Sandlund, Jonas; Srinivasan, Divya; Heiden, Marina; Mathiassen, Svend Erik
Motor variability (MV) has been suggested to be a determinant of the risk for developing musculoskeletal disorders in repetitive work. In this study we examined whether individuals consistently differed in the extent of motor variability when performing a standardized short-cycle manual task. On three separate days, arm kinematics was recorded in 14 healthy subjects performing a pipetting task, transferring liquid from a pick-up tube to eight target tubes with a cycle time of 2.8s. Cycle-to-cycle standard deviations (SD) of a large selection of shoulder and elbow kinematic variables, were processed using principal component analysis (PCA). Thereafter, between-subjects and between-days (within-subject) variance components were calculated using a random effects model for each of four extracted principal components. The results showed that MV differed consistently between subjects (95% confidence intervals of the between-subjects variances did not include zero) and that subjects differed consistently in MV between days. Thus, our results support the notion that MV may be a consistent personal trait, even though further research is needed to verify whether individuals rank consistently in MV even across tasks. If so, MV may be a candidate determinant of the risk of developing fatigue and musculoskeletal disorders in repetitive occupational work.
Hedges, Larry V.; Pustejovsky, James E.; Shadish, William R.
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…
Singer, Sandra M.
These demonstrations stress individual differences, a concept becoming increasingly important in psychological research. Intended for use in undergraduate psychology courses, four demonstrations that illustrate common examples of human variation are described. The demonstrations deal with the following individual differences: taste blindness,…
Cavalier, Albert R.; And Others
Six papers on special education technology and individual differences are introduced. The papers illustrate the growing influence of constructivist perspectives on the use of technology to accommodate individual differences among people. The papers recognize the importance of using technology to scaffold the client's construction of different…
This document contains four papers from a symposium on individual differences in learning. "Novice and Expert Learning: Impact on Training" (Barbara J. Daley) reports on a study in which 20 novice and expert nurses were interviewed to identify their different learning processes and the factors that facilitated or hindered their learning.…
The activities of an Italian operating group for the standardization of individual dosimeters are discussed. Intercalibration was performed for about 10,000 individual dosimeters in order to analyze systematic and random measuring errors. The validity of normalized inspection procedures was examined and the necessity of periodic checks was considered. Legislation is proposed including a technical inspection prior to authorization to start a dosimetry center and a norm for periodic controls of dosimetry services. The creation of a dosimetric data bank is also suggested.
This paper argues that infants' affect patterns are innate and are meaningful indicators of individual differences in internal state. Videotapes of seven infants' faces were coded using an ethogram; the movement of the eyebrow, eye direction, eye openness, mouth shape, mouth position, lip position, and tongue protrusion were assessed…
Villalta-Gil, Victoria; Hinton, Kendra E; Landman, Bennett A; Yvernault, Benjamin C; Perkins, Scott F; Katsantonis, Allison S; Sellani, Courtney L; Lahey, Benjamin B; Zald, David H
The amygdala (AMG) has been repeatedly implicated in the processing of threatening and negatively valenced stimuli and multiple fMRI paradigms have reported personality, genetic, and psychopathological associations with individual differences in AMG activation in these paradigms. Yet the interchangeability of activations in these probes has not been established, thus it remains unclear if we can interpret AMG responses on specific tasks as general markers of its reactivity. In this study we aimed to assess if different tasks that have been widely used within the Affective Neuroscience literature consistently recruit the AMG.
Gur, Ruben C; Richard, Jan; Hughett, Paul; Calkins, Monica E; Macy, Larry; Bilker, Warren B; Brensinger, Colleen; Gur, Raquel E
There is increased need for efficient computerized methods to collect reliable data on a range of cognitive domains that can be linked to specific brain systems. Such need arises in functional neuroimaging studies, where individual differences in cognitive performance are variables of interest or serve as confounds. In genetic studies of complex behavior, which require particularly large samples, such trait measures can serve as endophenotypes. Traditional neuropsychological tests, based on clinical pathological correlations, are protracted, require extensive training in administration and scoring, and leave lengthy paper trails (double-entry for analysis). We present a computerized battery that takes an average of 1h and provides measures of accuracy and speed on 9 neurocognitive domains. They are cognitive neuroscience-based in that they have been linked experimentally to specific brain systems with functional neuroimaging studies. We describe the process of translating tasks used in functional neuroimaging to tests for assessing individual differences. Data are presented on each test with samples ranging from 139 (81 female) to 536 (311 female) of carefully screened healthy individuals ranging in age from 18 to 84. Item consistency was established with acceptable to high Cronbach alpha coefficients. Inter-item correlations were moderate to high within domain and low to nil across domains, indicating construct validity. Initial criterion validity was demonstrated by sensitivity to sex differences and the effects of age, education and parental education. These results encourage the use of this battery in studies needing an efficient assessment of major neurocognitive domains such as multi-site genetic studies and clinical trials.
In the present paper, we (1) study whether people differ in the equity models they use, and (2) test whether individual differences in equity models relate to individual differences in equity sensitivity. To achieve this goal, an Information Integration experiment was performed in which participants were given information on the performance of two…
Ayersman, David J.; Minden, Avril von
Provides a conceptual foundation for the development of hypermedia as an instructional tool for addressing individual differences in learning styles. Highlights include a literature review; computers and instruction; individual differences, computers, and instruction; cognitive controls; cognitive styles and learning; personality types; and future…
Arabski, Janusz; Wojtaszek, Adam
"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?
Powell, Georgie; Meredith, Zoe; McMillin, Rebecca; Freeman, Tom C. A.
According to Bayesian models, perception and cognition depend on the optimal combination of noisy incoming evidence with prior knowledge of the world. Individual differences in perception should therefore be jointly determined by a person’s sensitivity to incoming evidence and his or her prior expectations. It has been proposed that individuals with autism have flatter prior distributions than do nonautistic individuals, which suggests that prior variance is linked to the degree of autistic traits in the general population. We tested this idea by studying how perceived speed changes during pursuit eye movement and at low contrast. We found that individual differences in these two motion phenomena were predicted by differences in thresholds and autistic traits when combined in a quantitative Bayesian model. Our findings therefore support the flatter-prior hypothesis and suggest that individual differences in prior expectations are more systematic than previously thought. In order to be revealed, however, individual differences in sensitivity must also be taken into account. PMID:27770059
Jackson, Russell E
Distance perception is among the most pervasive mental phenomena and the oldest research topics in behavioural science. However, we do not understand well the most pervasive finding of distance perception research, that of large individual differences. There are large individual differences in acrophobia (fear of heights), which we commonly assume consists of an abnormal fear of stimuli perceived normally. Evolved navigation theory (ENT) instead suggests that acrophobia consists of a more normal fear of stimuli perceived abnormally. ENT suggests that distance perception individual differences produce major components of acrophobia. Acrophobia tested over a broad range in the present study predicted large individual differences in distance estimation of surfaces that could produce falls. This fear of heights correlated positively with distance estimates of a vertical surface-even among non-acrophobic individuals at no risk of falling and without knowledge of being tested for acrophobia. Acrophobia score predicted magnitude of the descent illusion, which is thought to reflect the risk of falling. These data hold important implications in environmental navigation, clinical aetiology and the evolution of visual systems.
Joint Commission on Accreditation of Hospitals, Chicago, IL.
Provided are standards for agencies and hospitals serving developmentally disabled persons with emphasis on planning and implementing individual programs. The introduction provides information on the establishment of the Accreditation Council for Services for Mentally Retarded and Other Developmentally Disabled Persons and the Joint Commission on…
Sanders, Perry R.; Conti, Gary J.
Although One-Stop Career Centers are mandated to promote client-centered services, patrons are ordinarily funneled through a standard procedure. Adult education principles suggest that these centers should be learner-centered and address individual differences. Therefore, the purpose of the this study was to describe the interaction of the…
Aphasia affecting the cerebral nemisphere on the same side as the preferred hand has also long been understood. Individual variation in degree...no LVF superiority for recognising dot patterns (Harcum and Dyer, 1962) and no differences between sides to a unilateral auditory stimulus...equal frequency after either left or right sides lesions, sinistrals with only dextral relatives tended to develop aphasia after only left sided
Dawis, Rene V.
Traces historical development from individual differences psychology through psychological testing, vocational counseling, and student personnel work, to counseling psychology. Describes individual differences tradition in counseling psychology research and practice. Discusses how individual differences psychology has influenced counseling…
Geary, D C; Widaman, K F
Relations factor was found. Results of the structural modeling support the conclusion that information retrieval from a network of arithmetic facts and execution of the carry operation are elementary component processes involved uniquely in the mental solving of arithmetic problems. Furthermore, individual differences in the speed of executing these two elementary component processes appear to underlie individual differences on ability measures that traditionally span the Numerical Facility factor.(ABSTRACT TRUNCATED AT 400 WORDS)
Fasko, Daniel, Jr.
Recent educational research indicates that learners differ in their preferences for learning mode and strategies. Implications for instruction and assessment are discussed as they relate to the Theory of Multiple Intelligences of H. Gardner (1983). One of the principles of the "Learner Centered Psychological Principles" of the American…
Reports that, even though young infants can discriminate among different facial expressions, there are individual differences in infants' expressivity and ability to produce and discriminate facial expressions. (PCB)
Williams, Ben; Myerson, Joel; Hale, Sandra
Despite its avowed goal of understanding individual behavior, the field of behavior analysis has largely ignored the determinants of consistent differences in level of performance among individuals. The present article discusses major findings in the study of individual differences in intelligence from the conceptual framework of a functional…
Belmaker, Rh; Bersudsky, Yuly; Agam, Galila
Individual differences in response to pharmacologic treatment limits the usefulness of mean data obtained from randomized controlled trials. These individual differences exist even in genetically uniform inbred mouse strains. While stratification can be of value in large studies, the individual patient history is the most effective currently available guide for personalized medicine in psychopharmacology.
Lucon-Xiccato, Tyrone; Bisazza, Angelo
Individual differences in cognitive abilities have been thoroughly investigated in humans and to a lesser extent in other mammals. Despite the growing interest in studying cognition in other taxonomic groups, data on individual differences are scarce for non-mammalian species. Here, we review the literature on individual differences in cognitive abilities in teleost fishes. Relatively few studies have directly addressed this topic and have provided evidence of consistent and heritable individual variation in cognitive abilities in fish. We found much more evidence of individual cognitive differences in other research areas, namely sex differences, personality differences, cerebral lateralisation and comparison between populations. Altogether, these studies suggest that individual differences in cognition are as common in fish as in warm-blooded vertebrates. Based on the example of research on mammals, we suggest directions for future investigation in fish.
Seegmiller, Janelle K.; Watson, Jason M.; Strayer, David L.
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…
Wilkinson, R. T.
The literature on the effects of noise on sleep is searched for evidence on individual differences along the dimensions of age, sex, occupation, personality, neuroticism, and mental health. With the exception of age, little firm evidence is found. Thus there remains a need to establish at better than the anecdotal level whether or not real individual differences exist.
Senner, Nathan R.; Conklin, Jesse R.; Piersma, Theunis
Phenotypic differences among individuals can arise during any stage of life. Although several distinct processes underlying individual differences have been defined and studied (e.g. parental effects, senescence), we lack an explicit, unified perspective for understanding how these processes contribute separately and synergistically to observed variation in functional traits. We propose a conceptual framework based on a developmental view of life-history variation, linking each ontogenetic stage with the types of individual differences originating during that period. In our view, the salient differences among these types are encapsulated by three key criteria: timing of onset, when fitness consequences are realized, and potential for reversibility. To fill a critical gap in this framework, we formulate a new term to refer to individual differences generated during adulthood—reversible state effects. We define these as ‘reversible changes in a functional trait resulting from life-history trade-offs during adulthood that affect fitness’, highlighting how the adult phenotype can be repeatedly altered in response to environmental variation. Defining individual differences in terms of trade-offs allows explicit predictions regarding when and where fitness consequences should be expected. Moreover, viewing individual differences in a developmental context highlights how different processes can work in concert to shape phenotype and fitness, and lays a foundation for research linking individual differences to ecological and evolutionary theory. PMID:26336173
Dall, Sasha R. X.; Bell, Alison M.; Bolnick, Daniel I.; Ratnieks, Francis L. W.
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
Neel, Rebecca; Kenrick, Douglas T; White, Andrew Edward; Neuberg, Steven L
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
Leclerc, Martin; Vander Wal, Eric; Zedrosser, Andreas; Swenson, Jon E; Kindberg, Jonas; Pelletier, Fanie
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.
... Emissions From Petroleum Refinery Wastewater Systems § 60.692-2 Standards: Individual drain systems. (a)(1... section. (e) Refinery wastewater routed through new process drains and a new first common...
... Emissions From Petroleum Refinery Wastewater Systems § 60.692-2 Standards: Individual drain systems. (a)(1... section. (e) Refinery wastewater routed through new process drains and a new first common...
... Emissions From Petroleum Refinery Wastewater Systems § 60.692-2 Standards: Individual drain systems. (a)(1... section. (e) Refinery wastewater routed through new process drains and a new first common...
Modjeska, David; Chignell, Mark
Discussion of information visualization and computer graphics focuses on a study that contrasted performance in three dimensional (3D) and two dimensional zooming interactively (2.5D) virtual worlds for people with differing levels of spatial and structure learning ability. Suggests implications of individual differences for the usability and…
Voytchev, M; Ambrosi, P; Behrens, R; Chiaro, P
This paper presents IEC/SC 45B 'Radiation protection instrumentation' and its standards for individual monitoring of ionising radiation: IEC 61526 Ed. 3 for active personal dosemeters and IEC 62387-1 for passive integrating dosimetry systems. The transposition of these standards as CENELEC (European) standards is also discussed together with the collaboration between IEC/SC 45B and ISO/TC 85/SC 2.
Voytchev, Miroslav; Ambrosi, P.; Behrens, R.; Chiaro Jr, Peter John
This paper presents IEC/SC 45B Radiation protection instrumentation and its standards for individual monitoring of ionising radiation: IEC 61526 Ed. 3 for active personal dosemeters and IEC 62387-1 for passive integrating dosimetry systems. The transposition of these standards as CENELEC (European) standards is also discussed together with the collaboration between IEC/SC 45B and ISO/TC 85/SC 2.
Ide, Soichiro; Kasai, Shinya; Ikeda, Kazutaka
Narcotic analgesics have been widely used for management of severe pain, especially for cancer pain. Most of these drugs are opioids, and they show their analgesic effects by acting through opioid receptors. Significant individual differences in opioid sensitivity can hamper effective pain treatments and increase side effects, which is associated with decreased quality of life. It is thought that genetic factors may affect individual differences in opioid sensitivity. Recent studies using various inbred and knockout mice have revealed that the mu-opioid receptor (MOP) plays a mandatory role in the analgesic properties of opioids. There is also increasing evidence that differences in the sequence of the MOP gene might significantly affect the amount of MOP gene mRNA expression and sensitivity to opioids. Furthermore, it can be thought that individual differences in opioid sensitivity are caused by genetic differences in not only MOP but other biomolecules, such as endogenous opioid peptides, molecules related with metabolic process and second messenger systems. Rapid advances in this research field are leading to a better understanding of relationships between gene polymorphisms and opioid sensitivities, which, in turn, will allow us to more accurately predict opioid sensitivity and opioid requirements in individual patients.
Tenorio, Marcela; Campos, Ruth; Karmiloff-Smith, Annette
In this article we critique the use of traditional standardized tests for the cognitive assessment of children with neurodevelopmental disorders. Limitations stem from the lack of integrating (a) results from research into the psychological functioning of these populations, and (b) the main arguments underlying models of human development. We identify four secondary issues in this discussion: (1) these instruments cannot be used with children who have particularly low cognitive functioning; (2) little or no variance in the scores obtained by individuals with neurodevelopmental disorders, because all are at floor, prevent adequate interpretations; (3) measurements do not provide information useful for the design of intervention strategies; and (4) different cognitive and/or neural processes may underlie behavioural scores ‘in the normal range’. Rethinking traditional assessment methods in favour of technologically-mediated games yields new cognitive assessment possibilities. PMID:26778874
Jeffrey C. Joe; Ronald L. Boring
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.
Andersen, Barbara L.; Cyranowski, Jill M.
Discusses classic and contemporary approaches to the assessment of female sexuality. General approaches, assessment strategies, and models of female sexuality are organized within the conceptual domains of sexual behaviors, sexual responses, and individual differences, including general and sex-specific personality models. Highlights trends and…
Unsworth, Nash; McMillan, Brittany D.; Brewer, Gene A.; Spillers, Gregory J.
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…
Horn, Elizabeth M.; Collier, William G.; Oxford, Julie A.; Bond, Charles F., Jr.; Dansereau, Donald F.
The impact of individual differences on the performance of roles of learner and learning facilitator was studied during dyadic cooperative learning with 80 college students in same-sex groups of 4. The learner role accounted for more than 70% of the variance in total recall. The influence of cognitive and rapport factors is discussed. (SLD)
Samah, Norazrena Abu; Yahaya, Noraffandy; Ali, Mohamad Bilal
The need has arise for the consideration of individual differences, to include their learning styles, learning orientations, preferences and needs in learning to allow learners engage and be responsible for their own learning, retain information longer, apply the knowledge more effectively, have positive attitudes towards the subject, have more…
Geisler-Brenstein, E.; And Others
A study of 325 university students explored relationships between personality and learning styles in students with high or low self-esteem. Ways that personality and learning theory can combine to help define individual differences in learning, their origins, manifestation, and amenability to change are examined. Implications for achievement,…
Ever since the early days of its existence, the field of psychology has been trying to achieve two different and somewhat contradictory objectives: to understand the "general principles" of the human mind and to explore the "uniqueness" of the individual mind. The latter direction has formed an independent subdiscipline within…
Ardila, Alfredo; Rosselli, Monica
It is proposed that depending upon the specific pattern of cognitive abilities, each individual lives in an idiosyncratic "cognitive world." Brain pathology can be associated with some disturbed abilities, and frequently experiential changes (i.e., how the world is understood) are observed. Because these patients often are aware of their intellectual changes, they may represent excellent models to illustrate the diversity of cognitive interpretations an individual can have about the surrounding environmental conditions. Four neuropsychology cases are presented to illustrate this point: (a) prosopagnosia associated with spatial agnosia; (b) Gerstmann's syndrome; (c) dysexecutive syndrome due to a head injury; and, (d) patient with Capgras' syndrome associated with a left temporal cyst. It is further emphasized that non-brain damaged people present an enormous-but usually overlooked-dispersion in different cognitive domains, resulting in specific and idiosyncratic patterns of cognitive abilities. It is concluded that the concept of "cognitive world" in neuropsychology can parallel the concept of "perceptual world" introduced by von Uexküll in biology, which assumes that different animal species live in idiosyncratic perceptual worlds, available and knowable by the differences in their sensory system abilities. That is, different individuals live in idiosyncratic cognitive worlds, owing to their differences in cognitive abilities.
Romeo, Marina; Yepes-Baldó, Montserrat; Berger, Rita; Netto Da Costa, Francisco Franco
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 mens 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.
Sbarra, David A.; Hasselmo, Karen; Bourassa, Kyle J.
This paper reviews what is known about the association between marital dissolution and health outcomes in adults. Two of the major empirical findings in the literature—that most people do well following marital separation and that this life event increases risk for poor outcomes—appear to be in contrast. This paper provides an individual differences framework for reconciling these competing perspectives and suggests that the bulk of the risk for poor outcomes following marital dissolution is carried by a minority of people. Research focusing on at-risk populations is beginning to shed light on mechanisms of action, the processes that explain why and how marital separation and divorce are associated with ill health. The paper outlines a series of future directions that go beyond individual differences to study these mechanisms. PMID:25892857
Keye, Doris; Wilhelm, Oliver; Oberauer, Klaus; Stürmer, Birgit
Conflict-monitoring theory argues for a general cognitive mechanism that monitors for conflicts in information-processing. If that mechanism detects conflict, it engages cognitive control to resolve it. A slow-down in response to incongruent trials (conflict effect), and a modulation of the conflict effect by the congruence of the preceding trial (Gratton or context effect) have been taken as indicators of such a monitoring system. The present study (N = 157) investigated individual differences in the conflict and the context effect in a horizontal and a vertical Simon task, and their correlation with working memory capacity (WMC). Strength of conflict was varied by proportion of congruent trials. Coherent factors could be formed representing individual differences in speeded performance, conflict adaptation, and context adaptation. Conflict and context factors were not associated with each other. Contrary to theories assuming a close relation between working memory and cognitive control, WMC showed no relation with any factors representing adaptation to conflict. PMID:24385971
Lee, Joanna C.; Tomblin, J. Bruce
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 system. The findings showed that variance in language abilities is associated with performance on different domains of procedural memory, including the motor domain (as shown in the pursuit rotor task), the cognitive domain (as shown in the weather prediction task), and the linguistic domain (as shown in the nonword repetition priming task). These results implicate the corticostriatal system in individual differences in language. PMID:26190949
Uttl, Bob; White, Carmela A; Wong Gonzalez, Daniela; McDouall, Joanna; Leonard, Carrie A
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.
Jung, Rex E; Ryman, Sephira G; Vakhtin, Andrei A; Carrasco, Jessica; Wertz, Chris; Flores, Ranee A
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).
Cacioppo et al., 1996) a tendency to look toward other for standards of behavior , rather than oneself (Crowley & Hoyer , 1989) and less ‘buck-passing...and competitive behavior in a group task. Academy of Management Journal, 34, 827-847. Crowley, A. E., & Hoyer , W. D. (1989). The relationship between...1989) has suggested, individual differences may affect behavior only when paired with situational conditions that induce stress (i. e., a stress
Schloss, Karen B; Hawthorne-Madell, Daniel; Palmer, Stephen E
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.
Hyvönen, H; Vartiainen, E
In this paper the implementation of a quality system to the procedures of an individual monitoring service (IMS) is described from the practical perspective. The IMS of the Radiation and Nuclear Safety Authority (STUK) is used as an example. The IMS of STUK monitors about 8500 persons mainly working in hospitals, industry and research centres. The current thermoluminescence dosemeter (TLD) system was introduced in 1992 and the whole service changed to TLDs in 1995. The quality system compatible with the quality standards was introduced in 1999. An application for accreditation to fulfill EN45001 and ISO/IEC Guide 25 was made in December 1999, accreditation was achieved in August 2000 by the Finnish Accreditation Service (FINAS). The considerations needed for the quality system to fulfill the requirements of the quality standards are reported.
Kim, Kyungil; Markman, Arthur B
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.
Vukovic, Nikola; Williams, John N
The factors that contribute to perceptual simulation during sentence comprehension remain underexplored. Extant research on perspective taking in language has largely focused on linguistic constraints, such as the role of pronouns in guiding perspective adoption. In the present study, we identify preferential usage of egocentric and allocentric reference frames in individuals, and test the two groups on a standard sentence-picture verification task. Across three experiments, we show that individual biases in spatial reference frame adoption observed in non-linguistic tasks influence visual simulation of perspective in language. Our findings suggest that typically reported grand-averaged effects may obscure important between-subject differences, and support proposals arguing for representational pluralism, where perceptual information is integrated dynamically and in a way that is sensitive to contextual and especially individual constraints.
Armstrong, Patrick Ian; Rounds, James
Career assessment methods often include measures of individual differences constructs, such as interests, personality, abilities, and values. Although many researchers have recently called for the development of integrated models, career counseling professionals have long faced the challenge of integrating this information into their practice. The…
Pach, Daniel; Yang-Strobel, Xiaoli; Lüdtke, Rainer; Roll, Stephanie; Icke, Katja; Brinkhaus, Benno; Witt, Claudia M
We aimed to compare the effectiveness of standardized and individualized acupuncture treatment in patients with chronic low back pain. A single-center randomized controlled single-blind trial was performed in a general medical practice in Germany run by a Chinese-born medical doctor trained in western and Chinese medicine. One hundred and fifty outpatients with chronic low back pain were randomly allocated to two groups (78 standardized and 72 individualized acupuncture). Patients received either standardized acupuncture or individualized acupuncture. Treatment encompassed between 10 and 15 treatments based on individual symptoms with two treatments per week. The main outcome measure was the area under the curve (AUC) summarizing eight weeks of daily rated pain severity measured with a visual analogue scale (0 mm = no pain, 100 mm = worst imaginable pain). No significant differences between groups were observed for the AUC (individualized acupuncture mean: 1768.7 (95% CI, 1460.4; 2077.1); standardized acupuncture 1482.9 (1177.2; 1788.7); group difference, 285.8 (-33.9; 605.5) P = 0.080). In this single-center trial, individualized acupuncture was not superior to standardized acupuncture for patients suffering from chronic pain. As a next step, a multicenter noninferiority study should be performed to investigate whether standardised acupuncture treatment for chronic low back pain might be applicable in a broader usual care setting. This trial is registered with ClinicalTrials.gov NCT00758017.
conducted by Sir Francis Galton . Galton’s view of intelligence was that it distinguished those individuals who had genius (e.g., demonstrated by making...genius must have more refined sensory and motor faculties. Thus, Galton argued, intelligence could be measured by assessing constructs such as visual
Hedges, Larry V.; Pustejovsky, James E.; Shadish, William R.
Single case designs are a set of research methods for evaluating treatment effects by assigning different treatments to the same individual and measuring outcomes over time and are used across fields such as behavior analysis, clinical psychology, special education, and medicine. Emerging standards for single case designs have focused attention on…
Matsuura, S; Royba, E; Akutsu, S N; Yanagihara, H; Ochiai, H; Kudo, Y; Tashiro, S; Miyamoto, T
Current standards for radiological protection of the public have been uniformly established. However, individual differences in radiosensitivity are suggested to exist in human populations, which could be caused by nucleotide variants of DNA repair genes. In order to verify if such genetic variants are responsible for individual differences in radiosensitivity, they could be introduced into cultured human cells for evaluation. This strategy would make it possible to analyse the effect of candidate nucleotide variants on individual radiosensitivity, independent of the diverse genetic background. However, efficient gene targeting in cultured human cells is difficult due to the low frequency of homologous recombination (HR) repair. The development of artificial nucleases has enabled efficient HR-mediated genome editing to be performed in cultured human cells. A novel genome editing strategy, 'transcription activator-like effector nuclease (TALEN)-mediated two-step single base pair editing', has been developed, and this was used to introduce a nucleotide variant associated with a chromosomal instability syndrome bi-allelically into cultured human cells to demonstrate that it is the causative mutation. It is proposed that this editing technique will be useful to investigate individual radiosensitivity.
Li, Jingguang; Tian, Moqian; Fang, Huizhen; Xu, Miao; Li, He; Liu, Jia
In daily life, one of the most common social tasks we perform is to recognize faces. However, the relation between face recognition ability and social activities is largely unknown. Here we ask whether individuals with better social skills are also better at recognizing faces. We found that extraverts who have better social skills correctly recognized more faces than introverts. However, this advantage was absent when extraverts were asked to recognize non-social stimuli (e.g., flowers). In particular, the underlying facet that makes extraverts better face recognizers is the gregariousness facet that measures the degree of inter-personal interaction. In addition, the link between extraversion and face recognition ability was independent of general cognitive abilities. These findings provide the first evidence that links face recognition ability to our daily activity in social communication, supporting the hypothesis that extraverts are better at decoding social information than introverts.
