualize individual differences in psychology. Studies use of arithmetic in everyday life and in the classrooms to explore consequences of cultural practices, the nature of individual differences in "ability," and links between practices and identity.…

  10. 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…

  11. Individual differences in anxiety predict neural measures of visual working memory for untrustworthy faces

    OpenAIRE

    Meconi, Federica; Luria, Roy; Sessa, Paola

    2014-01-01

    When facing strangers, one of the first evaluations people perform is to implicitly assess their trustworthiness. However, the underlying processes supporting trustworthiness appraisal are poorly understood. We hypothesized that visual working memory (VWM) maintains online face representations that are sensitive to physical cues of trustworthiness, and that differences among individuals in representing untrustworthy faces are associated with individual differences in anxiety. Participants per...

  12. Individual differences in reactions towards color in simulated healthcare environments: The role of stimulus screening ability

    NARCIS (Netherlands)

    Dijkstra, K.; Pieterse, M.E.; Pruyn, A.Th.H.

    2008-01-01

    The notion that the physical healthcare environment can affect our mood and behavior is well established. Despite this, individual differences in sensitivity to environmental stimuli have not received much attention. With the current research showing the importance of individual differences in sensi

  13. The Effects of Individual Differences in Cognitive Styles on decision-Making Accuracy and Latency

    Science.gov (United States)

    2003-02-01

    L., Grenblo, P., & Dean, J. B. (2002). Judgmental self-doubt: beliefs about one’s judgmental prowess. Personality and Individual Differences , 33 741...1998). Personal need for structure, the Einstellung task, and the effects of stress. Personality and Individual Differences , 24, 305-310. 29. Somers, M

  14. Individual differences in the encoding processes of egocentric and allocentric survey knowledge.

    Science.gov (United States)

    Wen, Wen; Ishikawa, Toru; Sato, Takao

    2013-01-01

    This study examined how different components of working memory are involved in the acquisition of egocentric and allocentric survey knowledge by people with a good and poor sense of direction (SOD). We employed a dual-task method and asked participants to learn routes from videos with verbal, visual, and spatial interference tasks and without any interference. Results showed that people with a good SOD encoded and integrated knowledge about landmarks and routes into egocentric survey knowledge in verbal and spatial working memory, which is then transformed into allocentric survey knowledge with the support of all three components, distances being processed in verbal and spatial working memory and directions in visual and spatial working memory. In contrast, people with a poor SOD relied on verbal working memory and lacked spatial processing, thus failing to acquire accurate survey knowledge. Based on the results, a possible model for explaining individual differences in spatial knowledge acquisition is proposed. Copyright © 2012 Cognitive Science Society, Inc.

  15. Individual balanced scorecard based on innovative models of personality structure

    Directory of Open Access Journals (Sweden)

    A.A. Polozov

    2013-06-01

    Full Text Available Article focuses on integration of different views on personality structure, which comprises the type of person, the type of character and several types of intelligence. The paper shows practical application of the concept. Graduates who seek to realize their career must comply with the activities of his personality type, the type of character and the dominant type of intelligence.The aim of the article. The aim of the article is to offer the variant of integrating various psychological doctrines. This variant must have higher convergence of expected and actual behavior of selected groups than any of the local concepts. Personal balanced scorecard based on the innovative model of personality structure is building in the article.Practical work was carried out by the authors on the two groups of students. The main condition for the practical work was the fact that students do not impose something.The results of the analysis. We defined that personality structure is a complex concept. It is important to combine different views on the structure of individual and to include various aspects. From the analysis of other authors works we found out that BSC idea is to balance system performance in four groups. The first group includes traditional financial performance. The second group describes external environment of the company and its relationship with customers. The third group describes internal processes of the enterprise. The fourth group allows us to describe the company's ability to learn and grow.Conclusions and directions of further researches. The focus of interest is mainly determined by the type of personality. However, the selection should be such that:consistent hierarchy of motives at this age;trends of economy in general and in the chosen industry in particular;supported by appropriate kind of intelligence;absorbed all of the recommended activity profiles as private.

  16. Genetic Correlates of Individual Differences in Sleep Behavior of Free-Living Great Tits (Parus major

    Directory of Open Access Journals (Sweden)

    Erica F. Stuber

    2016-03-01

    Full Text Available Within populations, free-living birds display considerable variation in observable sleep behaviors, reflecting dynamic interactions between individuals and their environment. Genes are expected to contribute to repeatable between-individual differences in sleep behaviors, which may be associated with individual fitness. We identified and genotyped polymorphisms in nine candidate genes for sleep, and measured five repeatable sleep behaviors in free-living great tits (Parus major, partly replicating a previous study in blue tits (Cyanistes caeruleus. Microsatellites in the CLOCK and NPAS2 clock genes exhibited an association with sleep duration relative to night length, and morning latency to exit the nest box, respectively. Furthermore, microsatellites in the NPSR1 and PCSK2 genes associated with relative sleep duration and proportion of time spent awake at night, respectively. Given the detection rate of associations in the same models run with random markers instead of candidate genes, we expected two associations to arise by chance. The detection of four associations between candidate genes and sleep, however, suggests that clock genes, a clock-related gene, or a gene involved in the melanocortin system, could play key roles in maintaining phenotypic variation in sleep behavior in avian populations. Knowledge of the genetic architecture underlying sleep behavior in the wild is important because it will enable ecologists to assess the evolution of sleep in response to selection.

  17. Genetic Correlates of Individual Differences in Sleep Behavior of Free-Living Great Tits (Parus major).

    Science.gov (United States)

    Stuber, Erica F; Baumgartner, Christine; Dingemanse, Niels J; Kempenaers, Bart; Mueller, Jakob C

    2016-01-06

    Within populations, free-living birds display considerable variation in observable sleep behaviors, reflecting dynamic interactions between individuals and their environment. Genes are expected to contribute to repeatable between-individual differences in sleep behaviors, which may be associated with individual fitness. We identified and genotyped polymorphisms in nine candidate genes for sleep, and measured five repeatable sleep behaviors in free-living great tits (Parus major), partly replicating a previous study in blue tits (Cyanistes caeruleus). Microsatellites in the CLOCK and NPAS2 clock genes exhibited an association with sleep duration relative to night length, and morning latency to exit the nest box, respectively. Furthermore, microsatellites in the NPSR1 and PCSK2 genes associated with relative sleep duration and proportion of time spent awake at night, respectively. Given the detection rate of associations in the same models run with random markers instead of candidate genes, we expected two associations to arise by chance. The detection of four associations between candidate genes and sleep, however, suggests that clock genes, a clock-related gene, or a gene involved in the melanocortin system, could play key roles in maintaining phenotypic variation in sleep behavior in avian populations. Knowledge of the genetic architecture underlying sleep behavior in the wild is important because it will enable ecologists to assess the evolution of sleep in response to selection.

  18. Individual differences in the onset of tense marking: a growth-curve analysis.

    Science.gov (United States)

    Hadley, Pamela A; Holt, Janet K

    2006-10-01

    The purpose of this study was to explore individual differences in children's tense onset growth trajectories and to determine whether any within- or between-child predictors could account for these differences. Twenty-two children with expressive vocabulary abilities in the low-average to below-average range participated. Sixteen children were at risk for specific language impairment (SLI), and 6 children had low-average language abilities. Spontaneous language samples, obtained at 3-month intervals between 2;0 and 3;0, were analyzed to examine change in a cumulative productivity score for 5 tense morphemes: third person singular present, past tense, copula BE, auxiliary BE, and auxiliary DO. Hierarchical linear modeling was used to model intercept and linear growth at 30 months and quadratic growth overall. A growth model that included mean length of utterance (MLU) and MLU growth better explained within-child productivity score growth trajectories than a parallel model with vocabulary and vocabulary growth. Significant linear growth in productivity scores remained even after a control for MLU was in place. When between-child predictors were added in the final conditional model, only positive family history approached statistical significance, improving the overall estimation of the model's growth parameters. The findings support theoretical models of language acquisition that claim relative independence of tense marking from other more general aspects of vocabulary development and sentence length. The trends for family history are also consistent with proposals implicating faulty genetic mechanisms underlying developmental language disorders. Systematic use of familial risk data is recommended in future investigations examining the relationship between late-talking children and children at risk for SLI.

  19. 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…

  20. Development and validation of an individual based Daphnia magna population model: The influence of crowding on population dynamics

    NARCIS (Netherlands)

    Preuss, T.G.; Hammers-Wirtz, M.; Hommen, U.; Rubach, M.N.; Ratte, H.T.

    2009-01-01

    An individual-based model was developed to predict the population dynamics of Daphnia magna at laboratory conditions from individual life-history traits observed in experiments with different feeding conditions. Within the model, each daphnid passes its individual life cycle including feeding on alg

  1. Markovian Building Blocks for Individual-Based Modelling

    DEFF Research Database (Denmark)

    Nilsson, Lars Anders Fredrik

    2007-01-01

    The present thesis consists of a summary report, four research articles, one technical report and one manuscript. The subject of the thesis is individual-based stochastic models. The summary report is composed of three parts and a brief history of some basic models in population biology....... This history is included in order to provide a reader that has no previous exposure to models in population biology with a sufficient background to understand some of the biological models that are mentioned in the thesis. The first part of the rest of the summary is a description of the dramatic changes...... in the degree of aggregation of sprat or herring in the Baltic during the day, with special focus on the dispersion of the fish from schools at dusk. The next part is a brief introduction to Markovian arrival processes, a type of stochastic processes with potential applications as sub-models in population...

