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Sample records for underlying individual differences

  1. Individual differences in performance under acute stress

    NARCIS (Netherlands)

    Delahaij, R.; Gaillard, A.W.K.

    2008-01-01

    To be able to predict which persons are capable to perform under acute stress is important for the selection and training of professionals in the military, police, and fire- fighting domain. The present study examines how individual differences in coping (style, efficacy, and behavior) explain

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

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    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.

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

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    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.

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

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    Heatherton, Todd F.

    2015-01-01

    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. PMID:24795440

  5. The Influence of Individual Variability on Zooplankton Population Dynamics under Different Environmental Conditions

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    Bi, R.; Liu, H.

    2016-02-01

    Understanding how biological components respond to environmental changes could be insightful to predict ecosystem trajectories under different climate scenarios. Zooplankton are key components of marine ecosystems and changes in their dynamics could have major impact on ecosystem structure. We developed an individual-based model of a common coastal calanoid copepod Acartia tonsa to examine how environmental factors affect zooplankton population dynamics and explore the role of individual variability in sustaining population under various environmental conditions consisting of temperature, food concentration and salinity. Total abundance, egg production and proportion of survival were used to measure population success. Results suggested population benefits from high level of individual variability under extreme environmental conditions including unfavorable temperature, salinity, as well as low food concentration, and selection on fast-growers becomes stronger with increasing individual variability and increasing environmental stress. Multiple regression analysis showed that temperature, food concentration, salinity and individual variability have significant effects on survival of A. tonsa population. These results suggest that environmental factors have great influence on zooplankton population, and individual variability has important implications for population survivability under unfavorable conditions. Given that marine ecosystems are at risk from drastic environmental changes, understanding how individual variability sustains populations could increase our capability to predict population dynamics in a changing environment.

  6. Individual differences in delay discounting under acute stress: the role of trait perceived stress

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    Karolina M. Lempert

    2012-07-01

    Full Text Available Delay discounting refers to the reduction of the value of a future reward as the delay to that reward increases. The rate at which individuals discount future rewards varies as a function of both individual and contextual differences, and high delay discounting rates have been linked with problematic behaviors, including drug abuse and gambling. The current study investigated the effects of acute anticipatory stress on delay discounting, while considering two important factors: individual perceptions of stress and whether the stressful situation is future-focused or present-focused. Half of the participants experienced acute stress by anticipating giving a videotaped speech. This stress was either future-oriented (speech about future job or present-oriented (speech about physical appearance. They then performed a delay discounting task, in which they chose between smaller, immediate rewards and larger, delayed rewards. Their scores on the Perceived Stress Scale were also collected. The way in which one appraises a stressful situation interacts with acute stress to influence choices; under stressful conditions, delay discounting rate was highest in individuals with low perceived stress and lowest for individuals with high perceived stress. This result might be related to individual variation in reward responsiveness under stress. Furthermore, the time orientation of the task interacted with its stressfulness to affect the individual’s propensity to choose immediate rewards. These findings add to our understanding of the intermediary factors between stress and decision making.

  7. Flexibility of Physiological Traits Underlying Inter-Individual Growth Differences in Intertidal and Subtidal Mussels Mytilusgalloprovincialis.

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    María José Fernández-Reiriz

    Full Text Available Mussel seed (Mytilusgalloprovincialis gathered from the intertidal and subtidal environments of a Galician embayment (NW, Spain were maintained in the laboratory during five months to select fast (F and slow (S growing mussels. The physiological basis underlying inter-individual growth variations were compared for F and S mussels from both origins. Fast growing seemed to be a consequence of greater energy intake (20% higher clearance and ingestion rate and higher food absorption rate coupled with low metabolic costs. The enhanced energy absorption (around 65% higher resulted in 3 times higher Scope for Growth in F mussels (20.5±4.9 J h(-1 than S individuals (7.3±1.1 J h(-1. The higher clearance rate of F mussels appears to be linked with larger gill filtration surface compared to S mussels. Intertidal mussels showed higher food acquisition and absorption per mg of organic weight (i.e. mass-specific standardization than subtidal mussels under the optimal feeding conditions of the laboratory. However, the enhanced feeding and digestive rates were not enough to compensate for the initial differences in tissue weight between mussels of similar shell length collected from the intertidal and subtidal environments. At the end of the experiment, subtidal individuals had higher gill efficiency, which probably lead to higher total feeding and absorption rates relative to intertidal individuals.

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

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    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.

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

    NARCIS (Netherlands)

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

    2012-01-01

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

  10. Sex and HIV serostatus differences in decision making under risk among substance-dependent individuals.

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    Martin, Eileen; Gonzalez, Raul; Vassileva, Jasmin; Maki, Pauline M; Bechara, Antoine; Brand, Matthias

    2016-01-01

    HIV+ individuals with and without substance use disorders make significantly poorer decisions when information about the probability and magnitude of wins and losses is not available. We administered the Game of Dice Task, a measure of decision making under risk that provides this information explicitly, to 92 HIV+ and 134 HIV- substance-dependent men and women. HIV+ participants made significantly poorer decisions than HIV- participants, but this deficit appeared more prominent among HIV+ women. These data indicate that decision making under risk is impaired among HIV+ substance-dependent individuals (SDIs). Potential factors for the HIV+ women's relatively greater impairment are discussed.

  11. Some factors underlying individual differences in speech recognition on PRESTO: a first report.

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    Tamati, Terrin N; Gilbert, Jaimie L; Pisoni, David B

    2013-01-01

    Previous studies investigating speech recognition in adverse listening conditions have found extensive variability among individual listeners. However, little is currently known about the core underlying factors that influence speech recognition abilities. To investigate sensory, perceptual, and neurocognitive differences between good and poor listeners on the Perceptually Robust English Sentence Test Open-set (PRESTO), a new high-variability sentence recognition test under adverse listening conditions. Participants who fell in the upper quartile (HiPRESTO listeners) or lower quartile (LoPRESTO listeners) on key word recognition on sentences from PRESTO in multitalker babble completed a battery of behavioral tasks and self-report questionnaires designed to investigate real-world hearing difficulties, indexical processing skills, and neurocognitive abilities. Young, normal-hearing adults (N = 40) from the Indiana University community participated in the current study. Participants' assessment of their own real-world hearing difficulties was measured with a self-report questionnaire on situational hearing and hearing health history. Indexical processing skills were assessed using a talker discrimination task, a gender discrimination task, and a forced-choice regional dialect categorization task. Neurocognitive abilities were measured with the Auditory Digit Span Forward (verbal short-term memory) and Digit Span Backward (verbal working memory) tests, the Stroop Color and Word Test (attention/inhibition), the WordFam word familiarity test (vocabulary size), the Behavioral Rating Inventory of Executive Function-Adult Version (BRIEF-A) self-report questionnaire on executive function, and two performance subtests of the Wechsler Abbreviated Scale of Intelligence (WASI) Performance Intelligence Quotient (IQ; nonverbal intelligence). Scores on self-report questionnaires and behavioral tasks were tallied and analyzed by listener group (HiPRESTO and LoPRESTO). The extreme

  12. Auditory and Cognitive Factors Underlying Individual Differences in Aided Speech-Understanding among Older Adults

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    Larry E. Humes

    2013-10-01

    Full Text Available This study was designed to address individual differences in aided speech understanding among a relatively large group of older adults. The group of older adults consisted of 98 adults (50 female and 48 male ranging in age from 60 to 86 (mean = 69.2. Hearing loss was typical for this age group and about 90% had not worn hearing aids. All subjects completed a battery of tests, including cognitive (6 measures, psychophysical (17 measures, and speech-understanding (9 measures, as well as the Speech, Spatial and Qualities of Hearing (SSQ self-report scale. Most of the speech-understanding measures made use of competing speech and the non-speech psychophysical measures were designed to tap phenomena thought to be relevant for the perception of speech in competing speech (e.g., stream segregation, modulation-detection interference. All measures of speech understanding were administered with spectral shaping applied to the speech stimuli to fully restore audibility through at least 4000 Hz. The measures used were demonstrated to be reliable in older adults and, when compared to a reference group of 28 young normal-hearing adults, age-group differences were observed on many of the measures. Principal-components factor analysis was applied successfully to reduce the number of independent and dependent (speech understanding measures for a multiple-regression analysis. Doing so yielded one global cognitive-processing factor and five non-speech psychoacoustic factors (hearing loss, dichotic signal detection, multi-burst masking, stream segregation, and modulation detection as potential predictors. To this set of six potential predictor variables were added subject age, Environmental Sound Identification (ESI, and performance on the text-recognition-threshold (TRT task (a visual analog of interrupted speech recognition. These variables were used to successfully predict one global aided speech-understanding factor, accounting for about 60% of the variance.

  13. Individual differences in context-dependent effects reveal common mechanisms underlying the direction aftereffect and direction repulsion.

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    McGovern, David P; Walsh, Kevin S; Bell, Jason; Newell, Fiona N

    2017-12-01

    Both spatial and temporal context influence our perception of visual stimuli. For instance, both nearby moving stimuli and recently viewed motion can lead to biases in the perceived direction of a moving stimulus. Due to similarities in the spatial tuning properties of these spatial and temporal context-dependent effects, it is often assumed that they share a functional goal in motion processing and arise from common neural mechanisms. However, the psychophysical evidence concerning this assumption is inconsistent. Here we used an individual differences approach to examine the relationship between different effects of contextual modulation on perception. We reasoned that if measures of contextual modulation share a common underlying mechanism, they should exhibit a strong positive correlation across participants. To test this hypothesis, estimates of the direction aftereffect, direction repulsion, the tilt aftereffect and contrast adaptation were obtained from 54 healthy participants. Our results show pronounced interindividual differences in the effect sizes of all four tasks. Furthermore, there was a strong positive correlation between the estimates of the direction aftereffect and direction repulsion. This correlation was also evident in the threshold elevations that accompanied these repulsive biases in perceived direction. While the effects of contrast adaptation did not correlate with any of the other tasks, there was a weak, but non-significant, correlation between the direction and tilt aftereffects. These results provide evidence for common mechanisms underlying the direction aftereffect and direction repulsion. Copyright © 2016 Elsevier Ltd. All rights reserved.

  14. Genomic instability after targeted irradiation of human lymphocytes: Evidence for inter-individual differences under bystander conditions

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    Kadhim, Munira A., E-mail: mkadhim@brookes.ac.uk [School of Life Sciences, Oxford Brookes University, Oxford OX3 0BP (United Kingdom); Lee, Ryonfa [Biophysics, GSI Helmholtzzentrum fuer Schwerionenforschung GmbH, Planckstrasse 1, D-64291 Darmstadt (Germany); Moore, Stephen R.; Macdonald, Denise A. [Radiation and Genome Stability Unit, Medical Research Council, Harwell, Oxfordshire OX11 0RD (United Kingdom); Chapman, Kim L. [School of Life Sciences, Oxford Brookes University, Oxford OX3 0BP (United Kingdom); Patel, Gaurang; Prise, Kevin M. [Centre for Cancer Research and Cell Biology, Queen' s University Belfast, Belfast BT9 7BL (United Kingdom)

    2010-06-01

    Environmental {sup 222}radon exposure is a human health concern, and many studies demonstrate that very low doses of high LET {alpha}-particle irradiation initiate deleterious genetic consequences in both irradiated and non-irradiated bystander cells. One consequence, radiation-induced genomic instability (RIGI), is a hallmark of tumorigenesis and is often assessed by measuring delayed chromosomal aberrations. We utilised a technique that facilitates transient immobilization of primary lymphocytes for targeted microbeam irradiation and have reported that environmentally relevant doses, e.g. a single {sup 3}He{sup 2+} particle traversal to a single cell, are sufficient to induce RIGI. Herein we sought to determine differences in radiation response in lymphocytes isolated from five healthy male donors. Primary lymphocytes were irradiated with a single particle per cell nucleus. We found evidence for inter-individual variation in radiation response (RIGI, measured as delayed chromosome aberrations). Although this was not highly significant, it was possibly masked by high levels of intra-individual variation. While there are many studies showing a link between genetic predisposition and RIGI, there are few studies linking genetic background with bystander effects in normal human lymphocytes. In an attempt to investigate inter-individual variation in the induction of bystander effects, primary lymphocytes were irradiated with a single particle under conditions where fractions of the population were traversed. We showed a marked genotype-dependent bystander response in one donor after exposure to 15% of the population. The findings may also be regarded as a radiation-induced genotype-dependent bystander effect triggering an instability phenotype.

  15. Untangling the neurobiology of coping styles in rodents : Towards neural mechanisms underlying individual differences in disease susceptibility

    NARCIS (Netherlands)

    de Boer, Sietse F; Buwalda, Bauke; Koolhaas, Jaap M.

    Considerable individual differences exist in trait-like patterns of behavioral and physiological responses to salient environmental challenges. This individual variation in stress coping styles has an important functional role in terms of health and fitness. Hence, understanding the neural embedding

  16. Relationships between individual behaviour and morphometry under different experimental conditions of temperature and feeding in glass eels (Anguilla anguilla

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    A. Bardonnet

    2008-01-01

    Full Text Available After Anguilla anguilla larvae reach the European coast, metamorphosing glass eels exhibit an estuarine migration phase and can potentially colonize the continental area. Associated behaviours to upstream movement in estuary and river basin differ strongly: passive tidal transport in estuary, active swimming beyond the upstream tidal limit. Moreover, the migratory behaviour may shift towards a density-dependent dispersal beyond this limit. A positive relationship has previously been established between glass eels’ body condition and migratory behaviour in estuary and also higher in the river basin. An experiment was settled to test for the density-dependent versus migratory behaviour under controlled conditions. The relationships between some behaviours (swimming, grouping, feeding, and aggressiveness and body condition was investigated at the individual level. Two controlled factors were crossed, leading to four combinations of high and low levels of food and temperature. The high level of food led to a lesser loss in body condition. Swimming activity was positively related to initial body condition and loss in body condition, but these two variables were not related to aggressiveness. We conclude that the density-dependent dispersal hypothesis was not reinforced by these present results.

  17. Relationships between individual behaviour and morphometry under different experimental conditions of temperature and feeding in glass eels (Anguilla anguilla

    Directory of Open Access Journals (Sweden)

    Bardonnet A.

    2009-02-01

    Full Text Available After Anguilla anguilla larvae reach the European coast, metamorphosing glass eels exhibit an estuarine migration phase and can potentially colonize the continental area. Associated behaviours to upstream movement in estuary and river basin differ strongly: passive tidal transport in estuary, active swimming beyond the upstream tidal limit. Moreover, the migratory behaviour may shift towards a density-dependent dispersal beyond this limit. A positive relationship has previously been established between glass eels’ body condition and migratory behaviour in estuary and also higher in the river basin. An experiment was settled to test for the density-dependent versus migratory behaviour under controlled conditions. The relationships between some behaviours (swimming, grouping, feeding, and aggressiveness and body condition was investigated at the individual level. Two controlled factors were crossed, leading to four combinations of high and low levels of food and temperature. The high level of food led to a lesser loss in body condition. Swimming activity was positively related to initial body condition and loss in body condition, but these two variables were not related to aggressiveness. We conclude that the density-dependent dispersal hypothesis was not reinforced by these present results.

  18. Extrapunitive and intropunitive individuals activate different parts of the prefrontal cortex under an ego-blocking frustration.

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

    2014-01-01

    Different people make different responses when they face a frustrating situation: some punish others (extrapunitive), while others punish themselves (intropunitive). Few studies have investigated the neural structures that differentiate extrapunitive and intropunitive individuals. The present fMRI study explored these neural structures using two different frustrating situations: an ego-blocking situation which blocks a desire or goal, and a superego-blocking situation which blocks self-esteem. In the ego-blocking condition, the extrapunitive group (n = 9) showed greater activation in the bilateral ventrolateral prefrontal cortex, indicating that these individuals prefer emotional processing. On the other hand, the intropunitive group (n = 9) showed greater activation in the left dorsolateral prefrontal cortex, possibly reflecting an effortful control for anger reduction. Such patterns were not observed in the superego-blocking condition. These results indicate that the prefrontal cortex is the source of individual differences in aggression direction in the ego-blocking situation.

  19. Extrapunitive and intropunitive individuals activate different parts of the prefrontal cortex under an ego-blocking frustration.

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    Takehiro Minamoto

    Full Text Available Different people make different responses when they face a frustrating situation: some punish others (extrapunitive, while others punish themselves (intropunitive. Few studies have investigated the neural structures that differentiate extrapunitive and intropunitive individuals. The present fMRI study explored these neural structures using two different frustrating situations: an ego-blocking situation which blocks a desire or goal, and a superego-blocking situation which blocks self-esteem. In the ego-blocking condition, the extrapunitive group (n = 9 showed greater activation in the bilateral ventrolateral prefrontal cortex, indicating that these individuals prefer emotional processing. On the other hand, the intropunitive group (n = 9 showed greater activation in the left dorsolateral prefrontal cortex, possibly reflecting an effortful control for anger reduction. Such patterns were not observed in the superego-blocking condition. These results indicate that the prefrontal cortex is the source of individual differences in aggression direction in the ego-blocking situation.

  20. Extrapunitive and Intropunitive Individuals Activate Different Parts of the Prefrontal Cortex under an Ego-Blocking Frustration

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

    2014-01-01

    Different people make different responses when they face a frustrating situation: some punish others (extrapunitive), while others punish themselves (intropunitive). Few studies have investigated the neural structures that differentiate extrapunitive and intropunitive individuals. The present fMRI study explored these neural structures using two different frustrating situations: an ego-blocking situation which blocks a desire or goal, and a superego-blocking situation which blocks self-esteem. In the ego-blocking condition, the extrapunitive group (n = 9) showed greater activation in the bilateral ventrolateral prefrontal cortex, indicating that these individuals prefer emotional processing. On the other hand, the intropunitive group (n = 9) showed greater activation in the left dorsolateral prefrontal cortex, possibly reflecting an effortful control for anger reduction. Such patterns were not observed in the superego-blocking condition. These results indicate that the prefrontal cortex is the source of individual differences in aggression direction in the ego-blocking situation. PMID:24454951

  1. Untangling the neurobiology of coping styles in rodents: Towards neural mechanisms underlying individual differences in disease susceptibility.

    Science.gov (United States)

    de Boer, Sietse F; Buwalda, Bauke; Koolhaas, Jaap M

    2017-03-01

    Considerable individual differences exist in trait-like patterns of behavioral and physiological responses to salient environmental challenges. This individual variation in stress coping styles has an important functional role in terms of health and fitness. Hence, understanding the neural embedding of coping style variation is fundamental for biobehavioral neurosciences in probing individual disease susceptibility. This review outlines individual differences in trait-aggressiveness as an adaptive component of the natural sociobiology of rats and mice, and highlights that these reflect the general style of coping that varies from proactive (aggressive) to reactive (docile). We propose that this qualitative coping style can be disentangled into multiple quantitative behavioral domains, e.g., flexibility/impulse control, emotional reactivity and harm avoidance/reward processing, that each are encoded into selective neural circuitries. Since functioning of all these brain circuitries rely on fine-tuned serotonin signaling, autoinhibitory control mechanisms of serotonergic neuron (re)activity are crucial in orchestrating general coping style. Untangling the precise neuromolecular mechanisms of different coping styles will provide a roadmap for developing better therapeutic strategies of stress-related diseases. Copyright © 2016 Elsevier Ltd. All rights reserved.

  2. Correlated individual differences suggest a common mechanism underlying metacognition in visual perception and visual short-term memory.

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    Samaha, Jason; Postle, Bradley R

    2017-11-29

    Adaptive behaviour depends on the ability to introspect accurately about one's own performance. Whether this metacognitive ability is supported by the same mechanisms across different tasks is unclear. We investigated the relationship between metacognition of visual perception and metacognition of visual short-term memory (VSTM). Experiments 1 and 2 required subjects to estimate the perceived or remembered orientation of a grating stimulus and rate their confidence. We observed strong positive correlations between individual differences in metacognitive accuracy between the two tasks. This relationship was not accounted for by individual differences in task performance or average confidence, and was present across two different metrics of metacognition and in both experiments. A model-based analysis of data from a third experiment showed that a cross-domain correlation only emerged when both tasks shared the same task-relevant stimulus feature. That is, metacognition for perception and VSTM were correlated when both tasks required orientation judgements, but not when the perceptual task was switched to require contrast judgements. In contrast with previous results comparing perception and long-term memory, which have largely provided evidence for domain-specific metacognitive processes, the current findings suggest that metacognition of visual perception and VSTM is supported by a domain-general metacognitive architecture, but only when both domains share the same task-relevant stimulus feature. © 2017 The Author(s).

  3. Stress and success: individual differences in the glucocorticoid stress response predict behavior and reproductive success under high predation risk.

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    Vitousek, Maren N; Jenkins, Brittany R; Safran, Rebecca J

    2014-11-01

    A fundamental element of how vertebrates respond to stressors is by rapidly elevating circulating glucocorticoid hormones. Individual variation in the magnitude of the glucocorticoid stress response has been linked with reproductive success and survival. But while the adaptive value of this response is believed to stem in part from changes in the expression of hormone-mediated behaviors, it is not clear how the behavior of stronger and weaker glucocorticoid responders differs during reproduction, or during exposure to ecologically relevant stressors. Here we report that in a population of barn swallows (Hirundo rustica erythrogaster) experiencing high rates of nest predation, circulating levels of corticosterone (the primary avian glucocorticoid) during exposure to a standardized stressor predict aspects of subsequent behavior and fitness. Individuals that mounted a stronger corticosterone stress response during the early reproductive period did not differ in clutch size, but fledged fewer offspring. Parents with higher stress-induced corticosterone during the early reproductive period later provisioned their nestlings at lower rates. Additionally, in the presence of a model predator stress-induced corticosterone was positively associated with the latency to return to the nest, but only among birds that were observed to return. Model comparisons revealed that stress-induced hormones were better predictors of the behavioral and fitness effects of exposure to transient, ecologically relevant stressors than baseline corticosterone. These findings are consistent with functional links between individual variation in the hormonal and behavioral response to stressors. If such links occur, then selection on the heritable components of the corticosterone stress response could promote adaptation to novel environments or predation regimes. Copyright © 2014 Elsevier Inc. All rights reserved.

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

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    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. Copyright © 2015 Elsevier Ltd. All rights reserved.

  5. Being born under adverse economic conditions leads to a higher cardiovascular mortality rate later in life: evidence based on individuals born at different stages of the business cycle.

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    van den Berg, Gerard J; Doblhammer-Reiter, Gabriele; Christensen, Kaare

    2011-05-01

    We connect the recent medical and economic literatures on the long-run effects of early-life conditions by analyzing the effects of economic conditions on the individual cardiovascular (CV) mortality rate later in life, using individual data records from the Danish Twin Registry covering births since the 1870s and including the cause of death. To capture exogenous variation of conditions early in life, we use the state of the business cycle around birth. We find significant negative effects of economic conditions around birth on the individual CV mortality rate at higher ages. There is no effect on the cancer-specific mortality rate. From variation within and between monozygotic and dizygotic twin pairs born under different conditions, we conclude that the fate of an individual is more strongly determined by genetic and household-environmental factors if early-life conditions are poor. Individual-specific qualities come more to fruition if the starting position in life is better.

  6. Individual differences in behavioural plasticities.

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    Stamps, Judy A

    2016-05-01

    Interest in individual differences in animal behavioural plasticities has surged in recent years, but research in this area has been hampered by semantic confusion as different investigators use the same terms (e.g. plasticity, flexibility, responsiveness) to refer to different phenomena. The first goal of this review is to suggest a framework for categorizing the many different types of behavioural plasticities, describe examples of each, and indicate why using reversibility as a criterion for categorizing behavioural plasticities is problematic. This framework is then used to address a number of timely questions about individual differences in behavioural plasticities. One set of questions concerns the experimental designs that can be used to study individual differences in various types of behavioural plasticities. Although within-individual designs are the default option for empirical studies of many types of behavioural plasticities, in some situations (e.g. when experience at an early age affects the behaviour expressed at subsequent ages), 'replicate individual' designs can provide useful insights into individual differences in behavioural plasticities. To date, researchers using within-individual and replicate individual designs have documented individual differences in all of the major categories of behavioural plasticities described herein. Another important question is whether and how different types of behavioural plasticities are related to one another. Currently there is empirical evidence that many behavioural plasticities [e.g. contextual plasticity, learning rates, IIV (intra-individual variability), endogenous plasticities, ontogenetic plasticities) can themselves vary as a function of experiences earlier in life, that is, many types of behavioural plasticity are themselves developmentally plastic. These findings support the assumption that differences among individuals in prior experiences may contribute to individual differences in behavioural

  7. 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.

  8. 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?

  9. Individual Differences in Interacting With Hypermedia Manuals

    National Research Council Canada - National Science Library

    Hegarty, Mary

    2003-01-01

    We examined individual differences in interacting and learning from diagrams, multimedia presentations and hypermedia instructional manuals and how these-individual differences related to spatial abilities and knowledge...

  10. Sensorimotor Learning: Neurocognitive Mechanisms and Individual Differences.

    Science.gov (United States)

    Seidler, R D; Carson, R G

    2017-07-13

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

  11. Diabetes in rural individuals of different nutritional status and the alarming situation demands focus more on its under-nutrition association.

    Science.gov (United States)

    Maiti, Smarajit; Sinha, Nirmalya K; Khan, Md Mobidullah; Das, Prasanta K; Chattopadhyay, Jadab C

    2015-02-01

    To study the relationship of nutritional-status with diabetes. The socioeconomics/anthropometrics, blood-glucose/systemic-hypertension are evaluated in consecutively-selected diabetic-patients. Semi-urban/rural India. Hyperglycaemic patients (total 90/male 37). Blood-glucose (PP-mean ± SE) in individuals is overweight - 38.89% (226.94 ± 9.59), normal-weight - 50% (217.58 ± 1.34), underweight - 11.11% (305.50 ± 21.35) indicating most hyperglycaemia in undernourished-group (F = 6.357, p group occupies higher glucose-groups in ≤140, 141-270, and ≥270 mg/dL. The blood-glucose negatively correlates with waist(r = -0.282; p group (χ(2 )= 12.86; p group of 141-270 mg/dL glucose has 45% and rest groups together have 23% hypertensive individuals relating directly, hypertension and diabetic-onset. Diabetes, explored in group and even more in female should be extensively studied accounting WHO categorization (1985/TRS/727) of malnutrition related diabetes (MRDM). Further, different interactive risk-factors should be properly addressed and the global-malnutrition/gender-based inequities be eradicated.

  12. Neural dynamics underlying emotional transmissions between individuals

    OpenAIRE

    Golland, Yulia; Levit-Binnun, Nava; Hendler, Talma; Lerner, Yulia

    2017-01-01

    Abstract Emotional experiences are frequently shaped by the emotional responses of co-present others. Research has shown that people constantly monitor and adapt to the incoming social–emotional signals, even without face-to-face interaction. And yet, the neural processes underlying such emotional transmissions have not been directly studied. Here, we investigated how the human brain processes emotional cues which arrive from another, co-attending individual. We presented continuous emotional...

  13. Individual differences in visual perception and memory

    NARCIS (Netherlands)

    Colizoli, O.

    2014-01-01

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

  14. Individual Differences in Susceptibility to Inattentional Blindness

    Science.gov (United States)

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

    2011-01-01

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

  15. Being born under adverse economic conditions leads to a higher cardiovascular mortality rate later in life: evidence based on individuals born at different stages of the business cycle

    DEFF Research Database (Denmark)

    van den Berg, Gerard J; Doblhammer-Reiter, Gabriele; Christensen, Kaare

    2011-01-01

    since the 1870s and including the cause of death. To capture exogenous variation of conditions early in life, we use the state of the business cycle around birth. We find significant negative effects of economic conditions around birth on the individual CV mortality rate at higher ages...

  16. Neural dynamics underlying emotional transmissions between individuals.

    Science.gov (United States)

    Golland, Yulia; Levit-Binnun, Nava; Hendler, Talma; Lerner, Yulia

    2017-08-01

    Emotional experiences are frequently shaped by the emotional responses of co-present others. Research has shown that people constantly monitor and adapt to the incoming social-emotional signals, even without face-to-face interaction. And yet, the neural processes underlying such emotional transmissions have not been directly studied. Here, we investigated how the human brain processes emotional cues which arrive from another, co-attending individual. We presented continuous emotional feedback to participants who viewed a movie in the scanner. Participants in the social group (but not in the control group) believed that the feedback was coming from another person who was co-viewing the same movie. We found that social-emotional feedback significantly affected the neural dynamics both in the core affect and in the medial pre-frontal regions. Specifically, the response time-courses in those regions exhibited increased similarity across recipients and increased neural alignment with the timeline of the feedback in the social compared with control group. Taken in conjunction with previous research, this study suggests that emotional cues from others shape the neural dynamics across the whole neural continuum of emotional processing in the brain. Moreover, it demonstrates that interpersonal neural alignment can serve as a neural mechanism through which affective information is conveyed between individuals. © The Author (2017). Published by Oxford University Press.

  17. POCP for individual VOC under European conditions

    Energy Technology Data Exchange (ETDEWEB)

    Altenstedt, J.; Pleijel, K.

    1998-09-01

    Ground level ozone has been recognised as one of the most important environmental threats on the regional scale in Europe. Ozone is today considered to be harmful to human health already at the relatively low concentrations present in southern Scandinavia. The fact that ozone has the potential to damage vegetation at these concentrations is already well known. Ozone also gives rise to degradation of materials and is one of the gases which adds to the greenhouse effect. Ground level ozone is formed from nitrogen oxides (NO{sub x}) and volatile organic compounds (VOC) in the presence of sunlight. The only way to reduce ozone is therefore to reduce the emissions of the precursors. Ranking individual VOC by their ozone formation potential can make emission reductions more environmentally efficient and save time and money. POCP values give a ranking of the ozone formation ability of an individual VOC relative to other VOC. A critical analysis of the POCP concept has been performed which shows that the background emissions of NO{sub x} and VOC affect the POCP values to a large extent. Based on the critical analysis, five scenarios with different background emissions of NO{sub x} and VOC were selected for calculation of POCP values. These scenarios were chosen because they reflect the variation in POCP values which arise in different environments within Europe. The range thus indicates POCP values which are intended to be applicable within Europe. POCP values for 83 different VOC are presented in the form of ranges in this report. 42 refs, 13 figs, 3 tabs

  18. 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

  19. Individual differences in fundamental social motives.

    Science.gov (United States)

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

    2016-06-01

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

  20. Quantifying consistent individual differences in habitat selection.

    Science.gov (United States)

    Leclerc, Martin; Vander Wal, Eric; Zedrosser, Andreas; Swenson, Jon E; Kindberg, Jonas; Pelletier, Fanie

    2016-03-01

    Habitat selection is a fundamental behaviour that links individuals to the resources required for survival and reproduction. Although natural selection acts on an individual's phenotype, research on habitat selection often pools inter-individual patterns to provide inferences on the population scale. Here, we expanded a traditional approach of quantifying habitat selection at the individual level to explore the potential for consistent individual differences of habitat selection. We used random coefficients in resource selection functions (RSFs) and repeatability estimates to test for variability in habitat selection. We applied our method to a detailed dataset of GPS relocations of brown bears (Ursus arctos) taken over a period of 6 years, and assessed whether they displayed repeatable individual differences in habitat selection toward two habitat types: bogs and recent timber-harvest cut blocks. In our analyses, we controlled for the availability of habitat, i.e. the functional response in habitat selection. Repeatability estimates of habitat selection toward bogs and cut blocks were 0.304 and 0.420, respectively. Therefore, 30.4 and 42.0 % of the population-scale habitat selection variability for bogs and cut blocks, respectively, was due to differences among individuals, suggesting that consistent individual variation in habitat selection exists in brown bears. Using simulations, we posit that repeatability values of habitat selection are not related to the value and significance of β estimates in RSFs. Although individual differences in habitat selection could be the results of non-exclusive factors, our results illustrate the evolutionary potential of habitat selection.

  1. ERPs reveal individual differences in morphosyntactic processing.

    Science.gov (United States)

    Tanner, Darren; Van Hell, Janet G

    2014-04-01

    We investigated individual differences in the neural substrates of morphosyntactic processing among monolingual English speakers using event-related potentials (ERPs). Although grand-mean analysis showed a biphasic LAN-P600 pattern to grammatical violations, analysis of individuals׳ ERP responses showed that brain responses varied systematically along a continuum between negativity- and positivity-dominant ERP responses across individuals. Moreover, the left hemisphere topography of the negativity resulted from component overlap between a centro-parietal N400 in some individuals and a right hemisphere-dominant P600 in others. Our results show that biphasic ERP waveforms do not always reflect separable processing stages within individuals, and moreover, that the LAN can be a variant of the N400. These results show that there are multiple neurocognitive routes to successful grammatical comprehension in language users across the proficiency spectrum. Our results underscore that understanding and quantifying individual differences can provide an important source of evidence about language processing in the general population. Copyright © 2014 Elsevier Ltd. All rights reserved.

  2. 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

  3. Individual differences in conflict detection during reasoning.

    Science.gov (United States)

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

    2017-04-05

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

  4. 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.

  5. 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…

  6. Are Individual Differences Undertreated in Instructional Design?

    Science.gov (United States)

    Gropper, George L.

    2015-01-01

    Instructional design can be more effective if it is as fixedly dedicated to the accommodation of individual differences as it currently is to the accommodation of subject matters. That is the hypothesis. A menu of accommodation options is provided that is applicable at each of three stages of instructional development or administration: before,…

  7. Proprioception as a basis for individual differences

    OpenAIRE

    Liutsko, Liudmila

    2013-01-01

    In this chapter the author summarises the descriptions of proprioceptive sense from different perspectives. The importance of proprioceptive sense has been shown in developmental psychology, in both the earlier and later stages of individuum formation. The author emphasises in this chapter the role of proprioception as a basis of personality and the individual differences construct. The importance of assessing behaviour at multiple levels has been pointed out by experiments of classic and mod...

  8. Individual differences and the user interface.

    Science.gov (United States)

    VAN DER Veer, Gerrit C

    1989-11-01

    Individual differences in cognitive functions are relevant in introducing novioes to computing. The interaction between the user and the computer may be improved if these psychological characteristics are taken into account in the design of the user interface and in the design of introductory courses. In.section 1 of this paper an analysis is made of individual differences and of the possibilities of adaptation. The user interface is described as an opportunity for adaptation. Methods of adaptation are systematically related to the changeability of individual differences. Illustrated by an overview of previous experimental work, some principles of adaptation are demonstrated in relation to individual differences on variables that are relevant in human-computer interaction. Prior knowledge of mathematics has been shown to be related to success and failure in learning a programming language, and to motivation for using computers. In section 2 ways to prevent the course drop-out rate by structuring the teaching method are illustrated. Strategies of information processing in the user interface, in relation to metacommunication and teaching, are described in section 3 as another example of an individual difference variable that may be attended to in teaching, resulting in reduction of problem solving time. Some cognitive styles are related to success in programming. The choice of adequate educational examples may improve programming habits, as illustrated in section 4. Style of representation and spatial ability are relevant for the development of mental models of computer system. In section 5 some field studies on teaching novices to work with office systems illustrate these relations. Teaching strategies, educational examples, and metaphors, may neutralize the handicap some novices have because of these variables.

  9. Individual Differences in Language Acquisition and Processing.

    Science.gov (United States)

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

    2018-02-01

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

  10. 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.

  11. Hazard personality profiles and individual differences

    International Nuclear Information System (INIS)

    Barnett, J.; Breakwell, G.M.

    1998-01-01

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

  12. Individual differences in multitasking ability and adaptability.

    Science.gov (United States)

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

    2013-08-01

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

  13. Context modulation of facial emotion perception differed by individual difference.

    Science.gov (United States)

    Lee, Tae-Ho; Choi, June-Seek; Cho, Yang Seok

    2012-01-01

    Certain facial configurations are believed to be associated with distinct affective meanings (i.e. basic facial expressions), and such associations are common across cultures (i.e. universality of facial expressions). However, recently, many studies suggest that various types of contextual information, rather than facial configuration itself, are important factor for facial emotion perception. To examine systematically how contextual information influences individuals' facial emotion perception, the present study estimated direct observers' perceptual thresholds for detecting negative facial expressions via a forced-choice psychophysical procedure using faces embedded in various emotional contexts. We additionally measured the individual differences in affective information-processing tendency (BIS/BAS) as a possible factor that may determine the extent to which contextual information on facial emotion perception is used. It was found that contextual information influenced observers' perceptual thresholds for facial emotion. Importantly, individuals' affective-information tendencies modulated the extent to which they incorporated context information into their facial emotion perceptions. The findings of this study suggest that facial emotion perception not only depends on facial configuration, but the context in which the face appears as well. This contextual influence appeared differently with individual's characteristics of information processing. In summary, we conclude that individual character traits, as well as facial configuration and the context in which a face appears, need to be taken into consideration regarding facial emotional perception.

  14. 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.

  15. 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).

  16. Prospective memory, personality, and individual differences.

    Science.gov (United States)

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

    2013-01-01

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

  17. Contexts and Individual Differences as Influences on Consumers' Delay Discounting

    Science.gov (United States)

    Foxall, Gordon R.; Doyle, John R.; Yani-de-Soriano, Mirella; Wells, Victoria K.

    2011-01-01

    Delay discounting is often considered a universal feature of human choice behavior, but there is controversy over whether it is an individual difference that reflects an underlying psychological trait or a domain-specific behavior. Trait influence on discounting would manifest in (a) highly correlated discount rates for all decisions, regardless…

  18. Proprioception as a basis for individual differences

    Directory of Open Access Journals (Sweden)

    Liutsko, Ludmila N.

    2013-09-01

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

  19. Individual differences in spontaneous analogical transfer.

    Science.gov (United States)

    Kubricht, James R; Lu, Hongjing; Holyoak, Keith J

    2017-05-01

    Research on analogical problem solving has shown that people often fail to spontaneously notice the relevance of a semantically remote source analog when solving a target problem, although they are able to form mappings and derive inferences when given a hint to recall the source. Relatively little work has investigated possible individual differences that predict spontaneous transfer, or how such differences may interact with interventions that facilitate transfer. In this study, fluid intelligence was measured for participants in an analogical problem-solving task, using an abridged version of the Raven's Progressive Matrices (RPM) test. In two experiments, we systematically compared the effect of augmenting verbal descriptions of the source with animations or static diagrams. Solution rates to Duncker's radiation problem were measured across varying source presentation conditions, and participants' understanding of the relevant source material was assessed. The pattern of transfer was best fit by a moderated mediation model: the positive impact of fluid intelligence on spontaneous transfer was mediated by its influence on source comprehension; however, this path was in turn modulated by provision of a supplemental animation via its influence on comprehension of the source. Animated source depictions were most beneficial in facilitating spontaneous transfer for those participants with low scores on the fluid intelligence measure.

  20. Individual differences in women's rape avoidance behaviors.

    Science.gov (United States)

    McKibbin, William F; Shackelford, Todd K; Miner, Emily J; Bates, Vincent M; Liddle, James R

    2011-04-01

    Rape can exact severe psychological, physical, and reproductive costs on women, and likely was a recurrent adaptive problem over human evolutionary history. Therefore, women may have evolved psychological mechanisms that motivate rape avoidance behaviors. Guided heuristically by an evolutionary perspective, we tested the hypothesis that women's rape avoidance behaviors would vary with several individual difference variables. Specifically, we predicted that rape avoidance behaviors would covary positively with (1) women's attractiveness, (2) women's involvement in a committed romantic relationship, and (3) the number of family members living nearby. We also predicted that women's rape avoidance behaviors would covary negatively with age. We administered the Rape Avoidance Inventory (McKibbin et al., Pers Indiv Differ 39:336-340, 2009) and a demographic survey to a sample of women (n = 144). The results of correlational and regression analyses were consistent with the predictions, with the exception that women's rape avoidance behaviors did not covary with women's age. Discussion highlighted limitations of the current research and directions for future research on women's rape avoidance psychology and behaviors.