Evering, Vincent H. M.; Andriessen, Peter; Duijsters, Carola E. P. M.; Brogtrop, Jeroen; Derijks, Luc J. J.
Background This study was designed to evaluate whether standardizing total parenteral nutrition (TPN) is at least non-inferior to TPN with individualized composition in premature infants with a gestational age (GA) < 32 weeks. Methods In this retrospective cohort study, all preterm born in or transferred to Maxima Medical Center (MMC) within 24 hours after birth with a GA < 32 weeks were included. The individualized group (2011) was compared to the partially standardized group (2012) and completely standardized group (2014) consequently. The primary endpoint was difference in growth. Secondary endpoints included differences in electrolyte concentrations. Results A total of 299 preterm were included in this study. When comparing weight gain, the infants in the (partially) standardized group demonstrated significantly (P < 0.05) less weight loss during the first days of life and grew faster subsequently in the following days than the individualized TPN regimen. Furthermore, significant differences in abnormal serum sodium, chloride, calcium, creatinine, magnesium and triglycerides values were demonstrated. Conclusion TPN with a (partially) standardized composition revealed to be at least non-inferior to TPN with an individualized composition. PMID:28270894
relative to solitary task performance levels (e.g., North and Gopher, 1975; Parker, 1964; Sterky and Eysenck , 1965). In attempting such an analysis...Sterky, K. and Eysenck , H. J. Pursuit rotor performance as a function of different degrees of distraction. Life Sciences, 1965) 4, 889-897. Trankell, A
Discusses the following factors influencing learning: (1) environment; (2) emotional makeup; (3) persistence; (4) timing of learning; (5) teaching method; (6) cognitive style; (7) food intake; and (8) psychological factors, including the difference between analytical and global thinking. Discusses how to get a sense of one's personal learning…
Lee, Joanna C.; Tomblin, J. Bruce
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…
As is the case in traditional second language (L2) acquisition research, a major question in the field of L2 real-time sentence processing is the extent to which L2 learners process the input like native speakers. Where differences are observed, the underlying causes could be the influence of the learner's first language and/or differences…
This paper challenges the historiographical discontinuity established between earlier "anthropometric testing" and the arrival of "psychological testing" with Binet and Simon's intelligence test in 1905. After some conceptual clarifications, it deals with "word association": a kind of psychological experimentation and testing which became popular over the last two decades of the 19th century. First Galton's exploration are presented, followed by experiments performed at the Leipzig laboratory by Trautscholdt, and then Cattell and Bryant's collective testing. Additionally, I document the use of this method for the study of mental difference through the works of Münsterberg, Bourdon, Jastrow, Nevers and Calkins. The cases I present show how the method gave rise to various measurements and classifications. I conclude that the word association technique triggered reflection on mental "uniqueness", gender traits and the influence of education, among other topics. Moreover, it prepared the terrain and anticipated some basic attractions and problems intelligence testing would later encounter.
Damos, D. L.
This paper describes several experiments examining the source of individual differences in the experience of mental workload. Three sources of such differences were examined: information processing abilities, timesharing abilities, and personality traits/behavior patterns. On the whole, there was little evidence that individual differences in information processing abilities or timesharing abilities are related to perceived differences in mental workload. However, individuals with strong Type A coronary prone behavior patterns differed in both single- and multiple-task performance from individuals who showed little evidence of such a pattern. Additionally, individuals with a strong Type A pattern showed some dissociation between objective performance and the experience of mental workload.
Magne, Cyrille; Jordan, Deanna K; Gordon, Reyna L
This study investigated the electrophysiological markers of rhythmic expectancy during speech perception. In addition, given the large literature showing overlaps between cognitive and neural resources recruited for language and music, we considered a relation between musical aptitude and individual differences in speech rhythm sensitivity. Twenty adults were administered a standardized assessment of musical aptitude, and EEG was recorded as participants listened to sequences of four bisyllabic words for which the stress pattern of the final word either matched or mismatched the stress pattern of the preceding words. Words with unexpected stress patterns elicited an increased fronto-central mid-latency negativity. In addition, rhythm aptitude significantly correlated with the size of the negative effect elicited by unexpected iambic words, the least common type of stress pattern in English. The present results suggest shared neurocognitive resources for speech rhythm and musical rhythm.
Brunner, Thomas A
Dyads composed of unacquainted females (n=82) watched a cartoon while consuming salty aperitif snacks. The Affective Communication Test was used to measure nonverbal expressiveness. Computing intraclass correlation coefficients, the extent to which participants within dyads matched each other's food intake was analyzed. Food intake matched highly for dyads with two expressive individuals and moderately for dyads with one expressive participant. For dyads with two unexpressive participants, there was no evidence for matching behavior. Highly expressive people seem to be able to synchronize with others and thereby allow for close matching. This is the first study to show an influence of personality on matching consumption behavior.
... 10 Energy 2 2013-01-01 2013-01-01 false Individual protection standard for human intrusion. 63.321... Standards Human Intrusion Standard § 63.321 Individual protection standard for human intrusion. (a) DOE must determine the earliest time after disposal that the waste package would degrade sufficiently that a...
... 10 Energy 2 2014-01-01 2014-01-01 false Individual protection standard for human intrusion. 63.321... Standards Human Intrusion Standard § 63.321 Individual protection standard for human intrusion. (a) DOE must determine the earliest time after disposal that the waste package would degrade sufficiently that a...
... 10 Energy 2 2012-01-01 2012-01-01 false Individual protection standard for human intrusion. 63.321... Standards Human Intrusion Standard § 63.321 Individual protection standard for human intrusion. (a) DOE must determine the earliest time after disposal that the waste package would degrade sufficiently that a...
... 10 Energy 2 2011-01-01 2011-01-01 false Individual protection standard for human intrusion. 63.321... Standards Human Intrusion Standard § 63.321 Individual protection standard for human intrusion. (a) DOE must determine the earliest time after disposal that the waste package would degrade sufficiently that a...
... 10 Energy 2 2010-01-01 2010-01-01 false Individual protection standard for human intrusion. 63.321... Standards Human Intrusion Standard § 63.321 Individual protection standard for human intrusion. (a) DOE must determine the earliest time after disposal that the waste package would degrade sufficiently that a...
Chronicle, Edward P.; MacGregor, James N.; Lee, Michael; Ormerod, Thomas C.; Hughes, Peter
Results on human performance on the Traveling Salesman Problem (TSP) from different laboratories show high consistency. However, one exception is in the area of individual differences. While one research group has consistently failed to find systematic individual differences across instances of TSPs (Chronicle, MacGregor and Ormerod), another…
Bond, Charles F., Jr.; DePaulo, Bella M.
The authors report a meta-analysis of individual differences in detecting deception, confining attention to occasions when people judge strangers' veracity in real-time with no special aids. The authors have developed a statistical technique to correct nominal individual differences for differences introduced by random measurement error. Although…
English, S; Nakagawa, S; Clutton-Brock, T H
Although recent models for the evolution of personality, using game theory and life-history theory, predict that individuals should differ consistently in their cooperative behaviour, consistent individual differences in cooperative behaviour have rarely been documented. In this study, we used a long-term data set on wild meerkats to quantify the repeatability of two types of cooperative care (babysitting and provisioning) within individuals and examined how repeatability varied across age, sex and status categories. Contributions to babysitting and provisioning were significantly repeatable and positively correlated within individuals, with provisioning more repeatable than babysitting. While repeatability of provisioning was relatively invariant across categories of individuals, repeatability of babysitting increased with age and was higher for subordinates than dominants. These results provide support for theoretical predictions that life-history trade-offs favour the evolution of consistent individual differences in cooperative behaviour and raise questions about why some individuals consistently help more than others across a suite of cooperative behaviours.
Pan, Duo; Xue, Xiaobo; Zhang, Xiaogang; Chen, Jingbiao
Active optical frequency standard, or active optical clock, is a new concept of optical frequency standard, where a weak feedback with phase coherence information in optical bad-cavity limitation is formed, and the continuous self-sustained coherent stimulated emission between two atomic transition levels with population inversion is realized. Through ten years of both theoretical and experimental exploration, the narrow linewidth and suppression of cavity pulling effect of active optical frequency standard have been initially proved. In this paper, after a simple review, we will mainly present the most recent experimental progresses of active optical frequency standards in Peking University, including 4-level cesium active optical frequency standards and active Faraday optical frequency standards. The future development of active optical frequency standards is also discussed.
conversation with the flight instructor, with the skilled pilot who can easily excercise flight control, and converse in par- allel. A difference...The subjects tested were 35 twelve-year olds , who performed tasks singly first then two dual task pairs and then each singly again. McQueen’s results...conducted by Sverko (1977) on adults in an effort to find evidence for a general factor of time-sharing skill. This study was conducted in order to
Ferguson, Danielle R; Bailey, Michele M
This study assessed the reproductive performance of mice housed in 2 types of individually ventilated caging systems. Breeding pairs from 48 female and 24 male mice of 3 established transgenic mouse breeding colonies were placed in either a standard or disposable ventilated caging system. For 3 breeding cycles, the number of pups born, pup survival rate to weaning, time interval between litters, and pup weights were monitored for each breeding pair. Disposable and standard cages were maintained in the same location during breeding. Environmental parameters included intracage temperature, humidity, and ammonia and carbon dioxide levels and room light intensity and sound. Overall, 776 offspring were produced. Breeding performance did not differ significantly between the 2 cage types. By 11 wk of age, the weights of pups from both cage types were equivalent. The intracage temperature was 1.1 °F warmer and light intensity at the site of the nest was 34 lx dimmer in disposable cages than in standard caging. The difference in lighting likely was due to nest location; the nests in the disposable cages were at the back of the cages and away from the anterior air supply, whereas in standard caging, nests were at the front of the cages, with the air supply at the rear. Under these husbandry conditions, mice housed in disposable caging systems have comparable breeding performance to those housed in standard individually ventilated cages.
Cavalcanti, Paulo R.; Oliveira-Castro, Jorge M.; Foxall, Gordon R.
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…
Galtress, Tiffany; Garcia, Ana; Kirkpatrick, Kimberly
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…
Bilikozen, Neslihan; Akyel, Ayse
This study explores the relative contribution to EFL reading comprehension of the following individual-difference variables: prior knowledge, topic interest, linguistic proficiency, gender, reading motivation, and metacognitive awareness. It also investigates the relationship between the aforementioned individual differences and the role of text…
... Ground Water Protection Standards Severable? 197.38 Section 197.38 Protection of Environment... Disposal Additional Provisions § 197.38 Are the Individual Protection and Ground Water Protection Standards Severable? Yes. The individual protection and ground water protection standards are severable....
... is maintained at a pressure less than atmospheric pressure, then paragraph (a)(1)(i)(B) of this....355(h); and (3) The pressure is monitored continuously to ensure that the pressure in the individual drain system remains below atmospheric pressure. (ii) The closed-vent system and control device shall...
... is maintained at a pressure less than atmospheric pressure, then paragraph (a)(1)(i)(B) of this....355(h); and (3) The pressure is monitored continuously to ensure that the pressure in the individual drain system remains below atmospheric pressure. (ii) The closed-vent system and control device shall...
... is maintained at a pressure less than atmospheric pressure, then paragraph (a)(1)(i)(B) of this....355(h); and (3) The pressure is monitored continuously to ensure that the pressure in the individual drain system remains below atmospheric pressure. (ii) The closed-vent system and control device shall...
Slater, Stephanie J.; Schleigh, Sharon Price; Stork, Debra J.
The development of valid and reliable strategies to efficiently determine the knowledge landscape of introductory astronomy college students is an effort of great interest to the astronomy education community. This study examines individual item response rates from a widely used conceptual understanding survey, the Test Of Astronomy Standards…
Yovel, Galit; Wilmer, Jeremy B.; Duchaine, Brad
Faces are probably the most widely studied visual stimulus. Most research on face processing has used a group-mean approach that averages behavioral or neural responses to faces across individuals and treats variance between individuals as noise. However, individual differences in face processing can provide valuable information that complements and extends findings from group-mean studies. Here we demonstrate that studies employing an individual differences approach—examining associations and dissociations across individuals—can answer fundamental questions about the way face processing operates. In particular these studies allow us to associate and dissociate the mechanisms involved in face processing, tie behavioral face processing mechanisms to neural mechanisms, link face processing to broader capacities and quantify developmental influences on face processing. The individual differences approach we illustrate here is a powerful method that should be further explored within the domain of face processing as well as fruitfully applied across the cognitive sciences. PMID:25191241
Lambert, Alysa D.; Marler, Janet H.; Gueutal, Hal G.
This study investigated individual and organizational factors that predict an individual's choice to use flexible work arrangements (FWAs). Survey data was collected from 144 employees in two different organizations. The results revealed several significant predictors of FWAs: tenure, hours worked per week, supervisory responsibilities,…
Gingras, Bruno; Honing, Henkjan; Peretz, Isabelle; Trainor, Laurel J; Fisher, Simon E
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.
Gingras, Bruno; Honing, Henkjan; Peretz, Isabelle; Trainor, Laurel J.; Fisher, Simon E.
Advances in molecular technologies make it possible to pinpoint genomic factors associated with complex human traits. For cognition and behaviour, identification of underlying genes provides new entry points for deciphering the key neurobiological pathways. In the past decade, the search for genetic correlates of musicality has gained traction. Reports have documented familial clustering for different extremes of ability, including amusia and absolute pitch (AP), with twin studies demonstrating high heritability for some music-related skills, such as pitch perception. Certain chromosomal regions have been linked to AP and musical aptitude, while individual candidate genes have been investigated in relation to aptitude and creativity. Most recently, researchers in this field started performing genome-wide association scans. Thus far, studies have been hampered by relatively small sample sizes and limitations in defining components of musicality, including an emphasis on skills that can only be assessed in trained musicians. With opportunities to administer standardized aptitude tests online, systematic large-scale assessment of musical abilities is now feasible, an important step towards high-powered genome-wide screens. Here, we offer a synthesis of existing literatures and outline concrete suggestions for the development of comprehensive operational tools for the analysis of musical phenotypes. PMID:25646515
Ehrman, Madeline E.; Leaver, Betty Lou; Oxford, Rebecca L.
Offers a brief overview of the field of individual differences in language learning, especially as they are reflected in learning styles, learning strategies, and affective variables. Touches on areas for further research. (Author/VWL)
Farronato, Giampietro; Periti, Giulia; Giannini, Lucia; Farronato, Davide; Maspero, Cinzia
In this article the individual patient (IP) appliance is described. It consists of 250 options of bracket and band variations as the straight wire appliances. Increasing the bracket capabilities means using an increasing number of brackets, each with a specific design created for a treatment situation. The objective of IP appliance is to eliminate wire bending from orthodontic treatment and improve the treatment results. To manage this technique, a computer software is needed. Internet offers significant possibilities in managing each patient by patient basis. The clinician is required to make the diagnosis and treatment plan before ordering the appliance. Two clinical cases are described with the aim to present the advantages of this technique.
Herzmann, Grit; Kunina, Olga; Sommer, Werner; Wilhelm, Oliver
Individual differences in perceiving, learning, and recognizing faces, summarized under the term face cognition, have been shown on the behavioral and brain level, but connections between these levels have rarely been made. We used ERPs in structural equation models to determine the contributions of neurocognitive processes to individual differences in the accuracy and speed of face cognition as established by Wilhelm, Herzmann, Kunina, Danthiir, Schacht, and Sommer [Individual differences in face cognition, in press]. For 85 participants, we measured several ERP components and, in independent tasks and sessions, assessed face cognition abilities and other cognitive abilities, including immediate and delayed memory, mental speed, general cognitive ability, and object cognition. Individual differences in face cognition were unrelated to domain-general visual processes (P100) and to processes involved with memory encoding (Dm component). The ability of face cognition accuracy was moderately related to neurocognitive indicators of structural face encoding (latency of the N170) and of activating representations of both faces and person-related knowledge (latencies and amplitudes of the early and late repetition effects, ERE/N250 and LRE/N400, respectively). The ability of face cognition speed was moderately related to the amplitudes of the ERE and LRE. Thus, a substantial part of individual differences in face cognition is explained by the speed and efficiency of activating memory representations of faces and person-related knowledge. These relationships are not moderated by individual differences in established cognitive abilities.
Barrows, E M; Bell, W J; Michener, C D
The evolution of individual or subgroup differences in odors of halictine bees is suggested from possible widespread intraspecific variation in pheromones. An important result of such variation may be maintenance of genetic polymorphisms; in nesting Hymenoptera odor differences may also facilitate individual nest recognition. In Lasioglosum zephyrum males habituate to odors of different females and perhaps thus save time by not trying to copulate with nonreceptive individuals. Guards (females) at nest entrances distinguish their few nestmates (other females) from other conspecific individuals by odors, seemingly pheromones. Duration of the habituation in L. zephyrum is at least an hour (perhaps much more) for males in relation to females and 6 or 7 days for guards in relation to nestmates. Studies of pheromones should take into consideration the possibility of pheromonal polymorphism in any species and the likelihood that it may be significant from biological and practical viewpoints. PMID:1058498
Proulx, Michael J
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.
Molleman, Lucas; van den Berg, Pieter; Weissing, Franz J
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.
Proulx, Michael J.
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. PMID:22066030
Sörqvist, Patrik; Rönnberg, Jerker
This paper reviews the current literature on individual differences in susceptibility to the effects of background sound on visual-verbal task performance. A large body of evidence suggests that individual differences in working memory capacity (WMC) underpin individual differences in susceptibility to auditory distraction in most tasks and contexts. Specifically, high WMC is associated with a more steadfast locus of attention (thus overruling the call for attention that background noise may evoke) and a more constrained auditory-sensory gating (i.e., less processing of the background sound). The relation between WMC and distractibility is a general framework that may also explain distractibility differences between populations that differ along variables that covary with WMC (such as age, developmental disorders, and personality traits). A neurocognitive task-engagement/distraction trade-off (TEDTOFF) model that summarizes current knowledge is outlined and directions for future research are proposed. PMID:25632345
Voytchev, M; Behrens, R; Ambrosi, P; Radev, R; Chiaro, P
This article presents the evolution of the International Electrotechnical Commission (IEC) and the European standards for individual monitoring of ionising radiation issued, respectively, from the committees IEC/Sub Committee 45B and European Committee for Electro-technical Standardization/Technical Committee 45B 'Radiation protection instrumentation'. Standards for passive individual photon and beta dosimetry systems as well as those for active individual monitors are discussed. A neutron ambient dose equivalent (rate) meter standard and a technical report concerning the determination of uncertainty in measurement are also covered.
Palmer, Stephen E; Griscom, William S
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.
Zimmerman, Ryan D; Swider, Brian W; Woo, Sang Eun; Allen, David G
Psychological individual differences, such as personality, affectivity, and general mental ability, have been shown to predict numerous work-related behaviors. Although there is substantial research demonstrating relationships between psychological individual differences and withdrawal behaviors (i.e., lateness, absenteeism, and turnover), there is no integrative framework providing scholars and practitioners a guide for conceptualizing how, why, and under what circumstances we observe such relationships. In this integrative conceptual review we: (a) utilize the Cognitive-Affective Processing System framework (Mischel & Shoda, 1995) to provide an overarching theoretical basis for how psychological individual differences affect withdrawal behaviors; (b) create a theoretical model of the situated person that summarizes the existing empirical literature examining the effect of psychological differences on withdrawal behavior; and (c) identify future research opportunities based on our review and integrative framework.
Elementary school students differ in interest, capacity, achievement, social development, socioeconomic level, and psychomotor skills. These individual differences are discussed in reference to the process of designing the elementary social studies curriculum. Part One suggests ways in which teachers can respond to students' individual…
Siegler, Robert S.; Pyke, Aryn A.
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…
Bender, Timothy A.; Hom, Harry L., Jr.
Individual differences in achievement orientation are compared with differences in gifted students' use of feedback on a classroom exam. The achievement orientation of 57 seventh- and eighth-grade gifted students was measured using the Motivational Orientation Scale (MOS). There were 33 males and 24 females. As part of their regular classroom…
Weisberg, Steven M.; Schinazi, Victor R.; Newcombe, Nora S.; Shipley, Thomas F.; Epstein, Russell A.
There are marked individual differences in the formation of cognitive maps both in the real world and in virtual environments (VE; e.g., Blajenkova, Motes, & Kozhevnikov, 2005; Chai & Jacobs, 2010; Ishikawa & Montello, 2006; Wen, Ishikawa, & Sato, 2011). These differences, however, are poorly understood and can be difficult to…
Barnett, Kylie J.; Finucane, Ciara; Asher, Julian E.; Bargary, Gary; Corvin, Aiden P.; Newell, Fiona N.; Mitchell, Kevin J.
The term synaesthesia has been applied to a range of different sensory-perceptual and cognitive experiences, yet how these experiences are related to each other is not well understood. Not only are there disparate types of synaesthesia, but even within types there are vast individual differences in the way that stimuli induce synaesthesia and in…
Pearson, R. G.; Hart, F. D.; Obrien, J. F.
Individual variations in annoyance and in susceptibility to noise were studied to establish a finer definition of the ingredients of the human annoyance response. The study involved interactions among a heterogeneous sample of human subjects, various noise stimuli, and different physical environments of exposure. Significant differences in annoyance ratings among the six noise stimuli, all equated for peak sound pressure level, were found.
Belstrøm, Daniel; Holmstrup, Palle; Fiehn, Nils-Erik; Kirkby, Nikolai; Kokaras, Alexis; Paster, Bruce J.; Bardow, Allan
ABSTRACT 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 < 0.0001) and a twofold higher relative abundance of Neisseria, Haemophilus, and Fusobacterium were recorded in saliva samples from the healthy group compared with the caries group. Differences observed were more pronounced when limiting the analyses to caries-free individuals in each group. Data from this cross-sectional analysis suggest that low levels of caries experience might associate with a characteristic salivary bacterial composition different from that in individuals with high caries experience. Consequently, longitudinal studies are required to determine if the composition of the salivary microbiota might be a predictive factor of caries risk at the individual level. PMID:28326153
Golenia, Laura; Schoemaker, Marina M.; Mouton, Leonora J.; Bongers, Raoul M.
Many motor learning studies focus on average performance while it is known from everyday life experience that humans differ in their way of learning new motor tasks. This study emphasises the importance of recognizing individual differences in motor learning. We studied individual tool grasping profiles of individuals who learned to pick up objects with a novel tool, a pair of pliers. The pair of pliers was attached to the thumb and the index finger so that the tip of the thumb and the tip of the index finger were displaced to the beaks of the pair of pliers. The grasp component was manipulated by varying the location of the hinge of the pair of pliers, which resulted in different relations between beak opening and closing and finger opening and closing. The Wider Beak group had the hinge at 7 cm, the Same Beak group had the hinge at 10 cm (i.e., in the middle), and the Smaller Beak group had the hinge at 13 cm from the digits. Each group consisted of ten right-handed participants who picked up an object with one of the pairs of pliers 200 times on two subsequent days. Hand opening, plateau phase, hand closing, grasping time and maximum aperture were analyzed. To characterize individual changes over practice time, a log function was fitted on these dependent variables and the ratio of improvement was determined. Results showed that at the beginning stage of tool use learning the characteristic grasping profile consisted of three phases; hand opening, plateau phase and hand closing. Over practicing individual participants differed in the number of phases that changed, the amount of change in a phase and/or the direction of change. Moreover, with different pliers different learning paths were found. The importance of recognizing individual differences in motor learning is discussed. PMID:25386708
... individual institution minimum capital ratios. 615.5351 Section 615.5351 Banks and Banking FARM CREDIT... OPERATIONS Establishment of Minimum Capital Ratios for an Individual Institution § 615.5351 Standards for determination of appropriate individual institution minimum capital ratios. The appropriate minimum...
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... individual minimum capital ratios. 3.403 Section 3.403 Banks and Banking COMPTROLLER OF THE CURRENCY, DEPARTMENT OF THE TREASURY CAPITAL ADEQUACY STANDARDS Establishment of Minimum Capital Ratios for an... individual minimum capital ratios. The appropriate minimum capital ratios for an individual national bank...
... individual minimum capital ratios. 3.11 Section 3.11 Banks and Banking COMPTROLLER OF THE CURRENCY, DEPARTMENT OF THE TREASURY MINIMUM CAPITAL RATIOS; ISSUANCE OF DIRECTIVES Establishment of Minimum Capital Ratios for an Individual Bank § 3.11 Standards for determination of appropriate individual...
... individual institution minimum capital ratios. 615.5351 Section 615.5351 Banks and Banking FARM CREDIT... OPERATIONS Establishment of Minimum Capital Ratios for an Individual Institution § 615.5351 Standards for determination of appropriate individual institution minimum capital ratios. The appropriate minimum...
Carreira, María B; Cossio, Ricardo; Britton, Gabrielle B
Individual differences in responses to a novel environment are an important tool to predict predisposition to neuropsychiatric disorders. One way to examine individual differences involves classifying animals based on locomotion in a novel context. In this study we focused on individual and sex differences by categorizing female and male mice as high (HR) or low responders (LR) on the basis of open field locomotion. We then assessed whether groups differed on behavioral measures of spontaneous alternations, anxiety, depression and contextual fear conditioning. In the Y-maze, we observed no differences across HR/LR or sex on spontaneous alternations, but HR displayed more locomotion. HR male mice showed less anxiety-like behavior in the light-dark test but not the elevated plus maze. We observed no differences in the forced swim test across HR/LR, although males exhibited greater depression-like behavior overall. HR mice exhibited less contextual fear memory compared to LR regardless of sex. Principal component analyses suggested sex-specific patterns of behaviors across tests, with female responses within individual tests tending to load together. In females anxiety- and depression-like behaviors explained a large part of the variance observed across tests in our battery, whereas male behavior was primarily explained by variables related to locomotion.
Vidulich, Michael A.; Pandit, Parimal
Results by two groups of subjects, pilots and nonpilots, for two subjective workload assessment techniques (the SWAT and NASA-TLX tests) intended to evaluate individual differences in the perception and reporting of subjective workload are compared with results obtained for several traditional personality tests. The personality tests were found to discriminate between the groups while the workload tests did not. It is concluded that although the workload tests may provide useful information with respect to the interaction between tasks and personality, they are not effective as pure tests of individual differences.
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
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.