  2. 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.

  3. Linking individual-tree and whole-stand models for forest growth and yield prediction

    Directory of Open Access Journals (Sweden)

    Quang V Cao

    2014-10-01

    Full Text Available Background Different types of growth and yield models provide essential information for making informed decisions on how to manage forests. Whole-stand models often provide well-behaved outputs at the stand level, but lack information on stand structures. Detailed information from individual-tree models and size-class models typically suffers from accumulation of errors. The disaggregation method, in assuming that predictions from a whole-stand model are reliable, partitions these outputs to individual trees. On the other hand, the combination method seeks to improve stand-level predictions from both whole-stand and individual-tree models by combining them. Methods Data from 100 plots randomly selected from the Southwide Seed Source Study of loblolly pine (Pinus taeda L. were used to evaluate the unadjusted individual-tree model against the disaggregation and combination methods. Results Compared to the whole-stand model, the combination method did not show improvements in predicting stand attributes in this study. The combination method also did not perform as well as the disaggregation method in tree-level predictions. The disaggregation method provided the best predictions of tree- and stand-level survival and growth. Conclusions The disaggregation approach provides a link between individual-tree models and whole-stand models, and should be considered as a better alternative to the unadjusted tree model.

  4. Glutamate and choline levels predict individual differences in reading ability in emergent readers.

    Science.gov (United States)

    Pugh, Kenneth R; Frost, Stephen J; Rothman, Douglas L; Hoeft, Fumiko; Del Tufo, Stephanie N; Mason, Graeme F; Molfese, Peter J; Mencl, W Einar; Grigorenko, Elena L; Landi, Nicole; Preston, Jonathan L; Jacobsen, Leslie; Seidenberg, Mark S; Fulbright, Robert K

    2014-03-12

    Reading disability is a brain-based difficulty in acquiring fluent reading skills that affects significant numbers of children. Although neuroanatomical and neurofunctional networks involved in typical and atypical reading are increasingly well characterized, the underlying neurochemical bases of individual differences in reading development are virtually unknown. The current study is the first to examine neurochemistry in children during the critical period in which the neurocircuits that support skilled reading are still developing. In a longitudinal pediatric sample of emergent readers whose reading indicators range on a continuum from impaired to superior, we examined the relationship between individual differences in reading and reading-related skills and concentrations of neurometabolites measured using magnetic resonance spectroscopy. Both continuous and group analyses revealed that choline and glutamate concentrations were negatively correlated with reading and related linguistic measures in phonology and vocabulary (such that higher concentrations were associated with poorer performance). Correlations with behavioral scores obtained 24 months later reveal stability for the relationship between glutamate and reading performance. Implications for neurodevelopmental models of reading and reading disability are discussed, including possible links of choline and glutamate to white matter anomalies and hyperexcitability. These findings point to new directions for research on gene-brain-behavior pathways in human studies of reading disability.

  5. Predicting individual responses to pravastatin using a physiologically based kinetic model for plasma cholesterol concentrations

    NARCIS (Netherlands)

    Pas, N.C.A. van de; Rullmann, J.A.C.; Woutersen, R.A.; Ommen, B. van; Rietjens, I.M.C.M.; Graaf, A.A. de

    2014-01-01

    We used a previously developed physiologically based kinetic (PBK) model to analyze the effect of individual variations in metabolism and transport of cholesterol on pravastatin response. The PBK model is based on kinetic expressions for 21 reactions that interconnect eight different body

  6. Time to see the bigger picture: Individual differences in the attentional blink.

    Science.gov (United States)

    Willems, Charlotte; Martens, Sander

    2016-10-01

    If two to-be-identified targets are presented in close temporal succession, identification for the second target is typically impaired. This attentional blink (AB) phenomenon has long been considered as a robust, universal cognitive limitation. However, more recent studies have demonstrated that AB task performance greatly differs between individuals, with some individuals even showing no AB in certain paradigms. Several studies have focused on these individual differences in an attempt to reveal the mechanism underlying the AB, but an overview of this approach is currently missing. Here, by reviewing studies regarding individual differences in AB task performance, we investigate how individual differences have contributed to our understanding of the AB. We show that the individual differences AB literature provides reliable indications that the AB is a multifaceted phenomenon that presumably arises from a combination of factors; individuals with higher levels of executive working memory (WM) functioning and broad attentional focus perform better in the AB paradigm than individuals with lower executive functioning of WM and narrow attentional focus. As it turns out, seeing the bigger picture certainly seems helpful for AB task performance.

  7. 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

  8. Individual-based lattice model for spatial spread of epidemics

    Directory of Open Access Journals (Sweden)

    Henryk Fuks

    2001-01-01

    Full Text Available We present a lattice gas cellular automaton (LGCA to study spatial and temporal dynamics of an epidemic of SIR (susceptible-infected-removed type. The automaton is fully discrete, i.e., space, time and number of individuals are discrete variables. The automaton can be applied to study spread of epidemics in both human and animal populations. We investigate effects of spatial inhomogeneities in initial distribution of infected and vaccinated populations on the dynamics of epidemic of SIR type. We discuss vaccination strategies which differ only in spatial distribution of vaccinated individuals. Also, we derive an approximate, mean-field type description of the automaton, and discuss differences between the mean-field dynamics and the results ofLGCA simulation.

  9. Review of Problems in Research of Individual Differences in Second Language Acquisition

    Institute of Scientific and Technical Information of China (English)

    LIU Fei

    2015-01-01

    Although research on individual differences became the mainstream in SLA, it still obviously lag behind research on similarities over the whole. In order to find a clear developing direction for research in this field, main problems and difficulties arose in earlier research will be discussed. Suggestions and prospects for research on individual differences of SLA will be also pro⁃posed. The ideal of modifying one’s way of teaching to suit the special requirements of each class or case should be the main trend of research on individual differences of SLA.

  10. The effects of individual differences and charismatic leadership on workplace aggression.

    Science.gov (United States)

    Hepworth, Willie; Towler, Annette

    2004-04-01

    This study examined the effects of individual differences variables (trait anger, self-control, negative affectivity, attitudes toward revenge, and attributional style) and charismatic leadership on incidents of workplace aggression in a sample of 213 employees from a wide range of organizations. Hierarchical multiple regression analyses indicated that the individual differences variables accounted for 27% of the variance in workplace aggression and that charismatic leadership accounted for an additional 3% after controlling for individual differences. In addition, psychological empowerment partially mediated the relationship between charismatic leadership and workplace aggression.

  11. 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

    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......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...... 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...

  12. Are individual differences in reading speed related to extrafoveal visual acuity and crowding?

    Directory of Open Access Journals (Sweden)

    Romy Frömer

    Full Text Available Readers differ considerably in their speed of self-paced reading. One factor known to influence fixation durations in reading is the preprocessing of words in parafoveal vision. Here we investigated whether individual differences in reading speed or the amount of information extracted from upcoming words (the preview benefit can be explained by basic differences in extrafoveal vision--i.e., the ability to recognize peripheral letters with or without the presence of flanking letters. Forty participants were given an adaptive test to determine their eccentricity thresholds for the identification of letters presented either in isolation (extrafoveal acuity or flanked by other letters (crowded letter recognition. In a separate eye-tracking experiment, the same participants read lists of words from left to right, while the preview of the upcoming words was manipulated with the gaze-contingent moving window technique. Relationships between dependent measures were analyzed on the observational level and with linear mixed models. We obtained highly reliable estimates both for extrafoveal letter identification (acuity and crowding and measures of reading speed (overall reading speed, size of preview benefit. Reading speed was higher in participants with larger uncrowded windows. However, the strength of this relationship was moderate and it was only observed if other sources of variance in reading speed (e.g., the occurrence of regressive saccades were eliminated. Moreover, the size of the preview benefit--an important factor in normal reading--was larger in participants with better extrafoveal acuity. Together, these results indicate a significant albeit moderate contribution of extrafoveal vision to individual differences in reading speed.

  13. Measuring individual differences in driver inattention: further validation of the attention-related driving errors scale.