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

    Science.gov (United States)

    Palmer, Stephen E; Griscom, William S

    2013-06-01

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

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

    Science.gov (United States)

    Kim, Kyungil; Markman, Arthur B

    2013-01-01

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

  3. A Bayesian foundation for individual learning under uncertainty

    Directory of Open Access Journals (Sweden)

    Christoph eMathys

    2011-05-01

    Full Text Available Computational learning models are critical for understanding mechanisms of adaptive behavior. However, the two major current frameworks, reinforcement learning (RL and Bayesian learning, both have certain limitations. For example, many Bayesian models are agnostic of inter-individual variability and involve complicated integrals, making online learning difficult. Here, we introduce a generic hierarchical Bayesian framework for individual learning under multiple forms of uncertainty (e.g., environmental volatility and perceptual uncertainty. The model assumes Gaussian random walks of states at all but the first level, with the step size determined by the next higher level. The coupling between levels is controlled by parameters that shape the influence of uncertainty on learning in a subject-specific fashion. Using variational Bayes under a mean field approximation and a novel approximation to the posterior energy function, we derive trial-by-trial update equations which (i are analytical and extremely efficient, enabling real-time learning, (ii have a natural interpretation in terms of RL, and (iii contain parameters representing processes which play a key role in current theories of learning, e.g., precision-weighting of prediction error. These parameters allow for the expression of individual differences in learning and may relate to specific neuromodulatory mechanisms in the brain. Our model is very general: it can deal with both discrete and continuous states and equally accounts for deterministic and probabilistic relations between environmental events and perceptual states (i.e., situations with and without perceptual uncertainty. These properties are illustrated by simulations and analyses of empirical time series. Overall, our framework provides a novel foundation for understanding normal and pathological learning that contextualizes RL within a generic Bayesian scheme and thus connects it to principles of optimality from probability

  4. A bayesian foundation for individual learning under uncertainty.

    Science.gov (United States)

    Mathys, Christoph; Daunizeau, Jean; Friston, Karl J; Stephan, Klaas E

    2011-01-01

    Computational learning models are critical for understanding mechanisms of adaptive behavior. However, the two major current frameworks, reinforcement learning (RL) and Bayesian learning, both have certain limitations. For example, many Bayesian models are agnostic of inter-individual variability and involve complicated integrals, making online learning difficult. Here, we introduce a generic hierarchical Bayesian framework for individual learning under multiple forms of uncertainty (e.g., environmental volatility and perceptual uncertainty). The model assumes Gaussian random walks of states at all but the first level, with the step size determined by the next highest level. The coupling between levels is controlled by parameters that shape the influence of uncertainty on learning in a subject-specific fashion. Using variational Bayes under a mean-field approximation and a novel approximation to the posterior energy function, we derive trial-by-trial update equations which (i) are analytical and extremely efficient, enabling real-time learning, (ii) have a natural interpretation in terms of RL, and (iii) contain parameters representing processes which play a key role in current theories of learning, e.g., precision-weighting of prediction error. These parameters allow for the expression of individual differences in learning and may relate to specific neuromodulatory mechanisms in the brain. Our model is very general: it can deal with both discrete and continuous states and equally accounts for deterministic and probabilistic relations between environmental events and perceptual states (i.e., situations with and without perceptual uncertainty). These properties are illustrated by simulations and analyses of empirical time series. Overall, our framework provides a novel foundation for understanding normal and pathological learning that contextualizes RL within a generic Bayesian scheme and thus connects it to principles of optimality from probability theory.

  5. Procedural Learning and Individual Differences in Language

    Science.gov (United States)

    Lee, Joanna C.; Tomblin, J. Bruce

    2015-01-01

    The aim of the current study was to examine different aspects of procedural memory in young adults who varied with regard to their language abilities. We selected a sample of procedural memory tasks, each of which represented a unique type of procedural learning, and has been linked, at least partially, to the functionality of the corticostriatal…

  6. Fringe consciousness in sequence learning: the influence of individual differences.

    Science.gov (United States)

    Norman, Elisabeth; Price, Mark C; Duff, Simon C

    2006-12-01

    We first describe how the concept of "fringe consciousness" () can characterise gradations of consciousness between the extremes of implicit and explicit learning. We then show that the NEO-PI-R personality measure of openness to feelings, chosen to reflect the ability to introspect on fringe feelings, influences both learning and awareness in the serial reaction time (SRT) task under conditions that have previously been associated with implicit learning (). This provides empirical evidence for the proposed phenomenology and functional role of fringe consciousness in so-called implicit learning paradigms (). Introducing an individual difference variable also helped to identify possible limitations of the exclusion task as a measure of conscious sequence knowledge. Further exploration of individual differences in fringe awareness may help to avoid polarity in the implicit learning debate, and to resolve apparent inconsistencies between previous SRT studies.

  7. Individual differences in cocaine addiction: maladaptive behavioural traits.

    Science.gov (United States)

    Homberg, Judith R; Karel, Peter; Verheij, Michel M M

    2014-07-01

    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 for addiction. As such, both high impulsivity and high anxiety have been reported to predict (compulsive) cocaine self-administration behaviour. Here, we set out a new view explaining how these two behavioural traits may affect addictive behaviour. According to psychological and psychiatric evolutionary views, organisms flourish well when they fit (match) their environment by trait and genotype. However, under non-fit conditions, the need to compensate the failure to deal with this environment increases, and, as a consequence, the functional use of rewarding drugs like cocaine may also increase. It suggests that neither impulsivity nor anxiety are bad per se, but that the increased risk to develop cocaine addiction is dependent on whether behavioural traits are adaptive or maladaptive in the environment to which the animals are exposed. This 'behavioural (mal)adaptation view' on individual differences in vulnerability to cocaine addiction may help to improve therapies for addiction. © 2013 The Authors, Addiction Biology © 2013 Society for the Study of Addiction.

  8. 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.

  9. Measuring individual differences in decision biases: methodological considerations

    Directory of Open Access Journals (Sweden)

    Balazs eAczel

    2015-11-01

    Full Text Available Individual differences in people’s susceptibility to heuristics and biases (HB are often measured by multiple-bias questionnaires consisting of one or a few items for each bias. This research approach relies on the assumptions that (1 different versions of a decision bias task measure are interchangeable as they measure the same cognitive failure; and (2 that some combination of these tasks measures the same underlying construct. Based on these assumptions, in Study 1 we developed two versions of a new decision bias survey for which we modified 13 HB tasks to increase their comparability, construct validity, and the participants’ motivation. The analysis of the responses (N = 1279 showed weak internal consistency within the surveys and a great level of discrepancy between the extracted patterns of the underlying factors. To explore these inconsistencies, in Study 2 we used three original examples of HB tasks for each of seven biases. We created three decision bias surveys by allocating one version of each HB task to each survey. The participants’ responses (N = 527 showed a similar pattern as in Study 1, questioning the assumption that the different examples of the HB tasks are interchangeable and that they measure the same underlying construct. These results emphasize the need to understand the domain-specificity of cognitive biases as well as the effect of the wording of the cover story and the response mode on bias susceptibility before employing them in multiple-bias questionnaires.

  10. Measuring Individual Differences in Decision Biases: Methodological Considerations.

    Science.gov (United States)

    Aczel, Balazs; Bago, Bence; Szollosi, Aba; Foldes, Andrei; Lukacs, Bence

    2015-01-01

    Individual differences in people's susceptibility to heuristics and biases (HB) are often measured by multiple-bias questionnaires consisting of one or a few items for each bias. This research approach relies on the assumptions that (1) different versions of a decision bias task measure are interchangeable as they measure the same cognitive failure; and (2) that some combination of these tasks measures the same underlying construct. Based on these assumptions, in Study 1 we developed two versions of a new decision bias survey for which we modified 13 HB tasks to increase their comparability, construct validity, and the participants' motivation. The analysis of the responses (N = 1279) showed weak internal consistency within the surveys and a great level of discrepancy between the extracted patterns of the underlying factors. To explore these inconsistencies, in Study 2 we used three original examples of HB tasks for each of seven biases. We created three decision bias surveys by allocating one version of each HB task to each survey. The participants' responses (N = 527) showed a similar pattern as in Study 1, questioning the assumption that the different examples of the HB tasks are interchangeable and that they measure the same underlying construct. These results emphasize the need to understand the domain-specificity of cognitive biases as well as the effect of the wording of the cover story and the response mode on bias susceptibility before employing them in multiple-bias questionnaires.

  11. Individual differences affect honest signalling in a songbird

    Science.gov (United States)

    Akçay, Çağlar; Campbell, S. Elizabeth; Beecher, Michael D.

    2014-01-01

    Research in the past decade has established the existence of consistent individual differences or ‘personality’ in animals and their important role in many aspects of animal behaviour. At the same time, research on honest signalling of aggression has revealed that while some of the putative aggression signals are reliable, they are only imperfectly so. This study asks whether a significant portion of the variance in the aggression-signal regression may be explained by individual differences in signalling strategies. Using the well-studied aggressive signalling system of song sparrows (Melospiza melodia), we carried out repeated assays to measure both aggressive behaviours and aggressive signalling of territorial males. Through these assays, we found that aggressive behaviours and aggressive signalling were both highly repeatable, and moreover that aggressive behaviours in 2009–2010 predicted whether the birds would attack a taxidermic mount over a year later. Most significantly, we found that residual variation in signalling behaviours, after controlling for aggressive behaviour, was individually consistent, suggesting there may be a second personality trait determining the level of aggressive signalling. We term this potential personality trait ‘communicativeness’ and discuss these results in the context of honest signalling theories and recent findings reporting prevalence of ‘under-signalling’. PMID:24307671

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

    Science.gov (United States)

    Albrecht, Thorsten; Mattler, Uwe

    2012-09-01

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

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

    NARCIS (Netherlands)

    Zacher, Hannes

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

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

    African Journals Online (AJOL)

    Background: Pain is a protective sensation that alerts an individual to injury from the environment. Experience of pain is characterised by robust individual differences and complex environmental and genetic factors lead to individual variations in pain. Studies of experimental pain are free from the confound of disease ...

  15. 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.

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

    Science.gov (United States)

    Sbarra, David A; Borelli, Jessica L

    2018-03-21

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

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

    NARCIS (Netherlands)

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

    2018-01-01

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

  18. 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…

  19. Influence of culture, family and individual differences on choice of ...

    African Journals Online (AJOL)

    Generally, the family, culture and individual differences made significant joint contribution to the prediction of career choice among the female students. The results from this study suggest the need for career counsellors to design programmes that take into account the family, cultural and individual difference factors that ...

  20. 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…

  1. 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…

  2. Towards a theory of individual differences in statistical learning.

    Science.gov (United States)

    Siegelman, Noam; Bogaerts, Louisa; Christiansen, Morten H; Frost, Ram

    2017-01-05

    In recent years, statistical learning (SL) research has seen a growing interest in tracking individual performance in SL tasks, mainly as a predictor of linguistic abilities. We review studies from this line of research and outline three presuppositions underlying the experimental approach they employ: (i) that SL is a unified theoretical construct; (ii) that current SL tasks are interchangeable, and equally valid for assessing SL ability; and (iii) that performance in the standard forced-choice test in the task is a good proxy of SL ability. We argue that these three critical presuppositions are subject to a number of theoretical and empirical issues. First, SL shows patterns of modality- and informational-specificity, suggesting that SL cannot be treated as a unified construct. Second, different SL tasks may tap into separate sub-components of SL that are not necessarily interchangeable. Third, the commonly used forced-choice tests in most SL tasks are subject to inherent limitations and confounds. As a first step, we offer a methodological approach that explicitly spells out a potential set of different SL dimensions, allowing for better transparency in choosing a specific SL task as a predictor of a given linguistic outcome. We then offer possible methodological solutions for better tracking and measuring SL ability. Taken together, these discussions provide a novel theoretical and methodological approach for assessing individual differences in SL, with clear testable predictions.This article is part of the themed issue 'New frontiers for statistical learning in the cognitive sciences'. © 2016 The Author(s).

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

    NARCIS (Netherlands)

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

    2018-01-01

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

  4. 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.

  5. Brain Activation Underlying Threat Detection to Targets of Different Races

    Science.gov (United States)

    Senholzi, Keith B.; Depue, Brendan E.; Correll, Joshua; Banich, Marie T.; Ito, Tiffany A.

    2016-01-01

    The current study examined blood oxygen level dependent (BOLD) signal underlying racial differences in threat detection. During fMRI, participants determined whether pictures of Black or White individuals held weapons. They were instructed to make shoot responses when the picture showed armed individuals but don’t shoot responses to unarmed individuals, with the cost of not shooting armed individuals being greater than that of shooting unarmed individuals. Participants were faster to shoot armed Blacks than Whites, but faster in making don’t shoot responses to unarmed Whites than Blacks. Brain activity differed to armed versus unarmed targets depending on target race, suggesting different mechanisms underlying threat versus safety decisions. Anterior cingulate cortex was preferentially engaged for unarmed Whites than Blacks. Parietal and visual cortical regions exhibited greater activity for armed Blacks than Whites. Seed-based functional connectivity of the amygdala revealed greater coherence with parietal and visual cortices for armed Blacks than Whites. Furthermore, greater implicit Black-danger associations were associated with increased amygdala activation to armed Blacks, compared to armed Whites. Our results suggest that different neural mechanisms may underlie racial differences in responses to armed versus unarmed targets. PMID:26357911

  6. Modeling of STATCOM under different loading conditions

    DEFF Research Database (Denmark)

    George, G.J.; Ramachandran, Rakesh; Kowsalya, M.

    2012-01-01

    This paper deals with the study and analysis of Flexible AC Transmission Systems (FACTS), mainly the modeling of STATCOM. Reactive Power Compensation plays a very important role in the transmission of Electric Power. A comparative study of how the reactive power is injected into the transmission ...... system with and without STATCOM under different loading condition is also illustrated in this paper. Simulations are performed using MATLAB/SIMULINK software....

  7. 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.

  8. 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.

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

    Science.gov (United States)

    Schwaba, Ted; Bleidorn, Wiebke

    2017-05-16

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

  10. Visualizing Individual Tree Differences in Tree-Ring Studies

    Directory of Open Access Journals (Sweden)

    Mario Trouillier

    2018-04-01

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

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

    Science.gov (United States)

    Stemmler, Gerhard; Wacker, Jan

    2010-07-01

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

  12. 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.

  13. 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…

  14. 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].

  15. Querying metabolism under different physiological constraints.

    Science.gov (United States)

    Cakmak, Ali; Ozsoyoglu, Gultekin; Hanson, Richard W

    2010-04-01

    Metabolism is a representation of the biochemical principles that govern the production, consumption, degradation, and biosynthesis of metabolites in living cells. Organisms respond to changes in their physiological conditions or environmental perturbations (i.e. constraints) via cooperative implementation of such principles. Querying inner working principles of metabolism under different constraints provides invaluable insights for both researchers and educators. In this paper, we propose a metabolism query language (MQL) and discuss its query processing. MQL enables researchers to explore the behavior of the metabolism with a wide-range of predicates including dietary and physiological condition specifications. The query results of MQL are enriched with both textual and visual representations, and its query processing is completely tailored based on the underlying metabolic principles.

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

    DEFF Research Database (Denmark)

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

    2017-01-01

    This study compared salivary bacterial profiles in two groups having a 10-fold difference in levels of caries experience, as it was hypothesized that the composition of the salivary microbiota might associate with the levels of caries experience. Bacterial profiles in stimulated saliva samples from...... 85 individuals with low levels of caries experience (healthy group) and 79 individuals with high levels of caries experience (caries group) were analyzed by means of the Human Oral Microbiome Identification Next Generation Sequencing (HOMINGS) technique. Subsequently, saliva samples from caries......-free individuals in the healthy group (n = 57) and the caries group (n = 31) were compared. A significantly higher α-diversity (p caries group...

  17. 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.

  18. Carriage rates of hepatitis B virus among individuals of different ...

    African Journals Online (AJOL)

    While Hb – AA individuals had the highest rate of 50(5.10%) of carriage, there was no case of infection among individuals with Hb – SS, Hb – SC and Hb –CC. Statistically, Chi Square test showed no significant difference in the rate of hepatitis B infection in relation to haemoglobin genotype (X2= 1.201, P> 0.05).

  19. Wheat genotypes under different seeding rates

    Directory of Open Access Journals (Sweden)

    Luís César Vieira Tavares

    2014-06-01

    Full Text Available The wheat tillering capacity defines yield and yield components, being affected by seeding rate. This study aimed at evaluating wheat genotypes under different seeding rates, in Londrina and Ponta Grossa, Paraná State, Brazil, in 2009 and 2010. A completely randomized blocks design, in a factorial scheme, with four replications, was used. The agronomic traits of three wheat genotypes (PF 014384, BRS Tangará and BRS Pardela were evaluated under the seeding rates of 150 pl m-2, 250 pl m-2, 350 pl m-2 and 450 pl m-2. In Londrina, the maximum yield was observed at densities close to 270 pl m-2, while in Ponta Grossa (2009 there was a linear fit. There was no adjustment for plant height, concerning seeding rate. The number of ears per area (ears m-2 was higher in Ponta Grossa (2009 and did not differ between the locations, in 2010. In Ponta Grossa (2010, the highest one thousand seeds weight was estimated at the density of 341 pl m-2, while in Londrina (2010 it was estimated at 150 pl m-2 and 450 pl m-2. The seeding rate affected grain yield, depending on place and year. In Londrina, there was a limit for yield, concerning seeding rate. The one thousand seeds weight was influenced by seeding rate, depending on year and location. Plant height was affected by genotype and growing area.

  20. Differences Between Individual and Societal Health State Valuations

    Science.gov (United States)

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

    2009-01-01

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

  1. 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.

  2. 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.

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

    Science.gov (United States)

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

    2010-01-01

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

  4. Individual Differences on Job Stress and Related Ill Health

    Directory of Open Access Journals (Sweden)

    Miodraga Stefanovska Petkovska

    2014-03-01

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

  5. 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)…

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

    African Journals Online (AJOL)

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

  7. Developmental and Individual Differences in Pure Numerical Estimation

    Science.gov (United States)

    Booth, Julie L.; Siegler, Robert S.

    2006-01-01

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

  8. 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…

  9. Individual Differences in Psychological Empowerment: A Study of ...

    African Journals Online (AJOL)

    Employee psychological empowerment is acknowledged as critical for organizational effectiveness, yet little research attention has been given to individual differences variables that may enhance or inhibit psychological empowerment. Likewise, although theoretical arguments about the effects of intrinsic motivation and ...

  10. Beyond Individual Differences: Exploring School Effects on SAT Scores

    Science.gov (United States)

    Everson, Howard T.; Millsap, Roger E.

    2004-01-01

    This article explores the complex, hierarchical relation among school characteristics, individual differences in academic achievement, extracurricular activities, and socioeconomic background on performance on the verbal and mathematics Scholastic Aptitude Test (SAT). Using multilevel structural equation models (SEMs) with latent means, we…

  11. Individual Difference Relations in Psychometric and Experimental Cognitive Tasks

    Science.gov (United States)

    1980-04-01

    task Probability Learning Meaningful Learning Fluid Intelligence Crystallized Intelligence Cognitive Complexity scores Stroop -Word-Color (written...Fouinier, Mazzarella, Ricciardi, & Fingeret, 1975) that the Stroop task can provide some information about children’s word recognition skills. Cognitive ...INDIVIDUAL DIFFERENCE RELATIONS IN PSYCHOMETRIC AND EXPERIMENTAL COGNITIVE TASKS John 13. Carroll University of North Carolina at Chapel Hill Final

  12. Responding to Individual Differences in Inclusive Classrooms in Australia

    Science.gov (United States)

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

    2014-01-01

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

  13. 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.

  14. Modeling heat stress under different environmental conditions.

    Science.gov (United States)

    Carabaño, M J; Logar, B; Bormann, J; Minet, J; Vanrobays, M-L; Díaz, C; Tychon, B; Gengler, N; Hammami, H

    2016-05-01

    Renewed interest in heat stress effects on livestock productivity derives from climate change, which is expected to increase temperatures and the frequency of extreme weather events. This study aimed at evaluating the effect of temperature and humidity on milk production in highly selected dairy cattle populations across 3 European regions differing in climate and production systems to detect differences and similarities that can be used to optimize heat stress (HS) effect modeling. Milk, fat, and protein test day data from official milk recording for 1999 to 2010 in 4 Holstein populations located in the Walloon Region of Belgium (BEL), Luxembourg (LUX), Slovenia (SLO), and southern Spain (SPA) were merged with temperature and humidity data provided by the state meteorological agencies. After merging, the number of test day records/cows per trait ranged from 686,726/49,655 in SLO to 1,982,047/136,746 in BEL. Values for the daily average and maximum temperature-humidity index (THIavg and THImax) ranges for THIavg/THImax were largest in SLO (22-74/28-84) and shortest in SPA (39-76/46-83). Change point techniques were used to determine comfort thresholds, which differed across traits and climatic regions. Milk yield showed an inverted U-shaped pattern of response across the THI scale with a HS threshold around 73 THImax units. For fat and protein, thresholds were lower than for milk yield and were shifted around 6 THI units toward larger values in SPA compared with the other countries. Fat showed lower HS thresholds than protein traits in all countries. The traditional broken line model was compared with quadratic and cubic fits of the pattern of response in production to increasing heat loads. A cubic polynomial model allowing for individual variation in patterns of response and THIavg as heat load measure showed the best statistical features. Higher/lower producing animals showed less/more persistent production (quantity and quality) across the THI scale. The

  15. Neuromuscular coordination of squat lifting, II: Individual differences.

    Science.gov (United States)

    Scholz, J P; McMillan, A G

    1995-02-01

    This article reports individual differences in the coordination (ie, the relative timing of joint movements and muscle activity) of squat lifting identified by extended analysis of data reported in the authors' companion article in this issue. Two post hoc groups of 6 subjects each were identified from the original sample of 15 subjects based on qualitative differences in knee-lumbar spine relative motion plots during load acceleration. Subjects lifted a crate containing 15% to 75% of their maximum lifting capacity using a symmetrical squat-lift technique. Movement kinematic data were obtained with videography, and the electromyographic (EMG) activity of the vastus lateralis and erector spinae muscles was recorded with surface EMG. Measurements of coordination derived both kinematically and via EMG and the kinematic data were examined for group differences. Subjects in group 2 limited lumbar spine motion during load acceleration for all loads lifted, whereas those in group 1 limited lumbar spine motion more when lifting the heaviest loads. These differences were obvious both qualitatively, via knee-lumbar spine relative motion plots, and quantitatively, via measures of the relative timing of joint motions early in the lift. The effect of load on the coordination of these joints was the same for both post hoc groups after initial load acceleration. Significant differences in other kinematic measurements were also found between these groups. Despite specific instructions about how to lift the load, individual subjects coordinated their joints differently during the initial, accelerative phase of squat lifting. Individual differences in coordination in response to load increases could be categorized into two patterns, although the data of 2 subjects were difficult to categorize and thus not included in these analyses. Whether the two dominant patterns have consequences for stress to the joints during lifting remains to be determined.

  16. Accounting for Individual Differences in Human Associative Learning.

    Directory of Open Access Journals (Sweden)

    Nicola C Byrom

    2013-09-01

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

  17. Acceptance of cosmetic surgery: personality and individual difference predictors.

    Science.gov (United States)

    Swami, Viren; Chamorro-Premuzic, Tomas; Bridges, Stacey; Furnham, Adrian

    2009-01-01

    This study examined the association between several attitudinal constructs related to acceptance of cosmetic surgery, and participant demographics, personality, and individual difference variables. A sample of 332 university students completed a battery of scales comprising the Acceptance of Cosmetic Surgery Scale (ACSS) and measures of the Big Five personality factors, self-esteem, conformity, self-assessed attractiveness, and demographics. Multiple regressions showed that the predictor variables explained a large proportion of the variance in ACSS factors (Adj. R(2) ranging between .31 and .60). In addition, structural equation modelling revealed that distal factors (sex and age) were generally associated with acceptance of cosmetic surgery through the mediate influence of more proximate variables (in the first instance, the Big Five personality factors, followed by self-esteem and conformity, and finally self-assessed attractiveness). These results allow for the presentation of a preliminary model integrating personality and individual differences in predicting acceptance of cosmetic surgery.

  18. The importance of understanding individual differences in Down syndrome

    Science.gov (United States)

    Karmiloff-Smith, Annette; Al-Janabi, Tamara; D'Souza, Hana; Groet, Jurgen; Massand, Esha; Mok, Kin; Startin, Carla; Fisher, Elizabeth; Hardy, John; Nizetic, Dean; Tybulewicz, Victor; Strydom, Andre

    2016-01-01

    In this article, we first present a summary of the general assumptions about Down syndrome (DS) still to be found in the literature. We go on to show how new research has modified these assumptions, pointing to a wide range of individual differences at every level of description. We argue that, in the context of significant increases in DS life expectancy, a focus on individual differences in trisomy 21 at all levels—genetic, cellular, neural, cognitive, behavioral, and environmental—constitutes one of the best approaches for understanding genotype/phenotype relations in DS and for exploring risk and protective factors for Alzheimer’s disease in this high-risk population. PMID:27019699

  19. Risk perception and experience: hazard personality profiles and individual differences.

    Science.gov (United States)

    Barnett, J; Breakwell, G M

    2001-02-01

    The dominance of the "psychometric" paradigm and the consequent emphasis on personality profiles of hazards has resulted in little attention being given to individual variability in risk judgments. This study examines how far differences in experience of risk activities can explain individual variability in risk assessments. A questionnaire study (n = 172) was used to explore the relationships between experience and risk perceptions in relation to 16 risk activities. It was expected that these relationships would differ for voluntary and involuntary activities. Measures of experience included assessments of "impact" and "outcome" valence as well as "frequency." These three aspects of experience each related to risk assessment but their relationship depended on whether the risk experiences were voluntary or not. The results indicate the importance of developing more fine-grained ways of indexing risk experience.

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

    Science.gov (United States)

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

    2016-01-01

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

  1. Citric waste saccharification under different chemical treatments

    Directory of Open Access Journals (Sweden)

    Carlos Eduardo de Farias Silva

    2015-10-01

    Full Text Available Second generation ethanol from lignocellulose materials has been used in applications for food processing wastes. Since Brazil has a leading position in orange juice exports, the influence of acid and alkali pretreatments on liquor saccharification, solubilization of solid fraction and mass yield was evaluated. Time and Cacid or Calkaline at different concentrations of solids (low to moderate, 1 to 9% and high catalyst concentrations were analyzed. A hydrothermal pretreatment was conducted under the same conditions of acid and alkaline treatments to investigate the relative selectivity increase in using the catalysts. The chemical analyses of wastes indicated a 70% total carbohydrate level denoting a promising raw material for bioethanol production. Pretreatment caused acid saccharifications between 25 and 65% in total reducing sugars (TRS and mass yields (MY between 30 and 40%. In alkaline pretreatment, these rates ranged between 2 and 22.5% and between 30 and 80, respectively. In hydrothermal pretreatment, solubilized TRS varied between 3 and 37%, whereas MY remained between 45 and 60%, respectively. Cbiomass strongly influenced the three variables; in the same way, time affected MY.

  2. Team composition and conflict: the role of individual differences

    OpenAIRE

    Greer, Lindred Leura

    2008-01-01

    The effects of team composition and conflict on team outcomes have been largely contradictory. In this dissertation, I strive to unravel these relationships through better incorporating two key factors when understanding relationships between team composition, conflict, and team outcomes - the role of individual differences in perceptions and behaviors and the role of power as a critical determinant of team compositions. Using a mixture of field and laboratory data, I show that understanding ...

  3. 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...

  4. Individual differences in adult handwritten spelling-to-dictation

    OpenAIRE

    Bonin, Patrick; Méot, Alain; Millotte, Séverine; Barry, Christopher

    2013-01-01

    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,...

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

    Science.gov (United States)

    Demorest, Amy; Popovska, Ana; Dabova, Milena

    2012-02-01

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

  6. 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.

  7. Hybridization of mouse lemurs: different patterns under different ecological conditions

    Directory of Open Access Journals (Sweden)

    Rosenkranz David

    2011-10-01

    Full Text Available Abstract Background Several mechanistic models aim to explain the diversification of the multitude of endemic species on Madagascar. The island's biogeographic history probably offered numerous opportunities for secondary contact and subsequent hybridization. Existing diversification models do not consider a possible role of these processes. One key question for a better understanding of their potential importance is how they are influenced by different environmental settings. Here, we characterized a contact zone between two species of mouse lemurs, Microcebus griseorufus and M. murinus, in dry spiny bush and mesic gallery forest that border each other sharply without intermediate habitats between them. We performed population genetic analyses based on mtDNA sequences and nine nuclear microsatellites and compared the results to a known hybrid zone of the same species in a nearby wide gradient from dry spiny bush over transitional forest to humid littoral forest. Results In the spiny-gallery system, Microcebus griseorufus is restricted to the spiny bush; Microcebus murinus occurs in gallery forest and locally invades the dryer habitat of its congener. We found evidence for bidirectional introgressive hybridization, which is closely linked to increased spatial overlap within the spiny bush. Within 159 individuals, we observed 18 hybrids with mitochondrial haplotypes of both species. Analyses of simulated microsatellite data indicate that we identified hybrids with great accuracy and that we probably underestimated their true number. We discuss short-term climatic fluctuations as potential trigger for the dynamic of invasion and subsequent hybridization. In the gradient hybrid zone in turn, long-term aridification could have favored unidirectional nuclear introgression from Microcebus griseorufus into M. murinus in transitional forest. Conclusions Madagascar's southeastern transitional zone harbors two very different hybrid zones of mouse lemurs

  8. Hybridization of mouse lemurs: different patterns under different ecological conditions.

    Science.gov (United States)

    Hapke, Andreas; Gligor, Mark; Rakotondranary, S Jacques; Rosenkranz, David; Zupke, Oliver

    2011-10-11

    Several mechanistic models aim to explain the diversification of the multitude of endemic species on Madagascar. The island's biogeographic history probably offered numerous opportunities for secondary contact and subsequent hybridization. Existing diversification models do not consider a possible role of these processes. One key question for a better understanding of their potential importance is how they are influenced by different environmental settings. Here, we characterized a contact zone between two species of mouse lemurs, Microcebus griseorufus and M. murinus, in dry spiny bush and mesic gallery forest that border each other sharply without intermediate habitats between them. We performed population genetic analyses based on mtDNA sequences and nine nuclear microsatellites and compared the results to a known hybrid zone of the same species in a nearby wide gradient from dry spiny bush over transitional forest to humid littoral forest. In the spiny-gallery system, Microcebus griseorufus is restricted to the spiny bush; Microcebus murinus occurs in gallery forest and locally invades the dryer habitat of its congener. We found evidence for bidirectional introgressive hybridization, which is closely linked to increased spatial overlap within the spiny bush. Within 159 individuals, we observed 18 hybrids with mitochondrial haplotypes of both species. Analyses of simulated microsatellite data indicate that we identified hybrids with great accuracy and that we probably underestimated their true number. We discuss short-term climatic fluctuations as potential trigger for the dynamic of invasion and subsequent hybridization. In the gradient hybrid zone in turn, long-term aridification could have favored unidirectional nuclear introgression from Microcebus griseorufus into M. murinus in transitional forest. Madagascar's southeastern transitional zone harbors two very different hybrid zones of mouse lemurs in different environmental settings. This sheds light on the

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

    DEFF Research Database (Denmark)

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

    2011-01-01

    Hypothermia is a major cause of mortality in neonatal piglets. However, there are considerable individual differences in the successful recovery from postnatal hypothermia in the common farrowing environment, and so far the causes and interactions of causes have not been studied in detail. Using...... 635 crossbred neonatal piglets, the aim of this study was to identify the links among different physiological and behavioral measures and their connections to the piglets’ ability to overcome initial postnatal hypothermia, with rectal temperature at 2 h as the response variable. The data included...

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

    Science.gov (United States)

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

    2015-06-01

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

  11. Developmental and Individual Differences in Understanding of Fractions

    Science.gov (United States)

    Siegler, Robert S.; Pyke, Aryn A.

    2014-01-01

    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 cross sectional design. Results indicated that the difference between low achieving and higher achieving children’s fraction arithmetic knowledge, already substantial in 6th grade, was much greater in 8th grade. The fraction arithmetic knowledge of low achieving children was similar in the two grades, whereas higher achieving children showed much greater knowledge in 8th than 6th grade, despite both groups having been in the same classrooms, using the same textbooks, and having the same teachers and classmates. Individual differences in both fraction arithmetic and mathematics achievement test scores were predicted by differences in fraction magnitude knowledge and whole number division, even after the contributions of reading achievement and executive functioning were statistically controlled. Instructional implications of the findings are discussed. PMID:23244401

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

    Directory of Open Access Journals (Sweden)

    Mirela Mihić

    2010-06-01

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

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

    Science.gov (United States)

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

    2017-08-01

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

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

    Science.gov (United States)

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

    2015-07-01

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

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

    Science.gov (United States)

    Blanch, Angel; Balada, Ferran; Aluja, Anton

    2014-03-01

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

  16. Racial differences in coping strategies among individuals with epilepsy.

    Science.gov (United States)

    Bautista, Ramon Edmundo D

    2013-10-01

    The purpose of this study was to determine whether racial differences exist in the coping styles of individuals with epilepsy. This study utilized a survey of patients with epilepsy, including the Brief-COPE. One hundred thirteen Caucasians and 70 African-Americans comprised the study population. On univariate analysis, annual household income (pdisability benefits (pcoping reactions compared to Caucasians. Using ordinal logistic regression, the association between being African-American and the higher utilization of religion, positive reframing, planning, and denial as coping strategies remained statistically significant. Among individuals with epilepsy, African-Americans appear to utilize more engagement-type coping reactions when compared to Caucasians but also utilize more denial. © 2013.

  17. Individual Differences in Adolescents' Emotional Reactivity across Relationship Contexts.

    Science.gov (United States)

    Cook, Emily C; Blair, Bethany L; Buehler, Cheryl

    2018-02-01

    Understanding individual differences in adolescents' ability to regulate emotions within interpersonal relationships is paramount for healthy development. Thus, the effect of individual vulnerabilities (depressive affect, social anxiety, self-blame, and coping efficacy problems) on the transmission of emotional reactivity in response to conflict from family to peers (friends and romantic partners) was prospectively examined across six waves of data in a community-based sample of 416 adolescents (M age Wave 1 = 11.90, 51% girls). Multiple-group models estimated in structural equation modeling suggested that youth who were higher in social anxiety or coping efficacy problems were more likely to transmit emotional reactivity developed in the family-of-origin to emotional reactivity in response to conflict in close friendships. Additionally, those youth higher in self-blame and depressive affect were more likely to transmit emotional reactivity from friendships to romantic relationships.

  18. Religion as attachment: normative processes and individual differences.

    Science.gov (United States)

    Granqvist, Pehr; Mikulincer, Mario; Shaver, Phillip R

    2010-02-01

    The authors review findings from the psychology of religion showing that believers' perceived relationships with God meet the definitional criteria for attachment relationships. They also review evidence for associations between aspects of religion and individual differences in interpersonal attachment security and insecurity. They focus on two developmental pathways to religion. The first is a "compensation" pathway involving distress regulation in the context of insecure attachment and past experiences of insensitive caregiving. Research suggests that religion as compensation might set in motion an "earned security" process for individuals who are insecure with respect to attachment. The second is a "correspondence" pathway based on secure attachment and past experiences with sensitive caregivers who were religious. The authors also discuss conceptual limitations of a narrow religion-as-attachment model and propose a more inclusive framework that accommodates concepts such as mindfulness and "nonattachment" from nontheistic religions such as Buddhism and New Age spirituality.

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

    Science.gov (United States)

    Olderbak, Sally; Wilhelm, Oliver

    2017-10-01

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

  20. "Sticker Shock" in Individual Insurance under Health Reform

    OpenAIRE

    Mark Pauly; Scott Harrington; Adam Leive

    2014-01-01

    This paper provides estimates of the changes in premiums, average or expected out of pocket payments, and the sum of premiums and out of pocket payments (total expected price) for a sample of consumers who bought individual insurance in 2010 to 2012, comparing total expected prices before the Affordable Care Act with estimates of total expected prices if they were to purchase silver or bronze coverage after reform, before the effects of any premium subsidies. We provide comparisons for purcha...

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

    Science.gov (United States)

    McIntyre, Miranda M; Graziano, William G

    2016-09-01

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

  2. Cohesion and adaptability among individuals under treatment for infertility.

    Science.gov (United States)

    Hidalgo, Maria Paz Loayza; Caleffi, Lorena; Baron, Ana; Mattana, Eunice; Chaves, Marcia Lorena F

    2004-02-01

    The objective of this study was to evaluate cohesion and adaptability as relationship patterns of individuals in the presence or absence of infertility. Infertile subjects (20 men and 26 women, age 29.9 yr., SD = 3.8), and 100 fertile individuals (52 men and 48 women, age 29.5 yr., SD = 3.6) were included in this cross-sectional study conducted in Brazil. Subjects were married for the first time and had no children. The pattern of relationship (cohesion and adaptability) was assessed on the Family Adaptability and Cohesion Evaluation Scale (FACES III). Subjects were also interviewed and the interviews tape-recorded and analyzed by independent and blinded senior psychiatrists. The concepts of cohesion and adaptability did not differentiate infertile couples from fertile ones. Further, the recorded interviews also resulted in heterogeneous. nonconcordant judgments. These results lead to two conclusions: that awareness of infertility is not present in the population studied or that it is present but the magnitude of its effect is quite small and that FACES III and the interview focus on adaptability and cohesion are not sensitive enough to measure the difficulties in these couples' relationships. This leads us to reflect on the type of psychiatric support available to infertile couples.

  3. The decomposition of estuarine macrophytes under different ...

    African Journals Online (AJOL)

    The low levels of total oxidised nitrogen (nitrate and nitrite) released during decomposition were attributed to the inhibition of nitrification by heterotrophic bacteria under anoxic conditions. The relative levels of dissolved inorganic phosphorus (DIP) released were lower than that observed for DIN, and peaked early on in the ...

  4. Autobiographical remembering and individual differences in emotional intelligence.

    Science.gov (United States)

    Yamamoto, Kohsuke; Toyota, Hiroshi

    2013-06-01

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

  5. Individual Difference Variables, Affective Differentiation, and the Structures of Affect

    Science.gov (United States)

    Terracciano, Antonio; McCrae, Robert R.; Hagemann, Dirk; Costa, Paul T.

    2008-01-01

    Methodological arguments are usually invoked to explain variations in the structure of affect. Using self-rated affect from Italian samples (N = 600), we show that individual difference variables related to affective differentiation can moderate the observed structure. Indices of circumplexity (Browne, 1992) and congruence coefficients to the hypothesized target were used to quantify the observed structures. Results did not support the circumplex model as a universal structure. A circular structure with axes of activation and valence was approximated only among more affectively differentiated groups: students and respondents with high scores on Openness to Feelings and measures of negative emotionality. A different structure, with unipolar Positive Affect and Negative Affect factors, was observed among adults and respondents with low Openness to Feelings and negative emotionality. The observed structure of affect will depend in part on the nature of the sample studied. PMID:12932207

  6. 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.

  7. Inattentional Blindness and Individual Differences in Cognitive Abilities

    Science.gov (United States)

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

    2015-01-01

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

  8. A neuroimaging investigation of attribute framing and individual differences

    Science.gov (United States)

    Murch, Kevin B.

    2014-01-01

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

  9. 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.

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

    Science.gov (United States)

    Kidd, Gary R.

    2004-05-01

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

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

    Science.gov (United States)

    Lippa, Richard

    1995-01-01

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

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

    Science.gov (United States)

    Travis, Frederick T; Wallace, Robert Keith

    2015-01-01

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

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

    Directory of Open Access Journals (Sweden)

    Frederick T Travis

    2015-01-01

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

  14. Predicting Performance Under Acute Stress : The Role of Individual Characteristics

    NARCIS (Netherlands)

    Delahaij, R.; Dam, K. van; Gaillard, A.W.K.; Soeters, J.

    2011-01-01

    This prospective study examined how differences in coping style, coping self-efficacy, and metacognitive awareness influence coping behavior and performance during a realistic acute stressful exercise in 2 military samples (n = 122 and n = 132). Results showed that coping self-efficacy and coping

  15. Individual differences in decision making by foraging hummingbirds.

    Science.gov (United States)

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

    2014-11-01

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

  16. Modeling heat stress under different environmental conditions

    OpenAIRE

    Carabano, Maria-Jesus; Logar, Betka; Bormann, Jeanne; Minet, Julien; Vanrobays, ML; Diaz, Clara; Tychon, Bernard; Gengler, Nicolas; Hammami, Hedi

    2016-01-01

    Renewed interest in heat stress effects on livestock productivity derives from climate change, which is expected to increase temperatures and the frequency of extreme weather events. This study aimed at evaluating the effect of temperature and humidity on milk production in highly selected dairy cattle populations across three European regions differing in climate and production systems to detect differences and similarities that can be used to optimize heat stress (HS) effect modeling. Mi...