Hunley, Samuel B; Marker, Arwen M; Lourenco, Stella F
The current study investigated individual differences in the flexibility of peripersonal space (i.e., representational space near the body), specifically in relation to trait claustrophobic fear (i.e., fear of suffocating or being physically restricted). Participants completed a line bisection task with either a laser pointer (Laser condition), allowing for a baseline measure of the size of one's peripersonal space, or a stick (Stick condition), which produces expansion of one's peripersonal space. Our results revealed that individuals high in claustrophobic fear had larger peripersonal spaces than those lower in claustrophobic fear, replicating previous research. We also found that, whereas individuals low in claustrophobic fear demonstrated the expected expansion of peripersonal space in the Stick condition, individuals high in claustrophobic fear showed less expansion, suggesting decreased flexibility. We discuss these findings in relation to the defensive function of peripersonal space and reduced attentional flexibility associated with trait anxieties.
Siegler, Robert S; Pyke, Aryn A
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 2 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.
Rubin, Mark; Morrison, Tessa
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.
Prinzel, Lawrence J., III; DeVries, Holly; Freeman, Fred G.; Mikulka, Peter
Automation-induced complacency has been documented as a cause or contributing factor in many airplane accidents throughout the last two decades. It is surmised that the condition results when a crew is working in highly reliable automated environments in which they serve as supervisory controllers monitoring system states for occasional automation failures. Although many reports have discussed the dangers of complacency, little empirical research has been produced to substantiate its harmful effects on performance as well as what factors produce complacency. There have been some suggestions, however, that individual characteristics could serve as possible predictors of performance in automated systems. The present study examined relationship between the individual differences of complacency potential, boredom proneness, and cognitive failure, automation-induced complacency. Workload and boredom scores were also collected and analyzed in relation to the three individual differences. The results of the study demonstrated that there are personality individual differences that are related to whether an individual will succumb to automation-induced complacency. Theoretical and practical implications are discussed.
Salthouse, Timothy A.; And Others
Three hypotheses accounting for individual differences in spatial visualization ability were investigated in 2 experiments with 142 male undergraduates at Georgia Institute of Technology (Atlanta). Support was found for the preservation-under-transformation hypothesis, suggesting that effectiveness of storage during concurrent information…
McMurray, Bob; Samelson, Vicki M.; Lee, Sung Hee; Tomblin, J. Bruce
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…
Ackerman, Phillip L.; Kyllonen, Patrick C.; Roberts, Richard D.
In preparation for a conference on learning and individual differences, the invited authors prepared chapters, which were distributed in draft form. Presentations were followed by discussions, which were recorded, and then edited for this volume, so that the discussion transcript follows each paper. The chapters in part 1, General Background and…
Presents two empirical case studies concerning the role of individual differences in searching through a spatial-semantic virtual environment. Discusses information visualization in information systems; cognitive factors, including associative memory, spatial ability, and visual memory; user satisfaction; and cognitive abilities and search…
Armstrong, Patrick Ian; Day, Susan X.; McVay, Jason P.; Rounds, James
Using data from published sources, the authors investigated J. L. Holland's (1959, 1997) theory of interest types as an integrative framework for organizing individual differences variables that are used in counseling psychology. Holland's interest types were used to specify 2- and 3-dimensional interest structures. In Study 1, measures of…
Wang, Xiangpeng; Wang, Ting; Chen, Zhencai; Hitchman, Glenn; Liu, Yijun; Chen, Antao
Individuals differ in the ability to utilize previous conflict information to optimize current conflict resolution, which is termed the conflict adaptation effect. Previous studies have linked individual differences in conflict adaptation to distinct brain regions. However, the network-based neural mechanisms subserving the individual differences of the conflict adaptation effect have not been studied. The present study employed a psychophysiological interaction (PPI) analysis with a color-naming Stroop task to examine this issue. The main results were as follows: (1) the anterior cingulate cortex (ACC)-seeded PPI revealed the involvement of the salience network (SN) in conflict adaptation, while the posterior parietal cortex (PPC)-seeded PPI revealed the engagement of the central executive network (CEN). (2) Participants with high conflict adaptation effect showed higher intra-CEN connectivity and lower intra-SN connectivity; while those with low conflict adaptation effect showed higher intra-SN connectivity and lower intra-CEN connectivity. (3) The PPC-centered intra-CEN connectivity positively predicted the conflict adaptation effect; while the ACC-centered intra-SN connectivity had a negative correlation with this effect. In conclusion, our data demonstrated that conflict adaptation is likely supported by the CEN and the SN, providing a new perspective on studying individual differences in conflict adaptation on the basis of large-scale networks.
Thompson, Amy S.
Bilingualism (Sanz, 2000), motivation (Pintrich, 1989), and language aptitude (Grigorenko, Sternberg, and Ehrman, 2000) are crucial individual differences that contribute to successful adult language learning. Since Gardner's (1985) seminal work on motivation, many studies have shown that motivation is dynamic and that it affects language…
Vukovic, Rose K.; Fuchs, Lynn S.; Geary, David C.; Jordan, Nancy C.; Gersten, Russell; Siegler, Robert S.
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…
Prat, Chantel S.; Mason, Robert A.; Just, Marcel Adam
This study used fMRI to examine individual differences in the neural basis of causal inferencing. Participants with varying language skill levels, as indexed by scores on the vocabulary portion of the Nelson-Denny Reading Test, read four types of two-sentence passages in which causal relatedness (moderate and distant) and presence or absence of…
Kidd, Evan; Arciuli, Joanne
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)…
Misyak, Jennifer B.; Christiansen, Morten H.
Although statistical learning and language have been assumed to be intertwined, this theoretical presupposition has rarely been tested empirically. The present study investigates the relationship between statistical learning and language using a within-subject design embedded in an individual-differences framework. Participants were administered…
Colombo, John; Frick, Janet E.; Gorman, Sheila A.
Examined possibility that arousability as manifested in sensitization contributes to individual differences in infants' attentional profiles. Sensitization tended to occur more frequently with more complex than with less complex checkerboards. Infants showing sensitization looked longer and did not habituate as readily as infants who showed no…
Although the syntactic priming methodology is a promising tool for language acquisition researchers, using the technique with children raises issues that are not problematic in adult research. The current paper reports on an individual differences study that addressed some of these outstanding issues. (a) Does priming purely reflect syntactic…
Howe, Nina; Recchia, Holly
Research Findings: Sibling teaching and learning behaviors were investigated in 2 studies of children in early and middle childhood. Study 1 addressed individual differences in teaching/learning and associations with dyadic age, age gap, gender, birth order, and relationship quality in 71 middle-class dyads (firstborns M age = 81.54 months;…
Golestani, Narly; Zatorre, Robert J.
Perceptual training was employed to characterize individual differences in non-native speech sound learning. Fifty-nine adult English speakers were trained to distinguish the Hindi dental-retroflex contrast, as well as a tonal pitch contrast. Training resulted in overall group improvement in the ability to identify and to discriminate the phonetic…
Foxall, Gordon R.; Doyle, John R.; Yani-de-Soriano, Mirella; Wells, Victoria K.
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…
Smetana, Judith G.; Rote, Wendy M.; Jambon, Marc; Tasopoulos-Chan, Marina; Villalobos, Myriam; Comer, Jessamy
Developmental trajectories and individual differences in 70 American middle-income 2.5- to 4-year olds' moral judgments were examined 3 times across 1 year using latent growth modeling. At Wave 1, children distinguished hypothetical moral from conventional transgressions on all criteria, but only older preschoolers did so when rating deserved…
Everson, Howard T.; Millsap, Roger E.
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…
Conners, Frances A.; Loveall, Susan J.; Moore, Marie S.; Hume, Laura E.; Maddox, Christopher D.
The self-teaching hypothesis suggests that children learn orthographic structure of words through the experience of phonologically recoding them. The current study is an individual differences analysis of the self-teaching hypothesis. A total of 40 children in Grades 2 and 3 (7-9 years of age) completed tests of phonological recoding, word…
Wilson, Margaret Patricia
The effects of instructional variables and individual differences upon structural learning tasks were studied. Eighty college students were given pretasks to test mathematical problem solving and paired-associate (PA) learning skills. Each subject was then given two PA learning tasks presented in a study-test format. Kinship terms served as…
Royer, James M.; And Others
Individual differences in memory can be studied from two theoretical perspectives: Reappearance Theory or Constructive Theory. To test the Constructive Theory, two experiments examined the retention of high and low ability students. The results of both experiments supported the hypothesis that learners who acquire information rapidly also display…
Buda, Richard; Elsayed-Elkhouly, Sayed M.
Cultural differences between Arabs and Americans were investigated using the individualism-collectivism survey of J. Wagner (1995). Arab subjects (n=331) were significantly more collectivist than U.S. subjects (n=102), and within the Arab group, Egyptian subjects (n=224) were significantly more individualistic than Gulf States subjects.…
Libertus, Melissa E.; Brannon, Elizabeth M.
Previous studies have shown that as a group 6-month-old infants successfully discriminate numerical changes when the values differ by at least a 1:2 ratio but fail at a 2:3 ratio (e.g. 8 vs. 16 but not 8 vs. 12). However, no studies have yet examined individual differences in number discrimination in infancy. Using a novel numerical change…
Kable, Joseph W.; Levy, Ifat
In the last few years, neuroscientists have begun to identify associations between individual differences in decision-making and features of neuroanatomy and neurophysiology. Different tendencies in decision making, such as tolerance for risk, delay or effort, have been linked to various neurobiological measures, such as morphometry, structural connectivity, functional connectivity or the function of neurotransmitter systems. Though far from immutable, these neural features may nonetheless be suitable as relatively stable biomarkers for different decision traits. The establishment of such markers would achieve one of the stated goals of neuroeconomics, which is to improve the prediction of economic behavior across different contexts.
Elton, Amanda; Smith, Christopher T; Parrish, Michael H; Boettiger, Charlotte A
Excessively choosing immediate over larger future rewards, or delay discounting (DD), associates with multiple clinical conditions. Individual differences in DD likely depend on variations in the activation of and functional interactions between networks, representing possible endophenotypes for associated disorders, including alcohol use disorders (AUDs). Numerous fMRI studies have probed the neural bases of DD, but investigations of large-scale networks remain scant. We addressed this gap by testing whether activation within large-scale networks during Now/Later decision-making predicts individual differences in DD. To do so, we scanned 95 social drinkers (18-40 years old; 50 women) using fMRI during hypothetical choices between small monetary amounts available "today" or larger amounts available later. We identified neural networks engaged during Now/Later choice using independent component analysis and tested the relationship between component activation and degree of DD. The activity of two components during Now/Later choice correlated with individual DD rates: A temporal lobe network positively correlated with DD, whereas a frontoparietal-striatal network negatively correlated with DD. Activation differences between these networks predicted individual differences in DD, and their negative correlation during Now/Later choice suggests functional competition. A generalized psychophysiological interactions analysis confirmed a decrease in their functional connectivity during decision-making. The functional connectivity of these two networks negatively correlates with alcohol-related harm, potentially implicating these networks in AUDs. These findings provide novel insight into the neural underpinnings of individual differences in impulsive decision-making with potential implications for addiction and related disorders in which impulsivity is a defining feature.
Joyce, C. R. B.
The tendency of some individuals to report changes of physical and mental state after taking pharmacologically inert substances has been investigated experimentally. In a class of healthy medical students, those individuals who reported symptoms and those who did not made significantly different scores on a number of behavioural tests. The likely reactions of the members of a second class (containing none of the previous participants) to dummies were then predicted from their scores on the same tests, some of which were found to be much more efficient predictors than would have been expected by chance. Some implications for further research and for clinical medicine are discussed. PMID:14408028
Bauer, Daniel J; Reyes, Heathe Luz McNaughton
The proper use of statistical models for analyzing individual change over time is critical for the progress of developmental science. Latent curve models, hierarchical linear growth models, group-based trajectory models, and growth mixture models constitute increasingly important tools for longitudinal data analysis. To facilitate their understanding and use, this paper clarifies similarities and differences between these models, with particular attention to the assumptions they make about individual development. An example shows how the results and interpretation vary across model types. Discussion centers on reviewing the strengths and limitations of each approach for developmental research.
Wisniewski, Matthew G; Church, Barbara A; Mercado, Eduardo
Learning to distinguish subtle differences in objects or events can impact how one generalizes. In some cases, training can cause novel events to appear more familiar or attractive than those actually experienced during training: the peak shift effect. This study examined whether individual differences in learning led to systematic patterns of generalization. Participants were trained to identify simulated birdsongs, and then tested on their ability to identify a target song presented among several similar songs that differed in pitch. Initial analysis showed that those attaining moderate proficiency at discriminating songs during training were more likely to shift than those performing poorly or proficiently. However, a neural network trained to output individuals' gradient dynamics using only performance during training as input found an additional set of training variables that predicted shift. Specifically, one subset of shifters had highly conservative response biases accompanied by very little change to perceptual sensitivity in training. These findings suggest that discrimination learning may only lead to generalization shifts in some individuals, and that all individuals who shift may not do so for the same reason.
Gulbinaite, Rasa; Johnson, Addie; de Jong, Ritske; Morey, Candice C; van Rijn, Hedderik
Individuals scoring relatively high on measures of working memory tend to be more proficient at controlling attention to minimize the effect of distracting information. It is currently unknown whether such superior attention control abilities are mediated by stronger suppression of irrelevant information, enhancement of relevant information, or both. Here we used steady-state visual evoked potentials (SSVEPs) with the Eriksen flanker task to track simultaneously the attention to relevant and irrelevant information by tagging target and distractors with different frequencies. This design allowed us to dissociate attentional biasing of perceptual processing (via SSVEPs) and stimulus processing in the frontal cognitive control network (via time-frequency analyses of EEG data). We show that while preparing for the upcoming stimulus, high- and low-WMC individuals use different strategies: High-WMC individuals show attentional suppression of the irrelevant stimuli, whereas low-WMC individuals demonstrate attentional enhancement of the relevant stimuli. Moreover, behavioral performance was predicted by trial-to-trial fluctuations in strength of distractor-suppression for high-WMC participants. We found no evidence for WMC-related differences in cognitive control network functioning, as measured by midfrontal theta-band power. Taken together, these findings suggest that early suppression of irrelevant information is a key underlying neural mechanism by which superior attention control abilities are implemented.
Russell, Michael J; Goodman, Theodore; Pierson, Ronald; Shepherd, Shane; Wang, Qiang; Groshong, Bennett; Wiley, David F
Transcranial electrical stimulation (TCES) is effective in treating many conditions, but it has not been possible to accurately forecast current density within the complex anatomy of a given subject's head. We sought to predict and verify TCES current densities and determine the variability of these current distributions in patient-specific models based on magnetic resonance imaging (MRI) data. Two experiments were performed. The first experiment estimated conductivity from MRIs and compared the current density results against actual measurements from the scalp surface of 3 subjects. In the second experiment, virtual electrodes were placed on the scalps of 18 subjects to model simulated current densities with 2 mA of virtually applied stimulation. This procedure was repeated for 4 electrode locations. Current densities were then calculated for 75 brain regions. Comparison of modeled and measured external current in experiment 1 yielded a correlation of r = .93. In experiment 2, modeled individual differences were greatest near the electrodes (ten-fold differences were common), but simulated current was found in all regions of the brain. Sites that were distant from the electrodes (e.g. hypothalamus) typically showed two-fold individual differences. MRI-based modeling can effectively predict current densities in individual brains. Significant variation occurs between subjects with the same applied electrode configuration. Individualized MRI-based modeling should be considered in place of the 10-20 system when accurate TCES is needed. PMID:24285948
Ilies, Remus; Wagner, David T; Morgeson, Frederick P
To expand on the understanding of how affective states are linked within teams, the authors describe a longitudinal study examining the linkages between team members' affective states over time. In a naturalistic team performance setting, they found evidence that the average affective state of the other team members was related to an individual team member's affect over time, even after controlling for team performance. In addition, they found that these affective linkages were moderated by individual differences in susceptibility to emotional contagion and collectivistic tendencies such that the strength of the linkage was stronger for those high in susceptibility and those with collectivistic tendencies. Implications for research and practice are discussed.
Larcom, Mary Jo
Previous research has suggested that emotion regulation improves with age. This study examined both age and individual differences in online emotion regulation after a negative mood induction. We found evidence that older adults were more likely to rapidly regulate their emotions than were younger adults. Moreover, older adults who rapidly regulated had lower trait anxiety and depressive symptoms and higher levels of optimism than their same-age peers who did not rapidly regulate. Measuring mood change over an extended time revealed that older rapid regulators still reported increased levels of positive affect over 20 min later, whereas young adult rapid regulators’ moods had declined. These results highlight the importance of considering individual differences when examining age differences in online emotion regulation. PMID:19808810
Libertus, Melissa E; Brannon, Elizabeth M
Previous studies have shown that as a group 6-month-old infants successfully discriminate numerical changes when the values differ by at least a 1:2 ratio but fail at a 2:3 ratio (e.g. 8 vs. 16 but not 8 vs. 12). However, no studies have yet examined individual differences in number discrimination in infancy. Using a novel numerical change detection paradigm, we present more direct evidence that infants' numerical perception is ratio-dependent even within the range of discriminable ratios and thus adheres to Weber's Law. Furthermore, we show that infants' numerical discrimination at 6 months reliably predicts their numerical discrimination abilities but not visual short-term memory at 9 months. Thus, individual differences in numerical discrimination acuity may be stable within the first year of life and provide important avenues for future longitudinal research exploring the relationship between infant numerical discrimination and later developing math achievement.
Golestani, Narly; Zatorre, Robert J
Perceptual training was employed to characterize individual differences in non-native speech sound learning. Fifty-nine adult English speakers were trained to distinguish the Hindi dental-retroflex contrast, as well as a tonal pitch contrast. Training resulted in overall group improvement in the ability to identify and to discriminate the phonetic and the tonal contrasts, but there were considerable individual differences in performance. A category boundary effect during the post-training discrimination of the Hindi but not of the tonal contrast suggests different learning mechanisms for these two stimulus types. Specifically, our results suggest that successful learning of the speech sounds involves the formation of a long-term memory category representation for the new speech sound.
Buss, David M
Although evolutionary psychology has been successful in explaining some species-typical and sex-differentiated adaptations, a large question that has largely eluded the field is this: How can the field successfully explain personality and individual differences? This article highlights some promising theoretical directions for tackling this question. These include life-history theory, costly signaling theory, environmental variability in fitness optima, frequency-dependent selection, mutation load, and flexibly contingent shifts in strategy according to environmental conditions. Tackling the explanatory question also requires progress on three fronts: (a) reframing some personality traits as forms of strategic individual differences; (b) providing a nonarbitrary, evolutionary-based formulation of environments as distributions and salience profiles of adaptive problems; and (c) identifying which strategies thrive and which falter in these differing problem-defined environments.
MacNamara, Annmarie; Rabinak, Christine A; Fitzgerald, Daniel A; Zhou, Xiaohong Joe; Shankman, Stewart A; Milad, Mohammed R; Phan, K Luan
Variability in fear conditionability is common, and clarity regarding the neural regions responsible for individual differences in fear conditionability could uncover brain-based biomarkers of resilience or vulnerability to trauma-based psychopathologies (e.g., post-traumatic stress disorder). In recent years, neuroimaging work has yielded a detailed understanding of the neural mechanisms underlying fear conditioning common across participants, however only a minority of studies have investigated the brain basis of inter-individual variation in fear learning. Moreover, the majority of these studies have employed small sample sizes (mean n=17; range n=5-27) and all have failed to meet the minimum recommended sample size for functional magnetic resonance imaging (fMRI) studies of individual differences. Here, using fMRI, we analyzed blood-oxygenation level dependent (BOLD) response recorded simultaneously with skin conductance response (SCR) and ratings of unconditioned stimulus (US) expectancy in 49 participants undergoing Pavlovian fear conditioning. On average, participants became conditioned to the conditioned stimulus (CS+; higher US expectancy ratings and SCR for the CS+ compared to the unpaired conditioned stimulus, CS-); the CS+ also robustly increased activation in the bilateral insula. Amygdala activation was revealed from a regression analysis that incorporated individual differences in fear conditionability (i.e., a between-subjects regressor of mean CS+>CS- SCR). By replicating results observed using much smaller sample sizes, the results confirm that variation in amygdala reactivity covaries with individual differences in fear conditionability. The link between behavior (SCR) and brain (amygdala reactivity) may be a putative endophenotype for the acquisition of fear memories.
Sperlich, Paula F; Holmberg, Hans-Christer; Reed, Jennifer L; Zinner, Christoph; Mester, Joachim; Sperlich, Billy
The purpose of this study was to determine whether an individually designed incremental exercise protocol results in greater rates of oxygen uptake (VO2max) than standardized testing. Fourteen well-trained, male runners performed five incremental protocols in randomized order to measure their VO2max: i) an incremental test (INCS+I) with pre-defined increases in speed (2 min at 8.64 km·h(-1), then a rise of 1.44 km·h(-1) every 30 s up to 14.4 km·h(-1)) and thereafter inclination (0.5° every 30 s); ii) an incremental test (INCI) at constant speed (14.4 km·h(-1)) and increasing inclination (2° every 2 min from the initial 0°); iii) an incremental test (INCS) at constant inclination (0°) and increasing speed (0.5 km·h(-1) every 30 s from the initial 12.0 km·h(-1)); iv) a graded exercise protocol (GXP) at a 1° incline with increasing speed (initially 8.64 km·h(-1) + 1.44 km·h(-1) every 5 min); v) an individual exercise protocol (INDXP) in which the runner chose the inclination and speed. VO2max was lowest (-4.2%) during the GXP (p = 0.01; d = 0.06-0.61) compared to all other tests. The highest rating of perceived exertion, heart rate, ventilation and end-exercise blood lactate concentration were similar between the different protocols (p < 0.05). The time to exhaustion ranged from 7 min 18 sec (INCS) to 25 min 30 sec (GXP) (p = 0.01).The VO2max attained by employing an individual treadmill protocol does not differ from the values derived from various standardized incremental protocols. Key pointsThe mean maximum oxygen uptake during the GXP was lower than for all other tests.Differences in the maximum rate of oxygen uptake between the various protocols exhibited considerable inter-individual variation.From the current findings, it can be concluded that well trained athletes are able to perform an individually designed treadmill running protocol.
Robinson, Terry E.; Yager, Lindsay M.; Cogan, Elizabeth S.; Saunders, Benjamin T.
Cues associated with rewards, such as food or drugs of abuse, can themselves acquire motivational properties. Acting as incentive stimuli, such cues can exert powerful control over motivated behavior, and in the case of cues associated with drugs, they can goad continued drug-seeking behavior and relapse. However, recent studies reviewed here suggest that there are large individual differences in the extent to which food and drug cues are attributed with incentive salience. Rats prone to approach reward cues (sign-trackers) attribute greater motivational value to discrete localizable cues and interoceptive cues than do rats less prone to approach reward cues (goal-trackers). In contrast, contextual cues appear to exert greater control over motivated behavior in goal-trackers than sign-trackers. It is possible to predict, therefore, before any experience with drugs, in which animals specific classes of drug cues will most likely reinstate drug-seeking behavior. The finding that different individuals may be sensitive to different triggers capable of motivating behavior and producing relapse suggests there may be different pathways to addiction, and has implications for thinking about individualized treatment. PMID:23748094
Shaw, Heather; Ellis, David A; Kendrick, Libby-Rae; Ziegler, Fenja; Wiseman, Richard
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.
Ou, Jinghua; Law, Sam-Po; Fung, Roxana
A growing body of research has suggested that cognitive abilities may play a role in individual differences in speech processing. The present study took advantage of a widespread linguistic phenomenon of sound change to systematically assess the relationships between speech processing and various components of attention and working memory in the auditory and visual modalities among typically developed Cantonese-speaking individuals. The individual variations in speech processing are captured in an ongoing sound change-tone merging in Hong Kong Cantonese, in which typically developed native speakers are reported to lose the distinctions between some tonal contrasts in perception and/or production. Three groups of participants were recruited, with a first group of good perception and production, a second group of good perception but poor production, and a third group of good production but poor perception. Our findings revealed that modality-independent abilities of attentional switching/control and working memory might contribute to individual differences in patterns of speech perception and production as well as discrimination latencies among typically developed speakers. The findings not only have the potential to generalize to speech processing in other languages, but also broaden our understanding of the omnipresent phenomenon of language change in all languages.
... 40 Protection of Environment 25 2011-07-01 2011-07-01 false Are the Individual Protection and Ground Water Protection Standards Severable? 197.38 Section 197.38 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) RADIATION PROTECTION PROGRAMS PUBLIC HEALTH AND ENVIRONMENTAL RADIATION PROTECTION STANDARDS FOR YUCCA...
Corbett, Michael J.
With the rise of network society, consumerism, individualization, globalization and contemporary change forces, students are pressured to both perform well in standardized academic assessments while at the same time constructing a non-standard, unique project of the self. I argue that this generates a particular set of place-based tensions for…
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
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
Lackner, J. R.; DiZio, P.
Space motion sickness is a significant operational concern in the American and Soviet space programs. Nearly 70% of all astronauts and cosmonauts are affected to some degree during their first several days of flight. It is now beginning to appear that space motion sickness like terrestrial motion sickness is the consequence of multiple etiological factors. As we come to understand basic mechanisms of spatial orientation and sensory-motor adaptation we can begin to predict etiological factors in different motion environments. Individuals vary greatly in the extent to which they are susceptible to these different factors. However, individuals seem to be relatively self-consistent in terms of their rates of adaptation to provocative stimulation and their retention of adaptation. Attempts to relate susceptibility to motion sickness during the microgravity phases of parabolic flight maneuvers to vestibular function under 1G and 0G test conditions are described.
Learning Styles and Cognitive Strategies in the Training Process 6 Non-cognitive training characteristics 12 Aptitude-Performance Interactions 18 Testing...differences in training environments appears in four general research areas. These include the study of: (1) trainee cognitive strategies, learning styles , and...However, among factors least likely to be given serious attention are the learning styles , cognitive strategies, and sensory modalities of individual
training. A general review of the researh effort as well as a .pecific discussion of the research conducted during 1 October 1979 to Septem~her P1...1977. I Savage, R. E., Williges, R. C., and Williges, B. H. Individual differences in motor skill training. Paper presented at the Sixth Psychology in...Paper presented at the Sixth Psychology in the DoD Symposium, April, 1979. Williges, R. C. and Williges, B. H. Automated motor skills training
2011 4. TITLE Predicting Individual Differences in Response to Sleep Loss 5a. Contract Number: 5b. Grant Number: 5c. Program Element Number: 5d...ADDRESS(ES) Naval Medical Reserach Unit – Dayton 2624 Q St., Bldg. 851, Area B Wright-Patterson AFB, OH 45433 8. PERFORMING ORGANIZATION... Program Department of the Navy 2300 E Street, NW Washington, DC 20372-5300 10. SPONSOR/MONITOR’S ACRONYM(S) BUMED 11. SPONSOR/MONITOR’S REPORT
This paper presents the rationale for a questionnaire measure of individual differences in stimulus screening--namely, individual differences in automatic screening of irrelevant stimuli and rapid habituation to distracting, irrelevant stimuli. All components of the questionnaire were intercorrelated and represented a unitary dimension of…
Barnes, Kelly Anne; Anderson, Kevin M; Plitt, Mark; Martin, Alex
When humans are provided with ample time to make a decision, individual differences in strategy emerge. Using an adaptation of a well-studied decision making paradigm, motion direction discrimination, we probed the neural basis of individual differences in strategy. We tested whether strategies emerged from moment-to-moment reconfiguration of functional brain networks involved in decision making with task-evoked functional MRI (fMRI) and whether intrinsic properties of functional brain networks, measured at rest with functional connectivity MRI (fcMRI), were associated with strategy use. We found that human participants reliably selected one of two strategies across 2 days of task performance, either continuously accumulating evidence or waiting for task difficulty to decrease. Individual differences in decision strategy were predicted both by the degree of task-evoked activation of decision-related brain regions and by the strength of pretask correlated spontaneous brain activity. These results suggest that spontaneous brain activity constrains strategy selection on perceptual decisions.