    Science.gov (United States)

    Ledesma, Rubén Daniel; Montes, Silvana Andrea; Poó, Fernando Martín; López-Ramón, María Fernanda

    2015-03-01

    The aim of this research was (a) to study driver inattention as a trait-like variable and (b) to provide new evidence of validity for the Attention-Related Driving Errors Scale (ARDES). Driving inattention is approached from an individual differences perspective. We are interested in how drivers vary in their propensity to experience failures of attention and in the methods to measure these differences. In a first sample (n = 301), we tested, via confirmatory factor analysis, a new theoretical model for the ARDES. In a second sample (n = 201), we evaluated the relationship between inattention and internal and external sources of distraction and social desirability bias in ARDES responses. A subsample (n = 65) was reevaluated to study temporal stability of the ARDES scores. Errors measured by the ARDES can be classified according to the driving task level at which they occur (navigation, maneuvering, or control). Differences in ARDES scores based on collision history were observed. ARDES was related to internal sources of distraction and was independent of the level of exposure to distracting activities. Test-retest showed a high degree of stability in ARDES scores. Low correlations were found with a social desirability measure. ARDES appears to measure a personal trait that remains relatively stable over time and is relatively independent of distracting activities. New evidence of validity emerged for this self-report. ARDES can be used to measure individual differences in driving inattention and to help tailor preventive interventions for inattentive drivers. It can serve as an instrument of driver self-assessment in educational and training contexts. © 2014, Human Factors and Ergonomics Society.

  14. 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.

  15. Familiarity is related to conceptual implicit memory: an examination of individual differences.

    Science.gov (United States)

    Wang, Wei-chun; Yonelinas, Andrew P

    2012-12-01

    Explicit memory is thought to be distinct from implicit memory. However, growing evidence has indicated that explicit familiarity-based recognition memory judgments rely on the same process that supports conceptual implicit memory. We tested this hypothesis by examining individual differences using a paradigm wherein we measured both familiarity and conceptual implicit memory within the same participants. In Experiments 1a and 1b, we examined recognition memory confidence ROCs and remember/know responses, respectively, to estimate recollection and familiarity, and used a free association task to measure conceptual implicit memory. The results demonstrated that, across participants, familiarity, but not recollection, was significantly correlated with conceptual priming. In contrast, in Experiment 2, utilizing a similar paradigm, a comparison of recognition memory ROCs and explicit associative cued-recall performance indicated that cued recall was related to both recollection and familiarity. These results are consistent with models assuming that familiarity-based recognition and conceptual implicit memory rely on similar underlying processes.

  16. Personalized Media: A Genetically Informative Investigation of Individual Differences in Online Media Use

    Science.gov (United States)

    Ayorech, Ziada; von Stumm, Sophie; Haworth, Claire M. A.; Davis, Oliver S. P.; Plomin, Robert

    2017-01-01

    Online media use has become an increasingly important behavioral domain over the past decade. However, studies into the etiology of individual differences in media use have focused primarily on pathological use. Here, for the first time, we test the genetic influences on online media use in a UK representative sample of 16 year old twins, who were assessed on time spent on educational (N = 2,585 twin pairs) and entertainment websites (N = 2,614 twin pairs), time spent gaming online (N = 2,635 twin pairs), and Facebook use (N = 4,333 twin pairs). Heritability was substantial for all forms of online media use, ranging from 34% for educational sites to 37% for entertainment sites and 39% for gaming. Furthermore, genetics accounted for 24% of the variance in Facebook use. Our results support an active model of the environment, where young people choose their online engagements in line with their genetic propensities. PMID:28114386

  17. Do individual differences in reinforcement smoking moderate the relationship between affect and urge to smoke?

    Science.gov (United States)

    Leventhal, Adam M

    2010-01-01

    The elucidation of individual differences in tobacco use motivation is of considerable interest. Accordingly, the present study tested the hypothesis that between-person variation in reinforcement smoking (RS)--a tendency to smoke to regulate affect--moderates the relationship between poor mood and urge to smoke. In this cross-sectional, correlational study, smokers (N = 212; > or =5 cig/day) completed measures of RS, positive affect (PA), negative affect (NA), and smoking urge. RS significantly moderated the relation between PA and urge (betas > .11, ps positively correlated with urge in the overall sample (rs = .34, ps < .0001), but RS did not moderate this relationship. The overall results were consistent across 2 measures of mood and adjusted models that controlled for demographics and smoking characteristics. Continued investigation of these moderational pathways could identify which smokers may benefit most from treatments that target mood during smoking cessation.

  18. 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

    2014-11-01

    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.

  19. 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…

  20. Resting EEG in Alpha and Beta Bands Predicts Individual Differences in Attentional Blink Magnitude

    Science.gov (United States)

    MacLean, Mary H.; Arnell, Karen M.; Cote, Kimberly A.

    2012-01-01

    Accuracy for a second target (T2) is reduced when it is presented within 500 ms of a first target (T1) in a rapid serial visual presentation (RSVP)--an attentional blink (AB). There are reliable individual differences in the magnitude of the AB. Recent evidence has shown that the attentional approach that an individual typically adopts during a…

  1. 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…

  2. 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.

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

    NARCIS (Netherlands)

    Schmettow, M.; Noordzij, M.L.; 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 ov

  4. TMFA: A FORTRAN Program for Three-Mode Factor Analysis and Individual Differences Multidimensional Scaling.

    Science.gov (United States)

    Redfield, Joel

    1978-01-01

    TMFA, a FORTRAN program for three-mode factor analysis and individual-differences multidimensional scaling, is described. Program features include a variety of input options, extensive preprocessing of input data, and several alternative methods of analysis. (Author)

  5. Integration of individual and social information for decision-making in groups of different sizes

    National Research Council Canada - National Science Library

    Seongmin A Park; Sidney Goïame; Jean-Claude Dreher

    2017-01-01

    ... (individual information) with those of others (social information). Here, we investigated the neurocomputational mechanisms of how we adapt our judgments to those made by groups of different sizes, in the context of jury decisions for a criminal...

  6. Individual differences in metabolomics: individualised responses and between-metabolite relationships.

    NARCIS (Netherlands)

    Jansen, J.J.; Szymanska, E.; Hoefsloot, H.C.J.; Smilde, A.K.

    2012-01-01

    Many metabolomics studies aim to find 'biomarkers': sets of molecules that are consistently elevated or decreased upon experimental manipulation. Biological effects, however, often manifest themselves along a continuum of individual differences between the biological replicates in the experiment.

  7. 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.

  8. 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.

  9. 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.

  10. Differential Gene Expression Profile in the Rat Caudal Vestibular Nucleus is Associated with Individual Differences in Motion Sickness Susceptibility

    National Research Council Canada - National Science Library

    Wang, Jun-Qin; Qi, Rui-Rui; Zhou, Wei; Tang, Yi-Fan; Pan, Lei-Lei; Cai, Yi-Ling

    2015-01-01

    ... model of the spatial environment [3,4]. According to the 'postural instability theory', the occurrence of motion sickness may be associated with preceding unstable postural control at locomotive surroundings on mobile devices [5-7]. However, these theories do not explain apparent individual differences in MS susceptibility, let alone provide detailed i...

  11. Individual Differences in Navigation between Sharable Content Objects--An Evaluation Study of a Learning Module Prototype.

    Science.gov (United States)

    Gauss, Boris; Urbas, Leon

    2003-01-01

    Reports the design and evaluation of a prototype for learning modules compliant to the SCORM (Sharable Content Object Reference Model) standard for use with hypermedia systems in Web-based instruction. Discusses a study of undergraduates that considered relations between individual differences in learner characteristics, including intrinsic…

  12. 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.

  13. 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).

  14. Individual brain structure and modelling predict seizure propagation.

    Science.gov (United States)

    Proix, Timothée; Bartolomei, Fabrice; Guye, Maxime; Jirsa, Viktor K

    2017-03-01

    See Lytton (doi:10.1093/awx018) for a scientific commentary on this article.Neural network oscillations are a fundamental mechanism for cognition, perception and consciousness. Consequently, perturbations of network activity play an important role in the pathophysiology of brain disorders. When structural information from non-invasive brain imaging is merged with mathematical modelling, then generative brain network models constitute personalized in silico platforms for the exploration of causal mechanisms of brain function and clinical hypothesis testing. We here demonstrate with the example of drug-resistant epilepsy that patient-specific virtual brain models derived from diffusion magnetic resonance imaging have sufficient predictive power to improve diagnosis and surgery outcome. In partial epilepsy, seizures originate in a local network, the so-called epileptogenic zone, before recruiting other close or distant brain regions. We create personalized large-scale brain networks for 15 patients and simulate the individual seizure propagation patterns. Model validation is performed against the presurgical stereotactic electroencephalography data and the standard-of-care clinical evaluation. We demonstrate that the individual brain models account for the patient seizure propagation patterns, explain the variability in postsurgical success, but do not reliably augment with the use of patient-specific connectivity. Our results show that connectome-based brain network models have the capacity to explain changes in the organization of brain activity as observed in some brain disorders, thus opening up avenues towards discovery of novel clinical interventions. © The Author (2017). Published by Oxford University Press on behalf of the Guarantors of Brain.

  15. Trait-Based Individual Differences on Discomfort Glare Rating Responses and Related Visual Contrast Sensitivity

    OpenAIRE

    Mekaroonreung, Haruetai

    2003-01-01

    This research was designed to investigate the relationship between Trait-based Individual differences (neuroticism and extraversion) and glare subjective responses as well as the actual contrast sensitivity when exposed to the same manipulated glare condition. In addition, the relationship between the glare subjective responses and actual contrast sensitivity was investigated. To examine the trait-based individual differences, the International Personality Item Pool (IPIP) was used while th...