  17. Behavior of Confined Columns under Different Techniques

    OpenAIRE

    Mostafa Osman; Ata El-Kareim Shoeib Soliman

    2015-01-01

    Since columns are the most important elements of the structures, failure of one column in a critical location can cause a progressive collapse. In this respect, the repair and strengthening of columns is a very important subject to reduce the building failure and to keep the columns capacity. Twenty columns with different parameters is tested and analysis. Eleven typical confined reinforced concrete (RC) columns with different types of techniques are assessment. And also,...

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

    Science.gov (United States)

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

    2010-08-01

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

  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. Individual differences, aging, and IQ in two-choice tasks.

    Science.gov (United States)

    Ratcliff, Roger; Thapar, Anjali; McKoon, Gail

    2010-05-01

    The effects of aging and IQ on performance were examined in three two-choice tasks: numerosity discrimination, recognition memory, and lexical decision. The experimental data, accuracy, correct and error response times, and response time distributions, were well explained by Ratcliff's (1978) diffusion model. The components of processing identified by the model were compared across levels of IQ (ranging from 83 to 146) and age (college students, 60-74, and 75-90 year olds). Declines in performance with age were not significantly different for low compared to high IQ subjects. IQ but not age had large effects on the quality of the evidence that was obtained from a stimulus or memory, that is, the evidence upon which decisions were based. Applying the model to individual subjects, the components of processing identified by the model for individuals correlated across tasks. In addition, the model's predictions and the data were examined for the "worst performance rule", the finding that age and IQ have larger effects on slower responses than faster responses. Copyright 2009 Elsevier Inc. All rights reserved.

  1. 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.

  2. Soil aggregation under different management systems

    Directory of Open Access Journals (Sweden)

    Cibele Mascioli Rebello Portella

    2012-12-01

    Full Text Available Considering that the soil aggregation reflects the interaction of chemical, physical and biological soil factors, the aim of this study was evaluate alterations in aggregation, in an Oxisol under no-tillage (NT and conventional tillage (CT, since over 20 years, using as reference a native forest soil in natural state. After analysis of the soil profile (cultural profile in areas under forest management, samples were collected from the layers 0-5, 5-10, 10-20 and 20-40 cm, with six repetitions. These samples were analyzed for the aggregate stability index (ASI, mean weighted diameter (MWD, mean geometric diameter (MGD in the classes > 8, 8-4, 4-2, 2-1, 1-0.5, 0.5-0.25, and < 0.25 mm, and for physical properties (soil texture, water dispersible clay (WDC, flocculation index (FI and bulk density (Bd and chemical properties (total organic carbon - COT, total nitrogen - N, exchangeable calcium - Ca2+, and pH. The results indicated that more intense soil preparation (M < NT < PC resulted in a decrease in soil stability, confirmed by all stability indicators analyzed: MWD, MGD, ASI, aggregate class distribution, WDC and FI, indicating the validity of these indicators in aggregation analyses of the studied soil.

  3. 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.

  4. 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.

  5. Individual differences and correlates of highly superior autobiographical memory.

    Science.gov (United States)

    Patihis, Lawrence

    2016-08-01

    Highly superior autobiographical memory (HSAM) is a recently identified ability that has been difficult to explain with existing memory science. The present study measured HSAM participants' and age/gender-matched controls' on a number of behavioural measures to test three main hypotheses: imaginative absorption, emotional arousal, and sleep. HSAM participants were significantly higher than controls on the dispositions absorption and fantasy proneness. These two dispositions also were associated with a measure of HSAM ability within the hyperthymesia participants. The emotional-arousal hypothesis yielded only weak support. The sleep hypothesis was not supported in terms of quantity, but sleep quality may be a small factor worthy of further research. Other individual differences are also documented using a predominantly exploratory analysis. Speculative pathways describing how the tendencies to absorb and fantasise could lead to enhanced autobiographical memory are discussed.

  6. Dissociative style and individual differences in verbal working memory span.

    Science.gov (United States)

    de Ruiter, Michiel B; Phaf, R Hans; Elzinga, Bernet M; van Dyck, Richard

    2004-12-01

    Dissociative style is mostly studied as a risk factor for dissociative pathology, but it may also reflect a fundamental characteristic of healthy information processing. Due to the close link between attention and working memory and the previous finding of enhanced attentional abilities with a high dissociative style, a positive relationship was also expected between dissociative style and verbal working memory span. In a sample of 119 psychology students, it was found that the verbal span of the high-dissociative group was about half a word larger than of the medium and low-dissociative groups. It is suggested that dissociative style may be one of only very few individual differences that is directly relevant to consciousness research.

  7. Individual differences in situation awareness: Validation of the Situationism Scale

    Science.gov (United States)

    Roberts, Megan E.; Gibbons, Frederick X.; Gerrard, Meg; Klein, William M. P.

    2015-01-01

    This paper concerns the construct of lay situationism—an individual’s belief in the importance of a behavior’s context. Study 1 identified a 13-item Situationism Scale, which demonstrated good reliability and validity. In particular, higher situationism was associated with greater situation-control (strategies to manipulate the environment in order to avoid temptation). Subsequent laboratory studies indicated that people higher on the situationism subscales used greater situation-control by sitting farther from junk food (Study 2) and choosing to drink non-alcoholic beverages before a cognitive task (Study 3). Overall, findings provide preliminary support for the psychometric validity and predictive utility of the Situationism Scale and offer this individual difference construct as a means to expand self-regulation theory. PMID:25329242

  8. Declarative and Procedural Memory as Individual Differences in Second Language Acquisition

    Science.gov (United States)

    Morgan-Short, Kara; Faretta-Stutenberg, Mandy; Brill-Schuetz, Katherine A.; Carpenter, Helen; Wong, Patrick C. M.

    2014-01-01

    This study examined how individual differences in cognitive abilities account for variance in the attainment level of adult second language (L2) syntactic development. Participants completed assessments of declarative and procedural learning abilities. They subsequently learned an artificial L2 under implicit training conditions and received…

  9. The Multifold Relationship between Memory and Decision Making: An Individual-Differences Study

    Science.gov (United States)

    Del Missier, Fabio; Mäntylä, Timo; Hansson, Patrik; Bruine de Bruin, Wändi; Parker, Andrew M.; Nilsson, Lars-Göran

    2013-01-01

    Several judgment and decision-making tasks are assumed to involve memory functions, but significant knowledge gaps on the memory processes underlying these tasks remain. In a study on 568 adults between 25 and 80 years of age, hypotheses were tested on the specific relationships between individual differences in working memory, episodic memory,…

  10. Impaired decision making under ambiguity but not under risk in individuals with pathological buying-behavioral and psychophysiological evidence.

    Science.gov (United States)

    Trotzke, Patrick; Starcke, Katrin; Pedersen, Anya; Müller, Astrid; Brand, Matthias

    2015-09-30

    Pathological buying (PB) is described as dysfunctional buying behavior, associated with harmful consequences. It is discussed whether decision-making deficits are related to PB, because affected individuals often choose the short-term rewarding option of buying despite persistent negative long-term consequences. We investigated 30 patients suffering from PB and 30 matched control participants with two different decision-making tasks: the Iowa Gambling Task (IGT) measures decisions under ambiguity and involves emotional feedback processing, whereas the Game of Dice Task (GDT) measures decisions under risk and can be solved strategically. Potential emotional and cognitive correlates of decision making were investigated by assessing skin conductance response (SCR) and executive functioning. In comparison to the control participants, the patients showed more disadvantageous decisions under ambiguity in the IGT. These data were supported by the SCR results: patients failed to generate SCRs that usually occur before disadvantageous decisions. The physiological and behavioral performance on decisions under risk and executive functioning did not differ between groups. Thus, deficits in emotional feedback processing might be one potential factor in etiology and pathogenesis of PB and should be considered in theory and treatment. Copyright © 2015. Published by Elsevier Ireland Ltd.

  11. 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

  12. Contrast edge colors under different natural illuminations.

    Science.gov (United States)

    Nieves, Juan Luis; Nascimento, Sérgio M C; Romero, Javier

    2012-02-01

    Essential to sensory processing in the human visual system is natural illumination, which can vary considerably not only across space but also along the day depending on the atmospheric conditions and the sun's position in the sky. In this work, edges derived from the three postreceptoral Luminance, Red-Green, and Blue-Yellow signals were computed from hyperspectral images of natural scenes rendered with daylights of Correlated Color Temperatures (CCTs) from 2735 to 25,889 K; for low CCT, the same analysis was performed using Planckian illuminants up to 800 K. It was found that average luminance and chromatic edge contrasts were maximal for low correlated color temperatures and almost constants above 10,000 K. The magnitude of these contrast changes was, however, only about 2% across the tested daylights. Results suggest that the postreceptoral opponent and nonopponent color vision mechanisms produce almost constant responses for color edge detection under natural illumination. © 2012 Optical Society of America

  13. ( Arachis hypogeae ) Yield Performance under different Weeding ...

    African Journals Online (AJOL)

    A two–year field experiment was conducted at the Teaching and Research Farm of the Ekiti State University, Ado – Ekiti, Nigeria, during 2008 and 2009 cropping seasons to determine the effects of different weeding regimes on soil chemical properties and yield of groundnut (Arachis hypogeae). The experiment was laid out ...

  14. Individual but not fragile: individual differences in task control predict Stroop facilitation.

    Science.gov (United States)

    Kalanthroff, E; Henik, A

    2013-06-01

    The Stroop effect is composed of interference and facilitation effects. The facilitation is less stable and thus many times is referred to as a "fragile effect". Here we suggest the facilitation effect is highly vulnerable to individual differences in control over the task conflict (between relevant color naming and irrelevant word reading in the Stroop task). We replicated previous findings of a significant correlation between stop-signal reaction time (SSRT) and Stroop interference, and also found a significant correlation between SSRT and the Stroop facilitation effect-participants with low inhibitory control (i.e., long SSRT) had no facilitation effect or even a reversed one. These results shed new light on the "fragile" facilitation effect and highlight the necessity of awareness of task conflict, especially in the Stroop task. Copyright © 2013 Elsevier Inc. All rights reserved.

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

    Directory of Open Access Journals (Sweden)

    Susan B Perlman

    2009-06-01

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

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

    Science.gov (United States)

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

    2009-06-22

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

  18. 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.

  19. Mechanisms Underlying Sex Differences in Cannabis Use.

    Science.gov (United States)

    Calakos, Katina C; Bhatt, Shivani; Foster, Dawn W; Cosgrove, Kelly P

    2017-12-01

    Cannabis is the most commonly used illicit substance worldwide. In recent decades, highly concentrated products have flooded the market, and prevalence rates have increased. Gender differences exist in cannabis use, as men have higher prevalence of both cannabis use and cannabis use disorder (CUD), while women progress more rapidly from first use to CUD. This paper reviews findings from preclinical and human studies examining the sex-specific neurobiological underpinnings of cannabis use and CUD, and associations with psychiatric symptoms. Sex differences exist in the endocannabinoid system, in cannabis exposure effects on brain structure and function, and in the co-occurrence of cannabis use with symptoms of anxiety, depression and schizophrenia. In female cannabis users, anxiety symptoms correlate with larger amygdala volume and social anxiety disorder symptoms correlate with CUD symptoms. Female cannabis users are reported to be especially vulnerable to earlier onset of schizophrenia, and mixed trends emerge in the correlation of depressive symptoms with cannabis exposure in females and males. As prevalence of cannabis use may continue to increase given the shifting policy landscape regarding marijuana laws, understanding the neurobiological mechanisms of cannabis exposure in females and males is key. Examining these mechanisms may help inform future research on sex-specific pharmacological and behavioral interventions for women and men with high-risk cannabis use, comorbid psychiatric disease, and CUD.

  20. Visual attention is not enough: Individual differences in statistical word-referent learning in infants.

    Science.gov (United States)

    Smith, Linda B; Yu, Chen

    2013-01-01

    Recent evidence shows that infants can learn words and referents by aggregating ambiguous information across situations to discern the underlying word-referent mappings. Here, we use an individual difference approach to understand the role of different kinds of attentional processes in this learning: 12-and 14-month-old infants participated in a cross-situational word-referent learning task in which the learning trials were ordered to create local novelty effects, effects that should not alter the statistical evidence for the underlying correspondences. The main dependent measures were derived from frame-by-frame analyses of eye gaze direction. The fine- grained dynamics of looking behavior implicates different attentional processes that may compete with or support statistical learning. The discussion considers the role of attention in binding heard words to seen objects, individual differences in attention and vocabulary development, and the relation between macro-level theories of word learning and the micro-level dynamic processes that underlie learning.

  1. Sex differences in intrinsic brain functional connectivity underlying human shyness.

    Science.gov (United States)

    Yang, Xun; Wang, Siqi; Kendrick, Keith Maurice; Wu, Xi; Yao, Li; Lei, Du; Kuang, Weihong; Bi, Feng; Huang, Xiaoqi; He, Yong; Gong, Qiyong

    2015-12-01

    Shyness is a fundamental trait associated with social-emotional maladaptive behaviors, including many forms of psychopathology. Neuroimaging studies have demonstrated that hyper-responsivity to social and emotional stimuli occurs in the frontal cortex and limbic system in shy individuals, but the relationship between shyness and brain-wide functional connectivity remains incompletely understood. Using resting-state functional magnetic resonance imaging, we addressed this issue by exploring the relationship between regional functional connectivity strength (rFCS) and scores of shyness in a cohort of 61 healthy young adults and controlling for the effects of social and trait anxiety scores. We observed that the rFCS of the insula positively correlated with shyness scores regardless of sex. Furthermore, we found that there were significant sex-by-shyness interactions in the dorsal anterior cingulate cortex and insula (two core nodes of the salience network) as well as the subgenual anterior cingulate cortex: the rFCS values of these regions positively correlated with shyness scores in females but negatively correlated in males. Taken together, we provide evidence for intrinsic functional connectivity differences in individuals with different degrees of shyness and that these differences are sex-dependent. These findings might have important implications on the understanding of biological mechanisms underlying emotional and cognitive processing associated with shyness. © The Author (2015). Published by Oxford University Press. For Permissions, please email: journals.permissions@oup.com.

  2. Individual Differences in Accurately Judging Personality From Text.

    Science.gov (United States)

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

    2016-08-01

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

  3. 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.

  4. 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. © The Author(s) 2015.

  5. 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.

  6. 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.

  7. Individual differences in adult handwritten spelling-to-dictation.

    Science.gov (United States)

    Bonin, Patrick; Méot, Alain; Millotte, Séverine; Barry, Christopher

    2013-01-01

    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 (1) there was both within- and between-session reliability across the sets of items, (2) there was no trade-off between the utilization of lexical and non-lexical information, and (3) 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.

  8. Individual differences and the creation of false childhood memories.

    Science.gov (United States)

    Hyman, I E; Billings, F J

    1998-01-01

    We investigated if college students will create false childhood memories, the role of self-knowledge in memory creation, and if there are reliable individual differences related to memory creation. Based on information obtained from parents, we asked college students about several true childhood experiences. We also asked each student about one false event and presented the false event as if it was based on parent information. We asked the students to describe all events in two interviews separated by one day. When participants could not recall an event (whether true or false), we encouraged them to think about related self-knowledge and to try to imagine the event. In an unrelated experimental session, the students were administered four cognitive/personality scales: the Creative Imagination Scale (CIS), the Tellegen Absorption Scale (TAS), the Dissociative Experiences Scale (DES), and the Marlowe-Crowne Social Desirability Scale (SDS). We found that approximately 25% of the students created false childhood memories. Participants who made connections to related self-knowledge in the first interview were more likely to create false memories. We also found that the CIS and the DES were positively related to memory creation. Factors that decrease one's ability to engage in reality monitoring are related to the acceptance of false events and the creation of false memories.

  9. Understanding individual differences in word recognition skills of ESL children.

    Science.gov (United States)

    Geva, E; Yaghoub-Zadeh, Z; Schuster, B

    2000-01-01

    This paper focuses on the extent to which the development of ESL (English as a Second Language) word recognition skills mimics similar trajectories in same-aged EL1 (English as a First Language) children, and the extent to which phonological processing skills and rapid naming can be used to predict word recognition performance in ESL children. Two cohorts of Grade 1 ESL and EL1 primary-level children were followed for two consecutive years. Results indicated that vocabulary knowledge, a measure of language proficiency, and nonverbal intelligence were not significant predictors of word recognition in either group. Yet, by considering individual differences in phonological awareness and rapid naming, it was possible to predict substantial amounts of variance on word recognition performance six months and one year later in both language groups. Commonality analyses indicated that phonological awareness and rapid naming contributed unique variance to word recognition performance. Moreover, the profiles of not at-risk children in the EL1 and ESL groups were similar on all but the oral language measure, where EL1 children had the advantage. In addition, EL1 and ESL profiles of children who had word-recognition difficulty were similar, with low performance on rapid naming and phonological awareness. Results indicate that these measures are reliable indicators of potential reading disability among ESL children.

  10. The Sunk Cost Fallacy and Individual Differences in Health Decisions

    Science.gov (United States)

    Fernandez, Norma Patricia

    2010-01-01

    The Sunk Cost fallacy is a biased committed when individuals base their decisions to stop or continue a course of action solely on past irrecoverable invested costs (i.e., monetary or time-related). Individuals' susceptibility to the Sunk Cost fallacy has been justified as the need to try to avoid appearing wasteful, to avoid appearing…

  11. Children's perceptions about medicines: individual differences and taste.

    Science.gov (United States)

    Mennella, Julie A; Roberts, Kristi M; Mathew, Phoebe S; Reed, Danielle R

    2015-09-21

    Bitter taste receptors are genetically diverse, so children likely vary in sensitivity to the "bad" taste of some pediatric formulations. Based on prior results that variation in a bitter taste receptor gene, TAS2R38, was related to solid (pill) formulation usage, we investigated whether this variation related to liquid formulation usage and young children's reports of past experiences with medicines and whether maternal reports of these past experiences were concordant with those of their children. We conducted retrospective interviews of 172 children 3 to 10 years old and their mothers (N = 130) separately in a clinical research setting about issues related to medication usage. Children were genotyped for the TASR38 variant A49P (alanine to proline at position 49). Children's responses were compared with their TAS2R38 genotype and with maternal reports. Children (>4 years) reported rejecting medication primarily because of taste complaints, and those with at least one sensitive TAS2R38 allele (AP or PP genotype) were more likely to report rejecting liquid medications than were those without a taster allele (AA genotype; χ(2) = 5.72, df = 1, p = 0.02). Children's and mothers' reports of the children's past problems with medication were in concordance (p = 0.03). Individual differences in taste responses to medications highlight the need to consider children's genetic variation and their own perceptions when developing formulations acceptable to the pediatric palate. Pediatric trials could systematically collect valid information directly from children and from their caregivers regarding palatability (rejection) issues, providing data to develop well-accepted pediatric formulations that effectively treat illnesses for all children. Clinicaltrials.gov protocol registration system (NCT01407939). Registered 19 July 2011.

  12. Individual Differences in Premotor Brain Systems Underlie Behavioral Apathy

    Science.gov (United States)

    Bonnelle, Valerie; Manohar, Sanjay; Behrens, Tim; Husain, Masud

    2016-01-01

    Lack of physical engagement, productivity, and initiative—so-called “behavioral apathy”—is a common problem with significant impact, both personal and economic. Here, we investigate whether there might be a biological basis to such lack of motivation using a new effort and reward-based decision-making paradigm, combined with functional and diffusion-weighted imaging. We hypothesized that behavioral apathy in otherwise healthy people might be associated with differences in brain systems underlying either motivation to act (specifically in effort and reward-based decision-making) or in action processing (transformation of an intention into action). The results demonstrate that behavioral apathy is associated with increased effort sensitivity as well as greater recruitment of neural systems involved in action anticipation: supplementary motor area (SMA) and cingulate motor zones. In addition, decreased structural and functional connectivity between anterior cingulate cortex (ACC) and SMA were associated with increased behavioral apathy. These findings reveal that effort sensitivity and translation of intentions into actions might make a critical contribution to behavioral apathy. We propose a mechanism whereby inefficient communication between ACC and SMA might lead to increased physiological cost—and greater effort sensitivity—for action initiation in more apathetic people. PMID:26564255

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

    Directory of Open Access Journals (Sweden)

    Yuri G. Pavlov

    2015-01-01

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

  14. Millennials' Career Expectations: Exploring Attitudes and Individual Differences

    OpenAIRE

    Lovorka Galetić; Maja Klindžić; Ivana Načinović Braje

    2016-01-01

    Generation Y individuals or Millennials are known for their unique views, work values and motivational needs which implies that, in order to attract and retain those individuals, activities in the area of career management should be given special attention by HRM managers. After a theoretical background on Millennials' life and work attitudes, an empirical research on career preferences of Millennials in Croatia was described. Empirical research was conducted among 249 members of generation Y...

  15. Exploring Individual Differences in Attitudes toward Audience Response Systems

    Directory of Open Access Journals (Sweden)

    Robin Kay

    2009-09-01

    Full Text Available 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 toward ARSs than female students. Students who were more comfortable with computers had significantly more positive attitudes than students who were less comfortable. Students who did not actively participate in class before ARSs were used were more positive about this tool than students who regularly participated. Finally, students were significantly more positive about ARSs when they were used for formative (not for grades as opposed to summative (for grades assessment. There were no significant differences observed for grade level or subject area taught. Résumé La présente étude visait à étudier les variations personnelles dans la disposition des élèves du secondaire envers l’utilisation de systèmes de réponse, ou télévoteurs, en classe. Plus précisément, l’étude a examiné l’impact du sexe, de l’année d’études, de la matière, de l’aisance en informatique, du niveau de participation et du type d’utilisation sur 659 élèves. La disposition des garçons envers les télévoteurs était significativement meilleure que celle des filles. De plus, les élèves les plus à l’aise avec les ordinateurs avaient une réponse significativement plus positive que les élèves moins à l’aise. Les élèves qui ne participaient pas activement en classe avant l’utilisation de télévoteurs avaient quant à eux une attitude plus positive envers cet outil que les élèves qui participaient déjà régulièrement. Enfin, les élèves démontraient une attitude plus favorable envers les télévoteurs lorsque ceux-ci étaient utilisés aux fins d’évaluations formatives (non not

  16. Second Language Pragmatic Ability: Individual Differences According to Environment

    Science.gov (United States)

    Wyner, Lauren; Cohen, Andrew D.

    2015-01-01

    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…

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

    Science.gov (United States)

    Shute, Valerie J.

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

  18. 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…

  19. Individual Difference Effects in Human-Computer Interaction

    Science.gov (United States)

    1991-10-01

    DAVID DOS - a modified version of DOS 3.3.) 4.1.2.1.2 REMOTE DATABASE This option allows the experinenter to communicate with a remote database...Gardner, R.W., Holzman , P.S., Klein, G.S., Lintnn, H.B., and Spence, D.P., "Cognitive Control: A Study of Individual Consistencies in Cognitive

  20. Individual differences in cardiovascular response to social challenge

    NARCIS (Netherlands)

    Sgoifo, A; Costoli, T; Meerlo, P; Buwalda, B; Pico'Alfonso, MA; De Boer, S; Musso, E; Koolhaas, J

    2005-01-01

    An important determinant of cardiovascular stress reactivity and morbidity is the individual behavioral strategy of coping with social challenge. This review summarizes the results of a number of studies that we performed in rats, aimed at investigating the relationship between aggression and

  1. Individual Differences in Boredom Proneness amongst Truck Drivers ...

    African Journals Online (AJOL)

    esteem and locus of control individually and jointly predicted boredom proneness amongst truck drivers. The same variables jointly accounted for 67% of the proportion of the variance in boredom proneness. Results of the 2 x 2 x 2 ANOVA also ...

  2. Sustained attention in language production: An individual differences investigation

    NARCIS (Netherlands)

    Jongman, S.R.; Roelofs, A.P.A.; Meyer, A.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

  3. An Individual-Based Diploid Model Predicts Limited Conditions Under Which Stochastic Gene Expression Becomes Advantageous

    KAUST Repository

    Matsumoto, Tomotaka

    2015-11-24

    Recent studies suggest the existence of a stochasticity in gene expression (SGE) in many organisms, and its non-negligible effect on their phenotype and fitness. To date, however, how SGE affects the key parameters of population genetics are not well understood. SGE can increase the phenotypic variation and act as a load for individuals, if they are at the adaptive optimum in a stable environment. On the other hand, part of the phenotypic variation caused by SGE might become advantageous if individuals at the adaptive optimum become genetically less-adaptive, for example due to an environmental change. Furthermore, SGE of unimportant genes might have little or no fitness consequences. Thus, SGE can be advantageous, disadvantageous, or selectively neutral depending on its context. In addition, there might be a genetic basis that regulates magnitude of SGE, which is often referred to as “modifier genes,” but little is known about the conditions under which such an SGE-modifier gene evolves. In the present study, we conducted individual-based computer simulations to examine these conditions in a diploid model. In the simulations, we considered a single locus that determines organismal fitness for simplicity, and that SGE on the locus creates fitness variation in a stochastic manner. We also considered another locus that modifies the magnitude of SGE. Our results suggested that SGE was always deleterious in stable environments and increased the fixation probability of deleterious mutations in this model. Even under frequently changing environmental conditions, only very strong natural selection made SGE adaptive. These results suggest that the evolution of SGE-modifier genes requires strict balance among the strength of natural selection, magnitude of SGE, and frequency of environmental changes. However, the degree of dominance affected the condition under which SGE becomes advantageous, indicating a better opportunity for the evolution of SGE in different genetic

  4. 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. © The Author(s) 2010.

  5. Early development and the emergence of individual differences in behavior among littermates of wild rabbit pups.

    Science.gov (United States)

    Rödel, Heiko G; Bautista, Amando; Roder, Manuel; Gilbert, Caroline; Hudson, Robyn

    2017-05-01

    The ontogeny of associated individual differences in behavior and physiology during early postnatal life, and in particular the emergence of such differences among litter siblings, has been hardly explored in mammals under natural conditions. We studied such within-litter differences in behavior in European rabbit pups Oryctolagus cuniculus prior to weaning, and whether and how these differences co-varied with other individual characteristics such as postnatal body temperature and early growth. The study was conducted under semi-natural conditions in a colony of rabbits of wild origin, where the young were born and developed in nursery burrows. We equipped two siblings per litter with interscapular skin temperature loggers on postnatal day 2 and recorded temperature profiles for 48h. Individual body (skin) temperatures of pups within litters were repeatable across time, indicating the existence of consistent individual differences. Such differences within litters were associated with relative differences in pre-weaning growth, revealing that relatively warmer pups showed a greater increase in body mass during the nest period. Between postnatal days 12 and 17, after the pups had reached a developmental stage of greater mobility, we carried out different behavioral tests: a handling-restraint test, an open field test and a jump-down test from a platform. Individual responses in the former two tests were associated, as those pups showing a quicker struggling response to restraint during handling also exhibited greater exploratory activity in the open field. This correlation across contexts suggests the existence of personality types in wild rabbits at an early developmental stage. Furthermore, pups' behavioral responses were strongly associated with their relative within-litter body mass at testing. Animals with a lower body mass compared to their siblings showed a relatively quicker struggle response to handling restraint and covered a relatively larger distance in

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

    Science.gov (United States)

    Ormel, Johan; Aleman, André

    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 also operate as top–down control mechanism. We sought to investigate whether such individual differences would be associated with brain activity elicited during reappraisal of negative emotion. Eighteen healthy participants completed a functional magnetic resonance imaging task that involved attending to or reappraising negative stimuli, and provided emotion experience ratings after each trial. Dispositional mindfulness was assessed with a self-report questionnaire. Reappraisal induced activity in a brain network involving predominantly dorsal portions of the prefrontal cortex, replicating previous studies. A voxelwise regression analysis showed that individual differences in the tendency to be mindful predicted activity in neural regions underlying reappraisal, with dorsomedial prefrontal cortex activation increasing with more mindfulness traits. Notably, this prefrontal activation was inversely correlated with the amygdala response to negative scenes, further supporting its role in down-regulating emotion-generation regions. These findings suggest that individual differences in dispositional mindfulness, which reflect the tendency to recognize and regulate current states, may modulate activity in neural systems involved in the effective cognitive control of negative emotion. PMID:20147457

  7. Defining the biological bases of individual differences in musicality

    NARCIS (Netherlands)

    Gingras, B.; Honing, H.; Peretz, I.; Trainor, L.J.; Fisher, S.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

  8. Individual Differences in White Matter Diffusion Affect Sleep Oscillations

    NARCIS (Netherlands)

    Piantoni, G.; Poil, S.S.; Linkenkaer-Hansen, K.; Verweij, I.M.; Ramautar, J.R.; van Someren, E.J.W.; van der Werf, Y.D.

    2013-01-01

    The characteristic oscillations of the sleeping brain, spindles and slow waves, show trait-like, within-subject stability and a remarkable interindividual variability that correlates with functionally relevant measures such as memory performance and intelligence. Yet, the mechanisms underlying these

  9. 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...

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

    International Nuclear Information System (INIS)

    Hasegawa, Naoko; Yoshimura, Seiichi

    1999-01-01

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

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

    Energy Technology Data Exchange (ETDEWEB)

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

    1999-03-01

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

  12. Individual differences in episodic memory abilities predict successful prospective memory output monitoring.

    Science.gov (United States)

    Hunter Ball, B; Pitães, Margarida; Brewer, Gene A

    2018-02-07

    Output monitoring refers to memory for one's previously completed actions. In the context of prospective memory (PM) (e.g., remembering to take medication), failures of output monitoring can result in repetitions and omissions of planned actions (e.g., over- or under-medication). To be successful in output monitoring paradigms, participants must flexibly control attention to detect PM cues as well as engage controlled retrieval of previous actions whenever a particular cue is encountered. The current study examined individual differences in output monitoring abilities in a group of younger adults differing in attention control (AC) and episodic memory (EM) abilities. The results showed that AC ability uniquely predicted successful cue detection on the first presentation, whereas EM ability uniquely predicted successful output monitoring on the second presentation. The current study highlights the importance of examining external correlates of PM abilities and contributes to the growing body of research on individual differences in PM.

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

    National Research Council Canada - National Science Library

    Arvey, Richard

    1998-01-01

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

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

    Science.gov (United States)

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

    2013-05-01

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

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

    Science.gov (United States)

    Guthrie, Lisa G; Vallée-Tourangeau, Frédéric

    2018-02-03

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

  16. Consumer responses to advertising on the Internet: the effect of individual difference on ambivalence and avoidance.

    Science.gov (United States)

    Jin, Chang Hyun; Villegas, Jorge

    2007-04-01

    The purpose of this study was to understand the effect that individual characteristics have on consumer advertising processing under high- and low-interactivity circumstances on the Web. Tests on the relationship between individual differences and advertising responses form the basis of this empirical study on the Web. The results indicated that consumers have a higher tendency to avoid or experience ambivalence about Internet advertisements under low-interactivity circumstances, and attitudinal ambivalence lead to avoidance when responding to advertisements on the Internet. Personality variables are the main factors in consumer decision-making behaviors and Internet characteristics, such as levels of interactivity, can greatly influence the effectiveness of advertising in online environments. Advertising credibility could influence people's consumer attitudes, beliefs, or behaviors over time on the Web.

  17. 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.

  18. Distribution of Different Sized Ocular Surface Vessels in Diabetics and Normal Individuals.

    Science.gov (United States)

    Banaee, Touka; Pourreza, Hamidreza; Doosti, Hassan; Abrishami, Mojtaba; Ehsaei, Asieh; Basiry, Mohsen; Pourreza, Reza

    2017-01-01

    To compare the distribution of different sized vessels using digital photographs of the ocular surface of diabetic and normal individuals. In this cross-sectional study, red-free conjunctival photographs of diabetic and normal individuals, aged 30-60 years, were taken under defined conditions and analyzed using a Radon transform-based algorithm for vascular segmentation. The image areas occupied by vessels (AOV) of different diameters were calculated. The main outcome measure was the distribution curve of mean AOV of different sized vessels. Secondary outcome measures included total AOV and standard deviation (SD) of AOV of different sized vessels. Two hundred and sixty-eight diabetic patients and 297 normal (control) individuals were included, differing in age (45.50 ± 5.19 vs. 40.38 ± 6.19 years, P distribution curves of mean AOV differed between patients and controls (smaller AOV for larger vessels in patients; P distribution curve of vessels compared to controls. Presence of diabetes mellitus is associated with contraction of larger vessels in the conjunctiva. Smaller vessels dilate with diabetic retinopathy. These findings may be useful in the photographic screening of diabetes mellitus and retinopathy.

  19. Personality traits and individual differences predict threat-induced changes in postural control.

    Science.gov (United States)

    Zaback, Martin; Cleworth, Taylor W; Carpenter, Mark G; Adkin, Allan L

    2015-04-01

    This study explored whether specific personality traits and individual differences could predict changes in postural control when presented with a height-induced postural threat. Eighty-two healthy young adults completed questionnaires to assess trait anxiety, trait movement reinvestment (conscious motor processing, movement self-consciousness), physical risk-taking, and previous experience with height-related activities. Tests of static (quiet standing) and anticipatory (rise to toes) postural control were completed under low and high postural threat conditions. Personality traits and individual differences significantly predicted height-induced changes in static, but not anticipatory postural control. Individuals less prone to taking physical risks were more likely to lean further away from the platform edge and sway at higher frequencies and smaller amplitudes. Individuals more prone to conscious motor processing were more likely to lean further away from the platform edge and sway at larger amplitudes. Individuals more self-conscious about their movement appearance were more likely to sway at smaller amplitudes. Evidence is also provided that relationships between physical risk-taking and changes in static postural control are mediated through changes in fear of falling and physiological arousal. Results from this study may have indirect implications for balance assessment and treatment; however, further work exploring these factors in patient populations is necessary. Copyright © 2015 Elsevier B.V. All rights reserved.

  20. Modeling of the bipolar transistor under different pulse ionizing radiations

    Science.gov (United States)

    Antonova, A. M.; Skorobogatov, P. K.

    2017-01-01

    This paper describes a 2D model of the bipolar transistor 2T312 under gamma, X-ray and laser pulse ionizing radiations. Both the Finite Element Discretization and Semiconductor module of Comsol 5.1 are used. There is an analysis of energy deposition in this device under different radiations and the results of transient ionizing current response for some different conditions.

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

    Science.gov (United States)

    Siegler, Robert S.

    1988-01-01

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

  2. Serotonin transporter (5-HTTLPR genotype and childhood trauma are associated with individual differences in decision making

    Directory of Open Access Journals (Sweden)

    Scott F Stoltenberg

    2011-06-01

    Full Text Available The factors that influence individual differences in decision making are not yet fully characterized, but convergent evidence is accumulating that implicates serotonin (5-HT system function. Therefore, both genes and environments that influence serotonin function are good candidates for association with risky decision making. In the present study we examined associations between common polymorphisms in the serotonin transporter gene (SLC6A4; 5-HTTLPR and rs25531, the experience of childhood trauma and decision making on the Iowa Gambling Task (IGT in 391 (64.5% female healthy Caucasian adults. Homozygosity for the 5-HTTLPR L allele was associated with riskier decision making in the first block of 20 trials (i.e. decision making under ambiguity, p = .004. In addition, mean IGT performance was significantly worse in blocks 3-5 (i.e. decision making under risk, p≤ .05 for those participants who reported experiencing higher levels of childhood trauma. Our findings add to the growing evidence that genetic variation in the 5-HT system is associated with individual differences in decision making under ambiguity; and we report that the experience of childhood trauma is associated with relatively poor decision making under risk.

  3. Individual heterogeneity determines sex differences in mortality in a monogamous bird with reversed sexual dimorphism.

    Science.gov (United States)

    Colchero, Fernando; Aliaga, Alix Eva; Jones, Owen R; Conde, Dalia A

    2017-07-01

    Sex differences in mortality are pervasive in vertebrates, and usually result in shorter life spans in the larger sex, although the underlying mechanisms are still unclear. On the other hand, differences in frailty among individuals (i.e. individual heterogeneity), can play a major role in shaping demographic trajectories in wild populations. The link between these two processes has seldom been explored. We used Bayesian survival trajectory analysis to study age-specific mortality trajectories in the Eurasian sparrowhawk (Accipiter nisus), a monogamous raptor with reversed sexual size dimorphism. We tested the effect of individual heterogeneity on age-specific mortality, and the extent by which this heterogeneity was determined by average reproductive output and wing length as measures of an individual's frailty. We found that sex differences in age-specific mortality were primarily driven by the differences in individual heterogeneity between the two sexes. Females were more heterogeneous than males in their level of frailty. Thus, a larger number of females with low frailty are able to survive to older ages than males, with life expectancy for the least frail adult females reaching up to 4·23 years, while for the least frail adult males it was of 2·68 years. We found that 50% of this heterogeneity was determined by average reproductive output and wing length in both sexes. For both, individuals with high average reproductive output had also higher chances to survive. However, the effect of wing length was different between the two sexes. While larger females had higher survival, larger males had lower chances to survive. Our results contribute a novel perspective to the ongoing debate about the mechanisms that drive sex differences in vital rates in vertebrates. Although we found that variables that relate to the cost of reproduction and sexual dimorphism are at least partially involved in determining these sex differences, it is through their effect on the

  4. 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.

  5. Reexamining individual differences in women's rape avoidance behaviors.

    Science.gov (United States)

    Snyder, Jeffrey K; Fessler, Daniel M T

    2013-05-01

    A growing number of investigators explore evolutionary psychological hypotheses concerning the avoidance of rape using self-report measures of behavior. Among the most recent and most ambitious, is the work of McKibbin et al. (2011). McKibbin et al. presented evidence supporting their predictions that such behaviors would vary according to the individual's physical attractiveness, relationship status, and proximity to kin. In addition, McKibbin et al. predicted, but failed to find evidence, that age would exercise a similar influence. We question McKibbin et al.'s position on both theoretical and empirical grounds, arguing that (1) two of their predictions do not rule out alternative explanations, and (2) their key supporting findings may well be artifacts of their measurement instrument, the Rape Avoidance Inventory (RAI). Employing new empirical evidence derived from a broader sample of U.S. women, we simultaneously tested McKibbin et al.'s predictions and compared the RAI to alternative dependent measures. We found that McKibbin et al.'s substantive predictions were not supported, and suggest that there may be limits to the utility of the RAI beyond one specific demographic category.

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

    Science.gov (United States)

    Metzler-Baddeley, Claudia; Baddeley, Roland J; Jones, Derek K; Aggleton, John P; O'Sullivan, Michael J

    2013-01-01

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

  7. 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.

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

    Science.gov (United States)

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

    2011-01-01

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

  9. Neuroanatomical correlates of individual differences in social anxiety in a non-clinical population.

    Science.gov (United States)

    Tian, Xue; Hou, Xin; Wang, Kangcheng; Wei, Dongtao; Qiu, Jiang

    2016-01-01

    Socially anxious individuals are characterized as those with distorted negative self-beliefs (NSBs), which are thought to enhance reactions of social distress (emotional reactivity) and social avoidance (social functioning). However, it remains unclear whether individual differences in social distress and social avoidance are represented by differences in brain morphometry. To probe into these neural correlates, we analyzed magnetic resonance images of a sample of 130 healthy subjects and used the Connectome Computation System (CCS) to evaluate these factors. The results showed that social distress was correlated with the cortical volume of the right orbitofrontal cortex (OFC) and the subcortical volume of the left amygdala, while social avoidance was correlated with the cortical volume of the right dorsolateral prefrontal cortex (DLPFC). Additionally, loneliness might mediate the relationship between the amygdala volume and the social distress score. Our results demonstrated that social distress and social avoidance were represented by segregated cortical regions in the healthy individuals. These findings might provide a valuable basis for understanding the stable brain structures underlying individual differences in social anxiety.

  10. Are Women More Loyal Customers than Men? Gender Differences in Consumer Loyalty to Firms and Individual Service Providers

    OpenAIRE

    Melnyk, Valentina; Osselaer, Stijn; Bijmolt, Tammo

    2009-01-01

    textabstractPrevailing wisdom assumes that female consumers are more loyal than male consumers. The authors report conditions under which the reverse is found, depending on the object of customer loyalty. For example, whereas female consumers tend to be more loyal than male consumers to individuals, such as individual service providers, this difference is reversed when the object of loyalty is a group of people. The authors find a similar crossover interaction effect for loyalty to individual...

  11. Gender-Related Differences in Individuals Seeking Treatment for Kleptomania

    Science.gov (United States)

    Grant, Jon E.; Potenza, Marc N.