Prat, Chantel S; Just, Marcel Adam
This study used functional magnetic resonance imaging to investigate individual differences in the neural underpinnings of sentence comprehension, with a focus on neural adaptability (dynamic configuration of neural networks with changing task demands). Twenty-seven undergraduates, with varying working memory capacities and vocabularies, read sentences that were either syntactically simple or complex under conditions of varying extrinsic working memory demands (sentences alone or preceded by to-be-remembered words or nonwords). All readers showed greater neural adaptability when extrinsic working memory demands were low, suggesting that adaptability is related to resource availability. Higher capacity readers showed greater neural adaptability (greater increase in activation with increasing syntactic complexity) across conditions than did lower capacity readers. Higher capacity readers also showed better maintenance of or increase in synchronization of activation between brain regions as tasks became more demanding. Larger vocabulary was associated with more efficient use of cortical resources (reduced activation in frontal regions) in all conditions but was not associated with greater neural adaptability or synchronization. The distinct characterizations of verbal working memory capacity and vocabulary suggest that dynamic facets of brain function such as adaptability and synchronization may underlie individual differences in more general information processing abilities, whereas neural efficiency may more specifically reflect individual differences in language experience.
Rhodes, Gillian; Jeffery, Linda; Taylor, Libby; Hayward, William G; Ewing, Louise
Despite their similarity as visual patterns, we can discriminate and recognize many thousands of faces. This expertise has been linked to 2 coding mechanisms: holistic integration of information across the face and adaptive coding of face identity using norms tuned by experience. Recently, individual differences in face recognition ability have been discovered and linked to differences in holistic coding. Here we show that they are also linked to individual differences in adaptive coding of face identity, measured using face identity aftereffects. Identity aftereffects correlated significantly with several measures of face-selective recognition ability. They also correlated marginally with own-race face recognition ability, suggesting a role for adaptive coding in the well-known other-race effect. More generally, these results highlight the important functional role of adaptive face-coding mechanisms in face expertise, taking us beyond the traditional focus on holistic coding mechanisms.
Selvaggi, Gennaro; Dhejne, Cecilia; Landen, Mikael; Elander, Anna
The World Professional Association for Transgender Health (WPATH) currently publishes the Standards of Care (SOC), to provide clinical guidelines for health care of transsexual, transgender and gender non-conforming persons in order to maximize health and well-being by revealing gender dysphoria. An updated version (7th version, 2011) of the WPATH SOC is currently available. Differences between the 6th and the 7th versions of the SOC are shown; the SOC relevant to penile reconstruction in female-to-male (FtM) persons are emphasized, and we analyze how the 2011 WPATH SOC is influencing the daily practice of physicians involved in performing a penile reconstruction procedure for these patients. Depending by an individual's goals and expectations, the most appropriate surgical technique should be performed: the clinic performing penile reconstruction should be able to offer the whole range of techniques, such as: metoidioplasty, pedicle and free flaps phalloplasty procedures. The goals that physicians and health care institutions should achieve in the next years, in order to improve the care of female-to-male persons, consist in: informing in details the individuals applying for penile reconstruction about all the implications; referring specific individuals to centers capable to deliver a particular surgical technique; implementing the surgery with the most updated refinements. PMID:22654902
Zinbarg, R E; Mohlman, J
Two studies were conducted to test the predictions derived from the behavioral activation system and behavioral inhibition system theory of personality that trait anxiety is positively related to the speed of acquisition of punishment expectancies and impulsivity is positively related to the speed of acquisition of reward expectancies. Both studies used a standard approach-avoidance discrimination task with self-report measures of expectancies. Both studies found support for the hypothesized relation between trait and acquisition of punishment expectancies but not for the hypothesized relation between impulsivity and acquisition of reward expectancies. Study 2 suggested that the relation between trait anxiety and punishment expectancy is affected by the type of incentive and the type of trait anxiety measure used. The results suggest that highly trait anxious individuals are more susceptible to developing new sources of anxiety than others.
Nunez, Michael D; Srinivasan, Ramesh; Vandekerckhove, Joachim
Sequential sampling decision-making models have been successful in accounting for reaction time (RT) and accuracy data in two-alternative forced choice tasks. These models have been used to describe the behavior of populations of participants, and explanatory structures have been proposed to account for between individual variability in model parameters. In this study we show that individual differences in behavior from a novel perceptual decision making task can be attributed to (1) differences in evidence accumulation rates, (2) differences in variability of evidence accumulation within trials, and (3) differences in non-decision times across individuals. Using electroencephalography (EEG), we demonstrate that these differences in cognitive variables, in turn, can be explained by attentional differences as measured by phase-locking of steady-state visual evoked potential (SSVEP) responses to the signal and noise components of the visual stimulus. Parameters of a cognitive model (a diffusion model) were obtained from accuracy and RT distributions and related to phase-locking indices (PLIs) of SSVEPs with a single step in a hierarchical Bayesian framework. Participants who were able to suppress the SSVEP response to visual noise in high frequency bands were able to accumulate correct evidence faster and had shorter non-decision times (preprocessing or motor response times), leading to more accurate responses and faster response times. We show that the combination of cognitive modeling and neural data in a hierarchical Bayesian framework relates physiological processes to the cognitive processes of participants, and that a model with a new (out-of-sample) participant's neural data can predict that participant's behavior more accurately than models without physiological data.
Cussen, Victoria A
Both the number and breadth of avian cognition studies have expanded in the past three decades. Parrots have a long history as subjects in avian cognition research. This paper summarizes results from a number of parrot species tested on basic learning, and physical & social cognitive processes, with an emphasis on individual differences. Early psittacine studies were aimed at demonstrating a particular cognitive ability existed in a given species. Because of this proof of capacity focus, early studies typically included only a single individual or a dyad of parrots. Existing reviews of parrot cognition tend to focus on a particular cognitive component in a single species, or even a single individual. Despite the narrow focus, results from increasing sample sizes show intraspecific variation across a variety of cognitive assessments and parrot species. Intraspecific variability in performance on cognitive tasks highlights the need for establishing a cognitive normal range for a given species and process. To accomplish this, large numbers of individuals need to be tested and non-cognitive sources of variability need to be controlled. Once species typical cognitive normal ranges are established, cognitive comparisons can be made between parrot species and between parrots and other taxa.
Rodriguez-Fornells, Antoni; Krämer, Ulrike M; Lorenzo-Seva, Urbano; Festman, Julia; Münte, Thomas F
Language switching is omnipresent in bilingual individuals. In fact, the ability to switch languages (code switching) is a very fast, efficient, and flexible process that seems to be a fundamental aspect of bilingual language processing. In this study, we aimed to characterize psychometrically self-perceived individual differences in language switching and to create a reliable measure of this behavioral pattern by introducing a bilingual switching questionnaire. As a working hypothesis based on the previous literature about code switching, we decomposed language switching into four constructs: (i) L1 switching tendencies (the tendency to switch to L1; L1-switch); (ii) L2 switching tendencies (L2-switch); (iii) contextual switch, which indexes the frequency of switches usually triggered by a particular situation, topic, or environment; and (iv) unintended switch, which measures the lack of intention and awareness of the language switches. A total of 582 Spanish-Catalan bilingual university students were studied. Twelve items were selected (three for each construct). The correlation matrix was factor-analyzed using minimum rank factor analysis followed by oblique direct oblimin rotation. The overall proportion of common variance explained by the four extracted factors was 0.86. Finally, to assess the external validity of the individual differences scored with the new questionnaire, we evaluated the correlations between these measures and several psychometric (language proficiency) and behavioral measures related to cognitive and attentional control. The present study highlights the importance of evaluating individual differences in language switching using self-assessment instruments when studying the interface between cognitive control and bilingualism.
Rodriguez-Fornells, Antoni; Krämer, Ulrike M.; Lorenzo-Seva, Urbano; Festman, Julia; Münte, Thomas F.
Language switching is omnipresent in bilingual individuals. In fact, the ability to switch languages (code switching) is a very fast, efficient, and flexible process that seems to be a fundamental aspect of bilingual language processing. In this study, we aimed to characterize psychometrically self-perceived individual differences in language switching and to create a reliable measure of this behavioral pattern by introducing a bilingual switching questionnaire. As a working hypothesis based on the previous literature about code switching, we decomposed language switching into four constructs: (i) L1 switching tendencies (the tendency to switch to L1; L1-switch); (ii) L2 switching tendencies (L2-switch); (iii) contextual switch, which indexes the frequency of switches usually triggered by a particular situation, topic, or environment; and (iv) unintended switch, which measures the lack of intention and awareness of the language switches. A total of 582 Spanish–Catalan bilingual university students were studied. Twelve items were selected (three for each construct). The correlation matrix was factor-analyzed using minimum rank factor analysis followed by oblique direct oblimin rotation. The overall proportion of common variance explained by the four extracted factors was 0.86. Finally, to assess the external validity of the individual differences scored with the new questionnaire, we evaluated the correlations between these measures and several psychometric (language proficiency) and behavioral measures related to cognitive and attentional control. The present study highlights the importance of evaluating individual differences in language switching using self-assessment instruments when studying the interface between cognitive control and bilingualism. PMID:22291668
Noble, Kimberly G; McCandliss, Bruce D; Farah, Martha J
Socioeconomic status (SES) is associated with childhood cognitive achievement. In previous research we found that this association shows neural specificity; specifically we found that groups of low and middle SES children differed disproportionately in perisylvian/language and prefrontal/executive abilities relative to other neurocognitive abilities. Here we address several new questions: To what extent does this disparity between groups reflect a gradient of SES-related individual differences in neurocognitive development, as opposed to a more categorical difference? What other neurocognitive systems differ across individuals as a function of SES? Does linguistic ability mediate SES differences in other systems? And how do specific prefrontal/executive subsystems vary with SES? One hundred and fifty healthy, socioeconomically diverse first-graders were administered tasks tapping language, visuospatial skills, memory, working memory, cognitive control, and reward processing. SES explained over 30% of the variance in language, and a smaller but highly significant portion of the variance in most other systems. Statistically mediating factors and possible interventional approaches are discussed.
Van Hedger, Stephen C; Heald, Shannon L M; Koch, Rachelle; Nusbaum, Howard C
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
Dang, Junhua; Xiao, Shanshan; Liu, Ying; Jiang, Yumeng; Mao, Lihua
Initial exertion of self-control impairs subsequent self-regulatory performance, which is referred to as the ego depletion effect. The current study examined how individual differences in dopamine level, as indexed by eye blink rate (EBR), would moderate ego depletion. An inverted-U-shaped relationship between EBR and subsequent self-regulatory performance was found when participants initially engaged in self-control but such relationship was absent in the control condition where there was no initial exertion, suggesting individuals with a medium dopamine level may be protected from the typical ego depletion effect. These findings are consistent with a cognitive explanation which considers ego depletion as a phenomenon similar to "switch costs" that would be neutralized by factors promoting flexible switching.
Granqvist, Pehr; Mikulincer, Mario; Shaver, Phillip R
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.
Olderbak, Sally; Wilhelm, Oliver
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; ntotal = 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
Nesil, Tanseli; Kanit, Lutfiye; Collins, Allan C; Pogun, Sakire
To study individual differences in nicotine preference and intake, male and female rats were given free access to a choice of oral nicotine (10 or 20 mg/L) or water for 24 h/day for periods of at least six weeks, starting at adolescence or adulthood. A total of 341 rats, were used in four different experiments; weight, nicotine intake and total liquid consumption were recorded weekly. Results show that rats can discriminate nicotine from water, can regulate their intake, and that there are readily detected individual differences in nicotine preference. Ward analyses indicated that the animals could be divided into minimum, median and maximum preferring subgroups in all experiments. The effect of saccharine on nicotine intake was also evaluated; although the addition of saccharine increased total intake, rats drank unsweetened nicotine solutions and those with higher preferences for nicotine, preferred nicotine over water with or without saccharine added. Nicotine reduced weight gain and the effect was more pronounced in females than males. The average nicotine consumption of adolescent rats was higher than adults and nicotine exposure during adolescence reduced nicotine intake in adult rats. About half of the rats which had access to nicotine as adolescents and also as adults had a persistent pattern of consumption; the behavior was very stable in the female minimum preferring groups and a much higher ratio of rats sustained their adolescent behavior as adults. The change in preference was more pronounced when there was an interval between adolescent and adult exposure; female rats showed a more stable behavior than males suggesting a greater role for environmental influences on males. In conclusion, marked individual differences were observed in oral nicotine intake as measured in a continuous access 2-bottle choice test. Age and sex of the subjects and previous exposure to nicotine are significant factors which affect preference in rats.
McMurray, Bob; Samelson, Vicki M.; Lee, Sung Hee; Tomblin, J. Bruce
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 important implications for work on language impairment. The present study begins to fill this gap by relating individual differences in overall language ability to variation in online word recognition processes. Using the visual world paradigm, we evaluated online spoken word recognition in adolescents who varied in both basic language abilities and non-verbal cognitive abilities. Eye movements to target, cohort and rhyme objects were monitored during spoken word recognition, as an index of lexical activation. Adolescents with poor language skills showed fewer looks to the target and more fixations to the cohort and rhyme competitors. These results were compared to a number of variants of the TRACE model (McClelland & Elman, 1986) that were constructed to test a range of theoretical approaches to language impairment: impairments at sensory and phonological levels; vocabulary size, and generalized slowing. None were strongly supported, and variation in lexical decay offered the best fit. Thus, basic word recognition processes like lexical decay may offer a new way to characterize processing differences in language impairment. PMID:19836014
Biswal, Bharat B.; Eldreth, Dana A.; Motes, Michael A.
Recent advances in neuroimaging have permitted testing of hypotheses regarding the neural bases of individual differences, but this burgeoning literature has been characterized by inconsistent results. To test the hypothesis that differences in task demands could contribute to between-study variability in brain-behavior relationships, we had participants perform 2 tasks that varied in the extent of cognitive involvement. We examined connectivity between brain regions during a low-demand vigilance task and a higher-demand digit–symbol visual search task using Granger causality analysis (GCA). Our results showed 1) Significant differences in numbers of frontoparietal connections between low- and high-demand tasks 2) that GCA can detect activity changes that correspond with task-demand changes, and 3) faster participants showed more vigilance-related activity than slower participants, but less visual-search activity. These results suggest that relatively low-demand cognitive performance depends on spontaneous bidirectionally fluctuating network activity, whereas high-demand performance depends on a limited, unidirectional network. The nature of brain-behavior relationships may vary depending on the extent of cognitive demand. High-demand network activity may reflect the extent to which individuals require top-down executive guidance of behavior for successful task performance. Low-demand network activity may reflect task- and performance monitoring that minimizes executive requirements for guidance of behavior. PMID:20064942
Andersen, Barbara L.; Cyranowski, Jill M.
Classic and contemporary approaches to the assessment of female sexuality are discussed. General approaches, assessment strategies, and models of female sexuality are organized within the conceptual domains of sexual behaviors, sexual responses (desire, excitement, orgasm, and resolution), and individual differences, including general and sex-specific personality models. Where applicable, important trends and relationships are highlighted in the literature with both existing reports and previously unpublished data. The present conceptual overview highlights areas in sexual assessment and model building that are in need of further research and theoretical clarification. PMID:8543712
Orasanu, Judith; Fischer, Ute; Connors, Mary M. (Technical Monitor)
Team decision making involves contributions of multiple players toward a common goal. While much has been written about the importance of developing shared mental models in order for teams to work together effectively, little has been done to determine the value of alternative perspectives on problem solving and decision making. Early studies of expertise contrasted experts with novices and noted that the two groups differ in the way they structure problems and in their selection of information as salient. Little attention has been given to differences among experts who differ in their specializations. A series of experiments was conducted to determine: (1) what dimensions of flight-related problem situations pilots judge to be most important when making flight-relevant decisions; and (2) whether pilots in different crew positions differ in the way they interpret problems relating to flight decisions. A sorting task was used to identify underlying dimensions judged as salient to individual pilots. Captains, first officers, and flight engineers from two major carriers participated in the study. Twenty-two flight scenarios were developed based on ASRS reports. Pilots were required to make judgments about how they would respond in each case and to sort the scenarios on the basis of similarity of decision factors. They were also asked to provide a verbal label that described each of their sorted categories. A second study required a different group of pilots (also captains, first officers and flight engineers) to sort on predetermined bases.
Poole, Victoria N; Robinson, Meghan E; Singleton, Omar; DeGutis, Joseph; Milberg, William P; McGlinchey, Regina E; Salat, David H; Esterman, Michael
Distractor suppression, the ability to filter and ignore task-irrelevant information, is critical for efficient task performance. While successful distractor suppression relies on a balance of activity in neural networks responsible for attention maintenance (dorsal attention network; DAN), reorientation (ventral attention network; VAN), and internal thought (default mode network, DMN), the degree to which intrinsic connectivity within and between these networks contributes to individual differences in distractor suppression ability is not well-characterized. For the purposes of understanding these interactions, the current study collected resting-state fMRI data from 32 Veterans and, several months later (7±5 months apart), performance on the additional singleton paradigm, a measure of distractor suppression. Using multivariate support vector regression models composed of resting state connectivity between regions of the DAN, VAN, and DMN, and a leave-one-subject-out cross-validation procedure, we were able to predict an individual's task performance, yielding a significant correlation between the actual and predicted distractor suppression (r=0.48, p=0.0053). Network-level analyses revealed that greater within-network DMN connectivity was predictive of better distractor suppression, while greater connectivity between the DMN and attention networks was predictive of poorer distractor suppression. The strongest connection hubs were determined to be the right frontal eye field and temporoparietal junction of the DAN and VAN, respectively, and medial (ventromedial prefrontal and posterior cingulate cortices) and bilateral prefrontal regions of the DMN. These results are amongst a small but growing number of studies demonstrating that resting state connectivity is related to stable individual differences in cognitive ability, and suggest that greater integrity and independence of the DMN is related to better attentional ability.
Kreitz, Carina; Furley, Philip; Memmert, Daniel; Simons, Daniel J.
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
Murch, Kevin B; Krawczyk, Daniel C
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.
Fatima, Zainab; Kovacevic, Natasha; Misic, Bratislav; McIntosh, Anthony Randal
Current neuroscientific research has shown that the brain reconfigures its functional interactions at multiple timescales. Here, we sought to link transient changes in functional brain networks to individual differences in behavioral and cognitive performance by using an active learning paradigm. Participants learned associations between pairs of unrelated visual stimuli by using feedback. Interindividual behavioral variability was quantified with a learning rate measure. By using a multivariate statistical framework (partial least squares), we identified patterns of network organization across multiple temporal scales (within a trial, millisecond; across a learning session, minute) and linked these to the rate of change in behavioral performance (fast and slow). Results indicated that posterior network connectivity was present early in the trial for fast, and later in the trial for slow performers. In contrast, connectivity in an associative memory network (frontal, striatal, and medial temporal regions) occurred later in the trial for fast, and earlier for slow performers. Time-dependent changes in the posterior network were correlated with visual/spatial scores obtained from independent neuropsychological assessments, with fast learners performing better on visual/spatial subtests. No relationship was found between functional connectivity dynamics in the memory network and visual/spatial test scores indicative of cognitive skill. By using a comprehensive set of measures (behavioral, cognitive, and neurophysiological), we report that individual variations in learning-related performance change are supported by differences in cognitive ability and time-sensitive connectivity in functional neural networks. Hum Brain Mapp 37:3911-3928, 2016. © 2016 Wiley Periodicals, Inc.
Peltier, Chad; Becker, Mark W
Critical real-world visual search tasks such as radiology and baggage screening rely on the detection of rare targets. When targets are rare, observers search for a relatively short amount of time and have a high miss rate, a pattern of results known as the low prevalence effect. Attempts to improve the search for rare targets have been unsuccessful or resulted in an increase in detections at the price of more false alarms. As an alternative to improving visual search performance through experimental manipulations, an individual differences approach found that those with higher working memory capacity were better at finding rare targets. We build on the individual differences approach and assess 141 observers' visual working memory capacity (vWMC), vigilance, attentional control, big five personality traits, and performance in both high and low prevalence search tasks. vWMC, vigilance, attentional control, high prevalence visual search performance, and level of introversion were all significant predictors of low prevalence search accuracy, and together account for more than 50% of the variance in search performance. With the exception of vigilance, these factors are also significant predictors of reaction time; better performance was associated with longer reaction times, suggesting these factors identify observers who maintain relatively high quitting thresholds, even with low target prevalence. Our results suggest that a quick and easy-to-administer battery of tasks can identify observers who are likely to perform well in low prevalence search tasks, and these predictor variables are associated with higher quitting thresholds, leading to higher accuracy.
Kidd, Gary R.
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.
Gillioz, Christelle; Gygax, Pascal; Tapiero, Isabelle
This study investigated readers' representations of the main protagonist's emotional status in short narratives, as well as several mental factors that may affect these representations. General and visuospatial working memory, empathy, and simulation were investigated as potential individual differences in generating emotional inferences. Participants were confronted with narratives conveying information about the protagonist's emotional state. We manipulated each narrative's target sentence according to its content (emotional label vs. description of the behaviour associated to the emotion) and its congruence to the story (matching vs. mismatching). The results showed that globally the difference between reading times of congruent and incongruent target sentences was bigger in the behavioural than in the emotional condition. This pattern was accentuated for high visuospatial working memory participants when they were asked to simulate the stories. These results support the idea that mental models may be of a perceptual nature and may more likely include behavioural elements than emotion labels per se, as suggested earlier by Gygax et al. (2007).
Aksan, Nazan; Schall, Mark; Anderson, Steven; Dawson, Jeffery; Tippin, Jon; Rizzo, Matthew
Summary We examined the utility and validity of intermittent video samples from black box devices for capturing individual difference variability in real-world driving performance in an ongoing study of obstructive sleep apnea (OSA) and community controls. Three types of video clips were coded for several dimensions of interest to driving research including safety, exposure, and driver state. The preliminary findings indicated that clip types successfully captured variability along targeted dimensions such as highway vs. city driving, driver state such as distraction and sleepiness, and safety. Sleepiness metrics were meaningfully associated with adherence to PAP (positive airway pressure) therapy. OSA patients who were PAP adherent showed less sleepiness and less non-driving related gaze movements than nonadherent patients. Simple differences in sleepiness did not readily translate to improvements in driver safety, consistent with epidemiologic evidence to date. PMID:24535569
Yamamoto, Kohsuke; Toyota, Hiroshi
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.
Bieniek, Magdalena M.; Frei, Luisa S.; Rousselet, Guillaume A.
Recently, Rousselet et al. reported a 1 ms/year delay in visual processing speed in a sample of healthy aged 62 subjects (Frontiers in Psychology 2010, 1:19). Here, we replicate this finding in an independent sample of 59 subjects and investigate the contribution of optical factors (pupil size and luminance) to the age-related slowdown and to individual differences in visual processing speed. We conducted two experiments. In experiment 1 we recorded EEG from subjects aged 18–79. Subjects viewed images of faces and phase scrambled noise textures under nine luminance conditions, ranging from 0.59 to 60.8 cd/m2. We manipulated luminance using neutral density filters. In experiment 2, 10 young subjects (age < 35) viewed similar stimuli through pinholes ranging from 1 to 5 mm. In both experiments, subjects were tested twice. We found a 1 ms/year slowdown in visual processing that was independent of luminance. Aging effects became visible around 125 ms post-stimulus and did not affect the onsets of the face-texture ERP differences. Furthermore, luminance modulated the entire ERP time-course from 60 to 500 ms. Luminance effects peaked in the N170 time window and were independent of age. Importantly, senile miosis and individual differences in pupil size did not account for aging differences and inter-subject variability in processing speed. The pinhole manipulation also failed to match the ERPs of old subjects to those of young subjects. Overall, our results strongly suggest that early ERPs to faces (<200 ms) are delayed by aging and that these delays are of cortical, rather than optical origin. Our results also demonstrate that even late ERPs to faces are modulated by low-level factors. PMID:23717297
Jagadeesh, Anoop; Mauermann, Manfred; Ernst, Frauke
Little is known about how outer hair cell loss interacts with noise-induced and age-related auditory nerve degradation (i.e., cochlear synaptopathy) to affect auditory brainstem response (ABR) wave characteristics. Given that listeners with impaired audiograms likely suffer from mixtures of these hearing deficits and that ABR amplitudes have successfully been used to isolate synaptopathy in listeners with normal audiograms, an improved understanding of how different hearing pathologies affect the ABR source generators will improve their sensitivity in hearing diagnostics. We employed a functional model for human ABRs in which different combinations of hearing deficits were simulated and show that high-frequency cochlear gain loss steepens the slope of the ABR Wave-V latency versus intensity and amplitude versus intensity curves. We propose that grouping listeners according to a ratio of these slope metrics (i.e., the ABR growth ratio) might offer a way to factor out the outer hair cell loss deficit and maximally relate individual differences for constant ratios to other peripheral hearing deficits such as cochlear synaptopathy. We compared the model predictions to recorded click-ABRs from 30 participants with normal or high-frequency sloping audiograms and confirm the predicted relationship between the ABR latency growth curve and audiogram slope. Experimental ABR amplitude growth showed large individual differences and was compared with the Wave-I amplitude, Wave-V/I ratio, or the interwaveI–W latency in the same listeners. The model simulations along with the ABR recordings suggest that a hearing loss profile depicting the ABR growth ratio versus the Wave-I amplitude or Wave-V/I ratio might be able to differentiate outer hair cell deficits from cochlear synaptopathy in listeners with mixed pathologies. PMID:27837052
Shumake, Jason; Furgeson-Moreira, Sergio; Monfils, Marie H
Our objective was to characterize individual differences in fear conditioning and extinction in an outbred rat strain, to test behavioral predictors of these individual differences, and to assess their heritability. We fear-conditioned 100 Long-Evans rats, attempted to extinguish fear the next day, and tested extinction recall on the third day. The distribution of freezing scores after fear conditioning was skewed, with most rats showing substantial freezing; after fear extinction, the distribution was bimodal with most rats showing minimal freezing, but a substantial portion showing maximal freezing. Longer rearing episodes measured prior to conditioning predicted less freezing at the beginning of extinction, but differences in extinction learning were not predicted by any baseline exploratory behaviors. We tested the heritability of extinction differences by breeding rats from the top and bottom 20% of freezing scores during extinction recall. We then ran the offspring through the same conditioning/extinction procedure, with the addition of recording ultrasonic vocalizations throughout training and testing. Only a minority of rats emitted distress vocalizations during fear acquisition, but the incidence was less frequent in the offspring of good extinguishers than in poor extinguishers or randomly bred controls. The occurrence of distress vocalizations during acquisition predicted higher levels of freezing during fear recall regardless of breeding line, but the relationship between vocalization and freezing was no longer evident following extinction training, at which point freezing levels were influenced only by breeding and not by vocalization. The heritability (h(2)) of extinction recall was estimated at 0.36, consistent with human estimates.