  16. Individual Differences in Adult Learners of English as a Foreign Language at Two Levels of Proficiency

    OpenAIRE

    2014-01-01

    [eng] In today’s globalised world it is becoming increasingly common that adults need to learn new languages at any age. And while the number of foreign language adult learners keeps growing, there is still a dearth of research aiming at elucidating what individual differences explain variation in foreign language learning outcomes in students placed in schools which do not have any entry requirements. This study investigated which individual differences impact second language acquisiti...

  17. How Studies of Wild and Captive Dolphins Contribute to our Understanding of Individual Differences and Personality

    OpenAIRE

    Highfill, Lauren E.; Kuczaj II, Stan A.

    2010-01-01

    The study of individual differences in animals and humans has flourished in recent years. This work has revealed personality traits in a wide range of species, including dolphins. However, there are few systematic studies of dolphin personality despite many reasons to assume that personality plays an important role in dolphin behavior. Dolphins live in complex societies and demonstrate a broad and diverse behavioral repertoire, which allows for the possibility of consistent individual differe...

  18. 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.

  19. 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.

  20. The effects of tree species grouping in tropical rain forest modelling - simulations with the individual based model FORMIND

    OpenAIRE

    Köhler, Peter; Huth, A.

    1998-01-01

    Due to high biodiversity in tropical rainforests, tree species are aggregatedinto functional groups for modelling purposes. In this article the influencesof two different classifications of tropical tree species into functionalgroups on the output of a rainforest model are analysed. The FORMIND modelis documented. FORMIND simulates the tree growth of tropical rainforests.The model is individual-based and developed from the FORMIX3 model. In themodel, trees compete for light and space in plots...

  1. Covariation between personalities and individual differences in coping with stress: Converging evidence and hypotheses

    Directory of Open Access Journals (Sweden)

    Claudio CARERE, Doretta CARAMASCHI, Tim W. FAWCETT

    2010-12-01

    Full Text Available In the past decade there has been a profusion of studies highlighting covariation between individual differences in stress physiology and behavioural profiles, here called personalities. Such individual differences in ways of coping with stress are relevant both in biomedicine, since different personalities may experience a different stress and disease vulnerability, and in behavioural ecology, since their adaptive value and evolutionary maintenance are the subject of debate. However, the precise way in which individual stress differences and personalities are linked is unclear. Here we provide an updated overview of this covariation across different species and taxa, consider its functional significance and present working hypotheses for how behavioural and physiological responses to stress might be causally linked, affecting life-history traits such as dispersal and life-span [Current Zoology 56 (6: 728–740, 2010].

  2. 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).

  3. Vive les differences! Individual variation in neural mechanisms of executive control

    Science.gov (United States)

    Braver, Todd S.; Cole, Michael W.; Yarkoni, Tal

    2010-01-01

    Summary Investigations of individual differences have become increasingly important in the cognitive neuroscience of executive control. For instance, individual variation in lateral prefrontal cortex function (and that of associated regions) has recently been used to identify contributions of executive control processes to a number of domains, including working memory capacity, anxiety, reward/motivation, and emotion regulation. However, the origins of such individual differences remain poorly understood. Recent progress toward identifying the genetic and environmental sources of variation in neural traits, in combination with progress identifying the causal relationships between neural and cognitive processes, will be essential for developing a mechanistic understanding of executive control. PMID:20381337

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

    Science.gov (United States)

    Duijster, Denise; van Loveren, Cor; Dusseldorp, Elise; Verrips, Gijsbert H W

    2014-04-01

    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) scores were extracted from dental records. A validated parental questionnaire was used to collect data on sociodemographic characteristics, psychosocial factors, and oral hygiene behaviours. Data on neighbourhood quality were obtained from the Dutch Central Bureau of Statistics. Structural equation modelling indicated that the model was valid after applying a few modifications. In the revised model, lower maternal education level was related to poorer family organization, lower levels of social support, lower dental self-efficacy, and an external dental health locus of control. These, in turn, were associated with poorer oral hygiene behaviours, which were linked to higher levels of childhood dental caries. In addition, lower maternal education level and poorer neighbourhood quality were directly associated with higher caries levels in children. This model advances our understanding of determinants of childhood dental caries and the pathways in which they operate. Conception of these pathways is essential for guiding the development of caries-preventive programmes for children. Clues for further development of the model are suggested.

  5. 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.

  6. Social vigilantism: measuring individual differences in belief superiority and resistance to persuasion.

    Science.gov (United States)

    Saucier, Donald A; Webster, Russell J

    2010-01-01

    Social vigilantism (SV) is an enduring individual difference that assesses the tendency of individuals to impress and propagate their "superior" beliefs onto others to correct others' more "ignorant" opinions. After establishing a reliable measure of SV, three studies showed that SV was associated with greater expressions of belief superiority (whether reacting to others holding dissimilar or similar beliefs) and greater resistance to persuasion (via increased rates of counterarguing and greater attitude stability after persuasion appeals) even after controlling for relevant individual differences (narcissism, dogmatism, psychological reactance, and need for cognition), as well as attitude importance and extremity. Thus, SV predicts expressions of belief superiority and resistance to persuasion above and beyond characteristics of the attitude and individual difference variables previously studied in the attitude literature. SV is a meaningful construct in increasing the understanding of persuasion, attitude resistance, and attitude dissemination that can be applied in a variety of psychological domains.

  7. 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.

  8. Individual differences in the interoceptive states of hunger, fullness and thirst.

    Science.gov (United States)

    Stevenson, Richard J; Mahmut, Mehmet; Rooney, Kieron

    2015-12-01

    Interoception is the ability to perceive internal bodily states. This involves the detection and awareness of static and changing afferent signals from the viscera, motivational states, affective reactions, and associated cognitions. We examined whether there are individual differences in any or all of these aspects of ingestion-related interoception and their possible causes. Individual variation in almost all aspects of interoception was documented for hunger, fullness and thirst - including how participants use, prioritise and integrate visceral, motivational, affective and cognitive information. Individual differences may arise from multiple causes, including genetic influences, developmental changes hypothesised to result from child feeding practices, and from conditions such as depression, anxiety, eating disorders and certain subtypes of obesity. A nutritionally poor diet, and dietary restraint, may also affect ingestion-related interoception. Finally, certain forms of brain injury, notably to the medial temporal lobes are associated with impaired ingestion-related interoception. We conclude by examining the practical and theoretical consequences of these individual differences.

  9. Modeling individual effects in the Cormack-Jolly-Seber Model: A state-space formulation

    Science.gov (United States)

    Royle, J. Andrew

    2008-01-01

    In population and evolutionary biology, there exists considerable interest in individual heterogeneity in parameters of demographic models for open populations. However, flexible and practical solutions to the development of such models have proven to be elusive. In this article, I provide a state-space formulation of open population capture-recapture models with individual effects. The state-space formulation provides a generic and flexible framework for modeling and inference in models with individual effects, and it yields a practical means of estimation in these complex problems via contemporary methods of Markov chain Monte Carlo. A straightforward implementation can be achieved in the software package WinBUGS. I provide an analysis of a simple model with constant parameter detection and survival probability parameters. A second example is based on data from a 7-year study of European dippers, in which a model with year and individual effects is fitted.

  10. Attractor-based models for individual and groups’ forecasting

    Science.gov (United States)

    Astakhova, N. N.; Demidova, L. A.; Kuzovnikov, A. V.; Tishkin, R. V.

    2017-02-01

    In this paper the questions of the attractors’ application in case of the development of the forecasting models on the base of the strictly binary trees have been considered. Usually, these models use the short time series as the training data sequence. The application of the principles of the attractors’ forming on the base of the long time series will allow creating the training data sequence more reasonably. The offered approach to creation of the training data sequence for the forecasting models on the base of the strictly binary trees was applied for the individual and groups’ forecasting of time series. At the same time the problems of one-objective and multiobjective optimization on the base of the modified clonal selection algorithm have been considered. The reviewed examples confirm the efficiency of the attractors’ application in sense of minimization of the used quality indicators of the forecasting models, and also the forecasting errors on 1 – 5 steps forward. Besides, the minimization of time expenditures for the development of the forecasting models is provided.

  11. 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.

  12. 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

    2014-12-01

    We examined regional changes in brain volume in healthy adults (N=167, age 19-79years 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 PhG, and individual differences in change were noted in all regions, except the OF. Pro-inflammatory genetic variants modified shrinkage in PhG and CbH. Carriers of two T alleles of interleukin-1β (IL-1β C-511T, rs16944) and a T allele of methylenetetrahydrofolate reductase (MTHFR C677T, 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.

  13. Developmental Trajectories in Toddlers’ Self-restraint Predict Individual Differences in Executive Functions 14 Years Later: A Behavioral Genetic Analysis

    OpenAIRE

    Friedman, Naomi P.; Miyake, Akira; Robinson, JoAnn L.; Hewitt, John K.

    2011-01-01

    We examined whether self-restraint in early childhood predicted individual differences in three executive functions (EFs; inhibiting prepotent responses, updating working memory, and shifting task sets) in late adolescence in a sample of ~950 twins. At ages 14, 20, 24, and 36 months, the children were shown an attractive toy and told not to touch it for 30 seconds. Latency to touch the toy increased with age, and latent class growth modeling distinguished two groups of children that differed ...