    2013-01-01

    Objective 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. Method From 2001 to 2007, 95 adult subjects (n=27 [28.4%] males) with DSM-IV kleptomania were assessed on sociodemographics and clinical characteristics including symptom severity, comorbidity, and functional impairment to identify gender-related differences. Results Men and women both showed substantial symptom severity and functional impairment. Compared to affected men, women with kleptomania were more likely to be married (47.1% compared to 25.9%; p=.039), have a later age at shoplifting onset (20.9 compared to 14 years; p=.001), steal household items (pdisorder (p=.017) and less likely to steal electronic goods (pdisorder (p=.018). Conclusions Kleptomania 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. PMID:18323758

  12. 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.

  13. Quantum efficiency of GaN photocathode under different illumination

    Science.gov (United States)

    Wang, Xiaohui; Chang, Benkang; Du, Yujie; Qiao, Jianliang

    2011-07-01

    GaN samples are activated by Cs/O under illumination of deuterium lamp, 300 nm monochromatic light with power of 70 μW and 300 nm monochromatic light with power of 35 μW, respectively. Photocurrent is detected before activation under illumination of deuterium lamp. Quantum efficiency (QE) is tested after activation. The results indicate that GaN activated under 300 nm monochromatic light have higher QE than that under deuterium lamp, and no obvious difference is detected between different power 300 nm monochromatic light. The photocurrent before activation inhibits the adsorption of Cs on the GaN surface, which decrease the QE of GaN.

  14. Neural correlates of individual differences in manual imitation fidelity

    Directory of Open Access Journals (Sweden)

    Lieke eBraadbaart

    2012-10-01

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

  15. Individuals exhibit consistent differences in their metabolic rates across changing thermal conditions.

    Science.gov (United States)

    Auer, Sonya K; Salin, Karine; Anderson, Graeme J; Metcalfe, Neil B

    2018-03-01

    Metabolic rate has been linked to growth, reproduction, and survival at the individual level and is thought to have far reaching consequences for the ecology and evolution of organisms. However, metabolic rates must be consistent (i.e. repeatable) over at least some portion of the lifetime in order to predict their longer-term effects on population dynamics and how they will respond to selection. Previous studies demonstrate that metabolic rates are repeatable under constant conditions but potentially less so in more variable environments. We measured the standard (=minimum) metabolic rate, maximum metabolic rate, and aerobic scope (=interval between standard and maximum rates) in juvenile brown trout (Salmo trutta) after 5weeks acclimation to each of three consecutive test temperatures (10, 13, and then 16°C) that simulated the warming conditions experienced throughout their first summer of growth. We found that metabolic rates are repeatable over a period of months under changing thermal conditions: individual trout exhibited consistent differences in all three metabolic traits across increasing temperatures. Initial among-individual differences in metabolism are thus likely to have significant consequences for fitness-related traits over key periods of their life history. Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.

  16. Individual Differences in the Cognitive Processes of Reading: I. Word Decoding.

    Science.gov (United States)

    Stanovich, Keith E.

    1982-01-01

    The importance of word decoding in accounting for individual differences in reading comprehension is discussed. Research on individual differences in the cognitive processes that mediate word decoding is reviewed. (Author)

  17. Individual differences in processing syntactic and semantic information: Looking for subpopulations

    NARCIS (Netherlands)

    van den Hazelkamp, C.|info:eu-repo/dai/nl/339459867

    2018-01-01

    Individual differences in sentence understanding exist in terms of speed, strategy and interpretation. In psycholinguistics experiments, these -sometimes small- differences are often treated as “noise” and considered meaningless. This dissertation focuses on such variation across individuals in the

  18. Individual Differences and Social Influences on the Neurobehavioral Pharmacology of Abused Drugs

    Science.gov (United States)

    Neisewander, J. L.; Kelly, T. H.

    2013-01-01

    The interaction of drugs with biologic targets is a critical area of research, particularly for the development of medications to treat substance use disorders. In addition to understanding these drug-target interactions, however, there is a need to understand more fully the psychosocial influences that moderate these interactions. The first section of this review introduces some examples from human behavioral pharmacology that illustrate the clinical importance of this research. The second section covers preclinical evidence to characterize some of the key individual differences that alter drug sensitivity and abuse vulnerability, related primarily to differences in response to novelty and impulsivity. Evidence is presented to indicate that critical neuropharmacological mechanisms associated with these individual differences involve integrated neurocircuits underlying stress, reward, and behavioral inhibitory processes. The third section covers social influences on drug abuse vulnerability, including effects experienced during infancy, adolescence, and young adulthood, such as maternal separation, housing conditions, and social interactions (defeat, play, and social rank). Some of the same neurocircuits involved in individual differences also are altered by social influences, although the precise neurochemical and cellular mechanisms involved remain to be elucidated fully. Finally, some speculation is offered about the implications of this research for the prevention and treatment of substance abuse. PMID:23343975

  19. Are implicit self-esteem measures valid for assessing individual and cultural differences?

    Science.gov (United States)

    Falk, Carl F; Heine, Steven J; Takemura, Kosuke; Zhang, Cathy X J; Hsu, Chih-Wei

    2015-02-01

    Our research utilized two popular theoretical conceptualizations of implicit self-esteem: 1) implicit self-esteem as a global automatic reaction to the self; and 2) implicit self-esteem as a context/domain specific construct. Under this framework, we present an extensive search for implicit self-esteem measure validity among different cultural groups (Study 1) and under several experimental manipulations (Study 2). In Study 1, Euro-Canadians (N = 107), Asian-Canadians (N = 187), and Japanese (N = 112) completed a battery of implicit self-esteem, explicit self-esteem, and criterion measures. Included implicit self-esteem measures were either popular or provided methodological improvements upon older methods. Criterion measures were sampled from previous research on implicit self-esteem and included self-report and independent ratings. In Study 2, Americans (N = 582) completed a shorter battery of these same types of measures under either a control condition, an explicit prime meant to activate the self-concept in a particular context, or prime meant to activate self-competence related implicit attitudes. Across both studies, explicit self-esteem measures far outperformed implicit self-esteem measures in all cultural groups and under all experimental manipulations. Implicit self-esteem measures are not valid for individual or cross-cultural comparisons. We speculate that individuals may not form implicit associations with the self as an attitudinal object. © 2013 Wiley Periodicals, Inc.

  20. 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.

  1. 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.

  2. Shifting between mental sets: An individual differences approach to commonalities and differences of task switching components.

    Science.gov (United States)

    von Bastian, Claudia C; Druey, Michel D

    2017-09-01

    Switching between mental sets has been extensively investigated in both experimental and individual differences research using a wide range of task-switch paradigms. However, it is yet unclear whether these different tasks measure a unitary shifting ability or reflect different facets thereof. In this study, 20 task pairs were administered to 119 young adults to assess 5 proposed components of mental set shifting: switching between judgments, stimulus dimensions, stimulus-response mappings, response sets, and stimulus sets. Modeling latent factors for each of the components revealed that a model with 5 separate yet mostly correlated factors fit the data best. In this model, the components most strongly related to the other latent factors were stimulus-response mapping shifting and, to a lesser degree, response set shifting. In addition, both factors were statistically indistinguishable from a second-order general shifting factor. In contrast, shifting between judgments as well as stimulus dimensions consistently required separate factors and could, hence, not fully be accounted for by the general shifting factor. Finally, shifting between stimulus sets was unrelated to any other shifting component but mapping shifting. We conclude that tasks assessing shifting between mappings are most adequate to assess general shifting ability. In contrast, shifting between stimulus sets (e.g., as in the Trail Making Test) probably reflects shifts in visual attention rather than executive shifting ability. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

  3. Neural processes underlying cultural differences in cognitive persistence.

    Science.gov (United States)

    Telzer, Eva H; Qu, Yang; Lin, Lynda C

    2017-08-01

    Self-improvement motivation, which occurs when individuals seek to improve upon their competence by gaining new knowledge and improving upon their skills, is critical for cognitive, social, and educational adjustment. While many studies have delineated the neural mechanisms supporting extrinsic motivation induced by monetary rewards, less work has examined the neural processes that support intrinsically motivated behaviors, such as self-improvement motivation. Because cultural groups traditionally vary in terms of their self-improvement motivation, we examined cultural differences in the behavioral and neural processes underlying motivated behaviors during cognitive persistence in the absence of extrinsic rewards. In Study 1, 71 American (47 females, M=19.68 years) and 68 Chinese (38 females, M=19.37 years) students completed a behavioral cognitive control task that required cognitive persistence across time. In Study 2, 14 American and 15 Chinese students completed the same cognitive persistence task during an fMRI scan. Across both studies, American students showed significant declines in cognitive performance across time, whereas Chinese participants demonstrated effective cognitive persistence. These behavioral effects were explained by cultural differences in self-improvement motivation and paralleled by increasing activation and functional coupling between the inferior frontal gyrus (IFG) and ventral striatum (VS) across the task among Chinese participants, neural activation and coupling that remained low in American participants. These findings suggest a potential neural mechanism by which the VS and IFG work in concert to promote cognitive persistence in the absence of extrinsic rewards. Thus, frontostriatal circuitry may be a neurobiological signal representing intrinsic motivation for self-improvement that serves an adaptive function, increasing Chinese students' motivation to engage in cognitive persistence. Copyright © 2017 Elsevier Inc. All rights

  4. Individual Differences in Frequency of Inner Speech: Differential Relations with Cognitive and Non-cognitive Factors

    Directory of Open Access Journals (Sweden)

    Xuezhu Ren

    2016-11-01

    Full Text Available Inner speech plays a crucial role in behavioral regulation and the use of inner speech is very common among adults. However, less is known about individual differences in the frequency of inner speech use and about the underlying processes that may explain why people exhibit individual differences in the frequency of inner speech use. This study was conducted to investigate how individual differences in the frequency of inner speech use are related to cognitive and non-cognitive factors. Four functions of inner speech including self-criticism, self-reinforcement, self-management, and social assessment measured by an adapted version of Brinthaupt’s Self-Talk Scale were examined. The cognitive factors that were considered included executive functioning and complex reasoning and the non-cognitive factors consisted of trait anxiety and impulsivity. Data were collected from a large Chinese sample. Results revealed that anxiety and impulsivity were mainly related to the frequency of the affective function of inner speech (self-criticism and self-reinforcement and executive functions and complex reasoning were mainly related to the frequency of the cognitive, self-regulatory function of inner speech (self-management.

  5. 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. Copyright © 2015 Society for the Study of School Psychology. Published by Elsevier Ltd. All rights reserved.

  6. Beauty and the brain: culture, history and individual differences in aesthetic appreciation

    Science.gov (United States)

    Jacobsen, Thomas

    2010-01-01

    Human aesthetic processing entails the sensation-based evaluation of an entity with respect to concepts like beauty, harmony or well-formedness. Aesthetic appreciation has many determinants ranging from evolutionary, anatomical or physiological constraints to influences of culture, history and individual differences. There are a vast number of dynamically configured neural networks underlying these multifaceted processes of aesthetic appreciation. In the current challenge of successfully bridging art and science, aesthetics and neuroanatomy, the neuro-cognitive psychology of aesthetics can approach this complex topic using a framework that postulates several perspectives, which are not mutually exclusive. In this empirical approach, objective physiological data from event-related brain potentials and functional magnetic resonance imaging are combined with subjective, individual self-reports. PMID:19929909

  7. Individual differences in cortisol stress response predict increases in voice pitch during exam stress.

    Science.gov (United States)

    Pisanski, Katarzyna; Nowak, Judyta; Sorokowski, Piotr

    2016-09-01

    Despite a long history of empirical research, the potential vocal markers of stress remain unclear. Previous studies examining speech under stress most consistently report an increase in voice pitch (the acoustic correlate of fundamental frequency, F0), however numerous studies have failed to replicate this finding. In the present study we tested the prediction that these inconsistencies are tied to variation in the severity of the stress response, wherein voice changes may be observed predominantly among individuals who show a cortisol stress response (i.e., an increase in free cortisol levels) above a critical threshold. Voice recordings and saliva samples were collected from university psychology students at baseline and again immediately prior to an oral examination. Voice recordings included both read and spontaneous speech, from which we measured mean, minimum, maximum, and the standard deviation in F0. We observed an increase in mean and minimum F0 under stress in both read and spontaneous speech, whereas maximum F0 and its standard deviation showed no systematic changes under stress. Our results confirmed that free cortisol levels increased by an average of 74% (ranging from 0 to 270%) under stress. Critically, increases in cortisol concentrations significantly predicted increases in mean F0 under stress for both speech types, but did not predict variation in F0 at baseline. On average, stress-induced increases in voice pitch occurred only when free cortisol levels more than doubled their baseline concentrations. Our results suggest that researchers examining speech under stress should control for individual differences in the magnitude of the stress response. Copyright © 2016 Elsevier Inc. All rights reserved.

  8. Compressions of electrorheological fluids under different initial gap distances.

    Science.gov (United States)

    Tian, Yu; Wen, Shizhu; Meng, Yonggang

    2003-05-01

    Compressions of electrorheological (ER) fluids have been carried out under different initial gap distances and different applied voltages. The nominal yield stresses of the compressed ER fluid under different conditions, according to the mechanics of compressing continuous fluids considering the yield stress of the plastic fluid, have been calculated. Curves of nominal yield stress under different applied voltages at an initial gap distance of 4 mm overlapped well and were shown to be proportional to the square of the external electric field and agree well with the traditional description. With the decrease of the initial gap distance, the difference between the nominal yield stress curves increased. The gap distance effect on the compression of ER fluids could not be explained by the traditional description based on the Bingham model and the continuous media theory. An explanation based on the mechanics of particle chain is proposed to describe the gap distance effect on the compression of ER fluids.

  9. Chemical dosimetry techniques for various applications under different geometries

    CERN Document Server

    Gupta, B L; Narayan, G R; Nilekani, S R

    2000-01-01

    This paper gives the results of dosimetry for various applications under different geometrical arrangements. These applications include: gamma chambers, blood irradiators, radiotherapy using both sup 6 sup 0 Co and accelerators, animal irradiations with different types of radiation sources, fluid irradiators for sludge and rubber latex and industrial electron irradiators. The dosimeters used were Fricke, FBX and alanine/glutamine (spectrophotometric readout).

  10. Individual differences in brain structure underpin empathizing-systemizing cognitive styles in male adults.

    Science.gov (United States)

    Lai, Meng-Chuan; Lombardo, Michael V; Chakrabarti, Bhismadev; Ecker, Christine; Sadek, Susan A; Wheelwright, Sally J; Murphy, Declan G M; Suckling, John; Bullmore, Edward T; Baron-Cohen, Simon

    2012-07-16

    Individual differences in cognitive style can be characterized along two dimensions: 'systemizing' (S, the drive to analyze or build 'rule-based' systems) and 'empathizing' (E, the drive to identify another's mental state and respond to this with an appropriate emotion). Discrepancies between these two dimensions in one direction (S>E) or the other (E>S) are associated with sex differences in cognition: on average more males show an S>E cognitive style, while on average more females show an E>S profile. The neurobiological basis of these different profiles remains unknown. Since individuals may be typical or atypical for their sex, it is important to move away from the study of sex differences and towards the study of differences in cognitive style. Using structural magnetic resonance imaging we examined how neuroanatomy varies as a function of the discrepancy between E and S in 88 adult males from the general population. Selecting just males allows us to study discrepant E-S profiles in a pure way, unconfounded by other factors related to sex and gender. An increasing S>E profile was associated with increased gray matter volume in cingulate and dorsal medial prefrontal areas which have been implicated in processes related to cognitive control, monitoring, error detection, and probabilistic inference. An increasing E>S profile was associated with larger hypothalamic and ventral basal ganglia regions which have been implicated in neuroendocrine control, motivation and reward. These results suggest an underlying neuroanatomical basis linked to the discrepancy between these two important dimensions of individual differences in cognitive style. Copyright © 2012 Elsevier Inc. All rights reserved.

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

    Science.gov (United States)

    Maddox, George L.; Douglass, Elizabeth B.

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

  12. Individual differences in adult foreign language learning: the mediating effect of metalinguistic awareness.

    Science.gov (United States)

    Brooks, Patricia J; Kempe, Vera

    2013-02-01

    In this study, we sought to identify cognitive predictors of individual differences in adult foreign-language learning and to test whether metalinguistic awareness mediated the observed relationships. Using a miniature language-learning paradigm, adults (N = 77) learned Russian vocabulary and grammar (gender agreement and case marking) over six 1-h sessions, completing tasks that encouraged attention to phrases without explicitly teaching grammatical rules. The participants' ability to describe the Russian gender and case-marking patterns mediated the effects of nonverbal intelligence and auditory sequence learning on grammar learning and generalization. Hence, even under implicit-learning conditions, individual differences stemmed from explicit metalinguistic awareness of the underlying grammar, which, in turn, was linked to nonverbal intelligence and auditory sequence learning. Prior knowledge of languages with grammatical gender (predominantly Spanish) predicted learning of gender agreement. Transfer of knowledge of gender from other languages to Russian was not mediated by awareness, which suggests that transfer operates through an implicit process akin to structural priming.

  13. The contribution of developmental experience vs. condition to life history, trait variation and individual differences.

    Science.gov (United States)

    DiRienzo, Nicholas; Montiglio, Pierre-Olivier

    2016-07-01

    1. Developmental experience, for example food abundance during juvenile stages, is known to affect life history and behaviour. However, the life history and behavioural consequences of developmental experience have rarely been studied in concert. As a result, it is still unclear whether developmental experience affects behaviour through changes in life history, or independently of it. 2. The effect of developmental experience on life history and behaviour may also be masked or affected by individual condition during adulthood. Thus, it is critical to tease apart the effects of developmental experience and current individual condition on life history and behaviour. 3. In this study, we manipulated food abundance during development in the western black widow spider, Latrodectus hesperus, by rearing spiders on either a restricted or ad lib diet. We separated developmental from condition-dependent effects by assaying adult foraging behaviour (tendency to attack prey and to stay on out of the refuge following an attack) and web structure multiple times under different levels of satiation following different developmental treatments. 4. Spiders reared under food restriction matured slower and at a smaller size than spiders reared in ad lib conditions. Spiders reared on a restricted diet were more aggressive towards prey and built webs structured for prey capture, while spiders reared on an ad lib diet were less aggressive and built safer webs. Developmental treatment affected which traits were plastic as adults: restricted spiders built safer webs when their adult condition increased, while ad lib spiders reduced their aggression when their adult condition increased. The amount of individual variation in behaviour and web structure varied with developmental treatment. Spiders reared on a restricted diet exhibited consistent variation in all aspects of foraging behaviour and web structure, while spiders reared on an ad lib diet exhibited consistent individual variation in

  14. 77 FR 14304 - Fisheries of the Exclusive Economic Zone Off Alaska; Sablefish Managed Under the Individual...

    Science.gov (United States)

    2012-03-09

    ... DEPARTMENT OF COMMERCE National Oceanic and Atmospheric Administration 50 CFR Part 679 [Docket Nos. 101126522-0640-02 and 1112113751-2102-02] RIN 0648-XB039 Fisheries of the Exclusive Economic Zone Off Alaska; Sablefish Managed Under the Individual Fishing Quota Program AGENCY: National Marine Fisheries Service (NMFS...

  15. 75 FR 11471 - Fisheries of the Exclusive Economic Zone Off Alaska; Sablefish Managed Under the Individual...

    Science.gov (United States)

    2010-03-11

    ... DEPARTMENT OF COMMERCE National Oceanic and Atmospheric Administration 50 CFR Part 679 [Docket No. 0910131362-0087-02 and 0910131363-0087-02] RIN 0648-XV03 Fisheries of the Exclusive Economic Zone Off Alaska; Sablefish Managed Under the Individual Fishing Quota Program AGENCY: National Marine Fisheries Service (NMFS...

  16. 76 FR 11161 - Fisheries of the Exclusive Economic Zone Off Alaska; Sablefish Managed Under the Individual...

    Science.gov (United States)

    2011-03-01

    ... DEPARTMENT OF COMMERCE National Oceanic and Atmospheric Administration 50 CFR Part 679 [Docket Nos. 0910131362-0087-02 and 0910131363-0087-02] RIN 0648-XA256 Fisheries of the Exclusive Economic Zone Off Alaska; Sablefish Managed Under the Individual Fishing Quota Program AGENCY: National Marine Fisheries Service (NMFS...

  17. 78 FR 16617 - Fisheries of the Exclusive Economic Zone Off Alaska; Sablefish Managed Under the Individual...

    Science.gov (United States)

    2013-03-18

    ... DEPARTMENT OF COMMERCE National Oceanic and Atmospheric Administration 50 CFR Part 679 [Docket No. 111207737-2141-02 and 1112113751-2102-02] RIN 0648-XC569 Fisheries of the Exclusive Economic Zone Off Alaska; Sablefish Managed Under the Individual Fishing Quota Program AGENCY: National Marine Fisheries Service (NMFS...

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

    National Research Council Canada - National Science Library

    Doane, Stephanie

    2004-01-01

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

  19. Fiscal Policy and Welfare under Different Exchange Rate Regimes

    DEFF Research Database (Denmark)

    Østrup, Finn

    , and secondbecause the government's inclination to expand government spending is affectedby inflation which depends on the exchange rate regime. At low rates of inflation,the government is inclined to set a higher level of government spending under afixed exchange rate regime than under a floating exchange rate...... a representativeindividual's utility, it is demonstrated that there are differences betweenexchange rate regimes with respect to the level of government spending. Thesedifferences arise first because a rise in government spending affects macroeconomicvariables differently under different exchange rate regimes...... regime in whichthe monetary authority optimises preferences which include an employment targetand an inflation target. As government spending affects the representativeindividual's utility, the choice of exchange rate regime has an impact on welfare.Keywords: exchange rate regimes; fiscal policy...

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

    Science.gov (United States)

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

    2016-06-01

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

  1. Surface Hardness of Resin Cement Polymerized under Different Ceramic Materials

    OpenAIRE

    Kesrak, Pimmada; Leevailoj, Chalermpol

    2012-01-01

    Objectives. To evaluate the surface hardness of two light-cured resin cements polymerized under different ceramic discs. Methods. 40 experimental groups of 2 light-cured resin cement specimens (Variolink Veneer and NX3) were prepared and polymerized under 5 different ceramic discs (IPS e.max Press HT, LT, MO, HO, and Cercon) of 4 thicknesses (0.5, 1.0, 1.5, and 2.0 mm), Those directly activated of both resin cements were used as control. After light activation and 3 7 ∘ C storage in an incuba...

  2. Breast cancer under age 40: a different approach.

    Science.gov (United States)

    Ribnikar, D; Ribeiro, J M; Pinto, D; Sousa, B; Pinto, A C; Gomes, E; Moser, E C; Cardoso, M J; Cardoso, F

    2015-04-01

    Breast cancer (BC) under age 40 is a complex disease to manage due to the additionally fertility-related factors to be taken in consideration. More than 90% of young patients with BC are symptomatic. Womenmanagement strategies for every individual patient with BC before the start of any therapy including surgery. This applies to both early (early breast cancer (EBC)) and advanced (advanced breast cancer (ABC)) disease, before the start of any therapy. Mastectomy even in young patients confers no overall survival advantage when compared to breast-conserving treatment (BCT), followed by radiotherapy. Regarding axillary approach, indications are identical to other age groups. Young age is one of the most important risk factors for local recurrence after both breast-conserving surgery (BCS) and mastectomy, associated with a higher risk of distant metastasis and death. Radiation after BCS reduces local recurrence from 19.5 to 10.2% in BC patients 40 years and younger. The indications for and the choice of systemic treatment for invasive BC (both early and advanced disease) should not be based on age alone but driven by the biological characteristics of the individual tumor (including hormone receptor status, human epidermal growth factor receptor 2 (HER-2) status, grade, and proliferative activity), disease stage, and patient's comorbidities. Recommendations regarding the use of genomic profiles such as MammaPrint, Oncotype Dx, and Genomic grade index in young women are similar to the general BC population. Especially in the metastatic setting, patient preferences should always be taken into account, as the disease is incurable. The best strategy for these patients is the inclusion into well-designed, independent, prospective randomized clinical trials. Metastatic disease should always be biopsied whenever feasible for histological confirmation and reassessment of biology. Endocrine therapy is the preferred option for hormone receptor-positive disease (HR+ve), even in

  3. Individual differences in the coming out process for gay men: implications for theoretical models.

    Science.gov (United States)

    McDonald, G J

    1982-01-01

    One hundred ninety-nine self-defined homosexual males were asked about the ages at which milestone events occurred in the coming out process (i.e., initial awareness of same-sex attractions, same-sex acts, self-designation as homosexual, initial involvement in a long-term relationship, self-disclosures to significant others, and acquiring a positive gay identity). Overall findings indicated that an orderly developmental sequence underlies the coming out process; however, not all subjects progressed in a predictable fashion from an awareness of same-sex feelings through behavior to eventual self-labelling, self-disclosure, and final stabilization of a positive gay identity. A number of individual differences emerged: 18% of the sample labelled themselves "homosexual" in the absence of any overt same-sex sexual experience; 22% arrived at homosexual self-definitions while participating in a long-term relationship with another man; 23% adopted homosexual self-definitions only after involvement in such a relationship. Fifteen percent of the respondents indicated that they had not acquired a positive gay identity (i.e., were not glad to be gay). These individuals differed from the remainder of the sample on a number of significant measures reflective of psychological health. Significant differences were also found among three cohort groups with respect to age at occurrence of particular milestone events. Findings from the present investigation were explored in relation to both the theoretical conceptions and available empirical data concerned with homosexual identity formation.

  4. Near-infrared spectroscopy can detect differences in vascular responsiveness to a hyperglycaemic challenge in individuals with obesity compared to normal-weight individuals.

    Science.gov (United States)

    Soares, Rogério Nogueira; Reimer, Raylene A; Alenezi, Zaid; Doyle-Baker, Patricia K; Murias, Juan Manuel

    2018-01-01

    To examine whether the near-infrared spectroscopy combined with vascular occlusion test technique could detect differences in vascular responsiveness during hyperglycaemia between normal-weight individuals and individuals with obesity. A total of 16 normal-weight individuals (body mass index, 21.3 ± 1.7 kg/m 2 ) and 13 individuals with obesity (body mass index, 34.4 ± 2.0 kg/m 2 ) were submitted to five vascular occlusion tests (Pre, 30, 60, 90 and 120 min after glucose challenge). Vascular responsiveness was determined by the Slope 2 (Slope 2 StO 2 ) and the area under the curve (StO 2AUC ) of oxygen saturation derived from near-infrared spectroscopy-vascular occlusion test. The Slope 2 StO 2 increased from 1.07 ± 0.16%/s (Pre) to 1.53 ± 0.21%/s at 90 min ( p obese it increased from 0.71 ± 0.09%/s (Pre) to 0.92 ± 0.14%/s at 60 min ( p obesity. Near-infrared spectroscopy-vascular occlusion test technique was capable of detecting differences in vascular responsiveness during hyperglycaemia between normal-weight individuals and individuals with obesity.

  5. Fiscal Policy and Welfare under Different Exchange Rate Regimes

    DEFF Research Database (Denmark)

    Østrup, Finn

    The article analyses how government spending is determined under differentexchange rate regimes in the context of a small open economy. Assumingnominal wage contracts which last for one period and assuming a benevolentgovernment which determines government spending to optimise a representativeind......The article analyses how government spending is determined under differentexchange rate regimes in the context of a small open economy. Assumingnominal wage contracts which last for one period and assuming a benevolentgovernment which determines government spending to optimise...... a representativeindividual's utility, it is demonstrated that there are differences betweenexchange rate regimes with respect to the level of government spending. Thesedifferences arise first because a rise in government spending affects macroeconomicvariables differently under different exchange rate regimes......, and secondbecause the government's inclination to expand government spending is affectedby inflation which depends on the exchange rate regime. At low rates of inflation,the government is inclined to set a higher level of government spending under afixed exchange rate regime than under a floating exchange rate...

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

    Science.gov (United States)

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

    2013-01-01

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

  7. 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.

  8. 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...

  9. Production Of Some Virulence Factors Under Different Growth ...

    African Journals Online (AJOL)

    The production of some virulence factors under different growth conditions and antibiotic susceptbility pattern of Aeromonas hydrophila were investigated in this sudy. The virulence actors tested on the isolates included haemolytic activity, exopolysaccharide (capsule) and toxin production. Other cell property evaluated was ...

  10. Changes in erythrocyte ATPase activity under different pathological ...

    African Journals Online (AJOL)

    Changes in erythrocyte ATPase activity under different pathological conditions. Ali A Kherd, Nawal Helmi, Khadijah Saeed Balamash, Taha A Kumosani, Shareefa A AL-Ghamdi, Qari M, Etimad A Huwait, Soonham S Yaghmoor, Alaama Nabil, Maryam A AL-Ghamdi, Said S Moselhy ...

  11. Dam break flood wave under different reservoir's capacities and ...

    Indian Academy of Sciences (India)

    Dam failure has been the subject of many hydraulic engineering studies due to its complicated physics with many uncertainties involved and the potential to cause many ... This paper presents an experimental study on instantaneous dam failure flood under different reservoir's capacities and lengths in which the side slopes ...

  12. Object Construction and Imitation under Differing Conditions of Rearing

    Science.gov (United States)

    Paraskevopoulos, John; Hunt, J. McV.

    1971-01-01

    Compares the ages at which infants living under different conditions in two orphanges in Athens, Greece achieve levels of object construction and imitation, both verbal and gestural. Home-reared infants of the same age range were also examined using two of the Uzgiris-Hunt Ordinal Scales of Infant Psychological Development. (WY)

  13. Spatial patterns of encroaching shrub species under different ...

    African Journals Online (AJOL)

    ... in Middelburg (Eastern Cape, South Africa) coexist and partition space under different grazing regimes (viz. continuous rest, and continuous, summer and winter grazing). We used point-pattern analysis to assess the spatial ecology of these species. We also used an index of integration (mingling index), where low values ...

  14. Growth Performance of Grain Amaranth under Different Nursery Soil ...

    African Journals Online (AJOL)

    The growth performance of grain amaranth under different soil nursery media was studied in Owerri, South Eastern Nigeria. The experiment was a completely randomized design (CRD) experiment with five replications. The experiment was carried out at the teaching and research farm of the department of Agricultural ...

  15. Investigating the Nature of GxE Interaction under Different ...

    African Journals Online (AJOL)

    for this study were from Intermediate to Late Hybrid Trials (ILHT) conducted in ... This phenomenon, referred to as COI, introduces a degree of uncertainty into the ... Investigating the Nature of GxE Interaction under Different Management Systems [3]. Materials and Methods. Setup of the trial. The number of trial sites used for ...

  16. Provincial responsibility for carbon emissions in China under different principles

    International Nuclear Information System (INIS)

    Zhang, Youguo

    2015-01-01

    By applying a multi-regional input–output model, the study compares the provincial responsibility for carbon emissions and provincial carbon multipliers in China under seven responsibility-allocating principles, including three basic principles, the production, income and consumption principles, and four shared responsibility principles, the income-weighted, consumption weighted, comprehensive, and weighted comprehensive principles. Empirical results indicate that carbon multipliers of provinces under these principles are significantly different from one another. The carbon multipliers of provinces with higher ratios of carbon intensive sectors in their outputs are also larger. At the same time, the carbon multipliers of the same sector in the provinces are significantly different from one another. Changing the principle causes significant changes in the responsibility for carbon emissions of some provinces, but only slight changes in the responsibilities of some other provinces. However, the responsibilities of provinces with large economic sizes (output) are always the largest, whereas provinces with the smallest economic sizes are always the smallest regardless of the principles. Further, this study proposes a series of regional policies for carbon mitigation according to provincial carbon multipliers and responsibility allocation features under the different principles. - Highlights: • We link regional environmental responsibility to seven benefit principles. • We analyze provincial responsibility for carbon emissions in China. • We also report provincial carbon multipliers under different principles. • We compare the seven principles from the regional perspective. • Policy implications of the study are discussed.

  17. Age differences in the underlying mechanisms of stereotype threat effects.

    Science.gov (United States)

    Popham, Lauren E; Hess, Thomas M

    2015-03-01

    The goals of the present study were to (a) examine whether age differences exist in the mechanisms underlying stereotype threat effects on cognitive performance and (b) examine whether emotion regulation abilities may buffer against threat effects on performance. Older and younger adults were exposed to positive or negative age-relevant stereotypes, allowing us to examine the impact of threat on regulatory focus and working memory. Self-reported emotion regulation measures were completed prior to the session. Older adults' performance under threat suggested a prevention-focused approach to the task, indexed by increased accuracy and reduced speed. The same pattern was observed in younger adults, but the effects were not as strong. Age differences emerged when examining the availability of working memory resources under threat, with young adults showing decrements, whereas older adults did not. Emotion regulation abilities moderated threat effects in young adults but not in older adults. The results provide support for the notion that stereotype threat may lead to underperformance through somewhat different pathways in older and younger adults. Future research should further examine whether the underlying reason for this age difference is rooted in age-related improvements in emotion regulation. © The Author 2013. Published by Oxford University Press on behalf of The Gerontological Society of America. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  18. Rainwater use by cotton under different irrigation systems

    Science.gov (United States)

    Rainwater Use by Cotton Under Different Irrigation Systems To increase the efficiency by which agronomic crops use water input from both irrigation and rain during the growing season requires quantifying the proportion of rainfall used by the crop for any rain event. The rainfall pattern in the Texa...

  19. Individual response differences in spider phobia: comparing phobic and non-phobic women of different reactivity levels.

    Science.gov (United States)

    Knopf, Kerstin; Pössel, Patrick

    2009-01-01

    In contrast to previous stress research, studies concerning phobic disorders have never systematically investigated individual response differences between phobic participants integrating numerous different response measures. The aim of this article is to clarify the existence of significant individual response differences in psychophysiological responses (e.g., heart rate, skin conductance responses (SCR), corrugator, cortisol), subjective ratings (e.g., valence, arousal), and avoidance behavior in 46 spider phobic and 44 non-phobic women when exposed to 20 phobic and 20 neutral pictures. Previous studies that did not attend to individual response differences showed that, during phobic stimulation, phobic individuals have increased psychophysiological responses (heart rate, SCR, and corrugator responses), more negative valence rating, and more subjective arousal than non-phobic individuals. These results were confirmed by our data. With regard to individual response uniqueness, 1/3-2/3 of spider-phobic women with low responsiveness in heart rate, cortisol, and avoidance behavior were indistinguishable from non-phobic women during phobic stimulation. With SCR, corrugator EMG, and subjective ratings, no individual response uniqueness was found. Based on the findings, exposure therapy might be improved by tailoring interventions to individuals with a therapeutic focus on those psychophysiological measures that show the highest individual responsivity.

  20. Individual differences in the effects of chronic stress on memory: behavioral and neurochemical correlates of resiliency.

    Science.gov (United States)

    Sweis, B M; Veverka, K K; Dhillon, E S; Urban, J H; Lucas, L R

    2013-08-29

    Chronic stress has been shown to impair memory, however, the extent to which memory can be impaired is often variable across individuals. Predisposed differences in particular traits, such as anxiety, may reveal underlying neurobiological mechanisms that could be driving individual differences in sensitivity to stress and, thus, stress resiliency. Such pre-morbid characteristics may serve as early indicators of susceptibility to stress. Neuropeptide Y (NPY) and enkephalin (ENK) are neurochemical messengers of interest implicated in modulating anxiety and motivation circuitry; however, little is known about how these neuropeptides interact with stress resiliency and memory. In this experiment, adult male rats were appetitively trained to locate sugar rewards in a motivation-based spatial memory task before undergoing repeated immobilization stress and then being tested for memory retention. Anxiety-related behaviors, among other characteristics, were monitored longitudinally. Results indicated that stressed animals which showed little to no impairments in memory post-stress (i.e., the more stress-resilient individuals) exhibited lower anxiety levels prior to stress when compared to stressed animals that showed large deficits in memory (i.e., the more stress-susceptible individuals). Interestingly, all stressed animals, regardless of memory change, showed reduced body weight gain as well as thymic involution, suggesting that the effects of stress on metabolism and the immune system were dissociated from the effects of stress on higher cognition, and that stress resiliency seems to be domain-specific rather than a global characteristic within an individual. Neurochemical analyses revealed that NPY in the hypothalamus and amygdala and ENK in the nucleus accumbens were modulated differentially between stress-resilient and stress-susceptible individuals, with elevated expression of these neuropeptides fostering anxiolytic and pro-motivation function, thus driving

  1. Individual differences in sleep timing relate to Melanopsin-based phototransduction in healthy adolescents and young adults

    NARCIS (Netherlands)

    Van Der Meijden, Wisse P.; Van Someren, Jamie L.; Te Lindert, Bart H W; Bruijel, Jessica; Van Oosterhout, Floor; Coppens, Joris E.; Kalsbeek, Andries; Cajochen, Christian; Bourgin, Patrice; Van Someren, Eus J W

    2016-01-01

    Study Objectives: Individual differences in sleep timing have been widely recognized and are of particular relevance in adolescents and young adults who often show mild to severely delayed sleep. The biological mechanisms underlying the between-subject variance remain to be determined. Recent human

  2. Individual Differences in Sleep Timing Relate to Melanopsin-Based Phototransduction in Healthy Adolescents and Young Adults

    NARCIS (Netherlands)

    van der Meijden, Wisse P; Van Someren, Jamie L; Te Lindert, Bart H W; Bruijel, Jessica; van Oosterhout, Floor; Coppens, Joris E; Kalsbeek, A.; Cajochen, Christian; Bourgin, Patrice; Van Someren, Eus J W

    2016-01-01

    STUDY OBJECTIVES: Individual differences in sleep timing have been widely recognized and are of particular relevance in adolescents and young adults who often show mild to severely delayed sleep. The biological mechanisms underlying the between-subject variance remain to be determined. Recent human

  3. Individual Differences in Sleep Timing Relate to Melanopsin-Based Phototransduction in Healthy Adolescents and Young Adults

    NARCIS (Netherlands)

    van der Meijden, Wisse P.; van Someren, Jamie L.; te Lindert, Bart H. W.; Bruijel, Jessica; van Oosterhout, Floor; Coppens, Joris E.; Kalsbeek, Andries; Cajochen, Christian; Bourgin, Patrice; van Someren, Eus J. W.

    2016-01-01

    Individual differences in sleep timing have been widely recognized and are of particular relevance in adolescents and young adults who often show mild to severely delayed sleep. The biological mechanisms underlying the between-subject variance remain to be determined. Recent human genetics studies

  4. Women's Race-and Sex-Based Social Attitudes: An Individual Differences Perspective

    Directory of Open Access Journals (Sweden)

    Peter K. Jonason

    2017-05-01

    Full Text Available How do individual differences in personality and sexuality relate to social attitudes? We contend that personality traits and sexual orientation are descriptions of underlying biases (e.g., perceptual that exert top-down influences into all of life's domains including social attitudes. The present study (N=200 women examined individual differences in sex-based and race-based social attitudes as a function of the Big Five traits, the Dark Triad traits, and sexual orientation. We found that affiliative-based motivations in the form of agreeableness, openness, and narcissism predicted the desire and tendency to affiliate with other women. We also found fear-based (i.e., neuroticism and entitlement-based (i.e., narcissism traits were associated with efforts towards political action for gender equality. We found a "go-along" disposition (i.e., agreeableness and openness was associated with greater endorsement of traditional gender roles. We replicated associations between the Big Five traits (i.e., openness and agreeableness and race-based social attitudes. Uniquely, Machiavellianism was associated with more race-based social attitudes but with diminished endorsement of traditional gender roles. And last, we suggest that experienced discrimination among bisexual women may lead them to be less likely to hold both undesirable race-based and sex-based social attitudes.

  5. The functional and structural neural basis of individual differences in loss aversion.

    Science.gov (United States)

    Canessa, Nicola; Crespi, Chiara; Motterlini, Matteo; Baud-Bovy, Gabriel; Chierchia, Gabriele; Pantaleo, Giuseppe; Tettamanti, Marco; Cappa, Stefano F

    2013-09-04

    Decision making under risk entails the anticipation of prospective outcomes, typically leading to the greater sensitivity to losses than gains known as loss aversion. Previous studies on the neural bases of choice-outcome anticipation and loss aversion provided inconsistent results, showing either bidirectional mesolimbic responses of activation for gains and deactivation for losses, or a specific amygdala involvement in processing losses. Here we focused on loss aversion with the aim to address interindividual differences in the neural bases of choice-outcome anticipation. Fifty-six healthy human participants accepted or rejected 104 mixed gambles offering equal (50%) chances of gaining or losing different amounts of money while their brain activity was measured with functional magnetic resonance imaging (fMRI). We report both bidirectional and gain/loss-specific responses while evaluating risky gambles, with amygdala and posterior insula specifically tracking the magnitude of potential losses. At the individual level, loss aversion was reflected both in limbic fMRI responses and in gray matter volume in a structural amygdala-thalamus-striatum network, in which the volume of the "output" centromedial amygdala nuclei mediating avoidance behavior was negatively correlated with monetary performance. We conclude that outcome anticipation and ensuing loss aversion involve multiple neural systems, showing functional and structural individual variability directly related to the actual financial outcomes of choices. By supporting the simultaneous involvement of both appetitive and aversive processing in economic decision making, these results contribute to the interpretation of existing inconsistencies on the neural bases of anticipating choice outcomes.