Travis, Frederick T.; Wallace, Robert Keith
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. PMID:26834428
Grabner, Roland H; Ansari, Daniel; Reishofer, Gernot; Stern, Elsbeth; Ebner, Franz; Neuper, Christa
Functional neuroimaging studies have revealed that parietal brain circuits subserve arithmetic problem solving and that their recruitment dynamically changes as a function of training and development. The present study investigated whether the brain activation during mental calculation is also modulated by individual differences in mathematical competence. Twenty-five adult students were selected from a larger pool based on their performance on standardized tests of intelligence and arithmetic and divided into groups of individuals with relatively lower and higher mathematical competence. These groups did not differ in their non-numerical intelligence or age. In an fMRI block-design, participants had to verify the correctness of single-digit and multi-digit multiplication problems. Analyses revealed that the individuals with higher mathematical competence displayed stronger activation of the left angular gyrus while solving both types of arithmetic problems. Additional correlational analyses corroborated the association between individual differences in mathematical competence and angular gyrus activation, even when variability in task performance was controlled for. These findings demonstrate that the recruitment of the left angular gyrus during arithmetic problem solving underlies individual differences in mathematical ability and suggests a stronger reliance on automatic, language-mediated processes in more competent individuals.
Chang, Ting-Yun; Yang, Cheng-Ta
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 non-parametric 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. PMID:25477842
Cullen, Harriet; Kanai, Ryota; Bahrami, Bahador; Rees, Geraint
Anthropomorphism is the attribution of human characteristics or behaviour to animals, non-living things or natural phenomena. It is pervasive among humans, yet nonetheless exhibits a high degree of inter-individual variability. We hypothesized that brain areas associated with anthropomorphic thinking might be similar to those engaged in the attribution of mental states to other humans, the so-called 'theory of mind' or mentalizing network. To test this hypothesis, we related brain structure measured using magnetic resonance imaging in a sample of 83 healthy young adults to a simple, self-report questionnaire that measured the extent to which our participants made anthropomorphic attributions about non-human animals and non-animal stimuli. We found that individual differences in anthropomorphism for non-human animals correlated with the grey matter volume of the left temporoparietal junction, a brain area involved in mentalizing. Our data support previous work indicating a link between areas of the brain involved in attributing mental states to other humans and those involved in anthropomorphism.
de Bézenac, Christophe E; Sluming, Vanessa; O'Sullivan, Noreen; Corcoran, Rhiannon
Individuals differ in their ability to attribute actions to self or other. This variance is thought to explain, in part, the experience of voice-hearing. Misattribution can also be context-driven. For example, causal ambiguity can arise when the actions of two or more individuals are coordinated and produce similar effects (e.g., music-making). Experience in such challenging contexts may refine skills of action attribution. Forty participants completed a novel finger-tapping task which parametrically manipulated the proportion of control that 'self' versus 'other' possessed over resulting auditory tones. Results showed that action misattribution peaked in the middle of the self-to-other continuum and was biased towards other. This pattern was related to both high hallucination-proneness and to low musical-experience. Findings suggest not only that causal ambiguity plays a key role in agency but also that action attribution abilities may improve with practice, potentially providing an avenue for remediation of the positive symptoms of schizophrenia.
Kanai, Ryota; Bahrami, Bahador; Rees, Geraint
Anthropomorphism is the attribution of human characteristics or behaviour to animals, non-living things or natural phenomena. It is pervasive among humans, yet nonetheless exhibits a high degree of inter-individual variability. We hypothesized that brain areas associated with anthropomorphic thinking might be similar to those engaged in the attribution of mental states to other humans, the so-called ‘theory of mind’ or mentalizing network. To test this hypothesis, we related brain structure measured using magnetic resonance imaging in a sample of 83 healthy young adults to a simple, self-report questionnaire that measured the extent to which our participants made anthropomorphic attributions about non-human animals and non-animal stimuli. We found that individual differences in anthropomorphism for non-human animals correlated with the grey matter volume of the left temporoparietal junction, a brain area involved in mentalizing. Our data support previous work indicating a link between areas of the brain involved in attributing mental states to other humans and those involved in anthropomorphism. PMID:23887807
Ueda, Ryuhei; Ashida, Hiroshi; Yanagisawa, Kuniaki; Abe, Nobuhito
This study tested the hypothesis that individual differences in the activity of the orbitofrontal cortex, a region implicated in value-based decision-making, are associated with the preference for a person with a partner, which could lead to mate poaching. During functional magnetic resonance imaging (fMRI), male participants were presented with facial photographs of (a) attractive females with a partner, (b) attractive females without a partner, (c) unattractive females with a partner, and (d) unattractive females without a partner. The participants were asked to rate the degree to which they desired a romantic relationship with each female using an 8-point scale. The participants rated attractive females higher than unattractive females, and this effect was associated with ventral striatum activation. The participants also indicated lower ratings for females with a partner than for females without a partner, and this effect was associated with parietal cortex activation. As predicted, the participants characterized by higher orbitofrontal activity demonstrated a greater willingness to engage in a romantic relationship with females who have a partner compared with females who do not have a partner. These results are the first to provide a possible neural explanation for why certain individuals are willing to engage in mate poaching.
Miu, Andrei C
The methodological and empirical development of cognitive, affective and clinical neuroscience has brought these fields into the ideal position of being able to benefit from the increasing number of techniques and interdisciplinary applications developed since the completion of the sequencing of the human genome. An increasingly investigated topic in behavioral, molecular and neuroimaging genetics concerns genetic influences on emotional reactivity and regulation. The estimation of the heritability of emotional traits and states, and the identification of functional genetic polymorphisms that are associated with emotional aspects of behavior, hold great promise for understanding the etiology and pathogenesis of mood and anxiety disorders. This article briefly reviews evidence from twin, genetic association, and neuroimaging genetic studies of individual differences in emotion reactivity and regulation, with an emphasis on trends in recent research, and their potential to contribute to the clinical neuroscience of emotional dysfunction.
Salmond, C H; de Haan, M; Friston, K J; Gadian, D G; Vargha-Khadem, F
Autism is a psychiatric syndrome characterized by impairments in three domains: social interaction, communication, and restricted and repetitive behaviours and interests. Recent findings implicate the amygdala in the neurobiology of autism. In this paper, we report the results of a series of novel experimental investigations focusing on the structure and function of the amygdala in a group of children with autism. The first section attempts to determine if abnormality of the amygdala can be identified in an individual using magnetic resonance imaging in vivo. Using single-case voxel-based morphometric analyses, abnormality in the amygdala was detected in half the children with autism. Abnormalities in other regions were also found. In the second section, emotional modulation of the startle response was investigated in the group of autistic children. Surprisingly, there were no significant differences between the patterns of emotional modulation of the startle response in the autistic group compared with the controls. PMID:12639337
König, Susanne; Glück, Judith
Previous research has shown that most laypeople hold one of two typical conceptions of wisdom--a cognitive or an integrative conception. The current study extends previous research by including a qualitative assessment of people's views of what wisdom is and how it develops, and by relating wisdom conceptions are related to levels of wisdom and gratitude. A sample of 443 young adults rated the relevance of cognitive, reflective, and affective aspects for wisdom. Cluster analyses confirmed the two typical wisdom conceptions: a primarily cognitive view of wisdom and a view emphasizing the integration of cognition, reflection, and affect. The two groups also differed in freely-generated characteristics of wisdom and its development. Additionally, the integrative conception was more frequent in individuals with higher levels of gratitude and wisdom. In sum, laypeople's conceptions of wisdom vary along similar lines as those of wisdom psychologists.
Vukovic, Rose K; Fuchs, Lynn S; Geary, David C; Jordan, Nancy C; Gersten, Russell; Siegler, Robert S
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 knowledge) competencies; at 7 years on whole-number arithmetic computations and number line estimation; and at 10 years on fraction concepts. Mediation analyses controlling for general mathematics ability and general academic ability revealed that numerical and mathematical competencies were direct predictors of fraction concepts, whereas domain-general competencies supported the acquisition of fraction concepts via whole-number arithmetic computations or number line estimation. Results indicate multiple pathways to fraction competence.
Blake, Christine E.
Individual differences in food-related knowledge structures were explored by applying schema theory to examine the categories 42 adults used to classify foods across four eating contexts. Food card-sort labels were organized into 12 categories, category salience for each person was evaluated, and cluster analysis was used to identify clusters of participants according to the salience of their categories. Clusters were further evaluated for complexity and consistency of category use across contexts. Seven food schema clusters were identified. Meal/time and Routine categories were the most salient overall and were used by most clusters. Well-being, Person, Source, Convenience, Meal component, and Food group categories varied in salience across clusters. The complexity and consistency of the food categories participants used across the contexts varied among the clusters. This study provided insight about cognitions that may underlie food-choice behaviors. Understanding individuals’ food schemas could help nutrition professionals tailor messages to maximize health impact. PMID:19122739
Arnold, Kathleen M; McDermott, Kathleen B; Szpunar, Karl K
Tulving (1985) posited that the capacity to remember is one facet of a more general capacity-autonoetic (self-knowing) consciousness. Autonoetic consciousness was proposed to underlie the ability for "mental time travel" both into the past (remembering) and into the future to envision potential future episodes (episodic future thinking). The current study examines whether individual differences can predict autonoetic experience. Specifically, the Zimbardo Time Perspective Inventory (ZTPI, Zimbardo & Boyd, 1999) was administered to 133 undergraduate students, who also rated phenomenological experiences accompanying autobiographical remembering and episodic future thinking. Scores on two of the five subscales of the ZTPI (Future and Present-Hedonistic) predicted the degree to which people reported feelings of mentally traveling backward (or forward) in time and the degree to which they reported re- or pre-experiencing the event, but not ten other rated properties less related to autonoetic consciousness.
Kalanthroff, E; Henik, A
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.
Kaye, Sherrie-Anne; White, Melanie J; Lewis, Ioni M
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
Aczel, Balazs; Bago, Bence; Szollosi, Aba; Foldes, Andrei; Lukacs, Bence
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. PMID:26635677
An important contributor to the differences between individuals derives from their plasticity. Such plasticity is widespread in organisms from the simple to the most complex. Adaptability plasticity enables the organism to cope with a novel challenge not previously encountered by its ancestors. Conditional plasticity appears to have evolved from repeated challenges from the environment so that the organism responds in a particular manner to the environment in which it finds itself. The resulting phenotypic variation can be triggered during development in a variety of ways, some mediated through the parent's phenotype. Sometimes the organism copes in suboptimal conditions trading off reproductive success against survival. Whatever the adaptedness of the phenotype, each of the many types of plasticity demonstrates how a given genotype will express itself differently in different environmental conditions—a field of biology referred to as the study of epigenetics. The ways in which epigenetic mechanisms may have evolved are discussed, as are the potential impacts on the evolution of their descendants. PMID:25407080
Nijhof, Annabel D; Willems, Roel M
When we read literary fiction, we are transported to fictional places, and we feel and think along with the characters. Despite the importance of narrative in adult life and during development, the neurocognitive mechanisms underlying fiction comprehension are unclear. We used functional magnetic resonance imaging (fMRI) to investigate how individuals differently employ neural networks important for understanding others' beliefs and intentions (mentalizing), and for sensori-motor simulation while listening to excerpts from literary novels. Localizer tasks were used to localize both the cortical motor network and the mentalizing network in participants after they listened to excerpts from literary novels. Results show that participants who had high activation in anterior medial prefrontal cortex (aMPFC; part of the mentalizing network) when listening to mentalizing content of literary fiction, had lower motor cortex activity when they listened to action-related content of the story, and vice versa. This qualifies how people differ in their engagement with fiction: some people are mostly drawn into a story by mentalizing about the thoughts and beliefs of others, whereas others engage in literature by simulating more concrete events such as actions. This study provides on-line neural evidence for the existence of qualitatively different styles of moving into literary worlds, and adds to a growing body of literature showing the potential to study narrative comprehension with neuroimaging methods.
Joseph, Paule Valery; Reed, Danielle R.; Mennella, Julie A.
Background Little research has focused on whether there are individual differences among children in their sensitivity to sweet taste and, if so, the biological correlates of such differences. Objectives Our goal was to understand how variations in children’s sucrose detection thresholds relate to their age and gender, taste genotype, body composition, and dietary intake of added sugars. Methods Sucrose detection thresholds in 7- to 14-year-old children were tested individually using a validated, two-alternative, forced-choice, paired-comparison tracking method. Five genetic variants of taste genes were assayed: TAS1R3 and GNAT3 (sweet genes; one variant each) and the bitter receptor gene TAS2R38 (three variants). All children were measured for body weight and height. A subset of these children were measured for the percentage of body fat and waist circumference and provided added sugar intake by 24-hour dietary recall. Results Sucrose thresholds ranged from 0.23 to 153.8 mM with most of the children completing the threshold task (216/235; 92%). Some children were biologically related (i.e., siblings), and for the genetic analysis, one sibling from each family was studied. Variants in the bitter but not the sweet genes were related to sucrose threshold and sugar intake; children with two bitter-sensitive alleles could detect sucrose at lower concentrations (F(2,165) = 4.55, p = .01; rs1726866) and reported eating more added sugar (% kcal; F(2, 62) = 3.64, p = .03) than did children with less sensitive alleles. Age, gender, and indices of obesity also were related to child-to-child differences in sucrose threshold; girls were more sensitive than boys (t(214) = 2.0, p = .05), older children were more sensitive than younger children (r(214) = −.16, p = .02), and fatter (r(84) = −.22, p = .05) or more centrally obese children (r(84) = −.26, p = .02) were more sensitive relative to others. Discussion Inborn differences in bitter sensitivity may affect childhood
... 40 Protection of Environment 26 2013-07-01 2013-07-01 false Are the Individual Protection and Ground Water Protection Standards Severable? 197.38 Section 197.38 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) RADIATION PROTECTION PROGRAMS PUBLIC HEALTH AND...
... 40 Protection of Environment 25 2014-07-01 2014-07-01 false Are the Individual Protection and Ground Water Protection Standards Severable? 197.38 Section 197.38 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) RADIATION PROTECTION PROGRAMS PUBLIC HEALTH AND...
... 40 Protection of Environment 26 2012-07-01 2011-07-01 true Are the Individual Protection and Ground Water Protection Standards Severable? 197.38 Section 197.38 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) RADIATION PROTECTION PROGRAMS PUBLIC HEALTH AND...
... 10 Energy 2 2014-01-01 2014-01-01 false Severability of individual protection and ground-water protection standards. 63.343 Section 63.343 Energy NUCLEAR REGULATORY COMMISSION (CONTINUED) DISPOSAL OF HIGH-LEVEL RADIOACTIVE WASTES IN A GEOLOGIC REPOSITORY AT YUCCA MOUNTAIN, NEVADA Postclosure Public...
... 10 Energy 2 2010-01-01 2010-01-01 false Severability of individual protection and ground-water protection standards. 63.343 Section 63.343 Energy NUCLEAR REGULATORY COMMISSION (CONTINUED) DISPOSAL OF HIGH-LEVEL RADIOACTIVE WASTES IN A GEOLOGIC REPOSITORY AT YUCCA MOUNTAIN, NEVADA Postclosure Public...
... 10 Energy 2 2012-01-01 2012-01-01 false Severability of individual protection and ground-water protection standards. 63.343 Section 63.343 Energy NUCLEAR REGULATORY COMMISSION (CONTINUED) DISPOSAL OF HIGH-LEVEL RADIOACTIVE WASTES IN A GEOLOGIC REPOSITORY AT YUCCA MOUNTAIN, NEVADA Postclosure Public...
... 10 Energy 2 2013-01-01 2013-01-01 false Severability of individual protection and ground-water protection standards. 63.343 Section 63.343 Energy NUCLEAR REGULATORY COMMISSION (CONTINUED) DISPOSAL OF HIGH-LEVEL RADIOACTIVE WASTES IN A GEOLOGIC REPOSITORY AT YUCCA MOUNTAIN, NEVADA Postclosure Public...
... 10 Energy 2 2011-01-01 2011-01-01 false Severability of individual protection and ground-water protection standards. 63.343 Section 63.343 Energy NUCLEAR REGULATORY COMMISSION (CONTINUED) DISPOSAL OF HIGH-LEVEL RADIOACTIVE WASTES IN A GEOLOGIC REPOSITORY AT YUCCA MOUNTAIN, NEVADA Postclosure Public...
... 12 Banks and Banking 1 2013-01-01 2013-01-01 false Standards for determination of appropriate individual minimum capital ratios. 3.11 Section 3.11 Banks and Banking COMPTROLLER OF THE CURRENCY... necessary for the bank; (b) The exigency of those circumstances or potential problems; (c) The...
... 12 Banks and Banking 1 2011-01-01 2011-01-01 false Standards for determination of appropriate individual minimum capital ratios. 3.11 Section 3.11 Banks and Banking COMPTROLLER OF THE CURRENCY... necessary for the bank; (b) The exigency of those circumstances or potential problems; (c) The...
.../or affiliate(s); (d) The bank's liquidity, capital, risk asset and other ratios compared to the... 12 Banks and Banking 1 2010-01-01 2010-01-01 false Standards for determination of appropriate individual minimum capital ratios. 3.11 Section 3.11 Banks and Banking COMPTROLLER OF THE...
... drain systems. 60.693-1 Section 60.693-1 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY... Performance for VOC Emissions From Petroleum Refinery Wastewater Systems § 60.693-1 Alternative standards for individual drain systems. (a) An owner or operator may elect to construct and operate a completely...
... drain systems. 60.693-1 Section 60.693-1 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY... Performance for VOC Emissions From Petroleum Refinery Wastewater Systems § 60.693-1 Alternative standards for individual drain systems. (a) An owner or operator may elect to construct and operate a completely...
... drain systems. 60.693-1 Section 60.693-1 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY... Performance for VOC Emissions From Petroleum Refinery Wastewater Systems § 60.693-1 Alternative standards for individual drain systems. (a) An owner or operator may elect to construct and operate a completely...
Hahn, Carole J.; Rossow, William B.; Warren, Stephen G.
Individual surface weather observations from land stations and ships are compared with individual cloud retrievals of the International Satellite Cloud Climatology Project (ISCCP), Stage C1, for an 8-year period (1983-1991) to relate cloud optical thicknesses and cloud-top pressures obtained from satellite data to the standard cloud types reported in visual observations from the surface. Each surface report is matched to the corresponding ISCCP-C1 report for the time of observation for the 280x280-km grid-box containing that observation. Classes of the surface reports are identified in which a particular cloud type was reported present, either alone or in combination with other clouds. For each class, cloud amounts from both surface and C1 data, base heights from surface data, and the frequency-distributions of cloud-top pressure (p(sub c) and optical thickness (tau) from C1 data are averaged over 15-degree latitude zones, for land and ocean separately, for 3-month seasons. The frequency distribution of p(sub c) and tau is plotted for each of the surface-defined cloud types occurring both alone and with other clouds. The average cloud-top pressures within a grid-box do not always correspond well with values expected for a reported cloud type, particularly for the higher clouds Ci, Ac, and Cb. In many cases this is because the satellites also detect clouds within the grid-box that are outside the field of view of the surface observer. The highest average cloud tops are found for the most extensive cloud type, Ns, averaging 7 km globally and reaching 9 km in the ITCZ. Ns also has the greatest average retrieved optical thickness, tau approximately equal 20. Cumulonimbus clouds may actually attain far greater heights and depths, but do not fill the grid-box. The tau-p(sub c) distributions show features that distinguish the high, middle, and low clouds reported by the surface observers. However, the distribution patterns for the individual low cloud types (Cu, Sc, St
Jaeggi, Susanne M; Buschkuehl, Martin; Shah, Priti; Jonides, John
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.
Girard, T A; Cheyne, J A
Individual differences were investigated in the lateralisation of two general categories of hypnagogic and hypnopompic hallucinations associated with sleep paralysis: (1) Vestibular-motor (V-M) hallucinations; comprising sensations of floating, flying, illusory locomotion and postural adjustments, out-of-body experiences (OBE), and autoscopy; and (2) Intruder hallucinations; incorporating a sense of the presence, and visual and auditory hallucinations of external, alien agents. Left-right lateralisation of such hallucinations, as well as handedness and footedness, were assessed in a diverse, nonclinical sample of 201 subjects participating in a web-based survey of sleep paralysis experiences. V-M hallucinations, but not Intruder hallucinations were predicted, based on the hypothesised distinctive neural sources of the different hallucinations, to be positively associated with handedness and footedness. Specifically, the predictions were based on the hypothesis that the activation of components of a vestibular, motor, and kinaesthetic bodily-self neuromatrix underlies V-M hallucinations, whereas a threat-activated vigilance system is responsible for Intruder hallucinations. As predicted, limb preferences were consistently found to be significantly and positively associated with a side bias of V-M, but not Intruder, hallucinations.
Ratcliff, Roger; Thompson, Clarissa A; McKoon, Gail
In the study of numeracy, some hypotheses have been based on response time (RT) as a dependent variable and some on accuracy, and considerable controversy has arisen about the presence or absence of correlations between RT and accuracy, between RT or accuracy and individual differences like IQ and math ability, and between various numeracy tasks. In this article, we show that an integration of the two dependent variables is required, which we accomplish with a theory-based model of decision making. We report data from four tasks: numerosity discrimination, number discrimination, memory for two-digit numbers, and memory for three-digit numbers. Accuracy correlated across tasks, as did RTs. However, the negative correlations that might be expected between RT and accuracy were not obtained; if a subject was accurate, it did not mean that they were fast (and vice versa). When the diffusion decision-making model was applied to the data (Ratcliff, 1978), we found significant correlations across the tasks between the quality of the numeracy information (drift rate) driving the decision process and between the speed/accuracy criterion settings, suggesting that similar numeracy skills and similar speed-accuracy settings are involved in the four tasks. In the model, accuracy is related to drift rate and RT is related to speed-accuracy criteria, but drift rate and criteria are not related to each other across subjects. This provides a theoretical basis for understanding why negative correlations were not obtained between accuracy and RT. We also manipulated criteria by instructing subjects to maximize either speed or accuracy, but still found correlations between the criteria settings between and within tasks, suggesting that the settings may represent an individual trait that can be modulated but not equated across subjects. Our results demonstrate that a decision-making model may provide a way to reconcile inconsistent and sometimes contradictory results in numeracy
Meyer, Alexandria; Lerner, Matthew D; De Los Reyes, Andres; Laird, Robert D; Hajcak, Greg
There is growing interest in psychophysiological and neural correlates of psychopathology, personality, and other individual differences. Many studies correlate a criterion individual difference variable (e.g., anxiety) with a psychophysiological measurement derived by subtracting scores taken from two within-subject conditions. These subtraction-based difference scores are intended to increase specificity by isolating variability of interest. Using data on the error-related negativity (ERN) and correct response negativity (CRN) in relation to generalized anxiety disorder (GAD), we highlight several conceptual and practical issues with subtraction-based difference scores and propose alternative approaches based on regression. We show that ERN and CRN are highly correlated, and that the ΔERN (i.e., ERN - CRN) is correlated in opposite directions both with ERN and CRN. Bivariate analyses indicate that GAD is related to ΔERN and ERN, but not CRN. We first show that, by using residualized scores, GAD relates both to a larger ERN and smaller CRN. Moreover, by probing the interaction of ERN and CRN, we show that the relationship between GAD and ERN varies by CRN. These latter findings are not evident when using traditional subtraction-based difference scores. We then completed follow-up analyses that suggested that an increased P300 in anxious individuals gave rise to the apparent anxiety/CRN relationship observed. These findings have important conceptual implications for facilitating the interpretability of results from individual difference studies of psychophysiology.
Bonin, Patrick; Méot, Alain; Millotte, Séverine; Barry, Christopher
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.
Schertz, Jessamyn; Cho, Taehong; Lotto, Andrew; Warner, Natasha
Listeners possess a remarkable ability to adapt to acoustic variability in the realization of speech sound categories (e.g., different accents). The current work tests whether non-native listeners adapt their use of acoustic cues in phonetic categorization when they are confronted with changes in the distribution of cues in the input, as native listeners do, and examines to what extent these adaptation patterns are influenced by individual cue-weighting strategies. In line with previous work, native English listeners, who use voice onset time (VOT) as a primary cue to the stop voicing contrast (e.g., 'pa' vs. 'ba'), adjusted their use of f0 (a secondary cue to the contrast) when confronted with a noncanonical "accent" in which the two cues gave conflicting information about category membership. Native Korean listeners' adaptation strategies, while variable, were predictable based on their initial cue weighting strategies. In particular, listeners who used f0 as the primary cue to category membership adjusted their use of VOT (their secondary cue) in response to the noncanonical accent, mirroring the native pattern of "downweighting" a secondary cue. Results suggest that non-native listeners show native-like sensitivity to distributional information in the input and use this information to adjust categorization, just as native listeners do, with the specific trajectory of category adaptation governed by initial cue-weighting strategies.
Healey, M. Karl; Crutchley, Patrick; Kahana, Michael J.
Attempts to understand why memory predicts intelligence have not fully leveraged state-of-the-art measures of recall dynamics. Using data from a multi–session free recall study we examine individual differences in measures of recall initiation and post–initiation transitions. We identify four sources of variation: a recency factor reflecting variation in the tendency to initiate recall from an item near the end of the list, a primacy factor reflecting a tendency to initiate from the beginning of the list, a temporal factor corresponding to transitions mediated by temporal associations, and a semantic factor corresponding to semantically–mediated transitions. Together these four factors account for 83% of the variability in overall recall accuracy, suggesting they provide a nearly complete picture of recall dynamics. We also show that these sources of variability account for over 80% of the variance shared between memory and intelligence. The temporal association factor was the most influential in predicting both recall accuracy and intelligence. We outline a theory of how controlled drift of temporal context may be critical across a range of cognitive activities. PMID:24730719
Schertz, Jessamyn; Cho, Taehong; Lotto, Andrew; Warner, Natasha
Listeners possess a remarkable ability to adapt to acoustic variability in the realization of speech sound categories (e.g. different accents). The current work tests whether non-native listeners adapt their use of acoustic cues in phonetic categorization when they are confronted with changes in the distribution of cues in the input, as native listeners do, and examines to what extent these adaptation patterns are influenced by individual cue-weighting strategies. In line with previous work, native English listeners, who use VOT as a primary cue to the stop voicing contrast (e.g. ‘pa’ vs. ‘ba’), adjusted their use of f0 (a secondary cue to the contrast) when confronted with a noncanonical “accent” in which the two cues gave conflicting information about category membership. Native Korean listeners’ adaptation strategies, while variable, were predictable based on their initial cue weighting strategies. In particular, listeners who used f0 as the primary cue to category membership adjusted their use of VOT (their secondary cue) in response to the noncanonical accent, mirroring the native pattern of “downweighting” a secondary cue. Results suggest that non-native listeners show native-like sensitivity to distributional information in the input and use this information to adjust categorization, just as native listeners do, with the specific trajectory of category adaptation governed by initial cue-weighting strategies. PMID:26404530
Geva, E; Yaghoub-Zadeh, Z; Schuster, B
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.