  14. 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.

  15. 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.

  16. 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.

  17. Of goals and habits: age-related and individual differences in goal-directed decision-making.

    Science.gov (United States)

    Eppinger, Ben; Walter, Maik; Heekeren, Hauke R; Li, Shu-Chen

    2013-01-01

    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.

  18. 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.

  19. 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.

  20. 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…

  1. Individual recognition in domestic cattle (Bos taurus: evidence from 2D-images of heads from different breeds.

    Directory of Open Access Journals (Sweden)

    Marjorie Coulon

    Full Text Available BACKGROUND: In order to maintain cohesion of groups, social animals need to process social information efficiently. Visual individual recognition, which is distinguished from mere visual discrimination, has been studied in only few mammalian species. In addition, most previous studies used either a small number of subjects or a few various views as test stimuli. Dairy cattle, as a domestic species allow the testing of a good sample size and provide a large variety of test stimuli due to the morphological diversity of breeds. Hence cattle are a suitable model for studying individual visual recognition. This study demonstrates that cattle display visual individual recognition and shows the effect of both familiarity and coat diversity in discrimination. METHODOLOGY/PRINCIPAL FINDINGS: We tested whether 8 Prim'Holstein heifers could recognize 2D-images of heads of one cow (face, profiles, (3/4 views from those of other cows. Experiments were based on a simultaneous discrimination paradigm through instrumental conditioning using food rewards. In Experiment 1, all images represented familiar cows (belonging to the same social group from the Prim'Holstein breed. In Experiments 2, 3 and 4, images were from unfamiliar (unknown individuals either from the same breed or other breeds. All heifers displayed individual recognition of familiar and unfamiliar individuals from their own breed. Subjects reached criterion sooner when recognizing a familiar individual than when recognizing an unfamiliar one (Exp 1: 3.1+/-0.7 vs. Exp 2: 5.2+/-1.2 sessions; Z = 1.99, N = 8, P = 0.046. In addition almost all subjects recognized unknown individuals from different breeds, however with greater difficulty. CONCLUSIONS/SIGNIFICANCE: Our results demonstrated that cattle have efficient individual recognition based on categorization capacities. Social familiarity improved their performance. The recognition of individuals with very different coat characteristics from the

  2. 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.

  3. Multilevel analysis of individual differences in regularities of grapheme-color associations in synesthesia.

    Science.gov (United States)

    Hamada, Daisuke; Yamamoto, Hiroki; Saiki, Jun

    2017-08-01

    Grapheme-color synesthesia is a neurological phenomenon where visual perception of letters and numbers stimulates perception of a specific color. Grapheme-color correspondences have been shown to be systematically associated with grapheme properties, including visual shape difference, ordinality, and frequency. However, the contributions of grapheme factors differ across individuals. In this study, we applied multilevel analysis to test whether individual differences in regularities of grapheme-color associations could be explained by individual styles of processing grapheme properties. These processing styles are reflected by the type of synesthetic experience. Specifically, we hypothesized that processing focusing on shape differences would be associated with projector synesthetes, while processing focusing on ordinality or familiarity would be associated with associator synesthetes. The analysis revealed that ordinality and familiarity factors were expressed more strongly among associators than among projectors. This finding suggests that grapheme-color associations are partly determined by the type of synesthetic experience. Copyright © 2017 Elsevier Inc. All rights reserved.

  4. The influence of sex differences and individual task performance on brain activation during planning.

    Science.gov (United States)

    Unterrainer, J M; Ruff, C C; Rahm, B; Kaller, C P; Spreer, J; Schwarzwald, R; Halsband, U

    2005-01-15

    Several studies have attempted to identify the neuronal basis of sex differences in cognition. However, group differences in cognitive ability rather than genuine neurocognitive differences between the sexes may account for their results. Here, we compare with functional magnetic resonance imaging the relation between gender, individual task performance, and planning-related brain activation. Men and women preselected to display identical performance scores showed a strong relation between individual task performance and activation of the right dorsolateral prefrontal and right inferior parietal cortex activation during a visuospatial planning task. No gender-specific activations were found. However, a different pattern emerged when subjects had to execute the motor responses to the problems. Better performance was associated with right dorsolateral prefrontal and right parahippocampal activations, and females exhibited a stronger right hippocampal activation than males. These findings underline that an individual's performance level rather than his or her sex largely determines the neuronal activation patterns during higher-level cognition.

  5. Fraud, individuals, and networks: A biopsychosocial model of scientific frauds.

    Science.gov (United States)

    Leistedt, Samuel J; Linkowski, Paul

    2016-03-01

    The problem of fraud, especially scientific fraud, is global and its identification risk is still in its infancy. Based on an in-depth analysis of several financial and scientific fraud trials, the authors propose a new and integrative model of scientific fraud. This model identifies two major levels for committing fraud: (i) at the personal skills level (micro-level) and (ii) at the network skills level (macro-level). Interacting continuously with each other, they form a dynamic, efficient, and integrative system: an integrative model of fraud. The micro-level refers to three factors: (i) personality organization, (ii) social competence, and (iii) the so-called triangle of fraud. The macro-level refers essentially to social network organization and social engineering. Then, the key to understanding and mostly controlling fraud is to consider both the individual and the environment in which they operate. Based on our model, several steps at the micro- and macro-levels can be proposed. Copyright © 2016 The Chartered Society of Forensic Sciences. Published by Elsevier Ireland Ltd. All rights reserved.

  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. 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…

  8. 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…

  9. Examining the Domain-Specificity of Metacognition Using Academic Domains and Task-Specific Individual Differences

    Science.gov (United States)

    Scott, Brianna M.; Berman, Ashleigh F.

    2013-01-01

    Metacognition refers to students' knowledge and regulation of cognition, as well as their accuracy in predicting their academic performance. This study addressed two major questions: 1) how do metacognitive knowledge, regulation and accuracy differ across domains?, and 2) how do students' individual differences relate to their reported…

  10. Individual Differences in Process Outcomes for Verbal Analogy and Classification Solution.

    Science.gov (United States)

    Alderton, David L.; And Others

    1985-01-01

    Adult performance on verbal analogy and classification problems was assessed in terms of outcomes of process execution. Process-outcomes measures accounted for overall performance and were related to ability. Problem forms differed in terms of which measures predicted individual differences. Common process-outcome measures showed highest…

  11. 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,…

  12. 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.

  13. 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.

  14. 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.

  15. Individual differences in nucleus accumbens dopamine receptors predict development of addiction-like behavior: a computational approach.

    Science.gov (United States)

    Piray, Payam; Keramati, Mohammad Mahdi; Dezfouli, Amir; Lucas, Caro; Mokri, Azarakhsh

    2010-09-01

    Clinical and experimental observations show individual differences in the development of addiction. Increasing evidence supports the hypothesis that dopamine receptor availability in the nucleus accumbens (NAc) predisposes drug reinforcement. Here, modeling striatal-midbrain dopaminergic circuit, we propose a reinforcement learning model for addiction based on the actor-critic model of striatum. Modeling dopamine receptors in the NAc as modulators of learning rate for appetitive--but not aversive--stimuli in the critic--but not the actor--we define vulnerability to addiction as a relatively lower learning rate for the appetitive stimuli, compared to aversive stimuli, in the critic. We hypothesize that an imbalance in this learning parameter used by appetitive and aversive learning systems can result in addiction. We elucidate that the interaction between the degree of individual vulnerability and the duration of exposure to drug has two progressive consequences: deterioration of the imbalance and establishment of an abnormal habitual response in the actor. Using computational language, the proposed model describes how development of compulsive behavior can be a function of both degree of drug exposure and individual vulnerability. Moreover, the model describes how involvement of the dorsal striatum in addiction can be augmented progressively. The model also interprets other forms of addiction, such as obesity and pathological gambling, in a common mechanism with drug addiction. Finally, the model provides an answer for the question of why behavioral addictions are triggered in Parkinson's disease patients by D2 dopamine agonist treatments.

  16. Differences in associations between active transportation and built environmental exposures when expressed using different components of individual activity spaces.

    Science.gov (United States)

    van Heeswijck, Torbjorn; Paquet, Catherine; Kestens, Yan; Thierry, Benoit; Morency, Catherine; Daniel, Mark

    2015-05-01

    This study assessed relationships between built environmental exposures measured within components of individual activity spaces (i.e., travel origins, destinations and paths in-between), and use of active transportation in a metropolitan setting. Individuals (n=37,165) were categorised as using active or sedentary transportation based on travel survey data. Generalised Estimating Equations analysis was used to test relationships with active transportation. Strength and significance of relationships between exposures and active transportation varied for different components of the activity space. Associations were strongest when including travel paths in expression of the built environment. Land use mix and greenness were negatively related to active transportation.