  6. Who Sees Human? The Stability and Importance of Individual Differences in Anthropomorphism.

    Science.gov (United States)

    Waytz, Adam; Cacioppo, John; Epley, Nicholas

    2010-05-01

    Anthropomorphism is a far-reaching phenomenon that incorporates ideas from social psychology, cognitive psychology, developmental psychology, and the neurosciences. Although commonly considered to be a relatively universal phenomenon with only limited importance in modern industrialized societies-more cute than critical-our research suggests precisely the opposite. In particular, we provide a measure of stable individual differences in anthropomorphism that predicts three important consequences for everyday life. This research demonstrates that individual differences in anthropomorphism predict the degree of moral care and concern afforded to an agent, the amount of responsibility and trust placed on an agent, and the extent to which an agent serves as a source of social influence on the self. These consequences have implications for disciplines outside of psychology including human-computer interaction, business (marketing and finance), and law. Concluding discussion addresses how understanding anthropomorphism not only informs the burgeoning study of nonpersons, but how it informs classic issues underlying person perception as well. © The Author(s) 2010.

  7. Mechanisms of Individual Differences in Impulsive and Risky Choice in Rats

    Science.gov (United States)

    Kirkpatrick, Kimberly; Marshall, Andrew T.; Smith, Aaron P.

    2016-01-01

    Individual differences in impulsive and risky choice are key risk factors for a variety of maladaptive behaviors such as drug abuse, gambling, and obesity. In our rat model, ordered individual differences are stable across choice parameters, months of testing, and span a broad spectrum, suggesting that rats, like humans, exhibit trait-level impulsive and risky choice behaviors. In addition, impulsive and risky choices are highly correlated, suggesting a degree of correlation between these two traits. An examination of the underlying cognitive mechanisms has suggested an important role for timing processes in impulsive choice. In addition, in an examination of genetic factors in impulsive choice, the Lewis rat strain emerged as a possible animal model for studying disordered impulsive choice, with this strain demonstrating deficient delay processing. Early rearing environment also affected impulsive behaviors, with rearing in an enriched environment promoting adaptable and more self-controlled choices. The combined results with impulsive choice suggest an important role for timing and reward sensitivity in moderating impulsive behaviors. Relative reward valuation also affects risky choice, with manipulation of objective reward value (relative to an alternative reference point) resulting in loss chasing behaviors that predicted overall risky choice behaviors. The combined results are discussed in relation to domain-specific versus domain-general subjective reward valuation processes and the potential neural substrates of impulsive and risky choice. PMID:27695580

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

    Science.gov (United States)

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

    2015-01-01

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

  9. Neural markers of individual and age differences in TVA attention capacity parameters

    DEFF Research Database (Denmark)

    Wiegand, Iris

    2013-01-01

    to investigate neural underpinnings of age-related changes in attentional capacities, the ERP markers of individual differences in processing speed and storage capacity were validated also in the older group. Furthermore, additional components were related to performance exclusively in elderly: Anterior N1...... with K-values only in the older group. Our findings specify age-related reorganization of attentional brain networks underlying decline and reserve and furthermore show that the distinctiveness of both functions is preserved (or even increased) in older age....... amplitudes were reduced for slower older (relative to younger and faster older) participants and correlated with C-values only in the older group. High-storage capacity older (relative to younger and low-storage capacity older participants) obtained a stronger right-central positivity, which correlated...

  10. Genomic expression differences between cutaneous cells from red hair color individuals and black hair color individuals based on bioinformatic analysis.

    Science.gov (United States)

    Puig-Butille, Joan Anton; Gimenez-Xavier, Pol; Visconti, Alessia; Nsengimana, Jérémie; Garcia-García, Francisco; Tell-Marti, Gemma; Escamez, Maria José; Newton-Bishop, Julia; Bataille, Veronique; Del Río, Marcela; Dopazo, Joaquín; Falchi, Mario; Puig, Susana

    2017-02-14

    The MC1R gene plays a crucial role in pigmentation synthesis. Loss-of-function MC1R variants, which impair protein function, are associated with red hair color (RHC) phenotype and increased skin cancer risk. Cultured cutaneous cells bearing loss-of-function MC1R variants show a distinct gene expression profile compared to wild-type MC1R cultured cutaneous cells. We analysed the gene signature associated with RHC co-cultured melanocytes and keratinocytes by Protein-Protein interaction (PPI) network analysis to identify genes related with non-functional MC1R variants. From two detected networks, we selected 23 nodes as hub genes based on topological parameters. Differential expression of hub genes was then evaluated in healthy skin biopsies from RHC and black hair color (BHC) individuals. We also compared gene expression in melanoma tumors from individuals with RHC versus BHC. Gene expression in normal skin from RHC cutaneous cells showed dysregulation in 8 out of 23 hub genes (CLN3, ATG10, WIPI2, SNX2, GABARAPL2, YWHA, PCNA and GBAS). Hub genes did not differ between melanoma tumors in RHC versus BHC individuals. The study suggests that healthy skin cells from RHC individuals present a constitutive genomic deregulation associated with the red hair phenotype and identify novel genes involved in melanocyte biology.

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

    Science.gov (United States)

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

    2016-01-01

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

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

    Directory of Open Access Journals (Sweden)

    Nichola eStreet

    2016-05-01

    Full Text Available Fractal patterns offer one way to represent the rough complexity of the natural world. Whilst they dominate many of our visual experiences in nature, little large-scale perceptual research has been done to explore how we respond aesthetically to these patterns. Previous research (Taylor et al., 2011 suggests that the fractal patterns with mid-range fractal dimensions have universal aesthetic appeal. Perceptual and aesthetic responses to visual complexity have been more varied with findings suggesting both linear (Forsythe et al., 2011 and curvilinear (Berlyne, 1970 relationships. Individual differences have been found to account for many of the differences we see in aesthetic responses but some, such as culture, have received little attention within the fractal and complexity research fields. This 2-study paper aims to test preference responses to fractal dimension and visual complexity, using a large cohort (N=443 of participants from around the world to allow universality claims to be tested. It explores the extent to which age, culture and gender can predict our preferences for fractally complex patterns. Following exploratory analysis that found strong correlations between fractal dimension and visual complexity, a series of linear mixed-effect models were implemented to explore if each of the individual variables could predict preference. The first tested a linear complexity model (likelihood of selecting the more complex image from the pair of images and the second a mid-range fractal dimension model (likelihood of selecting an image within mid-range. Results show that individual differences can reliably predict preferences for complexity across culture, gender and age. However, in fitting with current findings the mid-range models show greater consistency in preference not mediated by gender, age or culture. This paper supports the established theory that the mid-range fractal patterns appear to be a universal construct underlying

  13. 26 CFR 1.37-3 - Credit for individuals under age 65 who have public retirement system income.

    Science.gov (United States)

    2010-04-01

    ... received under a qualified bond purchase plan, and certain individual retirement accounts or annuities. (ii..., that is, the age at which the individual would be eligible to receive a pension or annuity without... 26 Internal Revenue 1 2010-04-01 2010-04-01 true Credit for individuals under age 65 who have...

  14. 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

  15. The Multifold Relationship Between Memory and Decision Making: An Individual-differences Study

    Science.gov (United States)

    Del Missier, Fabio; Mäntylä, Timo; Hansson, Patrik; Bruine de Bruin, Wändi; Parker, Andrew M.; Nilsson, Lars-Göran

    2014-01-01

    Several judgment and decision-making tasks are assumed to involve memory functions, but significant knowledge gaps on the memory processes underlying these tasks remain. In a study on 568 adults between 25 to 80 years, hypotheses were tested on the specific relationships between individual differences in working memory, episodic memory, and semantic memory, respectively, and six main components of decision-making competence. In line with the hypotheses, working memory was positively related with the more cognitively-demanding tasks (Resistance to Framing, Applying Decision Rules, and Under/Overconfidence), whereas episodic memory was positively associated with a more experience-based judgment task (Recognizing Social Norms). Furthermore, semantic memory was positively related with two more knowledge-based decision-making tasks (Consistency in Risk Perception and Resistance to Sunk Costs). Finally, the age-related decline observed in some of the decision-making tasks was (partially or totally) mediated by the age-related decline in working memory or episodic memory. These findings are discussed in relation to the functional roles fulfilled by different memory processes in judgment and decision-making tasks. PMID:23565790

  16. Computer Learning Environments and the Study of Individual Differences in Self-Regulation.

    Science.gov (United States)

    Mandinach, Ellen B.

    Computers provide particularly powerful environments in which to examine individual differences in cognitive processing and learning outcomes. The computer's capacity to collect and record response protocols facilitates detailed process analysis. Such analyses contribute to increased understanding of how individuals differ in their ability to…

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

    Science.gov (United States)

    Kubat, Ulas

    2018-01-01

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

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

    NARCIS (Netherlands)

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

    2013-01-01

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

  19. 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…

  20. 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

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

    NARCIS (Netherlands)

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

    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

  2. Individual Differences in Category Learning: Sometimes Less Working Memory Capacity Is Better than More

    Science.gov (United States)

    DeCaro, Mari S.; Thomas, Robin D.; Beilock, Sian L.

    2008-01-01

    We examined whether individual differences in working memory influence the facility with which individuals learn new categories. Participants learned two different types of category structures: "rule-based" and "information-integration." Successful learning of the former category structure is thought to be based on explicit…

  3. Mineralogical composition changes of postagrogenic soils under different plant communities.

    Science.gov (United States)

    Churilin, Nikita; Chizhikova, Natalia; Varlamov, Evgheni; Churilina, Alexandra

    2017-04-01

    Plant communities play the leading role in transformation of soil. The need of studying former arable lands increases due to large number of abandoned lands in Russia. It is necessary to study mineralogical composition of soils involved into natural processes to understand the trends of their development after agricultural activities in the past. The aim of the study is to identify changes in mineralogical composition of soils under the influence of different plant communities. Soils were sampled in the south of Arkhangelsk region, Ustyansky district, near Akichkin Pochinok village. Soils are formed on clay moraine of Moscow glaciation. Soil profiles were dug on interfluve. We selected 4 plant communities on different stages of succession: upland meadow with domination of sod grasses (Phleum pratense, Agrostis tenuis), 16-year-old birch forest where dominants are herbaceous plants such as Poa sp., Chamerion angustiflium, Agrostis tenuis, 16-year-old spruce forest with no herbaceous vegetation and 70-year-old bilberry spruce forest with domination of Vaccinium myrtillus and Vaccinium vitis-idaea. To separate soil fractions mineral content. We noticed a clear differentiation of studied soils both in the content of fraction and composition of minerals. Mineralogical composition and major mineral phases correlation of profiles under 70 years and 16 years of spruce forests are different. Mineralogical content in upper part of profile under the young spruce is more differentiated than in old spruce forest: the amount of quartz and kaolinite increases in upper horizon, although in this case the overall pattern of profile formation of clay material during podzolization remains unchanged. There is more substantial desilting under the birch forest, compared with profile under the spruce of same age within top 50 cm. Under the meadow vegetation we've discovered differentiation in mineral composition. Upper horizons contain smectite phase and differ from the underlying

  4. Seismic Behaviour Evaluation of Suleymaniye Mosque Under Different Earthquake Records

    OpenAIRE

    Aslan, Ayhan; Sahin, Abdurrahman

    2018-01-01

    In this study, 3D structural model of SuleymaniyeMosque which Mimar Sinan began the construction in 1550and finished in 7 years is developed and the behavior isexamined under the influence of different earthquakes. Finiteelement (FE) model of the structure is generated and modalanalysis is carried out. The obtained dynamic characteristicssuch as natural frequencies and mode shapes are comparedwith experimental works and the FE model is updated.Earthquake analysis of the mosque is carried out ...

  5. Bank stress testing under different balance sheet assumptions

    OpenAIRE

    Busch, Ramona; Drescher, Christian; Memmel, Christoph

    2017-01-01

    Using unique supervisory survey data on the impact of a hypothetical interest rate shock on German banks, we analyse price and quantity effects on banks' net interest margin components under different balance sheet assumptions. In the first year, the cross-sectional variation of banks' simulated price effect is nearly eight times as large as the one of the simulated quantity effect. After five years, however, the importance of both effects converges. Large banks adjust their balance sheets mo...

  6. Demography and the statistics of lifetime economic transfers under individual stochasticity

    NARCIS (Netherlands)

    Caswell, H.; Kluge, F.A.

    2015-01-01

    Background: As individuals progress through the life cycle, they receive income and consume goods and services. The age schedules of labor income, consumption, and life cycle deficit reflect the economic roles played at different ages. Lifetime accumulation of economic variables has been less well

  7. How can individual differences in autobiographical memory distributions of older adults be explained?

    Science.gov (United States)

    Wolf, Tabea; Zimprich, Daniel

    2016-10-01

    The reminiscence bump phenomenon has frequently been reported for the recall of autobiographical memories. The present study complements previous research by examining individual differences in the distribution of word-cued autobiographical memories. More importantly, we introduce predictor variables that might account for individual differences in the mean (location) and the standard deviation (scale) of individual memory distributions. All variables were derived from different theoretical accounts for the reminiscence bump phenomenon. We used a mixed location-scale logitnormal model, to analyse the 4602 autobiographical memories reported by 118 older participants. Results show reliable individual differences in the location and the scale. After controlling for age and gender, individual proportions of first-time experiences and individual proportions of positive memories, as well as the ratings on Openness to new Experiences and Self-Concept Clarity accounted for 29% of individual differences in location and 42% of individual differences in scale of autobiographical memory distributions. Results dovetail with a life-story account for the reminiscence bump which integrates central components of previous accounts.

  8. Neurophysiological measures of working memory and individual differences in cognitive ability and cognitive style.

    Science.gov (United States)

    Gevins, A; Smith, M E

    2000-09-01

    The capacity to deliberately control attention in order to hold and manipulate information in working memory is critical to higher cognitive functions. This suggests that between-subject differences in general cognitive ability might be related to observable differences in the activity of brain systems that support working memory and attention control. To test this notion, electroencephalograms were recorded from 80 healthy young adults during spatial working memory tasks. Measures of task-related neurophysiological and behavioral variables were derived from these data and compared to scores on a test battery commonly used to assess general cognitive ability (the WAIS-R). Subjects who scored high on the psychometric test also tended to respond faster in the experimental tasks without any loss of accuracy. The amplitude of the late positive component of the event-related potential was larger in high-ability subjects, and the frontal midline theta component of the EEG signal was also selectively enhanced in this group under conditions of sustained performance and high working memory load. These results suggest that subjects who scored high on the WAIS-R were better able to focus and sustain attention to task performance. Changes in the EEG alpha rhythm in response to manipulations of task practice and load were also examined and compared between frontal and parietal regions. The results indicated that high-ability subjects developed strategies that made relatively greater use of parietal regions, whereas low-ability subjects relied more exclusively on frontal regions. Other analyses indicated that hemispheric asymmetries in alpha band measures distinguish between individuals with relatively high verbal aptitude and those with relatively high nonverbal aptitude. In particular, subjects with a verbal cognitive style tended to make greater use of the left parietal region during task performance, and subjects with a nonverbal style tended to make greater use of the right

  9. Equivalent Electrical Circuits of Thermoelectric Generators under Different Operating Conditions

    Directory of Open Access Journals (Sweden)

    Saima Siouane

    2017-03-01

    Full Text Available Energy harvesting has become a promising and alternative solution to conventional energy generation patterns to overcome the problem of supplying autonomous electrical systems. More particularly, thermal energy harvesting technologies have drawn a major interest in both research and industry. Thermoelectric Generators (TEGs can be used in two different operating conditions, under constant temperature gradient or constant heat flow. The commonly used TEG electrical model, based on a voltage source in series with an electrical resistance, shows its limitations especially under constant heat flow conditions. Here, the analytical electrical modeling, taking into consideration the internal and contact thermal resistances of a TEG under constant temperature gradient and constant heat flow conditions, is first given. To give further insight into the electrical behavior of a TEG module in different operating conditions, we propose a new and original way of emulating the above analytical expressions with usual electronics components (voltage source, resistors, diode, whose values are determined with the TEG’s parameters. Note that such a TEG emulation is particularly suited when designing the electronic circuitry commonly associated to the TEG, to realize both Maximum Power Point Tracking and output voltage regulation. First, the proposed equivalent electrical circuits are validated through simulation with a SPICE environment in static operating conditions using only one value of either temperature gradient or heat flow. Then, they are also analyzed in dynamic operating conditions where both temperature gradient and heat flow are considered as time-varying functions.

  10. Posture-Dependent Corticomotor Excitability Differs Between the Transferred Biceps in Individuals With Tetraplegia and the Biceps of Nonimpaired Individuals.

    Science.gov (United States)

    Peterson, Carrie L; Rogers, Lynn M; Bednar, Michael S; Bryden, Anne M; Keith, Michael W; Perreault, Eric J; Murray, Wendy M

    2017-04-01

    Following biceps transfer to enable elbow extension in individuals with tetraplegia, motor re-education may be facilitated by greater corticomotor excitability. Arm posture modulates corticomotor excitability of the nonimpaired biceps. If arm posture also modulates excitability of the transferred biceps, posture may aid in motor re-education. Our objective was to determine whether multi-joint arm posture affects corticomotor excitability of the transferred biceps similar to the nonimpaired biceps. We also aimed to determine whether corticomotor excitability of the transferred biceps is related to elbow extension strength and muscle length. Corticomotor excitability was assessed in 7 arms of individuals with tetraplegia and biceps transfer using transcranial magnetic stimulation and compared to biceps excitability of nonimpaired individuals. Single-pulse transcranial magnetic stimulation was delivered to the motor cortex with the arm in functional postures at rest. Motor-evoked potential amplitude was recorded via surface electromyography. Elbow moment was recorded during maximum isometric extension trials, and muscle length was estimated using a biomechanical model. Arm posture modulated corticomotor excitability of the transferred biceps differently than the nonimpaired biceps. Elbow extension strength was positively related and muscle length was unrelated, respectively, to motor-evoked potential amplitude across the arms with biceps transfer. Corticomotor excitability of the transferred biceps is modulated by arm posture and may contribute to strength outcomes after tendon transfer. Future work should determine whether modulating corticomotor excitability via posture promotes motor re-education during the rehabilitative period following surgery.

  11. Acrylamide reduction under different pre-treatments in French fries

    DEFF Research Database (Denmark)

    Pedreschi, Franco; Kaack, Karl; Granby, Kit

    2007-01-01

    Acrylamide formation in French fries was investigated in relation under different processing conditions and the content of glucose and asparagine of the strips before frying. Potato strips (0.8 x 0.8 x 5 cm) of Bintje variety were fried at 150, 170 and 190 degrees C until reaching moisture contents...... of 10,g/L for an hour; (iii) blanched in hot water at six different time-temperature combinations (50 degrees C for 40 and 80 min; 70 degrees C for 10 and 45 min; 90 degrees C for 3 and 10 min). Acrylamide content was determined in French fries while the glucose and asparagine content in the potato...... color difference showed high correlation (r(2) of 0.854) with the acrylamide content of French fries....

  12. Cognitive mechanisms underlying Armoni: a computer-assisted cognitive training programme for individuals with intellectual disabilities

    Directory of Open Access Journals (Sweden)

    Claudia Peñaloza

    2016-01-01

    Full Text Available Although a number of cognitive deficits have been described in individuals with intellectual disabilities (ID, few studies have examined the use of computer-assisted cognitive training programmes in this group of people. This study sought to determine the cognitive mechanisms underlying 16 activities included in Armoni, a computerized cognitive training programme for individuals with ID, in order to validate its use with this population. Fifty adults with ID from four residential care centres in Spain underwent neuropsychological testing tapping attention, verbal memory, visual memory, comprehension, visuoperception, visuoconstruction, naming ability, verbal fluency, verbal reasoning and motor function. In addition, they performed 16 activities included in the Armoni programme. The relationships between cognitive function and the computer-based activities were assessed using Spearman correlations. Stepwise multiple regression analyses were then used to explore how cognitive function predicted the performance of individuals with ID on the programme activities. Most programme activities correlated with visuoconstruction, comprehension and naming ability. Naming ability, visual memory, comprehension and visuoconstruction contributed the most to the predictive models regarding performance on the Armoni activities. Our findings support the validity of Armoni for cognitive training in individuals with ID.

  13. Different circulating ghrelin responses to isoglucidic snack food in healthy individuals.

    Science.gov (United States)

    Benedini, S; Codella, R; Caumo, A; Marangoni, F; Luzi, L

    2011-02-01

    The last decade has seen much debate on ghrelin as a potential target for treating obesity. Despite a close connection between snack food intake and obesity, snacking is controversially reviewed as a good habit in a healthy nutritional regimen. The aim of the study was to evaluate whether a different nutrient composition influences postprandial ghrelin levels and glucose increments induced by 6 isoglucidic snack food. 20 healthy individuals (10 M/10 F; BMI 23.1 ± 0.5; age 33 ± 0.67 years, mean and SE) from H San Raffaele Scientific Institute and Milan University were enrolled. The subjects underwent OGTT (50 g) and 6 isoglucidic test-meal loads to assess the ghrelin circulating levels and the area under glycemic curves induced by 6 commercial snacks. 3 h after hazelnut chocolate intake, ghrelin was significantly lower than with wafer chocolate intake (psnacks, the glycemic curves were not different even though hazelnut chocolate showed the lowest glycemic curve. Moreover, snack fat content was found to be inversely correlated to 3-h plasma ghrelin levels (psnack food administered in equivalent glucidic loads elicits postprandial ghrelin suppression and satiety ratings in different ways. Further studies are needed to elucidate the role of ghrelin as hunger-hormone in the regulation of energy balance. © Georg Thieme Verlag KG Stuttgart · New York.

  14. The influence of perceptual similarity and individual differences on false memories in aging.

    Science.gov (United States)

    Dennis, Nancy A; Turney, Indira C

    2018-02-01

    Previous false memory research has suggested that older adults' false memories are based on an overreliance on gist processing in the absence of item-specific details. Yet, false memory studies have rarely taken into consideration the precise role of item-item similarity on the cognitive and neural mechanisms underlying perceptual false memories in older adults. In addition, work in our laboratory has suggested that when investigating the neural basis of false memories in older adults, it is equally as critical to take into account interindividual variability in behavior. With both factors in mind, the present study was the first to examine how both controlled, systematic differences in perceptual relatedness between targets and lures and individual differences in true and false recognition contribute to the neural basis of both true and false memories in older adults. Results suggest that between-subject variability in memory performance modulates neural activity in key regions associated with false memories in aging, whereas systematic differences in perceptual similarity did not modulate neural activity associated with false memories. Copyright © 2017 Elsevier Inc. All rights reserved.

  15. Comparative secretome analysis of rat stomach under different nutritional status

    Directory of Open Access Journals (Sweden)

    Lucia L. Senin

    2015-06-01

    Full Text Available The fact that gastric surgery is at the moment the most effective treatment to fight against obesity highlights the relevance of gastric derived proteins as potential targets to treat this pathology. Taking advantage of a previously established gastric explant model for endocrine studies, the proteomic analysis of gastric secretome was performed. To validate this gastric explant system for proteomic analysis, the identification of ghrelin, a classical gastric derived peptide, was performed by MS. In addition, the differential analysis of gastric secretomes under differential nutritional status (control feeding vs fasting vs re-feeding was performed. The MS identified proteins are showed in the present manuscript. The data supplied in this article is related to the research article entitled “Comparative secretome analysis of rat stomach under different nutritional status” [1].

  16. Reliability Analysis of a Green Roof Under Different Storm Scenarios

    Science.gov (United States)

    William, R. K.; Stillwell, A. S.

    2015-12-01

    Urban environments continue to face the challenges of localized flooding and decreased water quality brought on by the increasing amount of impervious area in the built environment. Green infrastructure provides an alternative to conventional storm sewer design by using natural processes to filter and store stormwater at its source. However, there are currently few consistent standards available in North America to ensure that installed green infrastructure is performing as expected. This analysis offers a method for characterizing green roof failure using a visual aid commonly used in earthquake engineering: fragility curves. We adapted the concept of the fragility curve based on the efficiency in runoff reduction provided by a green roof compared to a conventional roof under different storm scenarios. We then used the 2D distributed surface water-groundwater coupled model MIKE SHE to model the impact that a real green roof might have on runoff in different storm events. We then employed a multiple regression analysis to generate an algebraic demand model that was input into the Matlab-based reliability analysis model FERUM, which was then used to calculate the probability of failure. The use of reliability analysis as a part of green infrastructure design code can provide insights into green roof weaknesses and areas for improvement. It also supports the design of code that is more resilient than current standards and is easily testable for failure. Finally, the understanding of reliability of a single green roof module under different scenarios can support holistic testing of system reliability.

  17. A Review: The Probiotic Bacteria Viability under Different Conditions

    Directory of Open Access Journals (Sweden)

    Lavinia Florina CALINOIU

    2016-11-01

    Full Text Available This review summarized the current knowledge on probiotics and on the effects that different conditions have under this type of bacteria. The purpose of this review was to evaluate the survival rate/resistance or viability of different probiotic bacteria under several conditions, such as: processing, food composition, storage, freezing, thawing, refrigeration, temperature, oxygen, pH, gastrointestinal environment and package. Nowadays, the demand on probiotic functional foods is increasing rapidly, as the consumers became more aware about the potential health benefits, due to the fact that probiotics help in maintaining the balance and composition of intestinal flora and protect it from pathogens. A daily ingestion of 108–109 CFU ml−1 probiotic microorganisms is crucial in order to be able to demonstrate an effect in our organism, considering the dose and the effect of storage/gastrointestinal environments on the probiotic viability. Microencapsulation of probiotics in different polysaccharides was proven to be an ideal way to preserve and protect the cells from detrimental factors during processing, storage or resistance in the gastrointestinal transit, as many studies demonstrate it. There is a general interest in the improvement of the physical and mechanical stability of the polymers used in probiotics encapsulation, to ensure high population of probiotics not only in food during storage, but also after gastrointestinal digestion. Also, the carrier plays a very important role and should be carefully examined.

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

    DEFF Research Database (Denmark)

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

    2003-01-01

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

  19. 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.

  20. 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…

  1. 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…

  2. 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…

  3. Making workplaces safer: The influence of organisational climate and individual differences on safety behaviour

    OpenAIRE

    Michelle Ann Toppazzini; Karl Kilian Konrad Wiener

    2017-01-01

    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...

  4. Investigating Gender Differences under Time Pressure in Financial Risk Taking.

    Science.gov (United States)

    Xie, Zhixin; Page, Lionel; Hardy, Ben

    2017-01-01

    There is a significant gender imbalance on financial trading floors. This motivated us to investigate gender differences in financial risk taking under pressure. We used a well-established approach from behavior economics to analyze a series of risky monetary choices by male and female participants with and without time pressure. We also used second to fourth digit ratio (2D:4D) and face width-to-height ratio (fWHR) as correlates of pre-natal exposure to testosterone. We constructed a structural model and estimated the participants' risk attitudes and probability perceptions via maximum likelihood estimation under both expected utility (EU) and rank-dependent utility (RDU) models. In line with existing research, we found that male participants are less risk averse and that the gender gap in risk attitudes increases under moderate time pressure. We found that female participants with lower 2D:4D ratios and higher fWHR are less risk averse in RDU estimates. Males with lower 2D:4D ratios were less risk averse in EU estimations, but more risk averse using RDU estimates. We also observe that men whose ratios indicate a greater prenatal exposure to testosterone exhibit a greater optimism and overestimation of small probabilities of success.

  5. Features of electroretinogram on rat under different color stimulation

    Directory of Open Access Journals (Sweden)

    Qing-Lin Cao

    2014-04-01

    Full Text Available AIM: To research the feature of normal SD rat and retinal cone dysfunction(RCDrat electroretinogram(ERGunder different color stimulation and to explore its possible diagnostic value. METHODS: Six male SD rats and six RCD rats were used, all of which were mature rats. They were stimulated by red, white, blue and green light and the ERG was recorded. The wavelength of red, green and blue light were 625nm, 525nm and 470nm respectively and the white light was mixed by three color light.RESULTS: The response of ERG in normal SD rat under green and blue light stimulation were stronger than under red and white stimulation. The dark-adapted ERG of RCD rat responsed to color stimulation was similar to the ERG of normal SD rat, but the amplitude under each color stimulation was lower than that of normal SD rat. Light-adapted ERG response was hardly detected waveform.CONCLUSION: Rat is sensitive to blue and green light, which can be used as a suggested light stimulation in the ERG recording. The ERG of RCD rat is not specific for color stimulation, and at present we could not use color ERG as a diagnostic indicator.

  6. Changes on P availability under different soil management

    International Nuclear Information System (INIS)

    Parada, A.M; Pino, I; Rouanet, J.L; Nario, A; Videla, X; Albornoz, M.P

    2003-01-01

    The volcanic ash soils in the IX Region has a high P retention capacity and due to the high cost of fertilizers in the agricultural production, it's necessary to realize researches in order to study the availability of nutrients in soils to optimize their efficiency. A trial was carried out under two management systems: no tillage without burning crop residues (NT-B) and no tillage burning crop residues (NT+B), during three years with two crop rotation; Lupine-wheat-oat (S1)and Wheat-lupine-wheat (S2). The objective of this experiment was to evaluate and predict the influence of the management system used over the bioavailable P through time. It was used conventional and isotopic techniques (Fardeau, 1997). At the beginning of the experiment, the exchangeable isotopic values showed a low bioavailable P in the soil under both tillage management system. At the end of the experiment, the soil presented a positive behavior under the NT-B system, shoving a high value for the bioavailable P, whilst the P retention capacity tend to decrease. With this system it was observed a P redistribution in different pools, with a better available P for the crops through the time, which doesn't observed in the other system wit burning residues (author)

  7. Investigating Gender Differences under Time Pressure in Financial Risk Taking

    Directory of Open Access Journals (Sweden)

    Zhixin Xie

    2017-12-01

    Full Text Available There is a significant gender imbalance on financial trading floors. This motivated us to investigate gender differences in financial risk taking under pressure. We used a well-established approach from behavior economics to analyze a series of risky monetary choices by male and female participants with and without time pressure. We also used second to fourth digit ratio (2D:4D and face width-to-height ratio (fWHR as correlates of pre-natal exposure to testosterone. We constructed a structural model and estimated the participants' risk attitudes and probability perceptions via maximum likelihood estimation under both expected utility (EU and rank-dependent utility (RDU models. In line with existing research, we found that male participants are less risk averse and that the gender gap in risk attitudes increases under moderate time pressure. We found that female participants with lower 2D:4D ratios and higher fWHR are less risk averse in RDU estimates. Males with lower 2D:4D ratios were less risk averse in EU estimations, but more risk averse using RDU estimates. We also observe that men whose ratios indicate a greater prenatal exposure to testosterone exhibit a greater optimism and overestimation of small probabilities of success.

  8. Biologically Driven Differences in Decomposition Dynamics Under Changing Ecosystems (Invited)

    Science.gov (United States)

    Grandy, S.

    2010-12-01

    Predicting the effects of environmental changes on soil organic matter dynamics remains difficult. Here I explore the possibility that differences in decomposition and soil organic matter dynamics are due in part to links between litter decomposition processes, changes in litter chemistry, and variation in decomposer communities. I explored these relationships under three types of ecosystem changes: 1) N enrichment of forest ecosystems; 2) elevated atmospheric carbon dioxide concentrations in forest ecosystems; and 3) agricultural land-use intensification. My overarching hypothesis was that litter mass loss and litter chemistry would vary under different environmental conditions, and those differences would correlate with ecosystem-specific variations in decomposer community structure and function. In three separate field experiments, I found strong evidence that decomposer communities influenced the chemistry of decomposing litter. In a related laboratory study I found that the presence of the oribatid mite Scheloribates moestus Banks (Acari: Oribatida) can substantially change litter decomposition dynamics and the molecular chemistry of decomposing litter. Most current conceptual models estimate changes in litter chemistry over the course of decomposition from initial litter chemistry and the extent of mass loss. These models suggest consistent and predictable changes in the chemical structure of organic matter during decomposition and do not explicitly consider the potential effects of variations in decomposer community structure on decomposition. In contrast, my results show that differences in decomposer communities lead to changes in litter chemistry during decomposition. Accurately predicting management effects on litter chemistry. and thus also soil organic matter dynamics, through time may require accounting for the degree to which variations in decomposer community composition influence organic matter chemistry.

  9. Individual differences in circadian locomotor parameters correlate with anxiety- and depression-like behavior.

    Directory of Open Access Journals (Sweden)

    Jeffrey Anyan

    Full Text Available Disrupted circadian rhythms are a core feature of mood and anxiety disorders. Circadian rhythms are coordinated by a light-entrainable master clock located in the suprachiasmatic nucleus. Animal models of mood and anxiety disorders often exhibit blunted rhythms in locomotor activity and clock gene expression. Interestingly, the changes in circadian rhythms correlate with mood-related behaviours. Although animal models of depression and anxiety exhibit aberrant circadian rhythms in physiology and behavior, it is possible that the methodology being used to induce the behavioral phenotype (e.g., brain lesions, chronic stress, global gene deletion affect behavior independently of circadian system. This study investigates the relationship between individual differences in circadian locomotor parameters and mood-related behaviors in healthy rats. The circadian phenotype of male Lewis rats was characterized by analyzing wheel running behavior under standard 12h:12h LD conditions, constant dark, constant light, and rate of re-entrainment to a phase advance. Rats were then tested on a battery of behavioral tests: activity box, restricted feeding, elevated plus maze, forced swim test, and fear conditioning. Under 12h:12h LD conditions, percent of daily activity in the light phase and variability in activity onset were associated with longer latency to immobility in the forced swim test. Variability in onset also correlated positively with anxiety-like behavior in the elevated plus maze. Rate of re-entrainment correlated positively with measures of anxiety in the activity box and elevated plus maze. Lastly, we found that free running period under constant dark was associated with anxiety-like behaviors in the activity box and elevated plus maze. Our results provide a previously uncharacterized relationship between circadian locomotor parameters and mood-related behaviors in healthy rats and provide a basis for future examination into circadian clock

  10. Demography and the statistics of lifetime economic transfers under individual stochasticity

    Directory of Open Access Journals (Sweden)

    Hal Caswell

    2015-02-01

    Full Text Available Background: As individuals progress through the life cycle, they receive income and consume goods and services. The age schedules of labor income, consumption, and life cycle deficit reflect the economic roles played at different ages. Lifetime accumulation of economic variables has been less well studied, and our goal here is to rectify that. Objective: To derive and apply a method to compute the lifetime accumulated labor income, consumption, and life cycle deficit, and to go beyond the calculation of mean lifetime accumulation to calculate statistics of variability among individuals in lifetime accumulation. Methods: To quantify variation among individuals, we calculate the mean, standard deviation, coefficient of variation, and skewness of lifetime accumulated transfers, using the theory of Markov chains with rewards (Caswell 2011, applied to National Transfer Account data for Germany of 1978, and 2003. Results: The age patterns of lifetime accumulated labor income are relatively stable over time. Both the mean and the standard deviation of remaining lifetime labor income decline with age; the coefficient of variation, measuring variation relative to the mean, increases dramatically with age. The skewness becomes large and positive at older ages. Education level affects all the statistics. About 30Š of the variance in lifetime income is due to variance in age-specific income, and about 70Š is contributed by the mortality schedule. Lifetime consumption is less variable (as measured by the CV than lifetime labor income. Conclusions: We conclude that demographic Markov chains with rewards can add a potentially valuable perspective to studies of the economic lifecycle. The variation among individuals in lifetime accumulations in our results reflects individual stochasticity, not heterogeneity among individuals. Incorporating heterogeneity remains an important problem.

  11. Discontinuous growth modeling of adaptation to sleep setting changes: individual differences and age.

    Science.gov (United States)

    Bliese, Paul D; McGurk, Dennis; Thomas, Jeffrey L; Balkin, Thomas J; Wesensten, Nancy

    2007-05-01

    Biomedical devices allow investigators to collect long-term repeated measures data to study adaptation. We examined 26 d of actigraph sleep data and tested for individual differences in sleep patterns prior to, during, and after a transition of sleeping in garrison to sleeping in a field exercise setting. In addition, we examined whether the individual difference variable of participant age (a continuous variable ranging from 19-29 yr) was related to sleep patterns. Actigraph data was obtained from 77 cadets participating in a month-long military training program. At day 17, participants transitioned from sleeping in garrison to sleeping in a field exercise setting. A discontinuous growth model tested for individual differences in 1) overall sleep time, 2) garrison sleep slope, 3) the transition, and 4) the sleep slope during the field exercise setting. Individuals varied significantly in their overall sleep time, pattern of sleep in garrison, and the degree to which sleep decreased at the transition. The decline in sleep at the transition was related to participant age such that increases in age were associated with larger declines in sleep minutes. Individuals display significant variability in sleep patterns that can be detected using discontinuous growth models. The individual difference variable of participant age explains some of this variability. Much of the variability, however, remains unexplained. Future work will benefit from using discontinuous growth models to identify and model individual difference variables such as age when examining response patterns and transitions in data collected in applied field settings.

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

    Directory of Open Access Journals (Sweden)

    Nathalie Mella

    2018-02-01

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

  13. 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.

  14. Individual Differences in Verbal and Spatial Stroop Tasks: Interactive Role of Handedness and Domain

    Science.gov (United States)

    Capizzi, Mariagrazia; Ambrosini, Ettore; Vallesi, Antonino

    2017-01-01

    A longstanding debate in psychology concerns the relation between handedness and cognitive functioning. The present study aimed to contribute to this debate by comparing performance of right- and non-right-handers on verbal and spatial Stroop tasks. Previous studies have shown that non-right-handers have better inter-hemispheric interaction and greater access to right hemisphere processes. On this ground, we expected performance of right- and non-right-handers to differ on verbal and spatial Stroop tasks. Specifically, relative to right-handers, non-right-handers should have greater Stroop effect in the color-word Stroop task, for which inter-hemispheric interaction does not seem to be advantageous to performance. By contrast, non-right-handers should be better able to overcome interference in the spatial Stroop task. This is for their preferential access to the right hemisphere dealing with spatial material and their greater inter-hemispheric interaction with the left hemisphere hosting Stroop task processes. Our results confirmed these predictions, showing that handedness and the underlying brain asymmetries may be a useful variable to partly explain individual differences in executive functions. PMID:29176946

  15. Individual Differences in Verbal and Spatial Stroop Tasks: Interactive Role of Handedness and Domain.

    Science.gov (United States)

    Capizzi, Mariagrazia; Ambrosini, Ettore; Vallesi, Antonino

    2017-01-01

    A longstanding debate in psychology concerns the relation between handedness and cognitive functioning. The present study aimed to contribute to this debate by comparing performance of right- and non-right-handers on verbal and spatial Stroop tasks. Previous studies have shown that non-right-handers have better inter-hemispheric interaction and greater access to right hemisphere processes. On this ground, we expected performance of right- and non-right-handers to differ on verbal and spatial Stroop tasks. Specifically, relative to right-handers, non-right-handers should have greater Stroop effect in the color-word Stroop task, for which inter-hemispheric interaction does not seem to be advantageous to performance. By contrast, non-right-handers should be better able to overcome interference in the spatial Stroop task. This is for their preferential access to the right hemisphere dealing with spatial material and their greater inter-hemispheric interaction with the left hemisphere hosting Stroop task processes. Our results confirmed these predictions, showing that handedness and the underlying brain asymmetries may be a useful variable to partly explain individual differences in executive functions.

  16. 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.

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

    NARCIS (Netherlands)

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

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

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

    NARCIS (Netherlands)

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

    2017-01-01

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

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

    NARCIS (Netherlands)

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

    2013-01-01

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

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

    OpenAIRE

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

    2016-01-01

    In this paper, we investigate whether individual differences in performance on heuristic and biases tasks can be explained by cognitive abilities, monitoring confidence, and control thresholds. Current theories explain individual differences in these tasks by the ability to detect errors and override automatic but biased judgments, and deliberative cognitive abilities that help to construct the correct response. Here we retain cognitive abilities but disentangle error detection, proposing tha...