RATCLIFF, ROGER; THAPAR, ANJALI; McKOON, GAIL
The effects of aging on performance were examined in signal detection, letter discrimination, brightness discrimination, and recognition memory, with each subject tested on all four tasks. Ratcliff's (1978) diffusion model was fit to the data for each subject for each task, and it provided a good account of accuracy and the distributions of correct and error response times. the model's analysis of the components of processing showed that aging had three main effects: the nondecision components of processing were slower and the decision criteria were more conservative for 60- to 74-year-old and 75- to 85-year-old subjects than for college students, but the quality of the evidence on which decisions were based was as good for the older subjects as for college students on some of the tasks. individual differences among subjects in components of processing tended to be preserved across the tasks, as was shown by strong correlations across the tasks in the parameters of the model that represent the components of processing. for example, if the evidence on which a subject's decisions were based was good in one task, it tended to be good in all four tasks. PMID:17201362
Haynos, Ann F.; Snipes, Cassandra; Guarda, Angela; Mayer, Laurel E.; Attia, Evelyn
Objective Sparse research informs how caloric prescriptions should be advanced during nutritional rehabilitation of inpatients with anorexia nervosa (AN). This study compared the impact of a standardized caloric increase approach, in which increases occurred on a predetermined schedule, to an individualized approach, in which increases occurred only following insufficient weight gain, on rate, pattern, and cumulative amount of weight gain and other weight restoration outcomes. Method This study followed a natural experiment design comparing AN inpatients consecutively admitted before (n = 35) and after (n = 35) an institutional change from individualized to standardized caloric prescriptions. Authors examined the impact of prescription plan on weekly weight gain in the first treatment month using multilevel modeling. Within a subsample remaining inpatient through weight restoration (n = 40), multiple regressions examined the impact of caloric prescription plan on time to weight restoration, length of hospitalization, maximum caloric prescription, discharge BMI, and incidence of activity restriction and edema. Results There were significant interactions between prescription plan and quadratic time on average weekly weight gain (p = .03) and linear time on cumulative weekly weight gain (p < .001). Under the standardized plan, patients gained in an accelerated curvilinear pattern (p = .04) and, therefore, gained cumulatively greater amounts of weight over time (p < .001). Additionally, 30% fewer patients required activity restriction under the standardized plan. Discussion Standardized caloric prescriptions may confer advantage by facilitating accelerated early weight gain and lower incidence of bed rest without increasing the incidence of refeeding syndrome. PMID:26769581
Engelhardt, Paul E; Nigg, Joel T; Ferreira, Fernanda
There has been little research on the fluency of language production and individual difference variables, such as intelligence and executive function. In this study, we report data from 106 participants who completed a battery of standardized cognitive tasks and a sentence production task. For the sentence production task, participants were presented with two objects and a verb and their task was to formulate a sentence. Four types of disfluency were examined: filled pauses (e.g. uh, um), unfilled pauses, repetitions, and repairs. Repetitions occur when the speaker suspends articulation and then repeats the previous word/phrase, and repairs occur when the speaker suspends articulation and then starts over with a different word/phrase. Hierarchical structural equation modeling revealed a significant relationship between repair disfluencies and inhibition. Conclusions focus on the role of individual differences in cognitive ability and their role in models and theories of language production.
Kolayli, Sevgi; Kara, Meryem; Tezcan, Filiz; Erim, F Bedia; Sahin, Huseyin; Ulusoy, Esra; Aliyazicioglu, Rezzan
Chemical and biochemical properties of standard, hybrid, and grafted melons cultivated under the same agricultural conditions in adjacent fields in the Cumra region of Turkey were investigated and compared based on pH, Brix, antioxidant activity, total phenolics, ascorbic acid, individual phenolics, sugar, and organic acid values. Seventeen different phenolic constituents were quantified by reverse phase high-performance liquid chromatography (RP-HPLC). The highest phenolic acid variability and content were detected in the standard melon. Sugar and organic acid compositions of melon cultivars were tested by capillary electrophoresis, and significant differences in types and contents of individual sugars and organic acids were determined among the cultivars. Standard Cinikiz Cumra melons had the highest ascorbic acid, total phenolics, and total sugar contents. The fructose/glucose ratio increased three times in grafted melon as compared with standard melon. While sugar alcohol mannitol existed in the standard and hybrid cultivars, this constituent disappeared in the grafted types. Citric acid found in the standard cultivar was not detected in the hybrid and grafted types. Consequently, it was concluded that the nutritional value of melons changed by the application of hybridization, grafting, or standard (open pollinated) production methods. The standard melon was found to have the highest score in terms of taste, because of its highest sweetness and sourness. It was also found preferable because of its high antioxidant activity, total phenolic and ascorbic acid contents.
Cecere, Roberto; Rees, Geraint; Romei, Vincenzo
Perception routinely integrates inputs from different senses. Stimulus temporal proximity critically determines whether or not these inputs are bound together. Despite the temporal window of integration being a widely accepted notion, its neurophysiological substrate remains unclear. Many types of common audio-visual interactions occur within a time window of ∼100 ms. For example, in the sound-induced double-flash illusion, when two beeps are presented within ∼100 ms together with one flash, a second illusory flash is often perceived. Due to their intrinsic rhythmic nature, brain oscillations are one candidate mechanism for gating the temporal window of integration. Interestingly, occipital alpha band oscillations cycle on average every ∼100 ms, with peak frequencies ranging between 8 and 14 Hz (i.e., 120-60 ms cycle). Moreover, presenting a brief tone can phase-reset such oscillations in visual cortex. Based on these observations, we hypothesized that the duration of each alpha cycle might provide the temporal unit to bind audio-visual events. Here, we first recorded EEG while participants performed the sound-induced double-flash illusion task and found positive correlation between individual alpha frequency (IAF) peak and the size of the temporal window of the illusion. Participants then performed the same task while receiving occipital transcranial alternating current stimulation (tACS), to modulate oscillatory activity either at their IAF or at off-peak alpha frequencies (IAF±2 Hz). Compared to IAF tACS, IAF-2 Hz and IAF+2 Hz tACS, respectively, enlarged and shrunk the temporal window of illusion, suggesting that alpha oscillations might represent the temporal unit of visual processing that cyclically gates perception and the neurophysiological substrate promoting audio-visual interactions.
Slagter, Heleen A.; Davidson, Richard J.; Tomer, Rachel
Most healthy individuals display a subtle spatial attentional bias, exhibiting relative inattention for stimuli on one side of the visual field, a phenomenon known as pseudoneglect. Prior work in animals and patients has implicated dopamine in spatial attention asymmetries. The current study therefore examined - in healthy individuals - the relationship between the attentional bias and spontaneous eye-blink rate (EBR), a putative measure of central dopaminergic function. We found that those individuals, who blinked more often under resting conditions, displayed greater preference for the right side of the visual display in a subsequent attention task. This finding may support the idea that the observed attentional bias in healthy individuals reflects asymmetries in dopaminergic circuits, and corroborates previous findings implicating dopamine in spatial attention. PMID:20036680
Moses, Tim; Zhang, Wenmin
The purpose of this article was to extend the use of standard errors for equated score differences (SEEDs) to traditional equating functions. The SEEDs are described in terms of their original proposal for kernel equating functions and extended so that SEEDs for traditional linear and traditional equipercentile equating functions can be computed.…
Redolat, Rosa; Pérez-Martínez, Asunción; Carrasco, M Carmen; Mesa, Patricia
Individual differences in the behavioral responses to a novel environment have been proposed as a research tool to predict responsiveness to other behavioral tasks, response to certain events and individual vulnerability to nicotine addiction. In rats and mice, novelty seeking (defined as enhanced specific exploration of novel situations) is a complex behavior confirmed by a large body of neurochemical, endocrinological and behavioral data. We review the main standardized procedures employed to measure the novelty seeking trait in rodents and the ontogeny of this behavior throughout the life-span taking into account that novelty seeking can be permanently modified as a consequence of particular early experiences, maternal care, and environmental enrichment. Studies in animal models suggest that individual differences in the sensitivity to nicotine depend on different variables such as basal locomotor activity of the experimental subjects, their response to novel environments (open-field, hole-board) and level of impulsivity. It is concluded that these basic findings contribute to a better understanding of smoking behavior and to the establishment of improved pharmacological treatments if individual differences are borne in mind.
Miller, Michael B; Donovan, Christa-Lynn; Bennett, Craig M; Aminoff, Elissa M; Mayer, Richard E
Neuroimaging is being used increasingly to make inferences about an individual. Yet, those inferences are often confounded by the fact that topographical patterns of task-related brain activity can vary greatly from person to person. This study examined two factors that may contribute to the variability across individuals in a memory retrieval task: individual differences in cognitive style and individual differences in encoding strategy. Cognitive style was probed using a battery of assessments focused on the individual's tendency to visualize or verbalize written material. Encoding strategy was probed using a series of questions designed to assess typical strategies that an individual might utilize when trying to remember a list of words. Similarity in brain activity was assessed by cross-correlating individual t-statistic maps contrasting the BOLD response during retrieval to the BOLD response during fixation. Individual differences in cognitive style and encoding strategy accounted for a significant portion of the variance in similarity. This was true above and beyond individual differences in anatomy and memory performance. These results demonstrate the need for a multidimensional approach in the use of fMRI to make inferences about an individual.
Anjum, Amber Nasreen; Al-Othmany, Dheya Shujaa; Hussain, Ahmad
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…
Berthier, Neil E.; Boucher, Kelsea; Weisner, Nina
Children's performance on cognitive tasks is often described in categorical terms in that a child is described as either passing or failing a test, or knowing or not knowing some concept. We used binomial mixture models to determine whether individual children could be classified as passing or failing two search tasks, the DeLoache model room…
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…
Studied relationships between boredom at work, personal characteristics, and performance in a sample of truck drivers. Results suggest that boredom was associated negatively with higher mental and physical individual capacity and negatively associated with effectiveness. The relationship between boredom and work effectiveness was significantly…
Willows, Dale M.
Good, normal, and poor third grade readers were required to read easy, moderate, and difficult one-syllable nouns under three conditions: control condition with no pictures, identifying-picture condition, and unrelated-picture condition. Reading performance of poor readers was influenced by pictures under all conditions. Individual differences…
Flores, Raymond; Ari, Fatih; Inan, Fethi A.; Arslan-Ari, Ismahan
Combining adaptive hypermedia methods with strategies proposed by instructional theory and motivation models, an adaptable tutorial was designed and developed. The aim of this study was to assess whether the goals of an adaptable tutorial, which individualized instruction based on student motivation and prior knowledge, were being met (i.e.…
Argues that an evolutionary perspective can unite the study of species-typical development and individual variation. Provides examples from the domains of personality, social, and intellectual development. Maintains that understanding the ways in which genes and environments work together helps developmentalists identify children who need…
The notion of language as a complex adaptive system has been conceived within an agent-based framework, which highlights the significance of individual-level variation in the characteristics and contextual circumstances of the learner/speaker. Yet, in spite of this emphasis, currently we know relatively little about the interplay among language,…
frequently face the problem of information overload . The amount of information available for a decision is often much larger than a person can process to make...team performance and can lead to information overload if it is coupled with high information push activity. Similarly, heuristic decisions as a...today’s networks, individuals frequently face the problem of information overload : the amount of information available for a decision far ex- ceeds the
battery of personality traits referred to as the Navy Computer Adaptive Personality Scales (NCAPS) because it’s 19 traits cover the characteristics that...Navy-developed battery of personality traits referred to as the Navy Computer Adaptive Personality Scales (NCAPS) because it covers the characteristics...context, “individual differences” will refer to measures of constructs that differentiate (or scale ) people relative to one another. vii
Pumarola-Suñé, J; Solá-Vicens, L; Sentís-Vilalta, J; Canalda-Sahli, C; Brau-Aguadé, E
A comparative study of the absorbency properties of different endodontic paper points has been conducted. Twenty standardized absorbent paper points, size 30, from 13 bands (Dentaline, Zipperer, Kerr, Diadent, Roeko novo, Roeko color, Maillefer, P.D., Schein, Spectrapoint, Proclinic, Euronda, and Alpro) of 12 manufacturers were tested. Each dry paper point was weighted using an electronic laboratory balance. A length of 16 mm from the tip was then lowered in distilled water for 5 s, the paper point was weighted again, and the difference between both measurements was taken as the value of the fluid absorbed. Diadent, Kerr, and Dentalite showed significantly higher absorbencies (p < 0.05) than standardized paper points of the remaining brands. The study demonstrates a wide variation in the absorbency properties of this dental accessory.
... 40 Protection of Environment 22 2014-07-01 2013-07-01 true How may I switch from my individual RCRA permit to a standardized permit? 124.203 Section 124.203 Protection of Environment ENVIRONMENTAL... Permit Applying for A Standardized Permit § 124.203 How may I switch from my individual RCRA permit to...
... 40 Protection of Environment 23 2012-07-01 2012-07-01 false How may I switch from my individual RCRA permit to a standardized permit? 124.203 Section 124.203 Protection of Environment ENVIRONMENTAL... Permit Applying for A Standardized Permit § 124.203 How may I switch from my individual RCRA permit to...
... 40 Protection of Environment 23 2013-07-01 2013-07-01 false How may I switch from my individual RCRA permit to a standardized permit? 124.203 Section 124.203 Protection of Environment ENVIRONMENTAL... Permit Applying for A Standardized Permit § 124.203 How may I switch from my individual RCRA permit to...
... 40 Protection of Environment 22 2011-07-01 2011-07-01 false How may I switch from my individual RCRA permit to a standardized permit? 124.203 Section 124.203 Protection of Environment ENVIRONMENTAL... Permit Applying for A Standardized Permit § 124.203 How may I switch from my individual RCRA permit to...
... 40 Protection of Environment 21 2010-07-01 2010-07-01 false How may I switch from my individual RCRA permit to a standardized permit? 124.203 Section 124.203 Protection of Environment ENVIRONMENTAL... Permit Applying for A Standardized Permit § 124.203 How may I switch from my individual RCRA permit to...
Olsson, Andreas; Carmona, Susanna; Downey, Geraldine; Bolger, Niall; Ochsner, Kevin N.
People vary greatly in their dispositions to anxiously expect, readily perceive, and strongly react to social rejection (rejection sensitivity, RS) with implications for social functioning and health. Here, we examined how RS influences learning about social threat. Using a classical fear conditioning task, we established that high as compared to low (HRS vs. LRS) individuals displayed a resistance to extinction of the conditioned response to angry faces, but not to neutral faces or non-social stimuli. Our findings suggest that RS biases the flexible updating of acquired expectations for threat, which helps to explain how RS operates as a self-fulfilling prophecy. PMID:23914767
Ciochină, Laura; Faria, Luísa
This article presents the results of a series of preliminary comparisons, between the Portuguese and Romanian cultural contexts, on the individualism-collectivism (IND/COL) cultural dimension. The IND/COL was evaluated with the Individualism-Collectivism Questionnaire - ICQ -, constructed in New Zealand by Shulruf, Hattie and Dixon (2003, Anonymous Questionnaire of Self-Attitudes - AQSA), and adapted to the Portuguese and Romanian contexts by Ciochină and Faria (2007), using studies of confirmatory factor analysis. The ICQ composed by 26 items, 15 evaluating the IND scale--with three subscales (Uniqueness, Competition and Responsibility)--, and 11 evaluating the COL scale--with two subscales (Harmony and Advice)--, was administered to 395 subjects, 200 Portuguese and 195 Romanian, 10th and 12th graders. On the whole, in the Portuguese and Romanian samples, the multivariate and univariate statistical analyses evidenced the existence of two independent variables--gender and cultural context--, with significant effects, main and of interaction, on the scales and subscales of the ICQ. The results were discussed taking into consideration the specificities of the educational systems in the two cultural contexts, which are inevitably shaped by socio-cultural factors characteristic of the two countries considered in the present study--Portugal and Romania.
Lewkowicz, Daniel; Quesque, Francois; Coello, Yann; Delevoye-Turrell, Yvonne N.
As social animals, it is crucial to understand others’ intention. But is it possible to detect social intention in two actions that have the exact same motor goal? In the present study, we presented participants with video clips of an individual reaching for and grasping an object to either use it (personal trial) or to give his partner the opportunity to use it (social trial). In Experiment 1, the ability of naïve participants to classify correctly social trials through simple observation of short video clips was tested. In addition, detection levels were analyzed as a function of individual scores in psychological questionnaires of motor imagery, visual imagery, and social cognition. Results revealed that the between-participant heterogeneity in the ability to distinguish social from personal actions was predicted by the social skill abilities. A second experiment was then conducted to assess what predictive mechanism could contribute to the detection of social intention. Video clips were sliced and normalized to control for either the reaction times (RTs) or/and the movement times (MTs) of the grasping action. Tested in a second group of participants, results showed that the detection of social intention relies on the variation of both RT and MT that are implicitly perceived in the grasping action. The ability to use implicitly these motor deviants for action-outcome understanding would be the key to intuitive social interaction. PMID:26347673
Research on the relationship between cohabitation and mental health tends to ignore social psychological factors that help explain mental health differences between the married and the unmarried, including coping resources and perceived relationship quality. In this paper I draw on social psychological theory and research to clarify differences in…
Sprecher, Susan; Treger, Stanislav; Sakaluk, John K
In this article, we present results from a "cohort-longitudinal" analysis of sexual attitudes and behaviors based on a large sample of young adults (N = 7,777) obtained from a university setting over a 23-year period. We investigated gender, ethnicity, and cohort differences in sexual permissiveness, endorsement of the double standard, and sociosexuality. Compared to women, men had more permissive attitudes, particularly about sex in casual relationships, endorsed the double standard to a greater degree, and had a more unrestricted sociosexuality. Black men were generally more permissive than White, Hispanic, and Asian men, whereas ethnic differences were not found among women. Participants from the 1995-1999 cohort were slightly less permissive than those from the 1990-1994 and 2005-2012 cohorts. Although prior meta-analytic studies (e.g., Petersen & Hyde, 2010) found reduced gender differences in sexuality over time, our cohort analyses suggest that gender differences in sexual permissiveness have not changed over the past two decades among college students.
Risholm-Sundman, Maria; Larsen, Annelise; Vestin, Ewa; Weibull, Anders
The emission of formaldehyde is an important factor in the evaluation of the environmental and health effects of wood-based board materials. This article gives a comparison between commonly used European test methods: chamber method [EN 717-1, 2004. Wood-based panels—determination of formaldehyde release—Part 1: formaldehyde emission by the chamber method. European Standard, October 2004], gas analysis method [EN 717-2, 1994. Wood-based panels—determination of formaldehyde release—Part 2: formaldehyde release by the gas analysis method, European Standard, November 1994], flask method [EN 717-3, 1996. Wood-based panels—determination of formaldehyde release—Part 3: formaldehyde release by the flask method, European Standard, March 1996], perforator method [EN 120, 1993. Wood based panels—determination of formaldehyde content—extraction method called perforator method, European Standard, September 1993], Japanese test methods: desiccator methods [JIS A 1460, 2001. Building boards. Determination of formaldehyde emission—desiccator method, Japanese Industrial Standard, March 2001 and JAS MAFF 233, 2001] and small chamber method [JIS A 1901, 2003. Determination of the emission of volatile organic compounds and aldehydes for building products—small chamber method, Japanese Industrial Standard, January 2003], for solid wood, particleboard, plywood and medium density fiberboard. The variations between the results from different methods can partly be explained by differences in test conditions. Factors like edge sealing, conditioning of the sample before the test and test temperature have a large effect on the final emission result. The Japanese limit for F **** of 0.3 mg l -1 (in desiccator) for particleboards was found to be equivalent to 0.04 mg m -3 in the European chamber test and 2.8 mg per 100 g in the perforator test. The variations in inter-laboratory tests are much larger than in intra-laboratory tests; the coefficient of variation is 16% and 6
Janssen, Alisha L; Boster, Aaron; Patterson, Beth A; Abduljalil, Amir; Prakash, Ruchika Shaurya
Multiple sclerosis (MS) is a neurodegenerative, inflammatory disease of the central nervous system, resulting in physical and cognitive disturbances. The goal of the current study was to examine the association between network integrity and composite measures of cognition and disease severity in individuals with relapsing-remitting MS (RRMS), relative to healthy controls. All participants underwent a neuropsychological and neuroimaging session, where resting-state data was collected. Independent component analysis and dual regression were employed to examine network integrity in individuals with MS, relative to healthy controls. The MS sample exhibited less connectivity in the motor and visual networks, relative to healthy controls, after controlling for group differences in gray matter volume. However, no alterations were observed in the frontoparietal, executive control, or default-mode networks, despite previous evidence of altered neuronal patterns during tasks of exogenous processing. Whole-brain, voxel-wise regression analyses with disease severity and processing speed composites were also performed to elucidate the brain-behavior relationship with neuronal network integrity. Individuals with higher levels of disease severity demonstrated reduced intra-network connectivity of the motor network, and the executive control network, while higher disease burden was associated with greater inter-network connectivity between the medial visual network and areas involved in visuomotor learning. Our findings underscore the importance of examining resting-state oscillations in this population, both as a biomarker of disease progression and a potential target for therapeutic intervention.
line such as “XJK ___ XRK.” Participants were to write S on the line if the pairs were the same or D if they were different. In pattern comparison...and non-medicated samples of children with and without ADHD : A meta-analytic review. Journal of Child Psychology and Psychiatry, 37, 971-987...Salthouse, T. A., Hambrick, D. Z., Lukas, K. E., & Dell, T. C. (1996). Determinants of adult age differences on synthetic work performance. Journal of
Grimm, Volker; Berger, Uta; Bastiansen, Finn; Eliassen, Sigrunn; Ginot, Vincent; Giske, Jarl; Goss-Custard, John; Grand, Tamara; Heinz, Simone K.; Huse, Geir; Huth, Andreas; Jepsen, Jane U.; Jorgensen, Christian; Mooij, Wolf M.; Muller, Birgit; Pe'er, Guy; Piou, Cyril; Railsback, Steven F.; Robbins, Andrew M.; Robbins, Martha M.; Rossmanith, Eva; Ruger, Nadja; Strand, Espen; Souissi, Sami; Stillman, Richard A.; Vabo, Rune; Visser, Ute; DeAngelis, Donald L.
Simulation models that describe autonomous individual organisms (individual based models, IBM) or agents (agent-based models, ABM) have become a widely used tool, not only in ecology, but also in many other disciplines dealing with complex systems made up of autonomous entities. However, there is no standard protocol for describing such simulation models, which can make them difficult to understand and to duplicate. This paper presents a proposed standard protocol, ODD, for describing IBMs and ABMs, developed and tested by 28 modellers who cover a wide range of fields within ecology. This protocol consists of three blocks (Overview, Design concepts, and Details), which are subdivided into seven elements: Purpose, State variables and scales, Process overview and scheduling, Design concepts, Initialization, Input, and Submodels. We explain which aspects of a model should be described in each element, and we present an example to illustrate the protocol in use. In addition, 19 examples are available in an Online Appendix. We consider ODD as a first step for establishing a more detailed common format of the description of IBMs and ABMs. Once initiated, the protocol will hopefully evolve as it becomes used by a sufficiently large proportion of modellers.
Fernández-Reiriz, María José; Irisarri, Jade; Labarta, Uxio
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.
Fernández-Reiriz, María José; Irisarri, Jade; Labarta, Uxio
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. PMID:26849372
Metzler-Baddeley, Claudia; Baddeley, Roland J.; Jones, Derek K.; Aggleton, John P.; O’Sullivan, Michael J.
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. PMID:23555805
Chavez, Robert S; Heatherton, Todd F
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.
Lindskog, Marcus; Winman, Anders; Poom, Leo
Math anxiety (MA) involves negative affect and tension when solving mathematical problems, with potentially life-long consequences. MA has been hypothesized to be a consequence of negative learning experiences and cognitive predispositions. Recent research indicates genetic and neurophysiological links, suggesting that MA stems from a basic level deficiency in symbolic numerical processing. However, the contribution of evolutionary ancient purely nonverbal processes is not fully understood. Here we show that the roots of MA may go beyond symbolic numbers. We demonstrate that MA is correlated with precision of the Approximate Number System (ANS). Individuals high in MA have poorer ANS functioning than those low in MA. This correlation remains significant when controlling for other forms of anxiety and for cognitive variables. We show that MA mediates the documented correlation between ANS precision and math performance, both with ANS and with math performance as independent variable in the mediation model. In light of our results, we discuss the possibility that MA has deep roots, stemming from a non-verbal number processing deficiency. The findings provide new evidence advancing the theoretical understanding of the developmental etiology of MA.
Glenn, Andrea L.; Yang, Yaling; Raine, Adrian; Colletti, Patrick
Functional imaging studies of psychopathy have demonstrated reduced activity in the anterior cingulate, yet it is unclear whether this region is structurally impaired. In this study, we used structural MRI to examine whether volumetric differences exist in the anterior cingulate between psychopathic (n=24) and control (n=24) male participants. We found no group differences in the volume of the anterior cingulate or its dorsal and ventral subregions. Our findings call into question whether the anterior cingulate is impaired in psychopathy, or whether previous findings of reduced activity may result from reduced input from other deficient regions. PMID:20630717
McGuire, Sarah; Müller, Uwe; Elmenhorst, Eva-Maria; Basner, Mathias
Study Objectives: Environmental noise exposure disturbs sleep and impairs recuperation, and may contribute to the increased risk for (cardiovascular) disease. Noise policy and regulation are usually based on average responses despite potentially large inter-individual differences in the effects of traffic noise on sleep. In this analysis, we investigated what percentage of the total variance in noise-induced awakening reactions can be explained by stable inter-individual differences. Methods: We investigated 69 healthy subjects polysomnographically (mean ± standard deviation 40 ± 13 years, range 18–68 years, 32 male) in this randomized, balanced, double-blind, repeated measures laboratory study. This study included one adaptation night, 9 nights with exposure to 40, 80, or 120 road, rail, and/or air traffic noise events (including one noise-free control night), and one recovery night. Results: Mixed-effects models of variance controlling for reaction probability in noise-free control nights, age, sex, number of noise events, and study night showed that 40.5% of the total variance in awakening probability and 52.0% of the total variance in EEG arousal probability were explained by inter-individual differences. If the data set was restricted to nights (4 exposure nights with 80 noise events per night), 46.7% of the total variance in awakening probability and 57.9% of the total variance in EEG arousal probability were explained by inter-individual differences. The results thus demonstrate that, even in this relatively homogeneous, healthy, adult study population, a considerable amount of the variance observed in noise-induced sleep disturbance can be explained by inter-individual differences that cannot be explained by age, gender, or specific study design aspects. Conclusions: It will be important to identify those at higher risk for noise induced sleep disturbance. Furthermore, the custom to base noise policy and legislation on average responses should be re
Leung, S. Alvin; Harmon, Lenore W.