  17. Selection of thrombolytic therapy for individual patients: development of a clinical model

    NARCIS (Netherlands)

    R.M. Califf (Robert); L.H. Woodlief (Lynn); F.E. Harrell (Frank); K.L. Lee (Kerry); H.D. White (Harvey); A.D. Guerci (Alan); G.I. Barbash; R.J. Simes (John); W.D. Weaver; M.L. Simoons (Maarten); E.J. Topol (Eric)

    1997-01-01

    textabstractWe developed a logistic regression model with data from the GUSTO-I trial to predict mortality rate differences in individual patients who received accelerated tissue plasminogen activator (TPA) versus streptokinase treatment for acute myocardial infarction. A nomogram was developed from

  18. Modelling and modal properties of the railway vehicle bogie with two individual wheelset drives

    Directory of Open Access Journals (Sweden)

    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.

  19. Do individual females differ intrinsically in their propensity to engage in extra-pair copulations?

    Directory of Open Access Journals (Sweden)

    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.

  20. 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.

  1. Developmental differences in intra-individual variability in children with ADHD and ASD.

    Science.gov (United States)

    van Belle, Janna; van Hulst, Branko M; Durston, Sarah

    2015-12-01

    Intra-individual variability reflects temporal variation within an individual's performance on a cognitive task. Children with developmental disorders, such as ADHD and ASD show increased levels of intra-individual variability. In typical development, intra-individual variability decreases sharply between the ages 6 and 20. The tight link between intra-individual variability and age has led to the suggestion that it may be marker of neural development. As there is accumulating evidence that ADHD and ASD are characterised by atypical neurodevelopmental trajectories, we set out to explore developmental changes in intra-individual variability in subjects with ADHD and ASD. We used propensity score matching to match a cross-sectional sample of children with ADHD, ASD and control subjects (N = 405, aged 6-19 years old) for age, IQ and gender. We used ex-Gaussian distribution parameters to characterise intra-individual variability on fast responses (sigma) and slow responses (tau). Results showed that there was a similar decrease in mean response times with age across groups, and an interaction between age and group for measures of variability, where there was a much lower rate of change in the variability parameters (sigma and tau) for subjects with ASD compared with the other two groups. Subjects with ADHD had higher intra-individual variability, reflected by both sigma and tau, but the rate of decrease in variability with age was similar to that of the controls. These results suggest that subjects with ADHD, ASD and controls differ in the rate at which intra-individual variability decreases during development, and support the idea that intra-individual variability may be a marker of neural development, mimicking the neurodevelopmental changes in these disorders. © 2015 Association for Child and Adolescent Mental Health.

  2. Perceived Risk of Burglary and Fear of Crime: Individual- and Country-Level Mixed Modeling.

    Science.gov (United States)

    Chon, Don Soo; Wilson, Mary

    2016-02-01

    Given the scarcity of prior studies, the current research introduced country-level variables, along with individual-level ones, to test how they are related to an individual's perceived risk of burglary (PRB) and fear of crime (FC), separately, by using mixed-level logistic regression analyses. The analyses of 104,218 individuals, residing in 50 countries, showed that country-level poverty was positively associated with FC only. However, individual-level variables, such as prior property crime victimization and female gender, had consistently positive relationships with both PRB and FC. However, age group and socioeconomic status were inconsistent between those two models, suggesting that PRB and FC are two different concepts. Finally, no significant difference in the pattern of PRB and FC was found between a highly developed group of countries and a less developed one.

  3. 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.

  4. Steady States in SIRS Epidemical Model of Mobile Individuals

    Science.gov (United States)

    Zhang, Duan-Ming; He, Min-Hua; Yu, Xiao-Ling; Pan, Gui-Jun; Sun, Hong-Zhang; Su, Xiang-Ying; Sun, Fan; Yin, Yan-Ping; 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 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.

  5. The consistency of individual differences in growth, feed efficiency and feeding behaviour in African catfish Clarias gariepinus (Burchell, 1822) housed individually

    NARCIS (Netherlands)

    Matos Martins, de C.I.; Schrama, J.W.; Verreth, J.A.J.

    2005-01-01

    Individual variation in growth, feed intake and feeding behaviour has been previously recognized in several fish species. However, there is a lack of information regarding the consistency of such individual differences, which is important to understand the probability of a certain individual trait

  6. 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.

  7. Major Differences between the Jerome Model and the Horace Model

    Institute of Scientific and Technical Information of China (English)

    朱艳

    2014-01-01

    There are three famous translation models in the field of translation: the Jerome model, the Horace model and the Schleiermacher model. The production and development of the three models have significant influence on the translation. To find the major differences between the two western classical translation theoretical models, we discuss the Jerome model and the Hor-ace model deeply in this paper.

  8. Consistent individual differences in the social phenotypes of wild great tits, Parus major.

    Science.gov (United States)

    Aplin, L M; Firth, J A; Farine, D R; Voelkl, B; Crates, R A; Culina, A; Garroway, C J; Hinde, C A; Kidd, L R; Psorakis, I; Milligan, N D; Radersma, R; Verhelst, B L; Sheldon, B C

    2015-10-01

    Despite growing interest in animal social networks, surprisingly little is known about whether individuals are consistent in their social network characteristics. Networks are rarely repeatedly sampled; yet an assumption of individual consistency in social behaviour is often made when drawing conclusions about the consequences of social processes and structure. A characterization of such social phenotypes is therefore vital to understanding the significance of social network structure for individual fitness outcomes, and for understanding the evolution and ecology of individual variation in social behaviour more broadly. Here, we measured foraging associations over three winters in a large PIT-tagged population of great tits, and used a range of social network metrics to quantify individual variation in social behaviour. We then examined repeatability in social behaviour over both short (week to week) and long (year to year) timescales, and investigated variation in repeatability across age and sex classes. Social behaviours were significantly repeatable across all timescales, with the highest repeatability observed in group size choice and unweighted degree, a measure of gregariousness. By conducting randomizations to control for the spatial and temporal distribution of individuals, we further show that differences in social phenotypes were not solely explained by within-population variation in local densities, but also reflected fine-scale variation in social decision making. Our results provide rare evidence of stable social phenotypes in a wild population of animals. Such stable social phenotypes can be targets of selection and may have important fitness consequences, both for individuals and for their social-foraging associates.

  9. Individualization of psychological training and its importance at different stages of many years’ perfection in tennis

    Directory of Open Access Journals (Sweden)

    Vysochina N.L.

    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.

  10. Individual differences in the preferred neck-resting position of Caribbean flamingos (Phoenicopterus ruber).

    Science.gov (United States)

    Anderson, Matthew J; Williams, Sarah A; O'Brien, Edward H

    2009-01-01

    When resting, flamingos often lay their heads along their backs. While in this position they must curve their necks to either the right or left of their midline. Observations of captive Caribbean flamingos at the Philadelphia Zoo (Philadelphia, PA, USA) were conducted in order to determine if individual birds would display consistent preferences in neck-resting position over multiple observations. While individual birds were shown to vary greatly in regards to the strength and direction of their preferences, a significant flock-level preference towards neck resting to the right was obtained. Analysis of individual flamingos revealed that 5 out of 17 birds displayed preferences that significantly differed from chance, with each of these birds preferring to rest their necks to the right. From the present data we can conclude that flamingos display behavioural laterality of neck-resting position at both the level of the group and that of the individual.

  11. Not Everybody Sees the Ness in the Darkness: Individual Differences in Masked Suffix Priming

    Science.gov (United States)

    Medeiros, Joyse; Duñabeitia, Jon Andoni

    2016-01-01

    The present study explores the role of individual differences in polymorphemic word recognition. Participants completed a masked priming lexical decision experiment on suffixed words in which targets could be preceded by suffix-related words (words sharing the same suffix) or by affixed primes with a different suffix. Participants also completed a monomorphemic word lexical decision and were divided in two groups (fast and slow readers) according to their performance in this task. When the suffix priming data were analyzed taking into consideration participants' reading speed as a proxy for their greater reliance on orthography or on semantics, a significant interaction between reading speed and the magnitude of the masked suffix priming effects emerged. Only slow participants showed significant priming effects, whereas faster participants showed negligible masked suffix priming effects. These results demonstrate that different reading profiles modulate the access to morphological information in a qualitatively different manner and that individual differences in reading determine the manner in which polymorphemic words are processed.

  12. Differences of Confucianism and Individualism on the Development of Chinese and American Personalities

    Institute of Scientific and Technical Information of China (English)

    巢玥

    2015-01-01

    Different personalities are shaped by different cultures.Chinese Confucianism and American Individualism took totally different developing routes.Understanding and contemplating their differences in personality can greatly enhance inter-cultural communication between these two countries.Based on the present researches and studies,this paper discusses the differences and current situation of Chinese and American personalities.Relevant suggestions are initiated aiming at learning from each other’s strong points and bridging the gap as to enhance the development of healthy personality and harmonious world.

  13. 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.