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

    OpenAIRE

    Simon Anthony Jackson; Sabina Kleitman; Pauline Howie; Lazar Stankov

    2016-01-01

    In this paper, we investigate whether individual differences in performance on heuristic and biases tasks can be explained by cognitive abilities, monitoring confidence and control thresholds. Current theories explain individual differences in these tasks by the ability to detect errors and override automatic but biased judgements, and deliberative cognitive abilities that help to construct the correct response. Here we retain cognitive abilities but disentangle error detection, proposing tha...

  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. 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

  4. 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.

  5. DISPLACE: a dynamic, individual-based model for spatial fishing planning and effort displacement: Integrating underlying fish population models

    DEFF Research Database (Denmark)

    Bastardie, Francois; Nielsen, J. Rasmus; Miethe, Tanja

    or to the alteration of individual fishing patterns. We demonstrate that integrating the spatial activity of vessels and local fish stock abundance dynamics allow for interactions and more realistic predictions of fishermen behaviour, revenues and stock abundance......We previously developed a spatially explicit, individual-based model (IBM) evaluating the bio-economic efficiency of fishing vessel movements between regions according to the catching and targeting of different species based on the most recent high resolution spatial fishery data. The main purpose...... was to test the effects of alternative fishing effort allocation scenarios related to fuel consumption, energy efficiency (value per litre of fuel), sustainable fish stock harvesting, and profitability of the fisheries. The assumption here was constant underlying resource availability. Now, an advanced...

  6. THE EVALUATION OF SOURCES OF KNOWLEDGE UNDERLYING DIFFERENT CONCEPTUAL CATEGORIES

    Directory of Open Access Journals (Sweden)

    Guido eGainotti

    2013-02-01

    Full Text Available According to the embodied cognition theory and to the sensory-motor model of semantic knowledge: (a concepts are represented in the brain in the same format in which they have been constructed by the sensory-motor system and (b various conceptual categories differ for the weight that different kinds of information play in their representation. In our study, we have tried to check the second assumption by asking normal elderly subjects to rate their subjective evaluation of the role that various perceptual, motor and language-mediated sources of knowledge could have in the construction of different semantic categories. Our first aim consisted in rating the influence that different sources of knowledge could have in the representation of animals, plant life and artifact categories, rather than in those of living and non-living beings, as many previous studies on this subject have made. We also tried to check the influence of age and stimulus modality on these evaluations of the ‘sources of knowledge’ underlying different conceptual categories. The influence of age was checked by comparing results obtained on our group of elderly subjects with those obtained in a previous study, conducted with the same methodology on a sample of young students, whereas the influence of stimulus modality was assessed by presenting the stimuli in the verbal modality to 50 subjects and in the pictorial modality to 50 other subjects.The distinction between ‘animals’ and ‘plant life’ within the ‘living’ categories was confirmed bythe analysis of their prevalent sources of knowledge and by a cluster analysis, which allowed to distinguish fruits and vegetables from animals. Furthermore, results of the study showed: (a that the visual modality was considered by our subjects as the main source of knowledge for all the categories taken into account; (b that in biological categories the next more important source of information was represented by other

  7. Performance of NiTi endodontic instrument under different temperatures.

    Science.gov (United States)

    Jamleh, Ahmed; Yahata, Yoshio; Ebihara, Arata; Atmeh, Amre R; Bakhsh, Turki; Suda, Hideaki

    2016-09-01

    The purpose of this study was to test nickel titanium (NiTi) instrument performance under different surrounding temperatures. Twenty-four superelastic NiTi instruments with a conical shape comprising a 0.30-mm-diameter tip and 0.06 taper were equally divided into 3 groups according to the temperature employed. Using a specially designed cyclic fatigue testing apparatus, each instrument was deflected to give a curvature 10 mm in radius and a 30° angle. This position was kept as the instrument was immersed in a continuous flow of water under a temperature of 10, 37, or 50 °C for 20 s to calculate the deflecting load (DL). In the same position, the instrument was then allowed to rotate at 300 rpm to fracture, and the working time was converted to the number of cycles to fracture (NCF). The statistical significance was set at p = 0.05. The mean DL (in N) and NCF (in cycles) of the groups at 10, 37, and 50 °C were 10.16 ± 1.36 and 135.50 ± 31.48, 13.50 ± 0.92 and 89.20 ± 16.44, and 14.70 ± 1.21 and 65.50 ± 15.90, respectively. The group at 10 °C had significantly the lowest DL that favorably resulted in the highest NCF. Within the limitations of this study, the surrounding temperature influences the cyclic fatigue resistance and DL of the superelastic NiTi instruments. Lower temperatures are found to favorably decrease the DL and extend the lifetime of the superelastic NiTi instrument. Further NiTi instrument failure studies should be performed under simulated body temperature.

  8. 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.

  9. Experiments on individual strategy updating in iterated snowdrift game under random rematching.

    Science.gov (United States)

    Qi, Hang; Ma, Shoufeng; Jia, Ning; Wang, Guangchao

    2015-03-07

    How do people actually play the iterated snowdrift games, particularly under random rematching protocol is far from well explored. Two sets of laboratory experiments on snowdrift game were conducted to investigate human strategy updating rules. Four groups of subjects were modeled by experience-weighted attraction learning theory at individual-level. Three out of the four groups (75%) passed model validation. Substantial heterogeneity is observed among the players who update their strategies in four typical types, whereas rare people behave like belief-based learners even under fixed pairing. Most subjects (63.9%) adopt the reinforcement learning (or alike) rules; but, interestingly, the performance of averaged reinforcement learners suffered. It is observed that two factors seem to benefit players in competition, i.e., the sensitivity to their recent experiences and the overall consideration of forgone payoffs. Moreover, subjects with changing opponents tend to learn faster based on their own recent experience, and display more diverse strategy updating rules than they do with fixed opponent. These findings suggest that most of subjects do apply reinforcement learning alike updating rules even under random rematching, although these rules may not improve their performance. The findings help evolutionary biology researchers to understand sophisticated human behavioral strategies in social dilemmas. Copyright © 2015 Elsevier Ltd. All rights reserved.

  10. Cigar burning under different smoking intensities and effects on emissions.

    Science.gov (United States)

    Dethloff, Ole; Mueller, Christian; Cahours, Xavier; Colard, Stéphane

    2017-12-01

    The effect of smoking intensity on cigar smoke emissions was assessed under a range of puff frequencies and puff volumes. In order to potentially reduce emissions variability and to identify patterns as accurately as possible, cigar weights and diameters were measured, and outliers were excluded prior to smoking. Portions corresponding to 25%, 50%, 75% and 100% of the cigar, measured down to the butt length, were smoked under several smoking conditions, to assess nicotine, CO and water yields. The remaining cigar butts were analysed for total alkaloids, nicotine, and moisture. Results showed accumulation effects during the burning process having a significant impact on smoke emission levels. Condensation and evaporation occur and lead to smoke emissions dependent on smoking intensity. Differences were observed for CO on one side as a gas phase compound and nicotine on the other side as a particulate phase compound. For a given intensity, while CO emission increases linearly as the cigar burns, nicotine and water emissions exhibited an exponential increase. Our investigations showed that a complex phenomena occurs during the course of cigar smoking which makes emission data: difficult to interpret, is potentially misleading to the consumer, and inappropriate for exposure assessment. The results indicate that, tobacco content and physical parameters may well be the most robust basis for product characterisation and comparison rather than smoke emission. Copyright © 2017 Elsevier Inc. All rights reserved.

  11. Overhead Transmission Lines Deicing under Different Incentive Displacement

    Directory of Open Access Journals (Sweden)

    Qing He

    2014-01-01

    Full Text Available Overhead transmission line icing is one of the main factors affecting safety and reliability of power grid. This paper proposed an excitation deicing method of iced wire and theoretically revealed the ice removal mechanism under displacement excitation conditions, by taking the LGJ-70/10 glaze icing wire as the 3D model and analyzing and studying its dynamic response under the effect of displacement excitation. The simulation results show that the stress of wire icing area is enlarged with the increase of excitation displacement and frequency. Through the comparison of the compression strength experimental results on a series of different iced wires in low temperature environment, the authors found out that the stress generated from the wire icing area is greater than the crushing strength of the ice within the scope of the calculation parameters, which proved the validity and the feasibility of the method, and finally the suitable excitation displacement is determined. Following studies show that, as far as possible, it is necessary to reduce the incentive displacement and also to select the appropriate constraint length in order to avoid the line jumping that may be caused by large span ice shedding.

  12. Individual Differences in Cognitive Control Circuit Anatomy Link Sensation Seeking, Impulsivity, and Substance Use

    Science.gov (United States)

    Hollinshead, Marisa O.; Roffman, Joshua L.; Smoller, Jordan W.; Buckner, Randy L.

    2016-01-01

    Individuals vary widely in their tendency to seek stimulation and act impulsively, early developing traits with genetic origins. Failures to regulate these behaviors increase risk for maladaptive outcomes including substance abuse. Here, we explored the neuroanatomical correlates of sensation seeking and impulsivity in healthy young adults. Our analyses revealed links between sensation seeking and reduced cortical thickness that were preferentially localized to regions implicated in cognitive control, including anterior cingulate and middle frontal gyrus (n = 1015). These associations generalized to self-reported motor impulsivity, replicated in an independent group (n = 219), and correlated with heightened alcohol, tobacco, and caffeine use. Critically, the relations between sensation seeking and brain structure were evident in participants without a history of alcohol or tobacco use, suggesting that observed associations with anatomy are not solely a consequence of substance use. These results demonstrate that individual differences in the tendency to seek stimulation, act on impulse, and engage in substance use are correlated with the anatomical structure of cognitive control circuitry. Our findings suggest that, in healthy populations, covariation across these complex multidimensional behaviors may in part originate from a common underlying biology. SIGNIFICANCE STATEMENT Impaired cognitive control may result in a tendency to seek stimulation impulsively and an increased risk for maladaptive outcomes, including substance abuse. Here, we examined the structural correlates of sensation seeking and impulsivity in a large cohort of healthy young adults. Our analyses revealed links between sensation seeking and reduced cortical thickness that were preferentially localized to regions implicated in cognitive control, including anterior cingulate and middle frontal gyrus. The observed associations generalized to motor impulsivity, replicated in an independent group

  13. Rule and similarity in grammar: their interplay and individual differences in the brain.

    Science.gov (United States)

    Hauser, Maximilian F A; Hofmann, Juliane; Opitz, Bertram

    2012-05-01

    Previous research on artificial grammar has indicated that the human ability to classify sentences or letter strings according to grammaticality relies on two types of knowledge. One is a superficial, familiarity-based understanding of a grammar the other is the knowledge of rules and critical features underlying a grammar. The fundamentally different characteristics of these systems permit an analysis of receiver-operating characteristics (ROC), which measures the extent to which each type of knowledge is used in grammaticality judgments. Furthermore, violations of a grammar can be divided into hierarchical and local violations. The present study is the first to combine the use of ROC analyses, fMRI and a grammaticality dichotomy. Based on previous neuroimaging studies, it was hypothesized that judgments based on rule knowledge, as extracted from individual ROC analyses, involve the left inferior frontal gyrus (IFG), whereas similarity would involve right IFG, as well as left hippocampal regions. With regards to violation types, it was hypothesized that hierarchical violations would recruit the opercular part of the left IFG as well as the posterior operculum, whereas local violations would bilaterally activate the premotor cortex (PMC). Results indicated that for greater reliance on rule knowledge, a ventral part of the left PMC was activated for ungrammatical items, whereas other PMC areas show a differentiated response for grammaticality for individuals less reliant on similarity. The right IFG was related to ungrammatical items as a function of similarity. Results are discussed with regards to possible error detection systems and differentiated efficiencies for respective classification strategies. Copyright © 2012 Elsevier Inc. All rights reserved.

  14. Turbulent boundary layer under the control of different schemes

    Science.gov (United States)

    Qiao, Z. X.; Zhou, Y.; Wu, Z.

    2017-06-01

    This work explores experimentally the control of a turbulent boundary layer over a flat plate based on wall perturbation generated by piezo-ceramic actuators. Different schemes are investigated, including the feed-forward, the feedback, and the combined feed-forward and feedback strategies, with a view to suppressing the near-wall high-speed events and hence reducing skin friction drag. While the strategies may achieve a local maximum drag reduction slightly less than their counterpart of the open-loop control, the corresponding duty cycles are substantially reduced when compared with that of the open-loop control. The results suggest a good potential to cut down the input energy under these control strategies. The fluctuating velocity, spectra, Taylor microscale and mean energy dissipation are measured across the boundary layer with and without control and, based on the measurements, the flow mechanism behind the control is proposed.

  15. Individual differences in working memory capacity and resistance to belief bias in syllogistic reasoning.

    Science.gov (United States)

    Robison, Matthew K; Unsworth, Nash

    2017-08-01

    In two experiments, we investigated the possibility that individual differences in working memory capacity (WMC) would provide resistance to belief bias in syllogistic reasoning. In Experiment 1 (N = 157), participants showed a belief bias effect in that they had longer response times and decreased accuracy on syllogisms with conflict between the validity and believability of the conclusion than on syllogisms with no such conflict. However, this effect did not differ as a function of individual differences in WMC. Experiment 2 (N = 122) replicated this effect with the addition of decontextualized (i.e., nonsense) syllogisms as a different means of measuring the magnitude of the belief bias effect. Although individual differences in WMC and fluid intelligence were related to better reasoning overall, the magnitude of the belief bias effect was not smaller for participants with greater WMC. The present study offers two novel findings: (a) The belief bias effect is independent of individual differences in WMC and fluid intelligence, and (b) resolving conflict in verbal reasoning is not a type of conflict resolution that correlates with individual differences in WMC, further establishing boundary conditions for the role of WMC in human cognitive processes.

  16. Retention Study of Flavonoids Under Different Chromatographic Modes.

    Science.gov (United States)

    Sentkowska, Aleksandra; Biesaga, Magdalena; Pyrzynska, Krystyna

    2016-04-01

    The goal of this study was to investigate the chromatographic behavior of selected flavonoids from their different subgroups (flavonols, flavanones, flavones and isoflavones) in hydrophilic interaction liquid chromatography (HILIC). Chromatographic measurements were made on two different HILIC columns: cross-linked DIOL (Luna HILIC) and zwitterionic sulfoalkylbetaine (SeQuant ZIC-HILIC). Separation parameters such as the content of acetonitrile and pH of an eluent were studied. On the ZIC column, the retention factors of flavonoids increased with decreasing water content in the mobile phase. The increase in pH of the aqueous component mainly affects the polarity of the analytes. DIOL stationary phase shows more or less apparent dual retention mechanism, HILIC at the acetonitrile (ACN) content ≥75% and reversed phase (RP) with lower content of organic modifier. In the presence of ammonium acetate in the mobile phase, the retention of flavonoids onto the DIOL column increases without change in the selectivity of the separations. The similar effect, but considerably smaller was observed for aglycones on the ZIC column. The retention of studied glycosides (hesperidin, rutin) decreases in the presence of salt in the mobile phase. The significantly higher mass spectrometry sensitivity was observed under HILIC conditions in comparison with the most often used RP LC due to much higher content of ACN in the mobile phase. Finally, under optimal chromatographic conditions, the method was validated and applied for the determination of flavonoids in chamomile (Matricaria chamomilla L.) infusion. © The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  17. Influence of Potassium on Sapric Peat under Different Environmental Conditions

    Science.gov (United States)

    Tajuddin, Syafik Akmal Mohd; Rahman, Junita Abdul; Rahim, Nor Haakmal Abd; Saphira Radin Mohamed, Radin Maya; Saeed Abduh Algheethi, Adel Ali, Dr

    2018-04-01

    Potassium is mainly present in soil in the natural form known as the K-bearing mineral. Potassium is also available in fertilizer as a supplement to plants and can be categorized as macronutrient. The application of potassium improves the texture and structure of the soil beside to improves plant growth. The main objective of this study was to determine the concentration of potassium in sapric peat under different conditions. Physical model was used as a mechanism for the analysis of the experimental data using a soil column as an equipment to produce water leaching. In this investigation, there were four outlets in the soil column which were prepared from the top of the column to the bottom with the purpose of identifying the concentration of potassium for each soil level. The water leaching of each outlet was tested using atomic absorption spectroscopy (AAS). The results obtained showed that the highest concentrations of potassium for flush condition at outlet 4 was 13.58 ppm. Similarly, sapric under rainwater condition recorded the highest value of 13.32 and 12.34 ppm respectively at outlet 4 for wet and dry condition. However, the difference in Sapric, rainwater and fertilizer category showed that the highest value for the wet condition was achieved at outlet 2 with 13.99 ppm while highest value of 14.82 ppm was obtained for the dry condition at the outlet 3. It was concluded that the outlets in the soil column gave a detailed analysis of the concentration of potassium in the soil which was influenced by the environmental conditions.

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

    Science.gov (United States)

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

    2015-09-01

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

  19. 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

  20. Differences in functional traits between invasive and native Amaranthus species under different forms of N deposition.

    Science.gov (United States)

    Wang, Congyan; Zhou, Jiawei; Liu, Jun; Jiang, Kun

    2017-08-01

    Differences in functional traits between invasive and native plant species are believed to determine the invasion success of the former. Increasing amounts of anthropogenic nitrogen (N) are continually deposited into natural ecosystems, which may change the relative occurrence of the different N deposition forms (such as NH 4 -N, NO 3 -N, and CO(NH 2 ) 2 -N) naturally deposited. Under high N deposition scenarios, some invasive species may grow faster, gaining advantage over native species. In a greenhouse experiment, we grew invasive and native Amaranthus species from seed both alone and in competition under simulated N enriched environments with different forms of N over 3 months. Then, we measured different leaf traits (i.e., plant height, leaf length, leaf width, leaf shape index, specific leaf area (SLA), and leaf chlorophyll and N concentrations). Results showed that the competition intensity between A. retroflexus and A. tricolor decreased under N deposition. This may be due to the large functional divergence between A. retroflexus and A. tricolor under simulated N deposition. Phenotypic plasticity of SLA and leaf chlorophyll concentration of A. retroflexus were significantly lower than in A. tricolor. The lower range of phenotypic plasticity of SLA and leaf chlorophyll concentration of A. retroflexus may indicate a fitness cost for plastic functional traits under adverse environments. The restricted phenotypic plasticity of SLA and leaf chlorophyll concentration of A. retroflexus may also stabilize leaf construction costs and the growth rate. Meanwhile, the two Amaranthus species possessed greater plasticity in leaf N concentration under NO 3 -N fertilization, which enhanced their competitiveness.

  1. Differences in functional traits between invasive and native Amaranthus species under different forms of N deposition

    Science.gov (United States)

    Wang, Congyan; Zhou, Jiawei; Liu, Jun; Jiang, Kun

    2017-08-01

    Differences in functional traits between invasive and native plant species are believed to determine the invasion success of the former. Increasing amounts of anthropogenic nitrogen (N) are continually deposited into natural ecosystems, which may change the relative occurrence of the different N deposition forms (such as NH4-N, NO3-N, and CO(NH2)2-N) naturally deposited. Under high N deposition scenarios, some invasive species may grow faster, gaining advantage over native species. In a greenhouse experiment, we grew invasive and native Amaranthus species from seed both alone and in competition under simulated N enriched environments with different forms of N over 3 months. Then, we measured different leaf traits (i.e., plant height, leaf length, leaf width, leaf shape index, specific leaf area (SLA), and leaf chlorophyll and N concentrations). Results showed that the competition intensity between A. retroflexus and A. tricolor decreased under N deposition. This may be due to the large functional divergence between A. retroflexus and A. tricolor under simulated N deposition. Phenotypic plasticity of SLA and leaf chlorophyll concentration of A. retroflexus were significantly lower than in A. tricolor. The lower range of phenotypic plasticity of SLA and leaf chlorophyll concentration of A. retroflexus may indicate a fitness cost for plastic functional traits under adverse environments. The restricted phenotypic plasticity of SLA and leaf chlorophyll concentration of A. retroflexus may also stabilize leaf construction costs and the growth rate. Meanwhile, the two Amaranthus species possessed greater plasticity in leaf N concentration under NO3-N fertilization, which enhanced their competitiveness.

  2. Snacking now or later? Individual differences in following intentions or habits explained by time perspective.

    Science.gov (United States)

    Onwezen, M C; Van 't Riet, J; Dagevos, H; Sijtsema, S J; Snoek, H M

    2016-12-01

    Even when individuals are aware of long-term health effects of their diet, and form healthy intentions, they often engage in relatively unhealthy snacking habits. Some individuals fall back on unhealthy habits more easily than others. We aim to explore whether time perspective can explain why some individuals are more prone to rely on habits and others on intentions. Study 1 (N = 1503) provides a first exploration of the role of time perspective by exploring individual differences in perception of long-term and short-term consequences. In accordance with our hypotheses, Study 1 shows that habits are associated with short-term consequences and intentions with long-term consequences. Study 2 (N = 1497) shows that the effects of habits on snacking behaviour are strengthened by a present time perspective, whereas the effects of intentions on snacking behaviour are strengthened by a future time perspective. These findings imply that there is a fundamental difference in the guiding function of intentions and habits which might explain individual differences in following intentions versus habits. Individuals with a long-term perspective are more inclined to follow intentions and individuals with a short-term perspective are more inclined to follow habits. Copyright © 2016 Elsevier Ltd. All rights reserved.

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

    Science.gov (United States)

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

    2016-01-01

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

  4. Optimal Tuned Mass Damper for Nonlinear Structure under Different Earthquakes

    Directory of Open Access Journals (Sweden)

    K. Shakeri

    2015-07-01

    Full Text Available Since there is no closed-form formula for designing TMD (Tuned Mass Damper for nonlinear structures, some researchers have proposed numerical optimization procedures such as a genetic algorithm to obtain the optimal values of TMD parameters for nonlinear structures. These methods are based on determining the optimal values of TMD parameters to minimize the maximum response (e.g. inter story drift of the controlled structure subjected to a specific earthquake record. Therefore, the performance of TMD that has been designed using a specific record strongly depends on the characteristics of the earthquake record. By changing the characteristics of the input earthquake record, the efficiency of TMD is changed and in some cases, it is possible that the response of the controlled structure is increased. To overcome the shortcomings of the previous researches, in this paper, an efficient method for designing optimal TMD on nonlinear structures is proposed, in which the effect of different ground motion records is considered in the design procedure. In the proposed method, the optimal value of the TMD parameters are determined so that the average maximum response (e.g. inter story drift resulting from different records in the controlled structure is minimized. To illustrate the procedure of the propose method, the method is used to design optimal TMD for a sample structure. The results of numerical simulations show that the average maximum response of controlled structure resulting from different records is reduced significantly. Hence, it can be concluded that the proposed method for designing optimal TMD under different earthquakes is effective.

  5. Patient-specific modeling and analysis of dynamic behavior of individual sickle red blood cells under hypoxic conditions

    Science.gov (United States)

    Li, Xuejin; Du, E.; Li, Zhen; Tang, Yu-Hang; Lu, Lu; Dao, Ming; Karniadakis, George

    2015-11-01

    Sickle cell anemia is an inherited blood disorder exhibiting heterogeneous morphology and abnormal dynamics under hypoxic conditions. We developed a time-dependent cell model that is able to simulate the dynamic processes of repeated sickling and unsickling of red blood cells (RBCs) under physiological conditions. By using the kinetic cell model with parameters derived from patient-specific data, we present a mesoscopic computational study of the dynamic behavior of individual sickle RBCs flowing in a microfluidic channel with multiple microgates. We investigate how individual sickle RBCs behave differently from healthy ones in channel flow, and analyze the alteration of cellular behavior and response to single-cell capillary obstruction induced by cell rheologic rigidification and morphological change due to cell sickling under hypoxic conditions. We also simulate the flow dynamics of sickle RBCs treated with hydroxyurea (HU) and quantify the relative enhancement of hemodynamic performance of HU. This work was supported by the National Institutes of Health (NIH) Grant U01HL114476.

  6. 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.

  7. Can individual health differences be explained by workplace characteristics?--A multilevel analysis.

    Science.gov (United States)

    Marklund, Staffan; Bolin, Malin; von Essen, Jan

    2008-02-01

    Research on work-related health has mainly focused on individual factors. The present study expands the focus by exploring the role of organizational characteristics of workplaces for different individual health outcomes. The aim of the study was to look at differences in relative effect of workplace variations on five health outcomes, and to explain those differences in health outcomes by organizational characteristics. The sample encompassed 90 workplaces in Sweden and about 4300 individuals employed within these workplaces. Measurement of the workplace characteristics was carried out independently of the measurement of the individual's working conditions and health. Organizational data were collected by interviews with local managers at participating workplaces, and individual data were obtained by means of a survey of the employees. The results showed that a significant proportion of the variance in sickness absence, work ability, general health, and musculoskeletal disorders was attributed to the workplace. Of eight tested organizational characteristics, customer adaptation, lean production, and performance control could explain some of this workplace variance. The results also showed that only one organizational effect remained significant when controlled for the individual confounder of age and gender. High customer adaptation is associated with higher sickness absence. This association is not mediated via differences in mental and physical job strain.

  8. 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.

  9. 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.

  10. Individual differences in language and working memory affect children's speech recognition in noise.

    Science.gov (United States)

    McCreery, Ryan W; Spratford, Meredith; Kirby, Benjamin; Brennan, Marc

    2017-05-01

    We examined how cognitive and linguistic skills affect speech recognition in noise for children with normal hearing. Children with better working memory and language abilities were expected to have better speech recognition in noise than peers with poorer skills in these domains. As part of a prospective, cross-sectional study, children with normal hearing completed speech recognition in noise for three types of stimuli: (1) monosyllabic words, (2) syntactically correct but semantically anomalous sentences and (3) semantically and syntactically anomalous word sequences. Measures of vocabulary, syntax and working memory were used to predict individual differences in speech recognition in noise. Ninety-six children with normal hearing, who were between 5 and 12 years of age. Higher working memory was associated with better speech recognition in noise for all three stimulus types. Higher vocabulary abilities were associated with better recognition in noise for sentences and word sequences, but not for words. Working memory and language both influence children's speech recognition in noise, but the relationships vary across types of stimuli. These findings suggest that clinical assessment of speech recognition is likely to reflect underlying cognitive and linguistic abilities, in addition to a child's auditory skills, consistent with the Ease of Language Understanding model.

  11. Vineyard microclimate and yield under different plastic covers

    Science.gov (United States)

    Holcman, Ester; Sentelhas, Paulo Cesar; Conceição, Marco Antônio Fonseca; Couto, Hilton Thadeu Zarate

    2017-12-01

    The use of plastic cover in vineyards minimizes effects of adverse weather conditions. The northwest of São Paulo State is one of the largest grape producing regions in Brazil; however, few studies investigate the effects of different plastic covers on vineyards in this region. This study compared the effect of black shading screen (BSS) and braided polypropylene film (BPF) on BRS Morena vineyard microclimate, grown on an overhead trellis system in the northwestern São Paulo. The experiments were carried out during three growing seasons (2012-2014). BSS allowed superior incoming solar radiation (SR) transmissivity, resulting in higher net radiation (Rn), and higher ratio between photosynthetically active (PAR) and SR. No differences were observed between the average air temperatures (T) and relative humidity (RH) of covered environments (BPF and BSS) and outside condition (automatic weather station-AWS), due to high air circulation, despite wind speed (WS) reduction caused by plastic covers. BPF provided better conditions for vineyard growth with higher fruit yield than vineyard under BSS regarding the number of shoots with bunches per plant, bunch and stem weights, longitudinal diameter of berries, quantity of fertile buds per shoot, and yield per shoot and per plant. BPF covers also influenced leaf size and growth speed of plants in vineyards.

  12. Gonadotropins studies in female egyptian subjects under different physiological conditions

    International Nuclear Information System (INIS)

    El-Nabarawy, F.S.; Megahed, Y.M.; Ibrahim, M.

    2002-01-01

    This study is concerned with the role of the hypothalamic hypophyseal regulatory hormonal mechanisms in the control of gonadal secretions in a selected normal egyptian female subjects with varying ages under different physiological conditions. The study allowed precise definition of the modulator influence of a number of key factors triggering appropriate alteration in circulating serum levels of FSH and LH determined by IRMA technique in pre-pubertal female children (9-11), post-pubertal adolescents females (13-16). Adult married females (27-33) and post-menopausal (58-63). The levels of FSH and LH were increased markedly with age but children less than 11 years old had only nocturnal increase in levels of FSH (p.O.I) and LH(P< 0.001). post-pubertal aged girls had significant nocturnal elevation only of LH levels (P< 0.001), adult married females did not exhibit significant difference in gonadotropin concentrations. whereas significant elevation in FSH and LH levels (P<0.001) in post-menopausal females were observed

  13. Dust growth under different plasma conditions in protoplanetary disks

    Science.gov (United States)

    Xiang, Chuchu; Matthews, Lorin; Carballido, Augusto; Hyde, Truell

    2017-10-01

    Coagulation of dust aggregates plays an important role in the formation of planets and the evolution of protoplanetary disks. As cosmic dust becomes charged in the radiative plasma environment, the trajectories of colliding dust grains can be altered by the electrostatic force acting between them, affecting their coagulation probability. This study compares the dust growth in protoplanetary disks with different turbulence strengths and different plasma conditions, i.e. the ratio of free electrons to free ions. A Monte Carlo approach with a simple kernel based on the radius of the grains is used to choose potential colliding pairs and calculate the elapsed time between collisions. The actual collision outcome is determined using a detailed model of the collision which takes into account the aggregate morphology, trajectory, orientation, and all forces acting on the colliding grains. A statistical analysis of the collision outcomes is used to determine collision probability as well as the physical characteristics of the resulting aggregates for both charged and uncharged grains. Preliminary results show that charged aggregates tend to be more porous than neutral particles, and more highly charged particles experience less restructuring as a result of gentler collisions. In regions with weak turbulence, both the collision rate and the number of bouncing collisions are lower for highly charged grains, and the probability of hit-and-stick collisions leading to aggregate growth is a balance of the collision and bouncing rates. This work was supported by the National Science Foundation under Grant PHY-1414523.

  14. Neospora caninum prevalence in dogs raised under different living conditions.

    Science.gov (United States)

    Nazir, Muhammad Mudasser; Maqbool, Azhar; Akhtar, Masood; Ayaz, Mazhar; Ahmad, Atif Nisar; Ashraf, Kamran; Ali, Asif; Alam, Muhammad Azhar; Ali, Muhammad Amjad; Khalid, Abdur Rauf; Lindsay, David S

    2014-08-29

    Neospora caninum is an important cause of abortion in dairy cattle worldwide. Dogs are important in the epidemiology of N. caninum because they act as definitive hosts shedding oocysts in the environment. Vertical transmission of the parasite is well recognized as an important aspect of the epidemiology of the parasite but the importance of horizontal transmission has been less studied. A N. caninum competitive ELISA was used to examine serum samples from 600 dogs that were raised under 4 different living conditions. Samples from 138 dogs living on 24 dairies with a prevalence (0-70%) of anti-N. caninum antibodies in the cattle, 294 pet dogs without neurological signs, 76 from pet dogs exhibiting neurological signs, and 92 stray dogs were examined. The overall seroprevalence of N. caninum was 23.5% (95% CI = ± 2.99) in the 600 dogs. Significant (P 0.05). The prevalence of N. caninum antibodies was not significantly (P>0.05) different in dogs based on breed. These findings suggest a relationship between N. caninum infection of dogs from dairies and cattle on these dairies. However, further research is required to determine what is the most important way dogs acquire infection and how to prevent dogs from shedding oocysts. Copyright © 2014 Elsevier B.V. All rights reserved.

  15. Spin dynamics of an individual Cr atom in a semiconductor quantum dot under optical excitation

    Energy Technology Data Exchange (ETDEWEB)

    Lafuente-Sampietro, A. [Université Grenoble Alpes, Institut Néel, F-38000 Grenoble (France); CNRS, Institut Néel, F-38000 Grenoble (France); Institute of Materials Science, University of Tsukuba, 305-8573 Tsukuba (Japan); Utsumi, H.; Kuroda, S. [Institute of Materials Science, University of Tsukuba, 305-8573 Tsukuba (Japan); Boukari, H.; Besombes, L., E-mail: lucien.besombes@grenoble.cnrs.fr [Université Grenoble Alpes, Institut Néel, F-38000 Grenoble (France); CNRS, Institut Néel, F-38000 Grenoble (France)

    2016-08-01

    We studied the spin dynamics of a Cr atom incorporated in a II-VI semiconductor quantum dot using photon correlation techniques. We used recently developed singly Cr-doped CdTe/ZnTe quantum dots to access the spin of an individual magnetic atom. Auto-correlation of the photons emitted by the quantum dot under continuous wave optical excitation reveals fluctuations of the localized spin with a timescale in the 10 ns range. Cross-correlation gives quantitative transfer time between Cr spin states. A calculation of the time dependence of the spin levels population in Cr-doped quantum dots shows that the observed spin dynamics is dominated by the exciton-Cr interaction. These measurements also provide a lower bound in the 20 ns range for the intrinsic Cr spin relaxation time.

  16. Gender differences in emotion experience perception under different facial muscle manipulations.

    Science.gov (United States)

    Wang, Yufeng; Zhang, Dongjun; Zou, Feng; Li, Hao; Luo, Yanyan; Zhang, Meng; Liu, Yijun

    2016-04-01

    According to embodied emotion theory, facial manipulations should modulate and initiate particular emotions. However, whether there are gender differences in emotion experience perception under different facial muscle manipulations is not clear. Therefore, we conducted two behavioral experiments to examine gender differences in emotional perception in response to facial expressions (sad, neutral, and happy) under three conditions: (1) holding a pen using only the teeth (HPT), which facilitates the muscles typically associated with smiling; (2) holding a pen using only the lips (HPL), which inhibits the muscles typically associated with smiling; and (3) a control condition--hold no pen (HNP). We found that HPT made the emotional feelings more positive, and that the change degree of female's ratings of sad facial expressions between conditions (HPL to HPT) was larger than males'. These results suggested cognition can be affected by the interaction of the stimuli and the body, especially the female. Copyright © 2016 Elsevier Inc. All rights reserved.

  17. Individual differences in neural responses to social rejection: the joint effect of self-esteem and attentional control.

    Science.gov (United States)

    Gyurak, Anett; Hooker, Christine I; Miyakawa, Asako; Verosky, Sara; Luerssen, Anna; Ayduk, Özlem N

    2012-03-01

    Individuals with low self-esteem have been found to react more negatively to signs of interpersonal rejection than those with high self-esteem. However, previous research has found that individual differences in attentional control can attenuate negative reactions to social rejection among vulnerable, low self-esteem individuals. The current fMRI study sought to elucidate the neurobiological substrate of this buffering effect. We hypothesized and found that while looking at scenes of social rejection (vs negative scenes) low self-esteem high attentional control individuals engaged the rostral anterior cingulate cortex (rACC), an area of the brain associated with emotional control, more than their low self-esteem low attentional control peers. Furthermore, we found that low self-esteem high attentional control individuals evaluated social rejection as less arousing and less rejecting in a separate behavioral task. Importantly, activation in the rACC fully mediated the relationship between the interaction of self-esteem and attentional control and emotional evaluations, suggesting that the rACC activation underlies the buffering effects of attentional control. Results are discussed in terms of individual differences in emotional vulnerability and protection and by highlighting the role of rACC in emotion regulation. © The Author (2011). Published by Oxford University Press.

  18. Gray matter volumes of early sensory regions are associated with individual differences in sensory processing.

    Science.gov (United States)

    Yoshimura, Sayaka; Sato, Wataru; Kochiyama, Takanori; Uono, Shota; Sawada, Reiko; Kubota, Yasutaka; Toichi, Motomi

    2017-12-01

    Sensory processing (i.e., the manner in which the nervous system receives, modulates, integrates, and organizes sensory stimuli) is critical when humans are deciding how to react to environmental demands. Although behavioral studies have shown that there are stable individual differences in sensory processing, the neural substrates that implement such differences remain unknown. To investigate this issue, structural magnetic resonance imaging scans were acquired from 51 healthy adults and individual differences in sensory processing were assessed using the Sensory Profile questionnaire (Brown et al.: Am J Occup Ther 55 (2001) 75-82). There were positive relationships between the Sensory Profile modality-specific subscales and gray matter volumes in the primary or secondary sensory areas for the visual, auditory, touch, and taste/smell modalities. Thus, the present results suggest that individual differences in sensory processing are implemented by the early sensory regions. Hum Brain Mapp 38:6206-6217, 2017. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

  19. 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.

  20. Current and Historical Antecedents of Individual Value Differences Across 195 Regions in Europe

    NARCIS (Netherlands)

    van Herk, H.; Poortinga, Y.H.

    2012-01-01

    This study analyzes differences on two value dimensions, conservation and self-enhancement, at both the individual and regional level across Europe. Within-country regions represent "cultunits" that often have belonged to different nation-states in history. Eight antecedent variables are explored.

  1. The Development of Children's Moral Sensibility: Individual Differences and Emotion Understanding.

    Science.gov (United States)

    Dunn, Judy; And Others

    1995-01-01

    Developmental changes and individual differences in children's conceptions of transgression were studied in 46 children from preschool through 1st grade. Differences in response to moral transgressions in kindergarten were related to mothers' control management and to siblings' friendly behavior in the preschool period, early understanding of…

  2. The Interplay of Individual Differences and Context of Learning in Behavioral and Neurocognitive Second Language Development

    Science.gov (United States)

    Faretta-Stutenberg, Mandy; Morgan-Short, Kara

    2018-01-01

    In order to understand variability in second language (L2) acquisition, this study addressed how individual differences in cognitive abilities may contribute to development for learners in different contexts. Specifically, we report the results of two short-term longitudinal studies aimed at examining the role of cognitive abilities in accounting…

  3. 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…

  4. 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,…

  5. 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…

  6. 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...

  7. Age, Memory Load, and Individual Differences in Working Memory as Determinants of Class-Inclusion Reasoning.

    Science.gov (United States)

    Rabinowitz, F. Michael; Howe, Mark L.; Saunders, Kelly

    2002-01-01

    This study examined effects of individual differences in speak-span scores and variations in memory demands on class-inclusion performance of 10-, 13-, and 15-year-olds. Results from regression analyses and the mathematical model indicated that differences in age, speak span, and memory load affected performance. Effects of speak span and memory…

  8. Internet use and online social support among same sex attracted individuals of different ages

    NARCIS (Netherlands)

    Baams, L.; Jonas, K.J.; Utz, S.; Bos, H.M.W.; van der Vuurst, L.

    2011-01-01

    The current research addressed age differences in internet use among Same Sex Attracted (SSA) individuals. In general, online communities are found to be a source of social support, especially for minority group members. However, it is unclear whether younger and older SSA people differ in their use

  9. Individual Differences and Learning Contexts: A Self-Regulated Learning Perspective

    Science.gov (United States)

    Ben-Eliyahu, Adar

    2017-01-01

    This article examines how individual differences (giftedness) interact with learning contexts (favorite versus least favorite courses) to influence learning processes and outcomes. The findings show that gifted and typically developing students differ solely in their expectancies for success and grades among a large variety of measures, including…

  10. A Noninvasive Approach to Determine Viscoelastic Properties of an Individual Adherent Cell under Fluid Flow

    Science.gov (United States)

    Qiu, Jun; Baik, Andrew D.; Lu, X. Lucas; Hillman, Elizabeth M. C.; Zhuang, Zhuo; Dong, Cheng; Guo, X. Edward

    2014-01-01

    Mechanical properties of cells play an important role in their interaction with the extracellular matrix as well as the mechanotransduction process. Several in vitro techniques have been developed to determine the mechanical properties of cells, but none of them can measure the viscoelastic properties of an individual adherent cell in fluid flow non-invasively. In this study, techniques of fluid-structure interaction (FSI) finite element method and quasi-3-dimensional (quasi-3D) cell microscopy were innovatively applied to the frequently used flow chamber experiment, where an adherent cell was subjected to fluid flow. A new non-invasive approach, with cells at close to physiological conditions, was established to determine the viscoelastic properties of individual cells. The results showed an instantaneous modulus of osteocytes of 0.49±0.11 kPa, an equilibrium modulus of 0.31±0.044 kPa, and an apparent viscosity coefficient of 4.07±1.23 kPa·s. This new quantitative approach not only provides an excellent means to measure cell mechanical properties, but also may help to elucidate the mechanotransduction mechanisms for a variety of cells under fluid flow stimulation. PMID:24581798

  11. Emergence of leadership in a robotic fish group under diverging individual personality traits.

    Science.gov (United States)

    Wang, Chen; Chen, Xiaojie; Xie, Guangming; Cao, Ming

    2017-05-01

    Variations of individual's personality traits have been identified before as one of the possible mechanisms for the emergence of leadership in an interactive collective, which may lead to benefits for the group as a whole. Complementing the large number of existing literatures on using simulation models to study leadership, we use biomimetic robotic fish to gain insight into how the fish's behaviours evolve under the influence of the physical hydrodynamics. In particular, we focus in this paper on understanding how robotic fish's personality traits affect the emergence of an effective leading fish in repeated robotic foraging tasks when the robotic fish's strategies, to push or not to push the obstacle in its foraging path, are updated over time following an evolutionary game set-up. We further show that the robotic fish's personality traits diverge when the group carries out difficult foraging tasks in our experiments, and self-organization takes place to help the group to adapt to the level of difficulties of the tasks without inter-individual communication.