Examined zone of acceptable alternatives construct from Gottfredson's theory of career aspiration. College students' (N=246) responses to Occupations List were coded with measurements of sex type and prestige, and indicators of zone of acceptable alternatives for subjects' were computed. Found changes over time and differences related to gender…
Feldman, Marc; Kumar, V. K.; Angelini, Frank; Pekala, Ronald J.; Porter, Jack
Using H. J. Eysenck's (1957,1967) theory of temperament, this study examined the relationship between drug preference, drug use, and personality among incarcerated inmates. Analysis indicated a general preference for marijuana and alcohol over 8 other commonly used drugs across different personality types. Theoretical and clinical implications are…
Abé, Christoph; Johansson, Emilia; Allzén, Elin; Savic, Ivanka
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.
Furnham, Adrian; Batey, Mark; Booth, Tom W.; Patel, Vikita; Lozinskaya, Dariya
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…
From an instructional perspective, it is conceivable that employing an appropriate hypertext architecture should have the advantage of facilitating learning by representing logically the interrelationships between the different pieces of information contained within the hypertext. Furthermore, there would however appear to be a sound theoretical…
Unsworth, Nash; Brewer, Gene A.
The relation between intrusions in several different recall tasks was examined in the current study. Intrusions from these tasks were moderately correlated and formed a unitary intrusion factor. This factor was related to other cognitive ability measures including working memory capacity, judgments of recency, and general source-monitoring…
Abé, Christoph; Johansson, Emilia; Allzén, Elin; Savic, Ivanka
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. PMID:25479554
Card, Josefina Jayme; And Others
Women had higher high school grades and academic ability test scores in Grade 9. By 11 years after high school, men had more education and were earning more money. Sex differences in realization of achievement potential were found across all socioeconomic levels, and found to be partially due to role conflict. (Author/JAC)
Gasquoine, Philip Gerard; Gonzalez, Cassandra Dayanira
Conventional neuropsychological norms developed for monolinguals likely overestimate normal performance in bilinguals on language but not visual-perceptual format tests. This was studied by comparing neuropsychological false-positive rates using the 50th percentile of conventional norms and individual comparison standards (Picture Vocabulary or Matrix Reasoning scores) as estimates of preexisting neuropsychological skill level against the number expected from the normal distribution for a consecutive sample of 56 neurologically intact, bilingual, Hispanic Americans. Participants were tested in separate sessions in Spanish and English in the counterbalanced order on La Bateria Neuropsicologica and the original English language tests on which this battery was based. For language format measures, repeated-measures multivariate analysis of variance showed that individual estimates of preexisting skill level in English generated the mean number of false positives most approximate to that expected from the normal distribution, whereas the 50th percentile of conventional English language norms did the same for visual-perceptual format measures. When using conventional Spanish or English monolingual norms for language format neuropsychological measures with bilingual Hispanic Americans, individual estimates of preexisting skill level are recommended over the 50th percentile.
Wickens, Christopher D.; Raby, Mireille
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.
Vingerhoets, Guy; Sarrechia, Iemke
Confusion or frustration connected with daily demands involving left-right discrimination is a common observation even in neurologically intact adults. We aimed to test the hypothesis that the degree of left-right confusion is associated with bodily asymmetry. Sixty-two female volunteers performed a left-right decision task that required fast responses to visually presented directional words (left, right, up, down) or pictograms (<--, -->, upward arrow, downward arrow). Participants also performed several tests that measured asymmetry of handedness, grip strength, and tactile sensitivity, and completed self-reports on left-right confusion and perceived bodily asymmetry. Results showed significant correlations between left-right confusion and the degree of handedness and asymmetry in tactile sensitivity. These results suggest that individuals who reveal a stronger internal bias between both sides of the body show less left-right confusion than people with less salient bodily asymmetry.
Gauss, Boris; Urbas, Leon
Reports the design and evaluation of a prototype for learning modules compliant to the SCORM (Sharable Content Object Reference Model) standard for use with hypermedia systems in Web-based instruction. Discusses a study of undergraduates that considered relations between individual differences in learner characteristics, including intrinsic…
Crossley, Scott A.; Allen, Laura K.; Snow, Erica L.; McNamara, Danielle S.
This study investigates a novel approach to automatically assessing essay quality that combines natural language processing approaches that assess text features with approaches that assess individual differences in writers such as demographic information, standardized test scores, and survey results. The results demonstrate that combining text…
Petersen, Michael Bang; Aarøe, Lene
We apply error management theory to the analysis of individual differences in the negativity bias and political ideology. Using principles from evolutionary psychology, we propose a coherent theoretical framework for understanding (1) why individuals differ in their political ideology and (2) the conditions under which these individual differences influence and fail to influence the political choices people make.
Parrilla, Inma; del Olmo, David; Sijses, Laurien; Martinez-Alborcia, María J; Cuello, Cristina; Vazquez, Juan M; Martinez, Emilio A; Roca, Jordi
The present study aimed to evaluate the ability of spermatozoa from individual boar ejaculates to withstand different semen-processing techniques. Eighteen sperm-rich ejaculate samples from six boars (three per boar) were diluted in Beltsville Thawing Solution and split into three aliquots. The aliquots were (1) further diluted to 3×10(7) sperm/mL and stored as a liquid at 17°C for 72 h, (2) frozen-thawed (FT) at 1×10(9) sperm/mL using standard 0.5-mL straw protocols, or (3) sex-sorted with subsequent liquid storage (at 17°C for 6 h) or FT (2×10(7) sperm/mL using a standard 0.25-mL straw protocol). The sperm quality was evaluated based on total sperm motility (the CASA system), viability (plasma membrane integrity assessed using flow cytometry and the LIVE/DEAD Sperm Viability Kit), lipid peroxidation (assessed via indirect measurement of the generation of malondialdehyde (MDA) using the BIOXYTECH MDA-586 Assay Kit) and DNA fragmentation (sperm chromatin dispersion assessed using the Sperm-Sus-Halomax(®) test). Data were normalized to the values assessed for the fresh (for liquid-stored and FT samples) or the sorted semen samples (for liquid stored and the FT sorted spermatozoa). All of the four sperm-processing techniques affected sperm quality (P<0.01), regardless of the semen donor, with reduced percentages of motile and viable sperm and increased MDA generation and percentages of sperm with fragmented DNA. Significant (P<0.05) inter-boar (effect of boars within each semen-processing technique) and intra-boar (effect of semen-processing techniques within each boar) differences were evident for all of the sperm quality parameters assessed, indicating differences in the ability of spermatozoa from individual boars to withstand the semen-processing techniques. These results are the first evidence that ejaculate spermatozoa from individual boars can respond in a boar-dependent manner to different semen-processing techniques.
Bonnelle, Valerie; Manohar, Sanjay; Behrens, Tim; Husain, Masud
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.
Cirilli, Laetitia; de Timary, Philippe; Lefèvre, Phillipe; Missal, Marcus
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.
Bonnelle, Valerie; Manohar, Sanjay; Behrens, Tim; Husain, Masud
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
Labrenz, Franziska; Themann, Maria; Wascher, Edmund; Beste, Christian; Pfleiderer, Bettina
Attentional mechanisms are a crucial prerequisite to organize behavior. Most situations may be characterized by a 'competition' between salient, but irrelevant stimuli and less salient, relevant stimuli. In such situations top-down and bottom-up mechanisms interact with each other. In the present fMRI study, we examined how interindividual differences in resolving situations of perceptual conflict are reflected in brain networks mediating attentional selection. Doing so, we employed a change detection task in which subjects had to detect luminance changes in the presence and absence of competing distractors. The results show that good performers presented increased activation in the orbitofrontal cortex (BA 11), anterior cingulate (BA 25), inferior parietal lobule (BA 40) and visual areas V2 and V3 but decreased activation in BA 39. This suggests that areas mediating top-down attentional control are stronger activated in this group. Increased activity in visual areas reflects distinct neuronal enhancement relating to selective attentional mechanisms in order to solve the perceptual conflict. Opposed to good performers, brain areas activated by poor performers comprised the left inferior parietal lobule (BA 39) and fronto-parietal and visual regions were continuously deactivated, suggesting that poor performers perceive stronger conflict than good performers. Moreover, the suppression of neural activation in visual areas might indicate a strategy of poor performers to inhibit the processing of the irrelevant non-target feature. These results indicate that high sensitivity in perceptual areas and increased attentional control led to less conflict in stimulus processing and consequently to higher performance in competitive attentional selection.
Gifford, Matthew E; Clay, Timothy A; Careau, Vincent
Repeatability is an important concept in evolutionary analyses because it provides information regarding the benefit of repeated measurements and, in most cases, a putative upper limit to heritability estimates. Repeatability (R) of different aspects of energy metabolism and behavior has been demonstrated in a variety of organisms over short and long time intervals. Recent research suggests that consistent individual differences in behavior and energy metabolism might covary. Here we present new data on the repeatability of body mass, standard metabolic rate (SMR), voluntary exploratory behavior, and feeding rate in a semiaquatic salamander and ask whether individual variation in behavioral traits is correlated with individual variation in metabolism on a whole-animal basis and after conditioning on body mass. All measured traits were repeatable, but the repeatability estimates ranged from very high for body mass (R = 0.98), to intermediate for SMR (R = 0.39) and food intake (R = 0.58), to low for exploratory behavior (R = 0.25). Moreover, repeatability estimates for all traits except body mass declined over time (i.e., from 3 to 9 wk), although this pattern could be a consequence of the relatively low sample size used in this study. Despite significant repeatability in all traits, we find little evidence that behaviors are correlated with SMR at the phenotypic and among-individual levels when conditioned on body mass. Specifically, the phenotypic correlations between SMR and exploratory behavior were negative in all trials but significantly so in one trial only. Salamanders in this study showed individual variation in how their exploratory behavior changed across trials (but not body mass, SMR, and feed intake), which might have contributed to observed changing correlations across trials.
O'Hearn, Kirsten; Landau, Barbara
Williams syndrome (WS) is a developmental disorder associated with relatively spared verbal skills and severe visuospatial deficits. It has also been reported that individuals with WS are impaired at mathematics. We examined mathematical skills in persons with WS using the second edition of the Test of Early Mathematical Ability (TEMA-2), which measures a wide range of skills. We administered the TEMA-2 to 14 individuals with WS and 14 children matched individually for mental-age on the matrices subtest of the Kaufman Brief Intelligence Test. There were no differences between groups on the overall scores on the TEMA-2. However, an item-by-item analysis revealed group differences. Participants with WS performed more poorly than controls when reporting which of two numbers was closest to a target number, a task thought to utilize a mental number line subserved by the parietal lobe, consistent with previous evidence showing parietal abnormalities in people with WS. In contrast, people with WS performed better than the control group at reading numbers, suggesting that verbal math skills may be comparatively strong in WS. These findings add to evidence that components of mathematical knowledge may be differentially damaged in developmental disorders.
Si, Jiwei; Li, Hongxia; Sun, Yan; Xu, Yanli; Sun, Yu
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.
Cannabis is a complex plant, with major compounds such as delta-9-tetrahydrocannabinol and cannabidiol, which have opposing effects. The discovery of its compounds has led to the further discovery of an important neurotransmitter system called the endocannabinoid system. This system is widely distributed in the brain and in the body, and is considered to be responsible for numerous significant functions. There has been a recent and consistent worldwide increase in cannabis potency, with increasing associated health concerns. A number of epidemiological research projects have shown links between dose-related cannabis use and an increased risk of development of an enduring psychotic illness. However, it is also known that not everyone who uses cannabis is affected adversely in the same way. What makes someone more susceptible to its negative effects is not yet known, however there are some emerging vulnerability factors, ranging from certain genes to personality characteristics. In this article we first provide an overview of the biochemical basis of cannabis research by examining the different effects of the two main compounds of the plant and the endocannabinoid system, and then go on to review available information on the possible factors explaining variation of its effects upon different individuals.
Damos, D. L.
Human factors practitioners often are concerned with mental workload in multiple-task situations. Investigations of these situations have demonstrated repeatedly that individuals differ in their subjective estimates of workload. These differences may be attributed in part to individual differences in definitions of workload. However, after allowing for differences in the definition of workload, there are still unexplained individual differences in workload ratings. The relation between individual differences in multiple-task performance, subjective estimates of workload, information processing abilities, and the Type A personality trait were examined.
Eftimovska–Otovic, Natasa; Stojceva-Taneva, Olivera; Grozdanovski, Risto; Stojcev, Saso
BACKGROUND: The degree to which the dialysate prescription and, in particular, the dialysate sodium concentration influences blood pressure and interdialytic weight gain (IDWG) via changes in sodium flux, plasma volume or the other parameters is not well understood. The aim of the study was to investigate whether dialysis patients will have some beneficial effects of dialysate sodium set up according to serum sodium or sodium modeling. MATERIAL AND METHODS: Ninety-two nondiabetic subjects (52 men and 40 women) performed 12 consecutive hemodialysis (HD) sessions (4 weeks) with dialysate sodium concentration set up on 138 mmol/L (standard sodium – first phase), followed by 24 sessions (second phase) wherein dialysate sodium was set up according to individualized sodium. Variables of interest were: systolic, diastolic and mean blood pressure, pulse, IDWG, thirst score – (Xerostomia Inventory (XI) and Dialysis Thirst Inventory (DTI)) and side effects (occurrence of hypotension and muscle cramps). After the first phase, the subjects were divided into 3 groups: normotensive (N=76), hypertensive (N= 11) and hypotensive (N=5) based on the average pre-HD systolic BP during the whole period of the first phase. RESULTS: Sodium individualization resulted in significantly lower blood pressure (133.61 ± 11.88 versus 153.60 ± 14.26 mmHg; p=0.000) and IDWG (2.21 ± 0.93 versus 1.87 ± 0.92 kg; p=0.018) in hypertensive patients, whereas normotensive patients showed only significant decrease in IDWG (2.21 ± 0.72 versus 2.06 ± 0.65, p=0,004). Sodium profiling in hypotensive patients significantly increased IDWG (2.45 vs. 2.74, p= 0,006), and had no impact on blood pressure. Thirst score was significantly lower in normotensive patients with individualized-sodium HD and showed no change in the other two groups. During the second phase, hypotension occurred in only 1 case and muscle cramps in 10 normotensive patients. CONCLUSION: Individualized sodium resulted in clinical
Bijvoet-van den Berg, Simone; Hoicka, Elena
Divergent thinking shows the ability to search for new ideas, which is an important factor contributing to innovation and problem solving. Current divergent thinking tests allow researchers to study children's divergent thinking from the age of 3 years on. This article presents the first measure of divergent thinking that can be used with children as young as 2 years. The Unusual Box test is a nonverbal and nonimitative test in which children play individually with a novel toy and novel objects. Divergent thinking is scored as the number of different actions performed. Study 1 shows that the Unusual Box test is a valid measure of divergent thinking as it correlates with standard measures of divergent thinking in 3- and 4-year-olds. Study 2 indicates that the test can be used with 2-year-olds, as it shows high test-retest reliability, demonstrating that 2-year-olds can think divergently. Across both studies, individual differences and age-related changes were found, indicating that some children are better at divergent thinking than others and that children's divergent thinking increases with age. This test will allow researchers to gain insight into the early emergence of divergent thinking.
Atkinson, R P; Crawford, H J
To investigate the moderating role of individual differences in hypnotic susceptibility and visuospatial skills on afterimage persistence, we presented a codable (cross) flash of light to 40 men and 46 women who had been dark adapted for 20 min. In an unrelated classroom setting, subjects had previously been given two standardized scales of hypnotic susceptibility (Harvard Group Scale of Hypnotic Susceptibility, Shor & Orne, 1962; Group Stanford Hypnotic Susceptibility Scale, Form C, Crawford & Allen, 1982) and the Mental Rotations Test (Vandenberg & Kuse, 1978). The first afterimage interval and the afterimage duration correlated significantly with hypnotic responsiveness, supporting Wallace (1979), but did not show the anticipated relationships with mental rotation visuospatial skills. Individuals in the high hypnotizable group had (a) significantly longer afterimage intervals between its first appearance and first disappearance than did those in medium or low groups, as well as (b) significantly longer afterimages between the first appearance and the final disappearance than did those in low groups, but those in medium groups did not differ significantly from the other groups. Discriminant analysis using the afterimage persistence measures classified correctly 65.2% of high hypnotizables, 37.5% of medium hypnotizables, and 54.8% of low hypnotizables. Hypothesized cognitive skills that assist in the maintenance of afterimages and underlie hypnotic susceptibility include abilities to maintain focused attention and resist distractions over time and to maintain vivid visual images.
Qutubuddin, Abu A; Cifu, David X; Armistead-Jehle, Patrick; Carne, William; McGuirk, Theresa E; Baron, Mark S
Postural instability is a common impairment in idiopathic Parkinson's disease (PD). People with PD are prone to balance and walking difficulties. This study analyzed the feasibility of a prospective investigation of Computerized Dynamic Posturography (CDP) and standard Physical Therapy (PT) treatments in individuals with mild-moderate PD. Treatment took place at two sites: 1) CDP therapy at the Southeast Parkinson's Disease Research Education and Clinical Center (PADRECC) within a Veterans Affairs Medical Center and 2) standard physical therapy at a community outpatient rehabilitation center. Final analysis compared 15 patients randomly assigned for therapy to either the CDP or PT treatments. Therapy time was eight weeks (four weeks of CPD or PT followed by home therapy for four weeks). The CDP therapy included gradually intensified closed chain and mobility training. Standard PT consisted of upright, mat, and theraball exercises and gait training. The home exercise phase was identical for both groups. The pilot data demonstrated treatment was tolerated by 68 percent of the sample despite the occurrence of a progressive neurological condition and medical comorbidities. While results failed to reveal any differences between treatment groups, both groups demonstrated improvement on selected outcome measures. An expanded prospective study with methodological improvements appears warranted.
Dowd, Emma Wu; Kiyonaga, Anastasia; Egner, Tobias; Mitroff, Stephen R
The contents of working memory (WM) have been repeatedly found to guide the allocation of visual attention; in a dual-task paradigm that combines WM and visual search, actively holding an item in WM biases visual attention towards memory-matching items during search (e.g., Soto et al., Journal of Experimental Psychology: Human Perception and Performance, 31(2), 248-261, 2005). A key debate is whether such memory-based attentional guidance is automatic or under strategic control. Generally, two distinct task paradigms have been employed to assess memory-based guidance, one demonstrating that attention is involuntarily captured by memory-matching stimuli even at a cost to search performance (Soto et al., 2005), and one demonstrating that participants can strategically avoid memory-matching distractors to facilitate search performance (Woodman & Luck, Journal of Experimental Psychology: Human Perception and Performance, 33(2), 363-377, 2007). The current study utilized an individual-differences approach to examine why the different paradigms--which presumably tap into the same attentional construct--might support contrasting interpretations. Participants completed a battery of cognitive tasks, including two types of attentional guidance paradigms (see Soto et al., 2005; Woodman & Luck, 2007), a visual WM task, and an operation span task, as well as attention-related self-report assessments. Performance on the two attentional guidance paradigms did not correlate. Subsequent exploratory regression analyses revealed that memory-based guidance in each task was differentially predicted by visual WM capacity for one paradigm, and by attention-related assessment scores for the other paradigm. The current results suggest that these two paradigms--which have previously produced contrasting patterns of performance--may probe distinct aspects of attentional guidance.
Arminio, Jan; Gochenauer, Patty
Using members of professional associations who are a part of the Council for the Advancement of Standards in Higher Education (CAS) consortia as a sample, this study investigated who uses CAS Standards, how and why they are used, and whether CAS Standards are associated with enhanced student learning. Using a quantitative analysis, this study…
Compact difference schemes have been used extensively for solving the incompressible Navier-Stokes equations. However, the earlier formulations of the schemes are of central type (called central compact schemes, CCS), which are dispersive and susceptible to numerical instability. To enhance stability of CCS, the optimal upwind compact schemes (OUCS) are developed recently by adding high order dissipative terms to CCS. In this paper, it is found that OUCS are essentially not of the upwind type because they do not use upwind-biased but central type of stencils. Furthermore, OUCS are not the most optimal since orders of accuracy of OUCS are at least one order lower than the maximum achievable orders. New upwind compact schemes (called standard upwind compact schemes, SUCS) are developed in this paper. In contrast to OUCS, SUCS are constructed based completely on upwind-biased stencils and hence can gain adequate numerical dissipation with no need for introducing optimization calculations. Furthermore, SUCS can achieve the maximum achievable orders of accuracy and hence be more compact than OUCS. More importantly, SUCS have prominent advantages on combining the stable and high resolution properties which are demonstrated from the global spectral analyses and typical numerical experiments.
Less than 5% of colorectal adenomas will become malignant, but we do not have sufficient knowledge about their natural course to target removal of these 5% only. Thus, 95% of polypectomies are a waste of time exposing patients to a small risk of complications. Recently, a new type of polyps, sessile serrated polyps, has attracted attention. Previously considered innocuous, they are now found to have molecular similarities to cancer and some guidelines recommend to have them removed. These lesions are often flat, covered by mucous, not easily seen and situated in the proximal colon where the bowel wall is thinner. Thus, polypectomy carries a higher risk of perforation than predominantly left-sided, stalked adenomas - and we do not know what is gained in terms of cancer prevention. Screening is a neat balance between harms and benefit for presumptively healthy participants not interested in risk exposure to obtain confirmation of being healthy. The situation is quite different for patient worried about symptom. Thus, the standards set for evidence-based practice may be higher for screening than for routine clinics - a mechanism which may benefit patients in the long run.
Lopez-Duran, Nestor L.; Hajal, Nastassia J.; Olson, Sheryl L.; Felt, Barbara T.; Vazquez, Delia M.
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…
Akpan, Godwin A.; Essien, Emmanuel O.; Okure, Okure S.
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…
Senthong, Vichai; Chindaprasirt, Jarin; Sawanyawisuth, Kittisak; Aekphachaisawat, Noppadol; Chaowattanapanit, Suteeraporn; Limpawattana, Panita; Choonhakarn, Charoen; Sookprasert, Aumkhae
Background The Angoff method is one of the preferred methods for setting a passing level in an exam. Normally, group meetings are required, which may be a problem for busy medical educators. Here, we compared a modified Angoff individual method to the conventional group method. Methods Six clinical instructors were divided into two groups matched by teaching experience: modified Angoff individual method (three persons) and conventional group method (three persons). The passing scores were set by using the Angoff theory. The groups set the scores individually and then met to determine the passing score. In the modified Angoff individual method, passing scores were judged by each instructor and the final passing score was adjusted by the concordance method and reliability index. Results There were 94 fourth-year medical students who took the test. The mean (standard deviation) test score was 65.35 (8.38), with a median of 64 (range 46–82). The three individual instructors took 45, 60, and 60 minutes to finish the task, while the group spent 90 minutes in discussion. The final passing score in the modified Angoff individual method was 52.18 (56.75 minus 4.57) or 52 versus 51 from the standard group method. There was not much difference in numbers of failed students by either method (four versus three). Conclusion The modified Angoff individual method may be a feasible way to set a standard passing score with less time consumed and more independent rather than group work by instructors. PMID:24101890
Pisanski, Katarzyna; Nowak, Judyta; Sorokowski, Piotr
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.
Misyak, Jennifer B; Christiansen, Morten H; Tomblin, J Bruce
Considerable individual differences in language ability exist among normally developing children and adults. Whereas past research have attributed such differences to variations in verbal working memory or experience with language, we test the hypothesis that individual differences in statistical learning may be associated with differential language performance. We employ a novel paradigm for studying statistical learning on-line, combining a serial-reaction time task with artificial grammar learning. This task offers insights into both the timecourse of and individual differences in statistical learning. Experiment 1 charts the micro-level trajectory for statistical learning of nonadjacent dependencies and provides an on-line index of individual differences therein. In Experiment 2, these differences are then shown to predict variations in participants' on-line processing of long-distance dependencies involving center-embedded relative clauses. The findings suggest that individual differences in the ability to learn from experience through statistical learning may contribute to variations in linguistic performance.
Tanner, Gregory J.; Blundell, Malcolm J.; Colgrave, Michelle L.; Howitt, Crispin A.
Background Coeliacs require a life-long gluten-free diet supported by accurate measurement of gluten (hordein) in gluten-free food. The gluten-free food industry, with a value in excess of $6 billion in 2011, currently depends on two ELISA protocols calibrated against standards that may not be representative of the sample being assayed. Aim The factors affecting the accuracy of ELISA analysis of hordeins in beer were examined. Results A simple alcohol-dithiothreitol extraction protocol successfully extracts the majority of hordeins from barley flour and malt. Primary hordein standards were purified by FPLC. ELISA detected different classes of purified hordeins with vastly different sensitivity. The dissociation constant (Kd) for a given ELISA reaction with different hordeins varied by three orders of magnitude. The Kd of the same hordein determined by ELISA using different antibodies varied by up to two orders of magnitude. The choice of either ELISA kit or hordein standard may bias the results and confound interpretation. Conclusions Accurate determination of hordein requires that the hordein standard used to calibrate the ELISA reaction be identical in composition to the hordeins present in the test substance. In practice it is not feasible to isolate a representative hordein standard from each test food. We suggest that mass spectrometry is more reliable than ELISA, as ELISA enumerates only the concentration of particular amino-acid epitopes which may vary between different hordeins and may not be related to the absolute hordein concentration. MS quantification is undertaken using peptides that are specific and unique enabling the quantification of individual hordein isoforms. PMID:23509607
Send, Alexander F J; Al-Ayyash, Adel; Schecher, Sabrina; Rudofsky, Gottfried; Klein, Ulrike; Schaier, Matthias; Pruszydlo, Markus G; Witticke, Diana; Lohmann, Kristina; Kaltschmidt, Jens; Haefeli, Walter E; Seidling, Hanna M
Aims We aimed to develop a generic knowledge base with drug administration recommendations which allows the generation of a dynamic and comprehensive medication plan and to evaluate its comprehensibility and potential benefit in a qualitative pilot study with patients and physicians. Methods Based on a literature search and previously published medication plans, a prototype was developed and iteratively refined through qualitative evaluation (interviews with patients and focus group discussions with physicians). To develop the recommendations for safe administration of specific drugs we screened the summary of product characteristics (SmPC) of different exemplary brands, allocated the generated advice to groups with brands potentially requiring the same advice, and reviewed these allocations regarding applicability and appropriateness of the recommendations. Results For the recommendations, 411 SmPCs of 140 different active ingredients including all available galenic formulations, routes of administrations except infusions, and administration devices were screened. Finally, 515 distinct administration recommendations were included in the database. In 926 different generic groups, 29 879 allocations of brands to general advice, food advice, indications, step-by-step instructions, or combinations thereof were made. Thereby, 27 216 of the preselected allocations (91.1%) were confirmed as appropriate. In total, one third of the German drug market was labelled with information. Conclusions Generic grouping of brands according to their active ingredient and other drug characteristics and allocation of standardized administration recommendations is feasible for a large drug market and can be integrated in a medication plan. PMID:24007451
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
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.