  14. Consistent individual differences in seed disperser quality in a seed-eating fish.

    Science.gov (United States)

    Pollux, Bart J A

    2017-01-01

    Animal-mediated seed dispersal (zoochory) is considered to be an important mechanism regulating biological processes at larger spatial scales. To date, intra-specific variation in seed disperser quality within seed-dispersing animals has not been studied. Here, I employed seed feeding trials to quantify individual differences in disperser quality within the common carp (Cyprinus carpio) using seeds of two aquatic plants: unbranched bur-reed (Sparganium emersum, Sparganiaceae) and arrowhead (Sagittaria sagittifolia, Alismataceae). I found substantial variation among carp individuals in their propensity to ingest seeds and their ability to digest them, resulting in up to 31-fold differences in the probability of seed dispersal. In addition, there were significant differences in the time that seeds are retained in their digestive systems, generating a twofold difference in the maximum distance over which they can potentially disperse seeds. I propose that seed-eating animal species consist of individuals that display continuous variation in disperser quality, with at one end of the continuum individuals that are likely to eat seeds, pass them unharmed through their digestive tract and transport them over large distances to new locations (i.e. high-quality seed dispersers) and at the other end individuals that rarely eat seeds, destroy most of the ones they ingest and transport the few surviving seeds over relatively short distances (low-quality seed dispersers). Although individual differences in seed dispersal quality could be the result of a variety of factors, these results underline the ecological and evolutionary potential of such variation for both plants and animals.

  15. 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

  16. Individual differences in highly skilled visual perceptual-motor striking skill.

    Science.gov (United States)

    Müller, Sean; Brenton, John; Dempsey, Alasdair R; Harbaugh, Allen G; Reid, Corinne

    2015-07-01

    Expertise studies into visual perceptual-motor skills have mainly focused their investigation upon group comparisons rather than individual comparisons. This study investigated the pick-up of visual information to time weight transfer and bat kinematics within an exemplar group of striking sport experts using an in situ temporal occlusion paradigm. Highly skilled cricket batsmen faced bowlers and attempted to strike delivered balls, whilst their vision was either temporally occluded through occlusion glasses prior to ball bounce or not occluded (control condition). A chronometric analysis was conducted on trials in the occlusion condition to quantify the pick-up of visual information to time biomechanical variables. Results indicated that initiation of weight transfer and bat downswing, as well as bat downswing completion, was significantly different between some individual batsmen. No significant difference was found between individual batsmen for time of weight transfer completion. Unexpectedly, it was found that achievement of the goal to strike delivered balls, that is, the frequency of bat-ball contacts was not significantly different between batsmen. Collectively, the findings indicate that individual differences exist in the coordination pattern of a complex whole body visual perceptual-motor skill, but these different patterns are used to achieve a similar outcome, which is known as motor equivalence.

  17. Human brain structure predicts individual differences in preconscious evaluation of facial dominance and trustworthiness.

    Science.gov (United States)

    Getov, Spas; Kanai, Ryota; Bahrami, Bahador; Rees, Geraint

    2015-05-01

    Social cues conveyed by the human face, such as eye gaze direction, are evaluated even before they are consciously perceived. While there is substantial individual variability in such evaluation, its neural basis is unknown. Here we asked whether individual differences in preconscious evaluation of social face traits were associated with local variability in brain structure. Adult human participants (n = 36) monocularly viewed faces varying in dominance and trustworthiness, which were suppressed from awareness by a dynamic noise pattern shown to the other eye. The time taken for faces to emerge from suppression and become visible (t2e) was used as a measure of potency in competing for visual awareness. Both dominant and untrustworthy faces resulted in slower t2e than neutral faces, with substantial individual variability in these effects. Individual differences in t2e were correlated with gray matter volume in right insula for dominant faces, and with gray matter volume in medial prefrontal cortex, right temporoparietal junction and bilateral fusiform face area for untrustworthy faces. Thus, individual differences in preconscious social processing can be predicted from local brain structure, and separable correlates for facial dominance and untrustworthiness suggest distinct mechanisms of preconscious processing. © The Author (2014). Published by Oxford University Press.

  18. Individualization of the parameters of the three-elements Windkessel model using carotid pulse signal

    Science.gov (United States)

    Żyliński, Marek; Niewiadomski, Wiktor; Strasz, Anna; GÄ siorowska, Anna; Berka, Martin; Młyńczak, Marcel; Cybulski, Gerard

    2015-09-01

    The haemodynamics of the arterial system can be described by the three-elements Windkessel model. As it is a lumped model, it does not account for pulse wave propagation phenomena: pulse wave velocity, reflection, and pulse pressure profile changes during propagation. The Modelflowmethod uses this model to calculate stroke volume and total peripheral resistance (TPR) from pulse pressure obtained from finger; the reliability of this method is questioned. The model parameters are: aortic input impedance (Zo), TPR, and arterial compliance (Cw). They were obtained from studies of human aorta preparation. Individual adjustment is performed based on the subject's age and gender. As Cw is also affected by diseases, this may lead to inaccuracies. Moreover, the Modelflowmethod transforms the pulse pressure recording from the finger (Finapres©) into a remarkably different pulse pressure in the aorta using a predetermined transfer function — another source of error. In the present study, we indicate a way to include in the Windkessel model information obtained by adding carotid pulse recording to the finger pressure measurement. This information allows individualization of the values of Cw and Zo. It also seems reasonable to utilize carotid pulse, which better reflects aortic pressure, to individualize the transfer function. Despite its simplicity, the Windkessel model describes essential phenomena in the arterial system remarkably well; therefore, it seems worthwhile to check whether individualization of its parameters would increase the reliability of results obtained with this model.

  19. 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.

  20. Individual differences in the executive control of attention, memory, and thought, and their associations with schizotypy.

    Science.gov (United States)

    Kane, Michael J; Meier, Matt E; Smeekens, Bridget A; Gross, Georgina M; Chun, Charlotte A; Silvia, Paul J; Kwapil, Thomas R

    2016-08-01

    A large correlational study took a latent-variable approach to the generality of executive control by testing the individual-differences structure of executive-attention capabilities and assessing their prediction of schizotypy, a multidimensional construct (with negative, positive, disorganized, and paranoid factors) conveying risk for schizophrenia. Although schizophrenia is convincingly linked to executive deficits, the schizotypy literature is equivocal. Subjects completed tasks of working memory capacity (WMC), attention restraint (inhibiting prepotent responses), and attention constraint (focusing visual attention amid distractors), the latter 2 in an effort to fractionate the "inhibition" construct. We also assessed mind-wandering propensity (via in-task thought probes) and coefficient of variation in response times (RT CoV) from several tasks as more novel indices of executive attention. WMC, attention restraint, attention constraint, mind wandering, and RT CoV were correlated but separable constructs, indicating some distinctions among "attention control" abilities; WMC correlated more strongly with attentional restraint than constraint, and mind wandering correlated more strongly with attentional restraint, attentional constraint, and RT CoV than with WMC. Across structural models, no executive construct predicted negative schizotypy and only mind wandering and RT CoV consistently (but modestly) predicted positive, disorganized, and paranoid schizotypy; stalwart executive constructs in the schizophrenia literature-WMC and attention restraint-showed little to no predictive power, beyond restraint's prediction of paranoia. Either executive deficits are consequences rather than risk factors for schizophrenia, or executive failures barely precede or precipitate diagnosable schizophrenia symptoms. (PsycINFO Database Record

  1. 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.

  2. Group decisions and individual differences: route fidelity predicts flight leadership in homing pigeons (Columba livia).

    Science.gov (United States)

    Freeman, Robin; Mann, Richard; Guilford, Tim; Biro, Dora

    2011-02-23

    How social-living animals make collective decisions is currently the subject of intense scientific interest, with increasing focus on the role of individual variation within the group. Previously, we demonstrated that during paired flight in homing pigeons, a fully transitive leadership hierarchy emerges as birds are forced to choose between their own and their partner's habitual routes. This stable hierarchy suggests a role for individual differences mediating leadership decisions within homing pigeon pairs. What these differences are, however, has remained elusive. Using novel quantitative techniques to analyse habitual route structure, we show here that leadership can be predicted from prior route-following fidelity. Birds that are more faithful to their own route when homing alone are more likely to emerge as leaders when homing socially. We discuss how this fidelity may relate to the leadership phenomenon, and propose that leadership may emerge from the interplay between individual route confidence and the dynamics of paired flight.

  3. 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.

  4. Individual differences in attentional modulation of cortical responses correlate with selective attention performance.

    Science.gov (United States)

    Choi, Inyong; Wang, Le; Bharadwaj, Hari; Shinn-Cunningham, Barbara

    2014-08-01

    Many studies have shown that attention modulates the cortical representation of an auditory scene, emphasizing an attended source while suppressing competing sources. Yet, individual differences in the strength of this attentional modulation and their relationship with selective attention ability are poorly understood. Here, we ask whether differences in how strongly attention modulates cortical responses reflect differences in normal-hearing listeners' selective auditory attention ability. We asked listeners to attend to one of three competing melodies and identify its pitch contour while we measured cortical electroencephalographic responses. The three melodies were either from widely separated pitch ranges ("easy trials"), or from a narrow, overlapping pitch range ("hard trials"). The melodies started at slightly different times; listeners attended either the leading or lagging melody. Because of the timing of the onsets, the leading melody drew attention exogenously. In contrast, attending the lagging melody required listeners to direct top-down attention volitionally. We quantified how attention amplified auditory N1 response to the attended melody and found large individual differences in the N1 amplification, even though only correctly answered trials were used to quantify the ERP gain. Importantly, listeners with the strongest amplification of N1 response to the lagging melody in the easy trials were the best performers across other types of trials. Our results raise the possibility that individual differences in the strength of top-down gain control reflect inherent differences in the ability to control top-down attention.