  12. Individual differences in susceptibility to false memory in the Deese-Roediger-McDermott paradigm.

    Science.gov (United States)

    Watson, Jason M; Bunting, Michael F; Poole, Bradley J; Conway, Andrew R A

    2005-01-01

    The authors addressed whether individual differences in the working memory capacity (WMC) of young adults influence susceptibility to false memories for nonpresented critical words in the Deese-Roediger-McDermott associative list paradigm. The results of 2 experiments indicated that individuals with greater WMC recalled fewer critical words than individuals with reduced WMC when participants were forewarned about the tendency of associative lists (e.g., bed, rest, . . .) to elicit illusory memories for critical words (e.g., sleep). In contrast, both high and low WMC participants used repeated study-test trials to reduce recall of critical words. These findings suggest that individual differences in WMC influence cognitive control and the ability to actively maintain task goals in the face of interfering information or habit. 2005 APA

  13. Sensorimotor integration in dyslexic children under different sensory stimulations.

    Science.gov (United States)

    Viana, André R; Razuk, Milena; de Freitas, Paulo B; Barela, José A

    2013-01-01

    Dyslexic children, besides difficulties in mastering literacy, also show poor postural control that might be related to how sensory cues coming from different sensory channels are integrated into proper motor activity. Therefore, the aim of this study was to examine the relationship between sensory information and body sway, with visual and somatosensory information manipulated independent and concurrently, in dyslexic children. Thirty dyslexic and 30 non-dyslexic children were asked to stand as still as possible inside of a moving room either with eyes closed or open and either lightly touching a moveable surface or not for 60 seconds under five experimental conditions: (1) no vision and no touch; (2) moving room; (3) moving bar; (4) moving room and stationary touch; and (5) stationary room and moving bar. Body sway magnitude and the relationship between room/bar movement and body sway were examined. Results showed that dyslexic children swayed more than non-dyslexic children in all sensory condition. Moreover, in those trials with conflicting vision and touch manipulation, dyslexic children swayed less coherent with the stimulus manipulation compared to non-dyslexic children. Finally, dyslexic children showed higher body sway variability and applied higher force while touching the bar compared to non-dyslexic children. Based upon these results, we can suggest that dyslexic children are able to use visual and somatosensory information to control their posture and use the same underlying neural control processes as non-dyslexic children. However, dyslexic children show poorer performance and more variability while relating visual and somatosensory information and motor action even during a task that does not require an active cognitive and motor involvement. Further, in sensory conflict conditions, dyslexic children showed less coherent and more variable body sway. These results suggest that dyslexic children have difficulties in multisensory integration because

  14. 42 CFR 436.308 - Medically needy coverage of individuals under age 21.

    Science.gov (United States)

    2010-10-01

    ...) Individuals in foster homes or private institutions for whom a public agency is assuming a full or partial... individuals placed in foster homes or private institutions by private nonprofit agencies. (2) Individuals in...

  15. Reliabilities of Mental Rotation Tasks: Limits to the Assessment of Individual Differences

    Directory of Open Access Journals (Sweden)

    Gerrit Hirschfeld

    2013-01-01

    Full Text Available Mental rotation tasks with objects and body parts as targets are widely used in cognitive neuropsychology. Even though these tasks are well established to study between-groups differences, the reliability on an individual level is largely unknown. We present a systematic study on the internal consistency and test-retest reliability of individual differences in mental rotation tasks comparing different target types and orders of presentations. In total n=99 participants (n=63 for the retest completed the mental rotation tasks with hands, feet, faces, and cars as targets. Different target types were presented in either randomly mixed blocks or blocks of homogeneous targets. Across all target types, the consistency (split-half reliability and stability (test-retest reliabilities were good or acceptable both for intercepts and slopes. At the level of individual targets, only intercepts showed acceptable reliabilities. Blocked presentations resulted in significantly faster and numerically more consistent and stable responses. Mental rotation tasks—especially in blocked variants—can be used to reliably assess individual differences in global processing speed. However, the assessment of the theoretically important slope parameter for individual targets requires further adaptations to mental rotation tests.

  16. 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.

  17. Impact of different individual GNSS receiver antenna calibration models on geodetic positioning

    Science.gov (United States)

    Baire, Q.; Pottiaux, E.; Bruyninx, C.; Defraigne, P.; Aerts, W.; Legrand, J.; Bergeot, N.; Chevalier, J. M.

    2012-04-01

    Since April 2011, the igs08.atx antenna calibration model is used in the routine IGS (International GNSS Service) data analysis. The model includes mean robot calibrations to correct for the offset and phase center variations of the GNSS receiver antennas. These so-called "type" calibrations are means of the individual calibrations available for a specific antenna/radome combination. The GNSS data analysis performed within the EUREF Permanent Network (EPN) aims at being as consistent as possible with the IGS analysis. This also applies to the receiver antenna calibrations. However, when available, individual antenna calibrations are used within the EPN analysis instead of the "type" calibration. When these individual calibrations are unavailable, then the EPN analysis falls back to (type) calibrations identical as the ones used within the IGS (igs08.atx). The aim of this study is to evaluate the significance of the offset caused by using different receiver antenna calibration models on the station position. Using the PPP (Precise Point Positioning) technique, we first investigate the differences in positioning obtained when switching between individual antenna calibrations and type calibrations. We analyze the observations of the 43 EPN stations equipped with receiver antenna individually calibrated over the period covering from 2003 to 2010 and we show that these differences can reach up to 4 mm in horizontal and 10 mm in vertical. Secondly, we study the accuracy of the individual calibrations models and we evaluate the effect of different sets of individual calibrations on the positioning. For that purpose, we use the data from 6 GNSS stations equipped with an antenna which has been individually calibrated at two calibration facilities recognized by the IGS: GEO++ and Bonn institute.

  18. Intertrial Variability in the Premotor Cortex Accounts for Individual Differences in Peripersonal Space.

    Science.gov (United States)

    Ferri, Francesca; Costantini, Marcello; Huang, Zirui; Perrucci, Mauro Gianni; Ferretti, Antonio; Romani, Gian Luca; Northoff, Georg

    2015-12-16

    We live in a dynamic environment, constantly confronted with approaching objects that we may either avoid or be forced to address. A multisensory and sensorimotor interface, the peripersonal space (PPS), mediates every physical interaction between our body and the environment. Behavioral investigations show high variability in the extension of PPS across individuals, but there is a lack of evidence on the neural underpinnings of these large individual differences. Here, we used approaching auditory stimuli and fMRI to capture the individual boundary of PPS and examine its neural underpinnings. Precisely, we tested the hypothesis that intertrial variability (ITV) in brain regions coding PPS predicts individual differences of its boundary at the behavioral level. Selectively in the premotor cortex, we found that ITV, rather than trial-averaged amplitude, of BOLD responses to far rather than near dynamic stimuli predicts the individual extension of PPS. Our results provide the first empirical support for the relevance of ITV of brain responses for individual differences in human behavior. Peripersonal space (PPS) is a multisensory and sensorimotor interface mediating every physical interaction between the body and the environment. A major characteristic of the boundary of PPS in humans is the extremely high variability of its location across individuals. We show that interindividual differences in the extension of the PPS are predicted by variability of BOLD responses in the premotor cortex to far stimuli approaching our body. Our results provide the first empirical support to the relevance of variability of evoked responses for human behavior and its variance across individuals. Copyright © 2015 the authors 0270-6474/15/3516328-12$15.00/0.

  19. Behavioral pattern of Rohilkhandi kids under different feeding systems

    Directory of Open Access Journals (Sweden)

    Anjali Kumari

    2016-07-01

    Full Text Available Aim: The present study designed to evaluate the effect of different feeding systems on the behavior of local Rohilkhandi kids. Materials and Methods: A total of 21 growing goats (local goat of Rohilkhand region, weighing around 7-11 kg and aging 4-5 months, were used. These animals were kept in three groups. Group I was fed un-chopped green fodder in circular feeder (newly designed. Group II was fed un-chopped green fodder in linear feeder that was similar to the existing farm practice. Group III was fed chopped green fodder in linear feeder (modified version. Amount of concentrate and dry fodder fed was kept constant for all the three groups subject to equal increment in accordance with their increasing age. Adlibitum green fodder was made available to the animals. The experiment was conducted for 3 months. On-going behavior was recorded each day 4 h (2 h in the morning from 9:00 am to 11:00 am, after offering the feed, and same was repeated for 2 h in the afternoon, i.e., from 2:00 pm to 4:00 pm was made between 9 am and 5 pm. The individual behaviors, viz., feeding, drinking, lying down, ruminating, idling, butting, pressing, pushing, frontal clashing, and physical displacement at feed barrier (active and passive: Without physical contact of the goat were recorded using time-sampling method. Further, incidental activities such as defecation and urination were also recorded. Results: Among all the groups, butting, head to head, and pushing were the common agonistic behavior found but values did not differ significantly. The pushing while feeding was relatively less in Group II (0.22±0.04 min which differed significantly (p<0.05 from the other two groups. The idling time was found significantly (p<0.05 lower in Group II (1.68±0.21 as compared to Group I (4.67±0.52 and Group III (4.27±0.56. Time spent in rumination near the feeding trough as well as away from the feeding trough was also significantly higher in Group I (p<0.05 than the other

  20. CO2 EFFLUX IN VERTISOL UNDER DIFFERENT LAND USE SYSTEMS

    Directory of Open Access Journals (Sweden)

    Israel Cantu Silva

    2010-01-01

    Full Text Available Determinations of CO2 efflux, soil temperature and soil-water content in vertisols were monitored at least twice a week between July 2001 and January 2002. At each sampling date, two daily measurements (at 08:00 and 14:00 h local time, named as morning and afternoon, respectively were carried out. A dynamic closed chamber with a portable system EGM employing a infrared gas analyzer (IRGA and a soil chamber (SRC-1 were used to assess soil CO2 efflux throughout the experimental period from vertisols under different land uses in northeastern Mexico: Pasture (Dichanthium annulatum, Leucaena leucocephala in an alley cropping system, a native and undisturbed shrubland plot, a Eucalyptus microtheca plantation, and a Sorghum bicolor field. Results showed for the Eucalyptus and Pasture plots a highly significant and positive linear relationship between morning and afternoon soil respiration rate and soil temperature, while no significant relationship was found between soil temperature and soil respiration for the Leucaena, Sorghum nor the Shrubland plots. Soil temperature alone explained 68% of the variation in the CO2 efflux rate in Eucalyptus and 33% in Pasture. During the study period, average morning soil respiration rates for all land uses ranged from 0.7 (October to 8.4 mmol CO2 m-2 s-1 (August, while afternoon soil respiration rates ranged from 0.6 to 14.4 mmol CO2 m-2 s-1. Average morning and afternoon soil respiration rates showed the following decreasing CO2 efflux order among the five investigated land uses: Pasture>Shrubland>Leucaena>Eucalyptus>Sorghum; thus, the pasture plot showed the highest average morning and afternoon soil respiration rates; 3.5 and 5.0 mmol CO2 m-2 s-1, respectively. In contrast, the Sorghum plot showed the lowest average morning (1.9 and afternoon (2.5 mmol CO2 m-2 s-1 soil respiration rates. The Pasture and Shrubland, which are common livestock management practices in this region, contribute to more CO2 emissions

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

    Science.gov (United States)

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

    2014-09-01

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

  2. Psychosocial characteristics of adolescents with different profiles of individuation in relation to parents

    Directory of Open Access Journals (Sweden)

    Melita Puklek Levpušček

    2003-12-01

    Full Text Available Individuation in relation to parents represents an important developmental task during adolescence. The article focuses on the examination of different profiles of individuation in relation to parents and how these profiles manifest themselves in different periods of adolescence. We were also interested in the psychosocial characteristics that vary among adolescents with different profiles of individuation. The sample consisted of 593 adolescents in the age range of 13 to 18 years. The adolescents filled in the self-report questionnaires of individuation in relation to parents and friends, perceived parental behavior, and perceived self-efficacy in learning. They also reported about the frequency of psychological symptoms experienced in the last month. To identify the diverse groups of adolescents the scores on the scale of individuation in relation to parents were subjected to a cluster analysis. Finally, the four-cluster solution was chosen. The clusters were named: Good connectedness with parents with non-threatened autonomy, Highly harmonious relationship with parents with non-threatened autonomy, Cold relationship with parents with threatened autonomy and Ambivalent relationship with parents. The results confirmed the hypothesis, that most adolescents will be classified in the profiles of good relationship with parents with non-threatened autonomy. The results also showed that the combination of moderate emotional connectedness with parents, low parental idealization, ability to integrate autonomy and connectedness, low denial of dependency needs and low engulfment anxiety represent the most favorable individuation pattern for psychological adaptation of adolescents.

  3. Camouflage and individual variation in shore crabs (Carcinus maenas from different habitats.

    Directory of Open Access Journals (Sweden)

    Martin Stevens

    Full Text Available Camouflage is widespread throughout the natural world and conceals animals from predators in a vast range of habitats. Because successful camouflage usually involves matching aspects of the background environment, species and populations should evolve appearances tuned to their local habitat, termed phenotype-environment associations. However, although this has been studied in various species, little work has objectively quantified the appearances of camouflaged animals from different habitats, or related this to factors such as ontogeny and individual variation. Here, we tested for phenotype-environment associations in the common shore crab (Carcinus maenas, a species highly variable in appearance and found in a wide range of habitats. We used field surveys and digital image analysis of the colors and patterns of crabs found in four locations around Cornwall in the UK to quantify how individuals vary with habitat (predominantly rockpool, mussel bed, and mudflat. We find that individuals from sites comprising different backgrounds show substantial differences in several aspects of color and pattern, and that this is also dependent on life stage (adult or juvenile. Furthermore, the level of individual variation is dependent on site and life stage, with juvenile crabs often more variable than adults, and individuals from more homogenous habitats less diverse. Ours is the most comprehensive study to date exploring phenotype-environment associations for camouflage and individual variation in a species, and we discuss the implications of our results in terms of the mechanisms and selection pressures that may drive this.

  4. Motor unit potential morphology differences in individuals with non-specific arm pain and lateral epicondylitis

    Directory of Open Access Journals (Sweden)

    McLean Linda

    2008-12-01

    Full Text Available Abstract Background The pathophysiology of non-specific arm pain (NSAP is unclear and the diagnosis is made by excluding other specific upper limb pathologies, such as lateral epicondylitis or cervical radiculopathy. The purpose of this study was to determine: (i if the quantitative parameters related to motor unit potential morphology and/or motor unit firing patterns derived from electromyographic (EMG signals detected from an affected muscle of patients with NSAP are different from those detected in the same muscle of individuals with lateral epicondylitis (LE and/or control subjects and (ii if the quantitative EMG parameters suggest that the underlying pathophysiology in NSAP is either myopathic or neuropathic in nature. Methods Sixteen subjects with NSAP, 11 subjects with LE, eight subjects deemed to be at-risk for developing a repetitive strain injury, and 37 control subjects participated. A quantitative electromyography evaluation was completed using decomposition-based quantitative electromyography (DQEMG. Needle- and surface-detected EMG signals were collected during low-level isometric contractions of the extensor carpi radialis brevis (ECRB muscle. DQEMG was used to extract needle-detected motor unit potential trains (MUPTs, and needle-detected motor unit potential (MUP and surface detected motor unit potential (SMUP morphology and motor unit (MU firing rates were compared among the four groups using one-way analysis of variance (ANOVA. Post hoc analyses were performed using Tukey's pairwise comparisons. Results Significant group differences were found for all MUP variables and for MU firing rate (p p p p p Conclusion The size-related parameters suggest that the NSAP group had significantly smaller MUPs and SMUPs than the control and LE subjects. Smaller MUPs and SMUPs may be indicative of muscle fiber atrophy and/or loss. A prospective study is needed to confirm any causal relationship between smaller MUPs and SMUPs and NSAP as found

  5. Individual Differences in Subjective Utility and Risk Preferences: The Influence of Hedonic Capacity and Trait Anxiety

    Directory of Open Access Journals (Sweden)

    Jonathon R. Howlett

    2017-05-01

    Full Text Available Individual differences in decision-making are important in both normal populations and psychiatric conditions. Variability in decision-making could be mediated by different subjective utilities or by other processes. For example, while traditional economic accounts attribute risk aversion to a concave subjective utility curve, in practice other factors could affect risk behavior. This distinction may have important implications for understanding the biological basis of variability in decision-making and for developing interventions to improve decision-making. Another aspect of decision-making that may vary between individuals is the sensitivity of subjective utility to counterfactual outcomes (outcomes that could have occurred, but did not. We investigated decision-making in relation to hedonic capacity and trait anxiety, two traits that relate to psychiatric conditions but also vary in the general population. Subjects performed a decision-making task, in which they chose between low- and high-risk gambles to win 0, 20, or 40 points on each trial. Subjects then rated satisfaction after each outcome on a visual analog scale, indicating subjective utility. Hedonic capacity was positively associated with the subjective utility of winning 20 points but was not associated with the concavity of the subjective utility curve (constructed using the mean subjective utility of winning 0, 20, or 40 points. Consistent with economic theory, concavity of the subjective utility curve was associated with risk aversion. Hedonic capacity was independently associated with risk seeking (i.e., not mediated by the shape of the subjective utility curve, while trait anxiety was unrelated to risk preferences. Contrary to our expectations, counterfactual sensitivity was unrelated to hedonic capacity and trait anxiety. Nevertheless, trait anxiety was associated with a self-report measure of regret-proneness, suggesting that counterfactual influences may occur via a pathway

  6. Correcting for different use of the scale and the need for further analysis of individual differences in sensory analysis

    DEFF Research Database (Denmark)

    Romano, R.; Brockhoff, Per B.; Hersleth, M.

    2008-01-01

    in descriptive sensory analysis there exist individual differences between assessors giving intensity scores on a continuous scale for a number of sensory attributes. The present paper is a study of the importance of scaling effects. In particular, different ways of reducing such effects...... will be discussed: scaling by standardization, scaling by Ten Berge algorithm and scaling by assessor model. Another important question is how much information is left after scaling differences have been corrected for. The degree of systematic variability will be measured by three-way modelling of the residuals...

  7. Nitrous Oxides Ozone Destructiveness Under Different Climate Scenarios

    Science.gov (United States)

    Kanter, David R.; McDermid, Sonali P.

    2016-01-01

    Nitrous oxide (N2O) is an important greenhouse gas and ozone depleting substance as well as a key component of the nitrogen cascade. While emissions scenarios indicating the range of N2O's potential future contributions to radiative forcing are widely available, the impact of these emissions scenarios on future stratospheric ozone depletion is less clear. This is because N2O's ozone destructiveness is partially dependent on tropospheric warming, which affects ozone depletion rates in the stratosphere. Consequently, in order to understand the possible range of stratospheric ozone depletion that N2O could cause over the 21st century, it is important to decouple the greenhouse gas emissions scenarios and compare different emissions trajectories for individual substances (e.g. business-as-usual carbon dioxide (CO2) emissions versus low emissions of N2O). This study is the first to follow such an approach, running a series of experiments using the NASA Goddard Institute for Space Sciences ModelE2 atmospheric sub-model. We anticipate our results to show that stratospheric ozone depletion will be highest in a scenario where CO2 emissions reductions are prioritized over N2O reductions, as this would constrain ozone recovery while doing little to limit stratospheric NOx levels (the breakdown product of N2O that destroys stratospheric ozone). This could not only delay the recovery of the stratospheric ozone layer, but might also prevent a return to pre-1980 global average ozone concentrations, a key goal of the international ozone regime. Accordingly, we think this will highlight the importance of reducing emissions of all major greenhouse gas emissions, including N2O, and not just a singular policy focus on CO2.

  8. Moral values are associated with individual differences in regional brain volume

    Science.gov (United States)

    Lewis, G. J.; Kanai, R.; Bates, T. C.; Rees, G.

    2012-01-01

    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 prefrontal cortex 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. PMID:22571458

  9. [Individual differences in sense of direction and psychological stress associated with mobility in visually impaired people].

    Science.gov (United States)

    Matsunaka, Kumiko; Shibata, Yuki; Yamamoto, Toshikazu

    2008-08-01

    Study 1 investigated individual differences in spatial cognition amongst visually impaired students and sighted controls, as well as the extent to which visual status contributes to these individual differences. Fifty-eight visually impaired and 255 sighted university students evaluated their sense of direction via self-ratings. Visual impairment contributed to the factors associated with the use and understanding of maps, confirming that maps are generally unfamiliar to visually impaired people. The relationship between psychological stress associated with mobility and individual differences in sense of direction was investigated in Study 2. A stress checklist was administered to the 51 visually impaired students who participated in Study 1. Psychological stress level was related to understanding and use of maps, as well as orientation and renewal, that is, course correction after being got lost. Central visual field deficits were associated with greater mobility-related stress levels than peripheral visual field deficits.

  10. Production of tropical forage grasses under different shading levels

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    Francisco Eduardo Torres

    2017-12-01

    Full Text Available This study aimed to evaluate the forage production of three tropical forage grasses under different shading levels. The experiment was conducted in a greenhouse at Universidade Estadual de Mato Grosso do Sul, University Unit of Aquidauana (UEMS/UUA, in a soil classified as Ultisol sandy loam texture. The treatments consisted of three grasses species combinations (B. brizantha cv. Marandu, B. decumbens cv. Basilisck and Panicum maximum cv. Tanzania, submitted to four shading levels (0, 30, 50 and 75%, arranged in a completely randomized blocks design in a factorial 3 x 4, with eight replications. After harvest, the plants were separated into shoot and roots for determination of shoot fresh mass (SFM, shoot dry mass (SDM and roots dry mass production. After analysis of variance, the qualitative factor was subjected to comparison of averages by Tukey’s test, and the quantitative factor to analysis of polynomial regression, being interactions appropriately unfolded. It was verified that B. decumbens, by its linearly increasing production of forage and less decrease of root formation, is the most recommended for shading conditions compared to grasses Tanzania and Marandu.

  11. The consistency of individual differences in behaviour: temperature effects on antipredator behaviour in garter snakes.

    Science.gov (United States)

    Brodie; Russell

    1999-02-01

    Differences among individuals are necessary for natural selection to occur. The extent and expression of these differences can limit the power of selection to cause evolutionary change. When individuals inconsistently express a trait, selection is less powerful. Labile traits such as behaviour are most likely to be inconsistent in their expression, because of the substantial role of environmental factors in their immediate expression. Previous work has focused on the consistency, or repeatability, of individual behaviour across different environments or within a single environment; little is known about how repeatability within an environment changes across environments. To address this issue, we examined the consistency of antipredator behaviour in juvenile garter snakes in different thermal environments. A group of 59 laboratory-born garter snakes Thamnophis ordinoides, was repeatedly assayed for sprint speed, distance crawled, and number of reversals performed during flight and antipredator display. Antipredator display showed very little variation and could not be analysed. Each individual was tested three times at each of three temperatures chosen to span the range of temperatures that snakes encounter in the field (15, 22.5, 30 degrees C). Temperature had substantial effects on the average expression of each behaviour; snakes crawled more slowly, for shorter distances, and performed fewer reversals at cooler temperatures. Individuals showed significant consistency in their behaviour, and this consistency of expression was not affected by temperature. Copyright 1999 The Association for the Study of Animal Behaviour.

  12. 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.

  13. 42 CFR 435.308 - Medically needy coverage of individuals under age 21.

    Science.gov (United States)

    2010-10-01

    ... reasonable classifications are as follows: (1) Individuals in foster homes or private institutions for whom a... individuals, it may also provide Medicaid to individuals placed in foster homes or private institutions by private nonprofit agencies. (2) Individuals in adoptions subsidized in full or in part by a public agency...

  14. Near-infrared spectroscopy assessment of microvasculature detects difference in lower limb vascular responsiveness in obese compared to lean individuals.

    Science.gov (United States)

    Soares, Rogério Nogueira; Murias, Juan M

    2018-02-03

    Microvascular dysfunction is an early complication in obesity-related cardiovascular disease (CVD) that can lead to changes in hemodynamic function and endothelial cell expression throughout the vasculature that is vessel specific. This study aimed to evaluate whether the near-infrared spectroscopy (NIRS) combined with a vascular occlusion (VOT) assessment was capable of detecting differences in vascular responsiveness within the microvasculature of the lower limb between lean and obese individuals. Twenty lean (BMI = 21.6 ± 1.3) and 17 obese individuals (BMI = 33.9 ± 1.1) participated in the study. Individuals underwent a VOT (5 min of baseline, 5 min of occlusion, and 8 min following cuff release) and vascular responsiveness was evaluated by the Slope 2 (Slope 2 StO 2 ) and the area under the curve (StO 2AUC ) of oxygen saturation (StO 2 ) signal during reperfusion. The difference between the minimal and the maximal value of StO 2 was calculated as the Amplitude of the StO 2 response. The Slope 2 StO 2 of the obese individuals was smaller (0.68 ± 0.07%·s -1 ) than the Slope 2 StO 2 of the lean individuals (1.08 ± 0.13%·s -1 ;P lean individuals (1708 ± 168%·s -1 ; P lean ones (30.4 ± 2.9 vs 21.6 ± 1.3 StO 2 (%), respectively; P lean individuals (r = 0.745; P lean and obese individuals. Copyright © 2018 Elsevier Inc. All rights reserved.

  15. 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.

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

    Directory of Open Access Journals (Sweden)

    N.L. Vysochina

    2015-08-01

    Full Text Available Purpose: to determine significance of individualized approach during psychological training at different stages of many years’ perfection in tennis. The tasks of the research were studying of place and role of psychological component in general system of tennis players’ sport training as well as determination of specificities of individualized approach during 14-15 years old and elite tennis players’ psychological training. Material: In the research 24 experts, coaches of combined teams and clubs, elite tennis players took part. Results: Role of psychological training in general system of many years’ perfection has been determined. We also found out that individualization of psychological training in modern tennis is not paid sufficient attention to at present. Most of the questioned respondents pointed, that such training is conducted mainly with elite sportsmen (42%. Only 14% noted that individual psychological training is carried out at basic stages of many years’ perfection. Conclusions: Principle of individualization is a determining one in the course of sportsmen’s training at stages of many years’ perfection. About 86% of experts stressed on significance of application of individualized approach in work with tennis players. Consideration of tennis players’ individual features during psychological training is a compulsory matter in increasing of effectiveness of sportsmen’s training and competition functioning.

  17. Working through the pain: working memory capacity and differences in processing and storage under pain.

    Science.gov (United States)

    Sanchez, Christopher A

    2011-02-01

    It has been suggested that pain perception and attention are closely linked at both a neural and a behavioural level. If pain and attention are so linked, it is reasonable to speculate that those who vary in working memory capacity (WMC) should be affected by pain differently. This study compares the performance of individuals who differ in WMC as they perform processing and memory span tasks while under mild pain and not. While processing performance under mild pain does not interact with WMC, the ability to store information for later recall does. This suggests that pain operates much like an additional processing burden, and that the ability to overcome this physical sensation is related to differences in WMC. © 2011 Psychology Press, an imprint of the Taylor & Francis Group, an Informa business

  18. 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.

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

    Science.gov (United States)

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

    2009-08-01

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

  20. 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.

  1. Inter-Individual Differences in RNA Levels in Human Peripheral Blood

    Science.gov (United States)

    Chomczynski, Piotr; Wilfinger, William W.; Eghbalnia, Hamid R.; Kennedy, Amy; Rymaszewski, Michal; Mackey, Karol

    2016-01-01

    Relatively little is known about the range of RNA levels in human blood. This report provides assessment of peripheral blood RNA level and its inter-individual differences in a group of 35 healthy humans consisting of 25 females and 10 males ranging in age from 50 to 89 years. In this group, the average total RNA level was 14.59 μg/ml of blood, with no statistically significant difference between females and males. The individual RNA level ranged from 6.7 to 22.7 μg/ml of blood. In healthy subjects, the repeated sampling of an individual’s blood showed that RNA level, whether high or low, was stable. The inter-individual differences in RNA level in blood can be attributed to both, differences in cell number and the amount of RNA per cell. The 3.4-fold range of inter-individual differences in total RNA levels, documented herein, should be taken into account when evaluating the results of quantitative RT-PCR and/or RNA sequencing studies of human blood. Based on the presented results, a comprehensive assessment of gene expression in blood should involve determination of both the amount of mRNA per unit of total RNA (U / ng RNA) and the amount of mRNA per unit of blood (U / ml blood) to assure a thorough interpretation of physiological or pathological relevance of study results. PMID:26863434

  2. 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.

  3. 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.

  4. Tracking functional brain changes in patients with depression under psychodynamic psychotherapy using individualized stimuli.

    Directory of Open Access Journals (Sweden)

    Daniel Wiswede

    Full Text Available OBJECTIVE: Neurobiological models of depression posit limbic hyperactivity that should normalize after successful treatment. For psychotherapy, though, brain changes in patients with depression show substantial variability. Two critical issues in relevant studies concern the use of unspecific stimulation experiments and relatively short treatment protocols. Therefore changes in brain reactions to individualized stimuli were studied in patients with depression after eight months of psychodynamic psychotherapy. METHODS: 18 unmedicated patients with recurrent major depressive disorder were confronted with individualized and clinically derived content in a functional MRI experiment before (T1 and after eight months (T2 of psychodynamic therapy. A control group of 17 healthy subjects was also tested twice without intervention. The experimental stimuli were sentences describing each participant's dysfunctional interpersonal relationship patterns derived from clinical interviews based on Operationalized Psychodynamic Diagnostics (OPD. RESULTS: At T1 patients showed enhanced activation compared to controls in several limbic and subcortical regions, including amygdala and basal ganglia, when confronted with OPD sentences. At T2 the differences in brain activity between patients and controls were no longer apparent. Concurrently, patients had improved significantly in depression scores. CONCLUSIONS: Using ecologically valid stimuli, this study supports the model of limbic hyperactivity in depression that normalizes after treatment. Without a control group of untreated patients measured twice, though, changes in patients' brain activity could also be attributed to other factors than psychodynamic therapy.

  5. Are the cause(s) responsible for urban-rural differences in schizophrenia risk rooted in families or individuals?

    DEFF Research Database (Denmark)

    Pedersen, Carsten Bøcker; Mortensen, Preben Bo

    2006-01-01

    evaluated whether the nearest older sibling's place of birth had an independent effect on schizophrenia risk. If the cause(s) responsible for the urban-rural differences are rooted in individuals only, the nearest older sibling's place of birth should have no independent effect. In this analysis......, the nearest older sibling's place of birth had an independent effect; among persons who lived in a rural area during their first 15 years of life, the relative risk was 1.59 (95% confidence interval: 1.10, 2.30) if their nearest older sibling had been born in the capital area as compared with a rural area......Many studies have identified urban-rural differences in schizophrenia risk. Hypothetical underlying cause(s) may include toxic exposures, diet, infections, and selective migration. The authors investigated whether the underlying cause(s) responsible for the urban-rural differences were rooted...

  6. Degradation of hydrocarbons under methanogenic conditions in different geosystems

    Science.gov (United States)

    Straaten, Nontje; Jiménez García, Núria; Richnow, Hans-Hermann; Krueger, Martin

    2014-05-01

    With increasing energy demand the search for new resources is becoming increasingly important for the future energy supply. Therefore the knowledge about fossil fuels like oil or natural gas and their extraction should be expanded. Biodegraded oil is found in many reservoirs worldwide. Consequently, it is very important to get insight in the microbial communities and metabolic processes involved in hydrocarbon degradation. Due to the lack of alternative electron acceptors in hydrocarbon-rich geosystems, degradation often takes place under methanogenic conditions. The aim of the present study is to identify the microorganisms and mechanisms involved in the degradation of complex hydrocarbons, like BTEX and polycyclic aromatic hydrocarbons, using culture dependent and independent techniques. For this purpose enrichment cultures from marine sediments, shales, coal and oil reservoirs are monitored for their capability to degrade alkanes and aromatic compounds. Moreover the environmental samples of these different geosystems analysed for evidence for the in situ occurrence of methanogenic oil degradation. The gas geochemical data provided in several cases hints for a recent biological origin of the methane present. First results of the microbial community analysis showed in environmental samples and enrichment cultures the existence of Bacteria known to degrade hydrocarbons. Also a diverse community of methanogenic Archaea could be found in the clone libraries. Additionally, in oil and coal reservoir samples the degradation of model hydrocarbons, e.g. methylnaphthalene, hexadecane and BTEX, to CH4 was confirmed by 13C-labeling. To explore the mechanisms involved in biodegradation, the enrichments as well as the original environmental samples are further analysed for the presence of respective functional genes.

  7. SOIL FUNGISTASIS AGAINST FUSARIUM GRAMINEARUM UNDER DIFFERENT CROP MANAGEMENT SYSTEMS

    Directory of Open Access Journals (Sweden)

    Bruno Brito Lisboa

    2015-02-01

    Full Text Available Soil management, in terms of tillage and cropping systems, strongly influences the biological properties of soil involved in the suppression of plant diseases. Fungistasis mediated by soil microbiota is an important component of disease-suppressive soils. We evaluated the influence of different management systems on fungistasis against Fusarium graminearum, the relationship of fungistasis to the bacterial profile of the soil, and the possible mechanisms involved in this process. Samples were taken from a long-term experiment set up in a Paleudult soil under conventional tillage or no-tillage management and three cropping systems: black oat (Avena strigose L. + vetch (Vicia sativa L./maize (Zea mays L. + cowpea (Vigna sinensis L., black oat/maize, and vetch/maize. Soil fungistasis was evaluated in terms of reduction of radial growth of F. graminearum, and bacterial diversity was assessed using ribosomal intergenic spacer analysis (RISA. A total of 120 bacterial isolates were obtained and evaluated for antibiosis, and production of volatile compounds and siderophores. No-tillage soil samples showed the highest level of F. graminearum fungistasis by sharply reducing the development of this pathogen. Of the cropping systems tested, the vetch + black oat/maize + cowpea system showed the highest fungistasis and the oat/maize system showed the lowest. The management system also affected the genetic profile of the bacteria isolated, with the systems from fungistatic soils showing greater similarity. Although there was no clear relationship between soil management and the characteristics of the bacterial isolates, we may conclude that antibiosis and the production of siderophores were the main mechanisms accounting for fungistasis.

  8. Different neurophysiological mechanisms underlying word and rule extraction from speech.

    Directory of Open Access Journals (Sweden)

    Ruth De Diego Balaguer

    Full Text Available The initial process of identifying words from spoken language and the detection of more subtle regularities underlying their structure are mandatory processes for language acquisition. Little is known about the cognitive mechanisms that allow us to extract these two types of information and their specific time-course of acquisition following initial contact with a new language. We report time-related electrophysiological changes that occurred while participants learned an artificial language. These changes strongly correlated with the discovery of the structural rules embedded in the words. These changes were clearly different from those related to word learning and occurred during the first minutes of exposition. There is a functional distinction in the nature of the electrophysiological signals during acquisition: an increase in negativity (N400 in the central electrodes is related to word-learning and development of a frontal positivity (P2 is related to rule-learning. In addition, the results of an online implicit and a post-learning test indicate that, once the rules of the language have been acquired, new words following the rule are processed as words of the language. By contrast, new words violating the rule induce syntax-related electrophysiological responses when inserted online in the stream (an early frontal negativity followed by a late posterior positivity and clear lexical effects when presented in isolation (N400 modulation. The present study provides direct evidence suggesting that the mechanisms to extract words and structural dependencies from continuous speech are functionally segregated. When these mechanisms are engaged, the electrophysiological marker associated with rule-learning appears very quickly, during the earliest phases of exposition to a new language.

  9. Haematology of the west African dwarf sheep under two different ...

    African Journals Online (AJOL)

    The haematological parameters of the West African Dwarf (WAD) sheep under intensive and extensive management systems in Nigeria were determined. The intensively reared animals showed higher (P<0.001) Packed Cell Volume haemoglobin concentration and mean corpuscular volume (P<0.01) than those under ...

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

    Directory of Open Access Journals (Sweden)

    Ipek Bozkurt

    2015-01-01

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

  11. The composition of secondary amorphous phases under different environmental conditions

    Science.gov (United States)

    Smith, R.; Rampe, E. B.; Horgan, B. H. N.; Dehouck, E.; Morris, R. V.

    2017-12-01

    X-ray diffraction (XRD) patterns measured by the CheMin instrument on the Mars Science Laboratory Curiosity rover demonstrate that amorphous phases are major components ( 15-60 wt%) of all rock and soil samples in Gale Crater. The nature of these phases is not well understood and could be any combination of primary (e.g., glass) and secondary (e.g., silica, ferrihydrite) phases. Secondary amorphous phases are frequently found as weathering products in soils on Earth, but these materials remain poorly characterized. Here we study a diverse suite of terrestrial samples including: sediments from recently de-glaciated volcanoes (Oregon), modern volcanic soils (Hawaii), and volcanic paleosols (Oregon) in order to determine how formation environment, climate, and diagenesis affect the abundance and composition of amorphous phases. We combine bulk XRD mineralogy with bulk chemical compositions (XRF) to calculate the abundance and bulk composition of the amorphous materials in our samples. We then utilize scanning transmission electron microscopy (STEM) and energy dispersive x-ray spectroscopy (EDS) to study the composition of individual amorphous phases at the micrometer scale. XRD analyses of 8 samples thus far indicate that the abundance of amorphous phases are: modern soils (20-80 %) > paleosols (15-40 %) > glacial samples (15-30 %). Initial calculations suggest that the amorphous components consist primarily of SiO2, Al2O3, TiO2, FeO and Fe2O3, with minor amounts of other oxides (e.g., MgO, CaO, Na2O). Compared to their respective crystalline counterparts, calculations indicate bulk amorphous components enriched in SiO2 for the glacial sample, and depleted in SiO2 for the modern soil and paleosol samples. STEM analyses reveal that the amorphous components consist of a number of different phases. Of the two samples analyzed using STEM thus far, the secondary amorphous phases have compositions with varying ratios of SiO2, Al2O3, TiO2, and Fe-oxides, consistent with mass

  12. Dissipation of oxytetracycline in soils under different redox conditions

    International Nuclear Information System (INIS)

    Yang Jigeng; Ying Guangguo; Zhou Lijun; Liu Shan; Zhao Jianliang

    2009-01-01

    This study investigated the dissipation kinetics of oxytetracycline in soils under aerobic and anoxic conditions. Laboratory experiments showed that the dissipation of oxytetracycline in soil followed first-order reaction kinetics and its dissipation rates decreased with increasing concentration. Oxytetracycline dissipated faster in soil under aerobic conditions than under anoxic conditions. The half-lives for oxytetracycline in soil under aerobic conditions ranged between 29 and 56 days for non-sterile treatments and 99-120 days for sterile treatments, while under anoxic conditions the half-lives of oxytetracycline ranged between 43 and 62 days in the non-sterile soil and between 69 and 104 days in the sterile soil. This suggests microbes can degrade oxytetracycline in agricultural soil. Abiotic factors such as strong sorption onto soil components also played a role in the dissipation of oxytetracycline in soil. - Oxytetracycline dissipation in soils is influenced by redox conditions and soil properties.

  13. 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.

  14. Behavioral Landscapes and Earth Mover's Distance: A New Approach for Studying Individual Differences in Density Distributions.

    Science.gov (United States)

    Ram, Nilam; Benson, Lizbeth; Brick, Timothy R; Conroy, David E; Pincus, Aaron L

    2017-08-01

    Contemporary views of personality highlight intraindividual variability. We forward a general method for quantifying individual differences in behavioral tendencies based on Earth Mover's Distance. Using data from 150 individuals who reported on their and others' interpersonal behavior in 64,112 social interactions, we illustrate how this new approach can advance notions of personality as density distributions. Results provide independent confirmation and establish validity of existing representations of individual differences in interpersonal behavior, and identify new dimensions and profiles of personality and well-being. Benefits of the EMD method include freedom from assumptions about the shape and form of density distributions, generality of application to n-dimensional behavior captured in experience sampling studies, and natural integration of personality structure and dynamics.

  15. Clear signals or mixed messages: inter-individual emotion congruency modulates brain activity underlying affective body perception

    Science.gov (United States)

    de Gelder, B.

    2016-01-01

    The neural basis of emotion perception has mostly been investigated with single face or body stimuli. However, in daily life one may also encounter affective expressions by groups, e.g. an angry mob or an exhilarated concert crowd. In what way is brain activity modulated when several individuals express similar rather than different emotions? We investigated this question using an experimental design in which we presented two stimuli simultaneously, with same or different emotional expressions. We hypothesized that, in the case of two same-emotion stimuli, brain activity would be enhanced, while in the case of two different emotions, one emotion would interfere with the effect of the other. The results showed that the simultaneous perception of different affective body expressions leads to a deactivation of the amygdala and a reduction of cortical activity. It was revealed that the processing of fearful bodies, compared with different-emotion bodies, relied more strongly on saliency and action triggering regions in inferior parietal lobe and insula, while happy bodies drove the occipito-temporal cortex more strongly. We showed that this design could be used to uncover important differences between brain networks underlying fearful and happy emotions. The enhancement of brain activity for unambiguous affective signals expressed by several people simultaneously supports adaptive behaviour in critical situations. PMID:27025242

  16. Clear signals or mixed messages: inter-individual emotion congruency modulates brain activity underlying affective body perception.

    Science.gov (United States)

    de Borst, A W; de Gelder, B

    2016-08-01

    The neural basis of emotion perception has mostly been investigated with single face or body stimuli. However, in daily life one may also encounter affective expressions by groups, e.g. an angry mob or an exhilarated concert crowd. In what way is brain activity modulated when several individuals express similar rather than different emotions? We investigated this question using an experimental design in which we presented two stimuli simultaneously, with same or different emotional expressions. We hypothesized that, in the case of two same-emotion stimuli, brain activity would be enhanced, while in the case of two different emotions, one emotion would interfere with the effect of the other. The results showed that the simultaneous perception of different affective body expressions leads to a deactivation of the amygdala and a reduction of cortical activity. It was revealed that the processing of fearful bodies, compared with different-emotion bodies, relied more strongly on saliency and action triggering regions in inferior parietal lobe and insula, while happy bodies drove the occipito-temporal cortex more strongly. We showed that this design could be used to uncover important differences between brain networks underlying fearful and happy emotions. The enhancement of brain activity for unambiguous affective signals expressed by several people simultaneously supports adaptive behaviour in critical situations. © The Author (2016). Published by Oxford University Press. For Permissions, please email: journals.permissions@oup.com.

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

    Science.gov (United States)

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

    2016-01-01

    In this paper, we investigate whether individual differences in performance on heuristic and biases tasks can be explained by cognitive abilities, monitoring confidence, and control thresholds. Current theories explain individual differences in these tasks by the ability to detect errors and override automatic but biased judgments, and deliberative cognitive abilities that help to construct the correct response. Here we retain cognitive abilities but disentangle error detection, proposing that lower monitoring confidence and higher control thresholds promote error checking. Participants (N = 250) completed tasks assessing their fluid reasoning abilities, stable monitoring confidence levels, and the control threshold they impose on their decisions. They also completed seven typical heuristic and biases tasks such as the cognitive reflection test and Resistance to Framing. Using structural equation modeling, we found that individuals with higher reasoning abilities, lower monitoring confidence, and higher control threshold performed significantly and, at times, substantially better on the heuristic and biases tasks. Individuals with higher control thresholds also showed lower preferences for risky alternatives in a gambling task. Furthermore, residual correlations among the heuristic and biases tasks were reduced to null, indicating that cognitive abilities, monitoring confidence, and control thresholds accounted for their shared variance. Implications include the proposal that the capacity to detect errors does not differ between individuals. Rather, individuals might adopt varied strategies that promote error checking to different degrees, regardless of whether they have made a mistake or not. The results support growing evidence that decision-making involves cognitive abilities that construct actions and monitoring and control processes that manage their initiation. PMID:27790170

  18. 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.

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

    Science.gov (United States)

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

    2016-01-01

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

  20. Imaging genetics and the neurobiological basis of individual differences in vulnerability to addiction.

    Science.gov (United States)

    Sweitzer, Maggie M; Donny, Eric C; Hariri, Ahmad R

    2012-06-01

    Addictive disorders are heritable, but the search for candidate functional polymorphisms playing an etiological role in addiction is hindered by complexity of the phenotype and the variety of factors interacting to impact behavior. Advances in human genome sequencing and neuroimaging technology provide an unprecedented opportunity to explore the impact of functional genetic variants on variability in behaviorally relevant neural circuitry. Here, we present a model for merging these technologies to trace the links between genes, brain, and addictive behavior. We describe imaging genetics and discuss the utility of its application to addiction. We then review data pertaining to impulsivity and reward circuitry as an example of how genetic variation may lead to variation in behavioral phenotype. Finally, we present preliminary data relating the neural basis of reward processing to individual differences in nicotine dependence. Complex human behaviors such as addiction can be traced to their basic genetic building blocks by identifying intermediate behavioral phenotypes, associated neural circuitry, and underlying molecular signaling pathways. Impulsivity has been linked with variation in reward-related activation in the ventral striatum (VS), altered dopamine signaling, and functional polymorphisms of DRD2 and DAT1 genes. In smokers, changes in reward-related VS activation induced by smoking abstinence may be associated with severity of nicotine dependence. Variation in genes related to dopamine signaling may contribute to heterogeneity in VS sensitivity to reward and, ultimately, to addiction. These findings illustrate the utility of the imaging genetics approach for investigating the neurobiological basis for vulnerability to addiction. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

  1. Imaging genetics and the neurobiological basis of individual differences in vulnerability to addiction*

    Science.gov (United States)

    Sweitzer, Maggie M.; Donny, Eric C.; Hariri, Ahmad R.

    2012-01-01

    Background Addictive disorders are heritable, but the search for candidate functional polymorphisms playing an etiological role in addiction is hindered by complexity of the phenotype and the variety of factors interacting to impact behavior. Advances in human genome sequencing and neuroimaging technology provide an unprecedented opportunity to explore the impact of functional genetic variants on variability in behaviorally relevant neural circuitry. Here, we present a model for merging these technologies to trace the links between genes, brain, and addictive behavior. Methods We describe imaging genetics and discuss the utility of its application to addiction. We then review data pertaining to impulsivity and reward circuitry as an example of how genetic variation may lead to variation in behavioral phenotype. Finally, we present preliminary data relating the neural basis of reward processing to individual differences in nicotine dependence. Results Complex human behaviors such as addiction can be traced to their basic genetic building blocks by identifying intermediate behavioral phenotypes, associated neural circuitry, and underlying molecular signaling pathways. Impulsivity has been linked with variation in reward-related activation in the ventral striatum (VS), altered dopamine signaling, and functional polymorphisms of DRD2 and DAT1 genes. In smokers, changes in reward-related VS activation induced by smoking abstinence may be associated with severity of nicotine dependence. Conclusions Variation in genes related to dopamine signaling may contribute to heterogeneity in VS sensitivity to reward and, ultimately, to addiction. These findings illustrate the utility of the imaging genetics approach for investigating the neurobiological basis for vulnerability to addiction. PMID:22342427

  2. 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…

  3. Pre-trauma individual differences in extinction learning predict posttraumatic stress

    NARCIS (Netherlands)

    Lommen, M.J.J.; Engelhard, I.M.; Sijbrandij, M.; van Hout, M.A.; Hermans, D.

    2013-01-01

    In the aftermath of a traumatic event, many people suffer from psychological distress, but only a minority develops posttraumatic stress disorder (PTSD). Pre-trauma individual differences in fear conditioning, most notably reduced extinction learning, have been proposed as playing an important role

  4. Individualism, Collectivism, and Client Expression of Different Emotions: Their Relations to Perceived Counselor Effectiveness

    Science.gov (United States)

    Seo, Young Seok

    2011-01-01

    This study examined how individualism, collectivism, and counselor emphasis of different client emotions were related to perceived counselor effectiveness. Data were collected from 192 (122 women and 70 men) Korean students attending a large university in South Korea and from 170 (115 women and 55 men) American students attending a large…

  5. Investigating the Individual Difference Antecedents of Perceived Enjoyment in Students' Use of Blogging

    Science.gov (United States)

    Wang, Yi-Shun; Lin, Hsin-Hui; Liao, Yi-Wen

    2012-01-01

    With the proliferation of weblogs (blogs) used in educational contexts, gaining a better understanding of why students are willing to blog has become an important topic for practitioners and academics. The main purpose of this study is to explore the individual difference antecedents of perceived enjoyment and examine how they influence blogging…

  6. Officer Individual Differences: Predicting Long-Term Continuance and Performance in the U.S. Army

    Science.gov (United States)

    2012-10-01

    2009), work satisfaction ( Capon , Chernyshenko, & Stark, 2007; Johnson, Sachau, & Englert, 2010), organizational identification (Johnson, et al ...2010), educational and leadership opportunities (Young et al ., 2010), as well as patriotism and commitment to the Army ( Capon et al ., 2007; Gade...individual differences predictive of retention and promotion that are concomitant with continuance in the Army. Capon et al . (2007) argued that

  7. 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

    Scale range differences between individual assessors will often constitute a non-trivial part of the assessor-by-product interaction in sensory profile data (Brockhoff, 2003, 1998; Brockhoff and Skovgaard, 1994). We suggest a new mixed model ANOVA analysis approach, the Mixed Assessor Model (MAM...

  8. 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…

  9. Who Learns Best with Multiple Representations? Cognitive Theory Implications for Individual Differences in Multimedia Learning.

    Science.gov (United States)

    Moreno, Roxana

    This paper presents a cognitive theory of multimedia learning from which predictions on individual differences in learning are derived and tested. Elementary students learned how to add and subtract integers with an interactive multimedia game that included visual and symbolic representations of the arithmetic procedure. They learned either with…

  10. Individual Differences in Responses to Social Influence Attempts: Theory and Research on the Effects of Misanthropy.

    Science.gov (United States)

    Alvaro, Eusebio M.; Burgoon, Michael

    1995-01-01

    Finds support for eight theoretically derived hypotheses concerning how highly misanthropic individuals respond differently to influence attempts, and concerning the positive relationship between misanthropy and the avoidance of health care. Shows that respondents high in misanthropy report higher actual incidence of stress-related diseases. (SR)

  11. Individual Differences in Emotional Reactivity and Academic Achievement: A Psychophysiological Study

    Science.gov (United States)

    Scrimin, Sara; Altoè, Gianmarco; Moscardino, Ughetta; Pastore, Massimiliano; Mason, Lucia

    2016-01-01

    Factors related to grade point average (GPA) are of great importance for students' success. Yet, little is known about the impact of individual differences in emotional reactivity on students' academic performance. We aimed to examine the emotional reactivity-GPA link and to assess whether self-esteem and psychological distress moderate this…

  12. Individual Differences in Self-Efficacy Development: The Effects of Goal Orientation and Affectivity

    Science.gov (United States)

    Gerhardt, Megan W.; Brown, Kenneth G.

    2006-01-01

    This study examined the moderating role of the individual differences of goal orientation and affectivity on self-efficacy development. Consistent with hypotheses, results indicate that both positive and negative affectivity moderate the impact of an enactive mastery training program on efficacy development, with those higher in positive…

  13. Peer Victimization and Aggression: Moderation by Individual Differences in Salivary Cortisol and Alpha-Amylase

    Science.gov (United States)

    Rudolph, Karen D.; Troop-Gordon, Wendy; Granger, Douglas A.

    2010-01-01

    This research examined whether variations in salivary measures of the hypothalamic-pituitary-adrenal axis (cortisol) and autonomic nervous system (alpha amylase [sAA]) contribute to individual differences in the association between peer victimization and aggression. Children (N = 132; M age = 9.46 years, SD = 0.33) completed a measure of peer…

  14. Orthographic Consistency and Individual Learner Differences in Second Language Literacy Acquisition

    Science.gov (United States)

    Kim, Sun-A; Packard, Jerome; Christianson, Kiel; Anderson, Richard C.; Shin, Jeong-Ah

    2016-01-01

    This study investigated whether orthographic consistency and individual learner differences including working memory (WM), first language (L1) background, and second language (L2) proficiency affect Chinese L2 learners' literacy acquisition. Seventy American college students in beginning or intermediate Chinese classes participated in a character…

  15. Individual differences in cortisol responses to fear and frustration during middle childhood.

    Science.gov (United States)

    Lopez-Duran, Nestor L; Hajal, Nastassia J; Olson, Sheryl L; Felt, Barbara T; Vazquez, Delia M

    2009-07-01

    The purpose of this study was to examine individual differences in the activation and regulation of the hypothalamic-pituitary-adrenal (HPA) axis in prepubertal children after exposure to two different stress modalities and to evaluate the utility of an individual differences approach to the examination of HPA axis functioning. After a 30-min controlled baseline period, 73 7-year-olds (40 boys and 33 girls) were randomly assigned to a validity check condition or one of two experimental tasks designed to elicit fear or frustration. This was followed by a 60-min controlled regulation phase. A total of 17 saliva samples were collected, including 12 poststress samples at 5-min intervals. There was a significant stress modality effect, with children exposed to the fear condition reaching peak cortisol levels at 25min poststress and those exposed to the frustration condition reaching peak levels at 45min poststress. There was no difference in peak cortisol levels between the stress modalities. Individual variability across conditions was significant, with participants reaching peak levels as early as 10min poststress and as late as 60min poststress. Our data suggest that analysis of individual curves prior to making group-level comparisons may improve the explanatory power of HPA axis behavior models.

  16. Individual differences in cortisol responses to fear and frustration in middle childhood

    Science.gov (United States)

    Lopez-Duran, Nestor L.; Hajal, Nastassia J.; Olson, Sheryl L.; Felt, Barbara T.; Vazquez, Delia M.

    2009-01-01

    The purpose of this study was to examine individual differences in the activation and regulation of the Hypothalamic-Pituitary-Adrenal (HPA) Axis in pre-pubertal children after exposure to two different stress modalities, and to evaluate the utility of an individual differences approach to the examination of HPA-axis functioning. After a 30 minute controlled baseline period, 73 seven-year-old children (40 males and 33 females) were randomly assigned to a validity check condition, or one of two experimental tasks designed to elicit fear or frustration. This was followed by a 60-minute controlled regulation phase. A total of 17 saliva samples were collected, including 12 post-stress samples at 5-minute intervals. There was a significant stress modality effect, with children exposed to the fear condition reaching peak cortisol levels at 25 minutes post-stress, while those exposed to the frustration condition reached peak levels at 45 minutes post-stress. There was no difference in peak cortisol levels between the stress modalities. Individual variability across conditions was significant with subjects reaching peak levels as early as 10 minutes post-stress and as late as 60 minutes post-stress. Our data suggest that analysis of individual curves prior to making group level comparisons may improve the explanatory power of HPA-axis-behavior models. PMID:19410263

  17. The Relation between Navigation Strategy and Associative Memory: An Individual Differences Approach

    Science.gov (United States)

    Ngo, Chi T.; Weisberg, Steven M.; Newcombe, Nora S.; Olson, Ingrid R.

    2016-01-01

    Although the hippocampus is implicated in both spatial navigation and associative memory, very little is known about whether individual differences in the 2 domains covary. People who prefer to navigate using a hippocampal-dependent place strategy may show better performance on associative memory tasks than those who prefer a caudate-dependent…

  18. Individual Differences in Working Memory Capacity Predict Sleep-Dependent Memory Consolidation

    Science.gov (United States)

    Fenn, Kimberly M.; Hambrick, David Z.

    2012-01-01

    Decades of research have established that "online" cognitive processes, which operate during conscious encoding and retrieval of information, contribute substantially to individual differences in memory. Furthermore, it is widely accepted that "offline" processes during sleep also contribute to memory performance. However, the question of whether…

  19. Different Perspectives: Spatial Ability Influences Where Individuals Look on a Timed Spatial Test

    Science.gov (United States)

    Roach, Victoria A.; Fraser, Graham M.; Kryklywy, James H.; Mitchell, Derek G. V.; Wilson, Timothy D.

    2017-01-01

    Learning in anatomy can be both spatially and visually complex. Pedagogical investigations have begun exploration as to how spatial ability may mitigate learning. Emerging hypotheses suggests individuals with higher spatial reasoning may attend to images differently than those who are lacking. To elucidate attentional patterns associated with…

  20. Developing teacher sensitivity to individual learning differences (ILDs) : Studies on increasing teacher effectiveness

    NARCIS (Netherlands)

    Rosenfeld, M.N.

    2008-01-01

    Effective teachers are sensitive to individual learning differences (ILDs). This dissertation investigates teacher changes as a result of eight long-term professional development (PD) courses (56-hours and 28-hours) designed to help them become more sensitive to ILDs. In these courses, the

  1. Unity and Diversity of Executive Functions: Individual Differences as a Window on Cognitive Structure

    Science.gov (United States)

    Friedman, Naomi P.; Miyake, Akira

    2016-01-01

    Executive functions (EFs) are high-level cognitive processes, often associated with the frontal lobes, that control lower level processes in the service of goal-directed behavior. They include abilities such as response inhibition, interference control, working memory updating, and set shifting. EFs show a general pattern of shared but distinct functions, a pattern described as “unity and diversity.” We review studies of EF unity and diversity at the behavioral and genetic levels, focusing on studies of normal individual differences and what they reveal about the functional organization of these cognitive abilities. In particular, we review evidence that across multiple ages and populations, commonly studied EFs (a) are robustly correlated but separable when measured with latent variables; (b) are not the same as general intelligence or g; (c) are highly heritable at the latent level and seemingly also highly polygenic; and (d) activate both common and specific neural areas and can be linked to individual differences in neural activation, volume, and connectivity. We highlight how considering individual differences at the behavioral and neural levels can add considerable insight to the investigation of the functional organization of the brain, and conclude with some key points about individual differences to consider when interpreting neuropsychological patterns of dissociation. PMID:27251123

  2. Age Differences within Secular IQ Trends: An Individual Growth Modeling Approach

    Science.gov (United States)

    Kanaya, Tomoe; Ceci, Stephen J.; Scullin, Matthew H.

    2005-01-01

    Age differences within the yo-yo trend in IQ, caused when aging norms that produce inflated scores are replaced with new norms, were examined using longitudinal WISC, WISC-R and WISC-III records of students tested for special education services from 10 school districts. Descriptive and individual growth modeling analyses revealed that while the…

  3. Individual Differences in the Post-Illumination Pupil Response to Blue Light : Assessment without Mydriatics

    NARCIS (Netherlands)

    Bruijel, Jessica; van der Meijden, Wisse P; Bijlenga, Denise; Dorani, Farangis; Coppens, Joris E; Te Lindert, Bart H W; Kooij, J J Sandra; Van Someren, Eus J W

    Melanopsin-containing retinal ganglion cells play an important role in the non-image forming effects of light, through their direct projections on brain circuits involved in circadian rhythms, mood and alertness. Individual differences in the functionality of the melanopsin-signaling circuitry can

  4. Variability in Second Language Learning: The Roles of Individual Differences, Learning Conditions, and Linguistic Complexity

    Science.gov (United States)

    Tagarelli, Kaitlyn M.; Ruiz, Simón; Vega, José Luis Moreno; Rebuschat, Patrick

    2016-01-01

    Second language learning outcomes are highly variable, due to a variety of factors, including individual differences, exposure conditions, and linguistic complexity. However, exactly how these factors interact to influence language learning is unknown. This article examines the relationship between these three variables in language learners.…

  5. Beyond Individual Differences: Exploring School Effects on SAT® Scores. Research Report No. 2004-3

    Science.gov (United States)

    Everson, Howard T.; Millsap, Roger E.

    2004-01-01

    This paper explores the complex, hierarchical relationship among school characteristics, individual differences in academic achievement, extracurricular activities, and socioeconomic background on performance on the SAT Reasoning Test™ verbal and mathematical sections. Using multilevel structural equation models (SEMs) with latent means, data from…

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

    Science.gov (United States)

    Fayn, Kirill; Kuppens, Peter

    2017-01-01

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

  7. Individual differences in decision making competence revealed by multivariate fMRI.

    Science.gov (United States)

    Talukdar, Tanveer; Román, Francisco J; Operskalski, Joachim T; Zwilling, Christopher E; Barbey, Aron K

    2018-03-08

    While an extensive literature in decision neuroscience has elucidated the neurobiological foundations of decision making, prior research has focused primarily on group-level effects in a sample population. Due to the presence of inherent differences between individuals' cognitive abilities, it is also important to examine the neural correlates of decision making that explain interindividual variability in cognitive performance. This study therefore investigated how individual differences in decision making competence, as measured by the Adult Decision Making Competence (A-DMC) battery, are related to functional brain connectivity patterns derived from resting-state fMRI data in a sample of 304 healthy participants. We examined connectome-wide associations, identifying regions within frontal, parietal, temporal, and occipital cortex that demonstrated significant associations with decision making competence. We then assessed whether the functional interactions between brain regions sensitive to decision making competence and seven intrinsic connectivity networks (ICNs) were predictive of specific facets of decision making assessed by subtests of the A-DMC battery. Our findings suggest that individual differences in specific facets of decision making competence are mediated by ICNs that support executive, social, and perceptual processes, and motivate an integrative framework for understanding the neural basis of individual differences in decision making competence. © 2018 Wiley Periodicals, Inc.

  8. Evolution, Convolution, Dissolution: The Rise of Individual Differences in Human Developmental Psychology.

    Science.gov (United States)

    Rickman, David L.

    Although it is difficult to ascertain precisely the time at which the study of individual differences became recognized as a specialty within the psychological sciences, there appears to be much agreement among historians that its development was fostered primarily within the United States during the late 19th century. This paper examines the…

  9. Comparing Different Classes of Reinforcement to Increase Expressive Language for Individuals with Autism

    Science.gov (United States)

    Leaf, Justin B.; Dale, Stephanie; Kassardjian, Alyne; Tsuji, Kathleen H.; Taubman, Mitchell; McEachin, John J.; Leaf, Ronald B.; Oppenheim-Leaf, Misty L.

    2014-01-01

    One of the basic principles of applied behavior analysis is that behavior change is largely due to that behavior being reinforced. Therefore the use of positive reinforcement is a key component of most behavioral programs for individuals diagnosed with autism. In this study we compared four different classes of reinforcers (i.e., food, praise,…

  10. Individual Differences in the Relationship between Satisfaction with Job Rewards and Job Satisfaction

    Science.gov (United States)

    Hofmans, Joeri; De Gieter, Sara; Pepermans, Roland

    2013-01-01

    Although previous research often showed a positive relationship between pay satisfaction and job satisfaction, we dispute the universality of this finding. Cluster-wise regression analyses on three samples consistently show that two types of individuals can be distinguished, each with a different job reward-job satisfaction relationship. For the…

  11. The Onion Model: Myth or Reality in the Field of Individual Differences Psychology?

    Science.gov (United States)

    Cools, Eva; Bellens, Kim

    2012-01-01

    To bring order in concepts related to individual learner differences, Curry (1983) designed the three-layered onion model. As this model provides an interesting way to distinguish related concepts--such as cognitive styles and approaches to studying--on the basis of their stability in learning situations, ample studies build further on this model.…

  12. 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

  13. Individual Differences in the Expression of Conditioned Fear Are Associated with Endogenous Fibroblast Growth Factor 2

    Science.gov (United States)

    Graham, Bronwyn M.; Richardson, Rick

    2016-01-01

    These experiments examined the relationship between the neurotrophic factor fibroblast growth factor 2 (FGF2) and individual differences in the expression of conditioned fear. Experiments 1 and 2 demonstrated that rats naturally expressing low levels of contextual or cued fear have higher levels of hippocampal FGF2 relative to rats that express…

  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. 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

  16. Fight or freeze? Individual differences in investors' motivational systems and trading in experimental asset markets

    NARCIS (Netherlands)

    Mühlfeld, K.; Weitzel, U.; van Witteloostuijn, A.

    2013-01-01

    We analyze investors’ trading behavior, particularly their coping with fundamental shocks in asset value, depending on individual differences in the sensitivity of two basic neurophysiological systems—the Behavioral Approach System (BAS), the ‘driving force’ of human behavior, and the Behavioral

  17. Genetic and Environmental Influences on Individual Differences in Sedentary Behavior During Adolescence

    NARCIS (Netherlands)

    van der Aa, N.; Bartels, M.; te Velde, S.J.; Boomsma, D.I.; de Geus, E.J.C.; Brug, J.

    2012-01-01

    Objective: To investigate the degree to which genetic and environmental influences affect individual differences in sedentary behavior throughout adolescence. Design: Cross-sectional twin-family design. Setting: Data on self-reported sedentary behavior from Dutch twins and their nontwin siblings.

  18. Training Participation and Gender: Analyzing Individual Barriers across Different Welfare State Regimes

    Science.gov (United States)

    Massing, Natascha; Gauly, Britta

    2017-01-01

    Lifelong learning is becoming increasingly important in today's societies. Individuals need to develop their skills through training in order to be successfully integrated in the labor market. We use data from the Programme for the International Assessment of Adult Competencies to investigate gender differences in training across 12 countries. We…

  19. Similarities and differences in dream content at the cross-cultural, gender, and individual levels.

    Science.gov (United States)

    William Domhoff, G; Schneider, Adam

    2008-12-01

    The similarities and differences in dream content at the cross-cultural, gender, and individual levels provide one starting point for carrying out studies that attempt to discover correspondences between dream content and various types of waking cognition. Hobson and Kahn's (Hobson, J. A., & Kahn, D. (2007). Dream content: Individual and generic aspects. Consciousness and Cognition, 16, 850-858.) conclusion that dream content may be more generic than most researchers realize, and that individual differences are less salient than usually thought, provides the occasion for a review of findings based on the Hall and Van de Castle (Hall, C., & Van de Castle, R. (1966). The content analysis of dreams. New York: Appleton-Century-Crofts.) coding system for the study of dream content. Then new findings based on a computationally intensive randomization strategy are presented to show the minimum sample sizes needed to detect gender and individual differences in dream content. Generally speaking, sample sizes of 100-125 dream reports are needed because most dream elements appear in less than 50% of dream reports and the magnitude of the differences usually is not large.

  20. Effects of Situated Learning on Students' Knowledge Acquisition: An Individual Differences Perspective

    Science.gov (United States)

    Zheng, Robert

    2010-01-01

    This study focuses on the effects of situated learning on students' knowledge acquisition by investigating the influence of individual differences in such learning. Seventy-nine graduates were recruited from an educational department and were assigned to situated learning and traditional learning based on a randomized block design. Results…

  1. Population biology of intestinal Enterococcus Isolates from hospitalized and nonhospitalized individuals in different age groups

    NARCIS (Netherlands)

    Tedim, Ana P.; Ruiz-Garbajosa, Patricia; Corander, Jukka; Rodríguez, Concepción M.; Cantón, Rafael; Willems, Rob J.; Baquero, Fernando; Coque, Teresa M.

    2015-01-01

    The diversity of enterococcal populations from fecal samples from hospitalized (n=133) and nonhospitalized individuals (n= 173) of different age groups (group I, ages 0 to 19 years; group II, ages 20 to 59 years; group III, ages≥60 years) was analyzed. Enterococci were recovered at similar rates

  2. A Standardized Mean Difference Effect Size for Multiple Baseline Designs across Individuals

    Science.gov (United States)

    Hedges, Larry V.; Pustejovsky, James E.; Shadish, William R.

    2013-01-01

    Single-case designs are a class of research methods for evaluating treatment effects by measuring outcomes repeatedly over time while systematically introducing different condition (e.g., treatment and control) to the same individual. The designs are used across fields such as behavior analysis, clinical psychology, special education, and…

  3. Individual differences in the use of social information in foraging by captive great tits

    NARCIS (Netherlands)

    Marchetti, C.M.; Drent, P.J.

    2000-01-01

    We investigated individual differences in copying behaviour of captive great tits, Parus major, by analysing their response to a tutor indicating a new feeding site. We used two groups, each di seven male birds, labelled 'fast' and 'slow' explorers based on previous studies in which consistent

  4. Individual differences on social comparison : properties of the orientation Spanish scale towards social comparison

    NARCIS (Netherlands)

    Buunk, AP; Belmonte, J; Peiro, JM; Zurriaga, R; Gibbons, FX

    2005-01-01

    This paper describes the development and the properties of the INCOM-E, the Spanish language version of the INCOM, a measure to assess individual differences in social comparison orientation that was originally developed simultaneously in English and in Dutch. In both Study 1 (including 212

  5. Comparison of craving for opioid in opioid-dependent individuals and people under methadone maintenance treatment

    Directory of Open Access Journals (Sweden)

    Azita Chehri

    2014-02-01

    Full Text Available Background: Methadone Maintenance Therapy (MMT is the most important treatment for opioid -dependency recurrence. The aim of this study was to compare the craving level in opioid-dependent individuals and people under methadone maintenance therapy. Methods: In this case – control study, 120 men with opioid dependency were selected through cluster sampling method. They were divided into two groups, 60 people in opioid-dependent group and 60 people in MMT group. Both groups were matched for age, sex, marital status, education, duration of opioid dependency and method of consumption. Then, they completed INCAS Substance Abuse Profile (ISAP, opiate withdrawal symptoms checklist, self–report of craving, Desire for Drug Questionnaire (DDQ, Obsessive Compulsive Drug Use Scale (OCDUS and visual cue-induced craving questionnaire. Data were analyzed by SPSS 15 using t-test and ANOVA. Results: Mean craving for drug significantly was lower in MMT group comparing opioid-dependent group (P<0.01. Conclusion: Methadone Maintenance Therapy decreased the craving for drugs and substances This can have an important role in relapse prevention.

  6. Gender Identity and Adjustment: Understanding the Impact of Individual and Normative Differences in Sex Typing

    Science.gov (United States)

    Lurye, Leah E.; Zosuls, Kristina M.; Ruble, Diane N.

    2009-01-01

    The relationship among gender identity, sex typing, and adjustment has attracted the attention of social and developmental psychologists for many years. However, they have explored this issue with different assumptions and different approaches. Generally the approaches differ regarding whether sex typing is considered adaptive versus maladaptive, measured as an individual or normative difference, and whether gender identity is regarded as a unidimensional or multidimensional construct. In this chapter, we consider both perspectives and suggest that the developmental timing and degree of sex typing, as well as the multidimensionality of gender identity, be considered when examining their relationship to adjustment. PMID:18521861

  7. Gender identity and adjustment: understanding the impact of individual and normative differences in sex typing.

    Science.gov (United States)

    Lurye, Leah E; Zosuls, Kristina M; Ruble, Diane N

    2008-01-01

    The relationship among gender identity, sex typing, and adjustment has attracted the attention of social and developmental psychologists for many years. However, they have explored this issue with different assumptions and different approaches. Generally the approaches differ regarding whether sex typing is considered adaptive versus maladaptive, measured as an individual or normative difference, and whether gender identity is regarded as a unidimensional or multidimensional construct. In this chapter, we consider both perspectives and suggest that the developmental timing and degree of sex typing, as well as the multidimensionality of gender identity, be considered when examining their relationship to adjustment.

  8. Experimental study of infrared filaments under different initial conditions

    Science.gov (United States)

    Mirell, Daniel Joseph

    field that gives birth to multiphoton and avalanche ionization), (b) conical emission/supercontinuum generation, and (c) emitted THz radiation. The aim of all of this research is to gain a better understanding of filamentation so that we may learn how to control them for the applications of: (a) laser-induced lightning, (b) laser-induced breakdown spectroscopy, (c) LIDAR, (d) medical imaging and many more. In this dissertation we will focus on an experimental study of filamentation in air produced by 780 nm radiation, pulsewidths of 200 fs, and energies pulse of 9 mJ/pulse. We have used an aerodynamic window + vacuum system to study the difference between focusing filament forming pulses down initially in vacuum conditions to that where it is allowed to focus in atmosphere. Described herein is a new way to use an off-the-shelf, inexpensive and robust 1064 nm mirror to observe the beam profile and its evolution in the filament as well as the filaments spectral properties. In addition, experiments to test for the plasma have been conducted. The results of these experiments indicate filament sizes of 200mum, in contrast to the commonly reported value of 100pm. Filaments of this size exist over a length of approximately a meter which is 8 times longer than the associated Rayleigh range for such a spot size with a clear enhancement in filament persistence with the use of the aerodynamic window. In addition the appearance of newly generated "bluer" frequencies that is present under atmospheric focusing is ail but eliminated through an initial focusing of the beam in vacuum conditions. Plasma densities of 1016 e -/cm3 were measured using plasma interferometry.

  9. An Individual Differences Approach to Temporal Integration and Order Reversals in the Attentional Blink Task.

    Science.gov (United States)

    Willems, Charlotte; Saija, Jefta D; Akyürek, Elkan G; Martens, Sander

    2016-01-01

    The reduced ability to identify a second target when it is presented in close temporal succession of a first target is called the attentional blink (AB). Studies have shown large individual differences in AB task performance, where lower task performance has been associated with more reversed order reports of both targets if these were presented in direct succession. In order to study the suggestion that reversed order reports reflect loss of temporal information, in the current study, we investigated whether individuals with a larger AB have a higher tendency to temporally integrate both targets into one visual event by using an AB paradigm containing symbol target stimuli. Indeed, we found a positive relation between the tendency to temporally integrate information and individual AB magnitude. In contrast to earlier work, we found no relation between order reversals and individual AB magnitude. The occurrence of temporal integration was negatively related to the number of order reversals, indicating that individuals either integrated or separated and reversed information. We conclude that individuals with better AB task performance use a shorter time window to integrate information, and therefore have higher preservation of temporal information. Furthermore, order reversals observed in paradigms with alphanumeric targets indeed seem to at least partially reflect temporal integration of both targets. Given the negative relation between temporal integration and 'true' order reversals observed with the current symbolic target set, these two behavioral outcomes seem to be two sides of the same coin.

  10. An Individual Differences Approach to Temporal Integration and Order Reversals in the Attentional Blink Task.

    Directory of Open Access Journals (Sweden)

    Charlotte Willems

    Full Text Available The reduced ability to identify a second target when it is presented in close temporal succession of a first target is called the attentional blink (AB. Studies have shown large individual differences in AB task performance, where lower task performance has been associated with more reversed order reports of both targets if these were presented in direct succession. In order to study the suggestion that reversed order reports reflect loss of temporal information, in the current study, we investigated whether individuals with a larger AB have a higher tendency to temporally integrate both targets into one visual event by using an AB paradigm containing symbol target stimuli.Indeed, we found a positive relation between the tendency to temporally integrate information and individual AB magnitude. In contrast to earlier work, we found no relation between order reversals and individual AB magnitude. The occurrence of temporal integration was negatively related to the number of order reversals, indicating that individuals either integrated or separated and reversed information.We conclude that individuals with better AB task performance use a shorter time window to integrate information, and therefore have higher preservation of temporal information. Furthermore, order reversals observed in paradigms with alphanumeric targets indeed seem to at least partially reflect temporal integration of both targets. Given the negative relation between temporal integration and 'true' order reversals observed with the current symbolic target set, these two behavioral outcomes seem to be two sides of the same coin.

  11. Speech fluency profile on different tasks for individuals with Parkinson's disease.

    Science.gov (United States)

    Juste, Fabiola Staróbole; Andrade, Claudia Regina Furquim de

    2017-07-20

    To characterize the speech fluency profile of patients with Parkinson's disease. Study participants were 40 individuals of both genders aged 40 to 80 years divided into 2 groups: Research Group - RG (20 individuals with diagnosis of Parkinson's disease) and Control Group - CG (20 individuals with no communication or neurological disorders). For all of the participants, three speech samples involving different tasks were collected: monologue, individual reading, and automatic speech. The RG presented a significant larger number of speech disruptions, both stuttering-like and typical dysfluencies, and higher percentage of speech discontinuity in the monologue and individual reading tasks compared with the CG. Both groups presented reduced number of speech disruptions (stuttering-like and typical dysfluencies) in the automatic speech task; the groups presented similar performance in this task. Regarding speech rate, individuals in the RG presented lower number of words and syllables per minute compared with those in the CG in all speech tasks. Participants of the RG presented altered parameters of speech fluency compared with those of the CG; however, this change in fluency cannot be considered a stuttering disorder.

  12. 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.

  13. 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.

  14. 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

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

    Science.gov (United States)

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

    2011-09-01

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

  16. MODELING OF THE BEHAVIOUR REOLOGICHESKIH TEL UNDER DIFFERENT LAW NAGRUZHENIYA

    Directory of Open Access Journals (Sweden)

    V. V. Bendyukov

    2014-01-01

    Full Text Available The Offered model of the behaviour reologicheskogo bodies (the viscous-elasticity of the materia, designs or systems under controlling influence of the load, acting on given law for some time.

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

    Science.gov (United States)

    Park, Seongmin A; Goïame, Sidney; O'Connor, David A; Dreher, Jean-Claude

    2017-06-01

    When making judgments in a group, individuals often revise their initial beliefs about the best judgment to make given what others believe. Despite the ubiquity of this phenomenon, we know little about how the brain updates beliefs when integrating personal judgments (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. By testing different theoretical models, we showed that a social Bayesian inference model captured changes in judgments better than 2 other models. Our results showed that participants updated their beliefs by appropriately weighting individual and social sources of information according to their respective credibility. When investigating 2 fundamental computations of Bayesian inference, belief updates and credibility estimates of social information, we found that the dorsal anterior cingulate cortex (dACC) computed the level of belief updates, while the bilateral frontopolar cortex (FPC) was more engaged in individuals who assigned a greater credibility to the judgments of a larger group. Moreover, increased functional connectivity between these 2 brain regions reflected a greater influence of group size on the relative credibility of social information. These results provide a mechanistic understanding of the computational roles of the FPC-dACC network in steering judgment adaptation to a group's opinion. Taken together, these findings provide a computational account of how the human brain integrates individual and social information for decision-making in groups.

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

    Directory of Open Access Journals (Sweden)

    Seongmin A Park

    2017-06-01

    Full Text Available When making judgments in a group, individuals often revise their initial beliefs about the best judgment to make given what others believe. Despite the ubiquity of this phenomenon, we know little about how the brain updates beliefs when integrating personal judgments (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. By testing different theoretical models, we showed that a social Bayesian inference model captured changes in judgments better than 2 other models. Our results showed that participants updated their beliefs by appropriately weighting individual and social sources of information according to their respective credibility. When investigating 2 fundamental computations of Bayesian inference, belief updates and credibility estimates of social information, we found that the dorsal anterior cingulate cortex (dACC computed the level of belief updates, while the bilateral frontopolar cortex (FPC was more engaged in individuals who assigned a greater credibility to the judgments of a larger group. Moreover, increased functional connectivity between these 2 brain regions reflected a greater influence of group size on the relative credibility of social information. These results provide a mechanistic understanding of the computational roles of the FPC-dACC network in steering judgment adaptation to a group's opinion. Taken together, these findings provide a computational account of how the human brain integrates individual and social information for decision-making in groups.

  19. Revisiting the impact of job satisfaction and organizational commitment on nurse turnover intention: an individual differences analysis.

    Science.gov (United States)

    De Gieter, Sara; Hofmans, Joeri; Pepermans, Roland

    2011-12-01

    of the underlying individual differences in nurse turnover antecedents. 2011 Elsevier Ltd. All rights reserved.

  20. Biodegradation of NSO-compounds under different redox-conditions

    DEFF Research Database (Denmark)

    Dyreborg, S.; Arvin, E.; Broholm, K.

    1997-01-01

    Laboratory experiments were carried out to investigate the potential of groundwater microorganisms to degrade selected heterocyclic aromatic compounds containing nitrogen, sulphur, or oxygen (NSO-compounds) under four redox-conditions over a period of 846 days. Eight compounds (pyrrole, 1-methylp...... together with the long lag periods and the low degradation rates under aerobic conditions suggest that NSO-compounds might persist in groundwater at creosote-contaminated sites. (C) 1997 Elsevier Science B.V....