  5. Individual differences in face-looking behavior generalize from the lab to the world.

    Science.gov (United States)

    Peterson, Matthew F; Lin, Jing; Zaun, Ian; Kanwisher, Nancy

    2016-05-01

    Recent laboratory studies have found large, stable individual differences in the location people first fixate when identifying faces, ranging from the brows to the mouth. Importantly, this variation is strongly associated with differences in fixation-specific identification performance such that individuals' recognition ability is maximized when looking at their preferred location (Mehoudar, Arizpe, Baker, & Yovel, 2014; Peterson & Eckstein, 2013). This finding suggests that face representations are retinotopic and individuals enact gaze strategies that optimize identification, yet the extent to which this behavior reflects real-world gaze behavior is unknown. Here, we used mobile eye trackers to test whether individual differences in face gaze generalize from lab to real-world vision. In-lab fixations were measured with a speeded face identification task, while real-world behavior was measured as subjects freely walked around the Massachusetts Institute of Technology campus. We found a strong correlation between the patterns of individual differences in face gaze in the lab and real-world settings. Our findings support the hypothesis that individuals optimize real-world face identification by consistently fixating the same location and thus strongly constraining the space of retinotopic input. The methods developed for this study entailed collecting a large set of high-definition, wide field-of-view natural videos from head-mounted cameras and the viewer's fixation position, allowing us to characterize subjects' actually experienced real-world retinotopic images. These images enable us to ask how vision is optimized not just for the statistics of the "natural images" found in web databases, but of the truly natural, retinotopic images that have landed on actual human retinae during real-world experience.

  6. Trajectories of brain aging in middle-aged and older adults: regional and individual differences.

    Science.gov (United States)

    Raz, Naftali; Ghisletta, Paolo; Rodrigue, Karen M; Kennedy, Kristen M; Lindenberger, Ulman

    2010-06-01

    The human brain changes with age. However, the rate and the trajectories of change vary among the brain regions and among individuals, and the reasons for these differences are unclear. In a sample of healthy middle-aged and older adults, we examined mean volume change and individual differences in the rate of change in 12 regional brain volumes over approximately 30 months. In addition to the baseline assessment, there were two follow-ups, 15 months apart. We observed significant average shrinkage of the hippocampus, entorhinal cortex, orbital-frontal cortex, and cerebellum in each of the intervals. Shrinkage of the hippocampus accelerated with time, whereas shrinkage of the caudate nucleus, prefrontal subcortical white matter, and corpus callosum emerged only at the second follow-up. Throughout both assessment intervals, the mean volumes of the lateral prefrontal and primary visual cortices, putamen, and pons did not change. Significant individual differences in shrinkage rates were observed in the lateral prefrontal cortex, the cerebellum, and all the white matter regions throughout the study, whereas additional regions (medial-temporal structures, the insula, and the basal ganglia) showed significant individual variation in change during the second follow-up. No individual variability was noted in the change of orbital frontal and visual cortices. In two white matter regions, we were able to identify factors associated with individual differences in brain shrinkage. In corpus callosum, shrinkage rate was greater in persons with hypertension, and in the pons, women and carriers of the ApoEepsilon4 allele exhibited declines not noted in the whole sample.

  7. Competition of Dynamic Self-Confidence and Inhomogeneous Individual Influence in Voter Models

    Directory of Open Access Journals (Sweden)

    Fei Xiong

    2013-12-01

    Full Text Available In social systems, agents often have different ability to persuade neighbors to adopt their opinions. In this paper, we aim to investigate how the location and heterogeneity of influencers in social networks can improve convergence. We propose a voter model with dynamic self-conviction and heterogeneous individual influence which is related to the underlying network topology. An agent may keep its current opinion according to personal conviction, or otherwise, it may preferentially choose the opinion of the neighbor that has a great influence. Individual conviction evolves during the dynamic process, and can be strengthened by social recognition. Simulations indicate our model has three nontrivial results. First, the conservation of average magnetization in the voter model is broken under the effect of individual conviction and influence, and the system evolves to an ordered state in which one opinion is dominant, but total consensus is prevented by extremists. Furthermore, individual influence has a subtle action on opinion evolution. The heterogeneity of individual influence accelerates the relaxation process, but, with the action of dynamic conviction, more heterogeneous influence does not mean the average magnetization will be more ordered. In addition, when competing with agents’ conviction, more heterogeneous individual influence plays a more significant role in agents’ decisions. These results are helpful for understanding some aspects of collective phenomena that occur on online social media.

  8. 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.

  9. 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.

  10. Antecedents of emotion knowledge: Predictors of individual differences in young children

    OpenAIRE

    Bennett, David S.; Bendersky, Margaret; Lewis, Michael

    2005-01-01

    Individual differences in emotion knowledge were examined among 188 4-year-old, predominantly African American children. Cognitive ability and negative emotionality, maternal characteristics (parenting, verbal intelligence, and depressive symptoms), environmental risk, and child sex were examined as predictors of emotion knowledge. Regression analyses indicated that cognitively skilled children who resided in relatively low risk environments with verbally intelligent mothers possessed greater...

  11. Multimedia Learning and Individual Differences: Mediating the Effects of Working Memory Capacity with Segmentation

    Science.gov (United States)

    Lusk, Danielle L.; Evans, Amber D.; Jeffrey, Thomas R.; Palmer, Keith R.; Wikstrom, Chris S.; Doolittle, Peter E.

    2009-01-01

    Research in multimedia learning lacks an emphasis on individual difference variables, such as working memory capacity (WMC). The effects of WMC and the segmentation of multimedia instruction were examined by assessing the recall and application of low (n = 66) and high (n = 67) working memory capacity students randomly assigned to either a…

  12. 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…

  13. What Textbooks Tell Prospective Teachers about Individual Differences and Exceptional Students: Two Divergent Views.

    Science.gov (United States)

    Wilson, Barry; Buss, Ray

    Forty-eight textbooks in educational psychology published after 1950 were located for review. Half the books were published before 1975 and half following 1975. The purpose of the study was to describe changes in coverage and treatment of individual differences and special populations since the passage of Public Law 94-142 (the Education for All…

  14. 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

  15. Prefered time headway in car-following and individual differences in perceptual-motor skills

    NARCIS (Netherlands)

    Winsum, W. van

    1999-01-01

    18 Subjects were tested in a simulator to assess whether choice of time headway in car-following is related to individual differences in perceptual-motor skills. Drivers with a larger preferred time headway committed larger steering errors while driving on a winding road and were less accurate in

  16. Preferred time headway in car-following and individual differences in perceptual-motor skills

    NARCIS (Netherlands)

    van Winsum, W

    1998-01-01

    18 subjects were tested in a simulator to assess whether choice of time headway in car-following is related to individual differences in perceptual-motor skills. Drivers with a larger preferred time headway committed larger steering errors while driving on a winding road and were less accurate in

  17. Distrust As a Disease Avoidance Strategy: Individual Differences in Disgust Sensitivity Regulate Generalized Social Trust

    DEFF Research Database (Denmark)

    Aarøe, Lene; Osmundsen, Mathias; Petersen, Michael Bang

    2016-01-01

    that these motivations should prompt people to avoid others more broadly. Empirically, we utilize two convenience samples and a large nationally representative sample of US citizens to demonstrate the existence of a robust and replicable effect of individual differences in pathogen disgust sensitivity on generalized...

  18. A Strategy of Professional Development for Dealing with Individual Differences in the Classroom.

    Science.gov (United States)

    Kremer-Hayon, Lya; Ben-Peretz, Miriam

    1985-01-01

    This article relates to two problems: how to deal with individual differences in heterogeneous classes and how to plan and implement professional development programs in this area. The planning and implementation of such a program through a process of collaboration between researchers and teachers is reported in the study. (Author)

  19. Individual differences in the effect of daily stressors on psoriasis: a prospective study.

    NARCIS (Netherlands)

    Verhoeven, E.W.M.; Kraaimaat, F.W.; Jong, E.M.G.J. de; Schalkwijk, J.; Kerkhof, P.C.M. van de; Evers, A.W.M.

    2009-01-01

    BACKGROUND: There is increasing evidence that stressors contribute to the severity of chronic inflammatory diseases such as psoriasis. However, much less is known about possible individual differences between patients in their stress reactivity, particularly the role of cognitive and behavioural fac

  20. Task Complexity, Focus on L2 Constructions, and Individual Differences: A Classroom-Based Study

    Science.gov (United States)

    Revesz, Andrea

    2011-01-01

    Motivated by cognitive-interactionist frameworks for task-based learning, this study explores whether task complexity affects the extent to which learners focus on form-meaning connections during task-based work in a classroom setting, and whether this relationship is modulated by 3 individual difference factors--linguistic self-confidence,…