Mjølstad, Bente Prytz; Kirkengen, Anna Luise; Getz, Linn; Hetlevik, Irene
Background Repeated encounters over time enable general practitioners (GPs) to accumulate biomedical and biographical knowledge about their patients. A growing body of evidence documenting the medical relevance of lifetime experiences indicates that health personnel ought to appraise this type of knowledge and consider how to incorporate it into their treatment of patients. In order to explore the interdisciplinary communication of such knowledge within Norwegian health care, we conducted a research project at the interface between general practice and a nursing home. Methods In the present study, nine Norwegian GPs were each interviewed about one of their patients who had recently been admitted to a nursing home for short-term rehabilitation. A successive interview conducted with each of these patients aimed at both validating the GP's information and exploring the patient's life story. The GP's treatment opinions and the patient's biographical information and treatment preferences were condensed into a biographical record presented to the nursing home staff. The transcripts of the interviews and the institutional treatment measures were compared and analysed, applying a phenomenological–hermeneutical framework. In the present article, we compare and discuss: (1) the GPs’ specific recommendations for their patients; (2) the patients’ own wishes and perceived needs; and (3) if and how this information was integrated into the institution's interventions and priorities. Results Each GP made rehabilitation recommendations, which included statements regarding both the patient's personality and life circumstances. The nursing home staff individualized their selection of therapeutic interventions based on defined standardized treatment approaches, without personalizing them. Conclusion We found that the institutional voice of medicine consistently tends to override the voice of the patient's lifeworld. Thus, despite the institution's best intentions, their efforts
Hughes, Claire; Jaffee, Sara R.; Happ, Francesca; Taylor, Alan; Caspi, Avshalom; Moffitt, Terrie E.
In this study of the origins of individual differences in theory of mind (ToM), the Environmental Risk (E-Risk) Longitudinal Twin Study sample of 1,116 sixty-month-old twin pairs completed a comprehensive battery of ToM tasks. Individual differences in ToM were striking and strongly associated with verbal ability. Behavioral genetic models of the…
Wolfe, Christopher R.; Fisher, Christopher R.
Little is known about individual differences in integrating numeric base-rates and qualitative text in making probability judgments. Fuzzy-Trace Theory predicts a preference for fuzzy processing. We conducted six studies to develop the FPPI, a reliable and valid instrument assessing individual differences in this fuzzy processing preference. It…
Olkoniemi, Henri; Ranta, Henri; Kaakinen, Johanna K.
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…
L., Grenblo, P., & Dean, J. B. (2002). Judgmental self-doubt: beliefs about one’s judgmental prowess. Personality and Individual Differences , 33 741...1998). Personal need for structure, the Einstellung task, and the effects of stress. Personality and Individual Differences , 24, 305-310. 29. Somers, M
Shinozaki, Natsuko; Ye, Bin; Yamada, Takuji; Yamamoto, Masayuki; Nagasaki, Masao; Tsuboi, Akito
Given the advent of massively parallel DNA sequencing, human microbiome is analyzed comprehensively by metagenomic approaches. However, the inter- and intra-individual variability and stability of the human microbiome remain poorly characterized, particularly at the intra-day level. This issue is of crucial importance for studies examining the effects of microbiome on human health. Here, we focused on bacteriome of oral plaques, for which repeated, time-controlled sampling is feasible. Eighty-one supragingival plaque subjects were collected from healthy individuals, examining multiple sites within the mouth at three time points (forenoon, evening, and night) over the course of 3 days. Bacterial composition was estimated by 16S rRNA sequencing and species-level profiling, resulting in identification of a total of 162 known bacterial species. We found that species compositions and their relative abundances were similar within individuals, and not between sampling time or tooth type. This suggests that species-level oral bacterial composition differs significantly between individuals, although the number of subjects is limited and the intra-individual variation also occurs. The majority of detected bacterial species (98.2%; 159/162), however, did not fluctuate over the course of the day, implying a largely stable oral microbiome on an intra-day time scale. In fact, the stability of this data set enabled us to estimate potential interactions between rare bacteria, with 40 co-occurrences supported by the existing literature. In summary, the present study provides a valuable basis for studies of the human microbiome, with significant implications in terms of biological and clinical outcomes. PMID:26121551
Farley, Frank H.; And Others
Two studies were reported which attempted to estimate the stability and construct validity of human salivary response as a measure of individual differences (IDs) in physiological arousal. Twenty-second base line estimates and 20-second response levels to four drops of lemon juice were measured, with the former value being removed from the latter…
von Rueden, Chris; Gavrilets, Sergey; Glowacki, Luke
Models of collective action infrequently account for differences across individuals beyond a limited set of strategies, ignoring variation in endowment (e.g. physical condition, wealth, knowledge, personality, support), individual costs of effort, or expected gains from cooperation. However, behavioural research indicates these inter-individual differences can have significant effects on the dynamics of collective action. The papers contributed to this theme issue evaluate how individual differences affect the propensity to cooperate, and how they can catalyse others' likelihood of cooperation (e.g. via leadership). Many of the papers emphasize the relationship between individual decisions and socio-ecological context, particularly the effect of group size. All together, the papers in this theme issue provide a more complete picture of collective action, by embracing the reality of inter-individual variation and its multiple roles in the success or failure of collective action.
von Rueden, Chris; Gavrilets, Sergey; Glowacki, Luke
Models of collective action infrequently account for differences across individuals beyond a limited set of strategies, ignoring variation in endowment (e.g. physical condition, wealth, knowledge, personality, support), individual costs of effort, or expected gains from cooperation. However, behavioural research indicates these inter-individual differences can have significant effects on the dynamics of collective action. The papers contributed to this theme issue evaluate how individual differences affect the propensity to cooperate, and how they can catalyse others’ likelihood of cooperation (e.g. via leadership). Many of the papers emphasize the relationship between individual decisions and socio-ecological context, particularly the effect of group size. All together, the papers in this theme issue provide a more complete picture of collective action, by embracing the reality of inter-individual variation and its multiple roles in the success or failure of collective action. PMID:26503677
Stein, Laura R.; Bell, Alison M.
Consistent individual differences in parenting are widespread; however, we know little about why there is variation in parenting behavior among individuals within species. One possible explanation for consistent individual differences in parenting is that individuals invest in different aspects of parental care, such as provisioning or defense. In this field study we measured consistent individual differences in parenting behavior and evaluated correlations between parenting and other behaviors in threespine stickleback (Gasterosteus aculeatus). We repeatedly measured male parenting behavior and male behavior in the presence of three different types of live intruders: a female, a conspecific male, and a predator, meant to provoke courtship, aggressive and antipredator behavior, respectively. While males plastically adjusted their reactions to different types of intruders, we found consistent individual differences in behavior (behavioral types) both within and across contexts, even after accounting for variation in body size and nest characteristics. Males that performed more parenting behavior responded faster to all types of intruders. These results suggest that in nature, individual male stickleback exhibit robust parental behavioral types, and highly parental males are more attentive to their surroundings. Future studies are needed to examine the potential causes of individual variation in parental behavior in the field. PMID:25663736
Rubinov, Mikail; Cam-CAN; Henson, Richard N.
Resting-state functional connectivity, as measured by functional magnetic resonance imaging (fMRI), is often treated as a trait, used, for example, to draw inferences about individual differences in cognitive function, or differences between healthy or diseased populations. However, functional connectivity can also depend on the individual's mental state. In the present study, we examined the relative contribution of state and trait components in shaping an individual's functional architecture. We used fMRI data from a large, population-based human sample (N = 587, age 18–88 years), as part of the Cambridge Centre for Aging and Neuroscience (Cam-CAN), which were collected in three mental states: resting, performing a sensorimotor task, and watching a movie. Whereas previous studies have shown commonalities across mental states in the average functional connectivity across individuals, we focused on the effects of states on the pattern of individual differences in functional connectivity. We found that state effects were as important as trait effects in shaping individual functional connectivity patterns, each explaining an approximately equal amount of variance. This was true when we looked at aging, as one specific dimension of individual differences, as well as when we looked at generic aspects of individual variation. These results show that individual differences in functional connectivity consist of state-dependent aspects, as well as more stable, trait-like characteristics. Studying individual differences in functional connectivity across a wider range of mental states will therefore provide a more complete picture of the mechanisms underlying factors such as cognitive ability, aging, and disease. SIGNIFICANCE STATEMENT The brain's functional architecture is remarkably similar across different individuals and across different mental states, which is why many studies use functional connectivity as a trait measure. Despite these trait-like aspects, functional
Beißert, Hanna M; Hasselhorn, Marcus
This study investigates the relationship between intelligence and individual differences in children's moral development across a range of different moral transgressions. Taking up prior research that showed morality and intelligence to be related in adolescents and adults, the current study wants to test if these findings can be extended to younger children. The study was designed to address some of the shortcomings in prior research by examining young children aged between 6 years; 4 months and 8 years; 10 months, using a broad concept of moral development including emotional aspects and applying an approach that is closely connected to children's daily lives. Participants (N = 129) completed a standardized intelligence test and were presented four moral transgression stories to assess moral development. Results demonstrated that findings from prior research with adolescents or adults cannot simply be extended to younger participants. No significant correlations of moral development and intelligence were found for any of the presented stories. This provides first evidence that - at least in middle childhood - moral developmental status seems to be independent from children's general intelligence assessed by figural inductive reasoning tests.
Moon, Jungaa; Betts, Shawn; Anderson, John R
The current study investigated the effects of individual differences and workload on strategy adaptivity in a complex, dynamic task called the Space Fortress game (Donchin, 1989). Participants learned to use a strategy of flying a ship in circles around the fortress in a standard game environment. Once they mastered the strategy, they were assigned to different workload conditions and transferred to a nonstandard environment in which a strong wind was introduced that made it more difficult to achieve a circular orbit. About half of the participants continued with their prior circular strategy while the rest adopted a novel strategy that achieved comparable performance with less effort. With this novel strategy, rather than trying to complete orbits they flew into the wind and then allowed the wind to blow them back to achieve a pendulum-like path. Participants without a working-memory load were more likely to adopt the new strategy. Participants were also more likely to adopt the new strategy if their pattern of behavior exposed them more often to the potential of drifting with the wind. The results indicate that spontaneous changes in strategy occur when people are exposed to the potential of a new strategy and have the cognitive resources to understand its potential.
Goitein, Lara; James, Brent
Standardization of medical care through protocols, order sets, and other tools is increasingly a part of efforts to improve quality. The authors, a physician beginning a new position as director of a community hospital quality program and the chief quality officer of a health care system and director of a course in health care delivery improvement, discuss the benefits and risks of standardization in health care. Recommendations for responsible standardization are presented.
Lu, James; Kishida, Ken; De Asis Cruz, Josepheen; Lohrenz, Terry; Deering, Diane Treadwell; Beauchamp, Michael; Montague, P Read
Functional magnetic resonance imaging typically makes inferences about neural substrates of cognitive phenomena at the group level. We report the use of a single-stimulus BOLD response in the cingulate cortex that differentiates individual children with autism spectrum disorder from matched typically developing control children with sensitivity and specificity of 63.6% and 73.7% respectively. The approach consists of passive viewing of 'self' and 'other' faces from which an individual difference measure is derived from the BOLD response to the first 'self' image only; the method, penalized logistic regression, requires no averaging over stimulus presentations or individuals. These findings show that single-stimulus fMRI responses can be extracted from individual subjects and used profitably as a neural individual difference measure. The result suggests that single-stimulus fMRI can be developed to produce quantitative neural biomarkers for other developmental disorders and may even be useful in the rapid typing of cognition in healthy individuals.
Weiss, Michael J.; Lockwood, J. R.; McCaffrey, Daniel F.
In the "individually randomized group treatment" (IRGT) experimental design, individuals are first randomly assigned to a treatment arm or a control arm, but then within each arm, are grouped together (e.g., within classrooms/schools, through shared case managers, in group therapy sessions, through shared doctors, etc.) to receive…
Hepworth, Willie; Towler, Annette
This study examined the effects of individual differences variables (trait anger, self-control, negative affectivity, attitudes toward revenge, and attributional style) and charismatic leadership on incidents of workplace aggression in a sample of 213 employees from a wide range of organizations. Hierarchical multiple regression analyses indicated that the individual differences variables accounted for 27% of the variance in workplace aggression and that charismatic leadership accounted for an additional 3% after controlling for individual differences. In addition, psychological empowerment partially mediated the relationship between charismatic leadership and workplace aggression.
Boersma, Gretha J.; Tamashiro, Kellie L.
Exposure to prenatal stress alters the phenotype of the offspring in adulthood. When the prenatal and adult environments do not match, these alterations may induce pathology risk. There are, however, large individual differences in the effects of prenatal stress. While some individuals seem vulnerable, others appear to be relatively resistant to its effects. In this review we discuss potential mechanisms underlying these individual differences with a focus on animal models. Differences between rodent models selected for stress coping traits are discussed. In addition, the role of circulating factors, like glucocorticoids and cytokines, factors involved in brain development and influences of epigenetic and genetic factors in prenatal stress induced phenotype are covered. PMID:27589662
Walker, Stacy; Weidner, Thomas; Armstrong, Kirk J.
Context: Simulations and standardized patient (SP) encounters are used to provide clinical experiences for students. In athletic training, no research has examined the perceived educational benefits of these interventions. Objective: To explore athletic training students' perceptions regarding small group SP encounters and individual case-based…
... who serve as selection team members for the owner? 636.117 Section 636.117 Highways FEDERAL HIGHWAY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION ENGINEERING AND TRAFFIC OPERATIONS DESIGN-BUILD CONTRACTING General § 636.117 What conflict of interest standards apply to individuals who serve as selection team...
... who serve as selection team members for the owner? 636.117 Section 636.117 Highways FEDERAL HIGHWAY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION ENGINEERING AND TRAFFIC OPERATIONS DESIGN-BUILD CONTRACTING General § 636.117 What conflict of interest standards apply to individuals who serve as selection team...
Pons, Francisco; Lawson, Joanne; Harris, Paul L; de Rosnay, Marc
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 was explained by age alone and 27% by language ability alone. The results are discussed in terms of their theoretical and practical implications.
A new analysis of data from 15 cognitive tasks completed by 93 subjects with scores on the Cattell Culture Fair test show that differences in Cattell score systematically affected performance on some tasks more than on others. Implications for theories of local and global differences in mental ability are discussed. (SLD)
Asbury, Kathryn; Dunn, Judith F.; Pike, Alison; Plomin, Robert
Examined nonshared environmental (NSE) influences on twin preschoolers' behavior independent of genetics. Found that within-pair parenting differences correlated with monozygotic differences in behavior. For the extreme 10 percent of the parenting-discordant and behavior-discordant distributions, average NSE effect size was 11 percent, suggesting…
MacLean, Mary H.; Arnell, Karen M.; Cote, Kimberly A.
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…
Watson, Jason M.; Bunting, Michael F.; Poole, Bradley J.; Conway, Andrew R. A.
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…
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…
Although the L2 acquisition studies of Japanese particles "WA" and "GA" were investigated by many researchers (Sakamoto, 2000), they completely ignored learners' individual differences. Indeed, learners' individualities are important factors for the L2 learning (Lightbrown & Spada, 1999). Thus, this research explored whether learners' individual…
Coulombe, Patrick; Selig, James P.; Delaney, Harold D.
Researchers often collect longitudinal data to model change over time in a phenomenon of interest. Inevitably, there will be some variation across individuals in specific time intervals between assessments. In this simulation study of growth curve modeling, we investigate how ignoring individual differences in time points when modeling change over…
Schmiedek, Florian; Oberauer, Klaus; Wilhelm, Oliver; Suss, Heinz-Martin; Wittmann, Werner W.
The authors bring together approaches from cognitive and individual differences psychology to model characteristics of reaction time distributions beyond measures of central tendency. Ex-Gaussian distributions and a diffusion model approach are used to describe individuals' reaction time data. The authors identified common latent factors for each…
... Joint Report: Differences in Accounting and Capital Standards Among the Federal Banking Agencies; Report... of the U.S. Senate describing differences between the capital and accounting standards used by the... Regarding Differences in Accounting and Capital Standards Among the Federal Banking Agencies...
Sengupta, Sabyasachi; Krishnakumar, Subramanian; Sharma, Tarun; Gopal, Lingam; Khetan, Vikas
The International Retinoblastoma Staging Working Group (IRSWG) provided guidelines for tissue handling of eyes enucleated for retinoblastoma. We adopted these guidelines from January 2009. Reviewing histopathology slides between January 2006 and December 2010 we found significantly more number of eyes with massive choroidal, optic nerve, and anterior segment invasion by tumor cells in the post-IRSWG era. The guidelines provided by the IRSWG; in addition to being standardized; recognize more eyes with histopathologic risk factors compared to techniques applied in the past. This may translate to more children receiving adjuvant chemotherapy and contribute to reduced mortality rates in the future.
Verweij, Karin J H; Mosing, Miriam A; Ullén, Fredrik; Madison, Guy
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.
Galla, Brian M.; Plummer, Benjamin D.; White, Rachel E.; Meketon, David; D’Mello, Sidney K.; Duckworth, Angela L.
The current study reports on the development and validation of the Academic Diligence Task (ADT), designed to assess the tendency to expend effort on academic tasks which are tedious in the moment but valued in the long-term. In this novel online task, students allocate their time between solving simple math problems (framed as beneficial for problem solving skills) and, alternatively, playing Tetris or watching entertaining videos. Using a large sample of high school seniors (N = 921), the ADT demonstrated convergent validity with self-report ratings of Big Five conscientiousness and its facets, self-control and grit, as well as discriminant validity from theoretically unrelated constructs, such as Big Five extraversion, openness, and emotional stability, test anxiety, life satisfaction, and positive and negative affect. The ADT also demonstrated incremental predictive validity for objectively measured GPA, standardized math and reading achievement test scores, high school graduation, and college enrollment, over and beyond demographics and intelligence. Collectively, findings suggest the feasibility of online behavioral measures to assess noncognitive individual differences that predict academic outcomes. PMID:25258470
Whitty, Monica; Doodson, James; Creese, Sadie; Hodges, Duncan
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.
Murakami, Takashi; Kroonenberg, Pieter M.
Demonstrated how individual differences in semantic differential data can be modeled and assessed using three-mode models by studying the characterization of Chopin's "Preludes" by 38 Japanese college students. (SLD)
Tavor, I; Parker Jones, O; Mars, R B; Smith, S M; Behrens, T E; Jbabdi, S
When asked to perform the same task, different individuals exhibit markedly different patterns of brain activity. This variability is often attributed to volatile factors, such as task strategy or compliance. We propose that individual differences in brain responses are, to a large degree, inherent to the brain and can be predicted from task-independent measurements collected at rest. Using a large set of task conditions, spanning several behavioral domains, we train a simple model that relates task-independent measurements to task activity and evaluate the model by predicting task activation maps for unseen subjects using magnetic resonance imaging. Our model can accurately predict individual differences in brain activity and highlights a coupling between brain connectivity and function that can be captured at the level of individual subjects.
Community colleges must often analyze and report rates for outcomes, such as transfer to four-year colleges. A single, summary rate may be an invalid measure of its achievement in the transfer goal if the summary rate ignores the real difference in enrollment composition at different institutions. California's community colleges embody a very…
Inglis, Matthew; Mejia-Ramos, Juan Pablo; Weber, Keith; Alcock, Lara
In this article, we report a study in which 109 research-active mathematicians were asked to judge the validity of a purported proof in undergraduate calculus. Significant results from our study were as follows: (a) there was substantial disagreement among mathematicians regarding whether the argument was a valid proof, (b) applied mathematicians were more likely than pure mathematicians to judge the argument valid, (c) participants who judged the argument invalid were more confident in their judgments than those who judged it valid, and (d) participants who judged the argument valid usually did not change their judgment when presented with a reason raised by other mathematicians for why the proof should be judged invalid. These findings suggest that, contrary to some claims in the literature, there is not a single standard of validity among contemporary mathematicians.
CARDOSO, Mauricio de Almeida; de CASTRO, Renata Cristina Faria Ribeiro; LI AN, Tien; NORMANDO, David; GARIB, Daniela Gamba; CAPELOZZA FILHO, Leopoldino
Objective: The long face pattern is a facial deformity with increased anterior total facial height due to vertical excess of the lower facial third. Individuals with long face may present different degrees of severity in vertical excess, as well as malocclusions that are difficult to manage. The categorization of vertical excess is useful to determine the treatment prognosis. This survey assessed the distribution of ethnically different individuals with vertical excess according to three levels of severity and determined the prevalence of long face pattern. Material and Methods: The survey was comprised of 5,020 individuals of Brazilian ethnicity (2,480 females and 2,540 males) enrolled in middle schools in Bauru-SP, Brazil. The criterion for inclusion of individuals with vertically impaired facial relationships was based on lip incompetence, evaluated under natural light, in standing natural head position with the lips at rest. Once identified, the individuals were classified into three subtypes according to the severity: mild, moderate, and severe. Then the pooled sample was distributed according to ethnical background as White (Caucasoid), Black (African descent), Brown (mixed descent), Yellow (Asian descent) and Brazilian Indian (Brazilian native descent). The Chi-square (χ2) test was used (p<0.05) to compare the frequency ratios of individuals with vertically impaired facial relationships in the total sample and among different ethnicities, according to the three levels of severity. Results: The severe subtype was rare, except in Black individuals (7.32%), who also presented the highest relative frequency (45.53%) of moderate subtype, followed by Brown individuals (43.40%). In the mild subtype, Yellow (68.08%) and White individuals (62.21%) showed similar and higher relative frequency values. Conclusions: Black individuals had greater prevalence of long face pattern, followed by Brown, White and Yellow individuals. The prevalence of long face pattern was 14
Elfenbein, Hillary Anger; Curhan, Jared R.; Eisenkraft, Noah; Shirako, Aiwa; Baccaro, Lucio
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
Braten, Ivar; Olaussen, Bodil S.
This research examined whether distinct student profiles emerged from measures of interest, mastery goals, task value, and self-efficacy in samples of Norwegian student nurses and business administration students. Additionally, profile differences in self-reported strategy use and epistemological beliefs were examined, as well as changes in…
Saucier, Donald A; Webster, Russell J
Social vigilantism (SV) is an enduring individual difference that assesses the tendency of individuals to impress and propagate their "superior" beliefs onto others to correct others' more "ignorant" opinions. After establishing a reliable measure of SV, three studies showed that SV was associated with greater expressions of belief superiority (whether reacting to others holding dissimilar or similar beliefs) and greater resistance to persuasion (via increased rates of counterarguing and greater attitude stability after persuasion appeals) even after controlling for relevant individual differences (narcissism, dogmatism, psychological reactance, and need for cognition), as well as attitude importance and extremity. Thus, SV predicts expressions of belief superiority and resistance to persuasion above and beyond characteristics of the attitude and individual difference variables previously studied in the attitude literature. SV is a meaningful construct in increasing the understanding of persuasion, attitude resistance, and attitude dissemination that can be applied in a variety of psychological domains.
Artinger, Florian; Exadaktylos, Filippos; Koppel, Hannes; Sääksvuori, Lauri
Abundant evidence across the behavioral and social sciences suggests that there are substantial individual differences in pro-social behavior. However, little is known about the psychological mechanisms that underlie social preferences. This paper investigates whether empathy and Theory of Mind shape individual differences in pro-social behavior as conventionally observed in neutrally framed social science experiments. Our results show that individual differences in the capacity for empathy do not shape social preferences. The results qualify the role of Theory of Mind in strategic interaction. We do not only show that fair individuals exhibit more accurate beliefs about the behavior of others but that Theory of Mind can be effectively used to pursue both self-interest and pro-social goals depending on the principle objectives of a person. PMID:24743312
Artinger, Florian; Exadaktylos, Filippos; Koppel, Hannes; Sääksvuori, Lauri
Abundant evidence across the behavioral and social sciences suggests that there are substantial individual differences in pro-social behavior. However, little is known about the psychological mechanisms that underlie social preferences. This paper investigates whether empathy and Theory of Mind shape individual differences in pro-social behavior as conventionally observed in neutrally framed social science experiments. Our results show that individual differences in the capacity for empathy do not shape social preferences. The results qualify the role of Theory of Mind in strategic interaction. We do not only show that fair individuals exhibit more accurate beliefs about the behavior of others but that Theory of Mind can be effectively used to pursue both self-interest and pro-social goals depending on the principle objectives of a person.
Stevenson, Richard J; Mahmut, Mehmet; Rooney, Kieron
Interoception is the ability to perceive internal bodily states. This involves the detection and awareness of static and changing afferent signals from the viscera, motivational states, affective reactions, and associated cognitions. We examined whether there are individual differences in any or all of these aspects of ingestion-related interoception and their possible causes. Individual variation in almost all aspects of interoception was documented for hunger, fullness and thirst - including how participants use, prioritise and integrate visceral, motivational, affective and cognitive information. Individual differences may arise from multiple causes, including genetic influences, developmental changes hypothesised to result from child feeding practices, and from conditions such as depression, anxiety, eating disorders and certain subtypes of obesity. A nutritionally poor diet, and dietary restraint, may also affect ingestion-related interoception. Finally, certain forms of brain injury, notably to the medial temporal lobes are associated with impaired ingestion-related interoception. We conclude by examining the practical and theoretical consequences of these individual differences.
Tran, Steven; Nowicki, Magda; Muraleetharan, Arrujyan; Chatterjee, Diptendu; Gerlai, Robert
Variation among individuals may arise for several reasons, and may have diverse underlying mechanisms. Individual differences have been studied in a variety of species, but recently a new model organism has emerged in this field that offers both sophistication in phenotypical characterization and powerful mechanistic analysis. Recently, zebrafish, one of the favorites of geneticists, have been shown to exhibit consistent individual differences in baseline locomotor activity. In the current study, we further explore this finding and examine whether individual differences in locomotor activity correlate with anxiety-like behavioral measures and with levels of dopamine, serotonin and the metabolites of these neurotransmitters. In addition, we examine whether individual differences in locomotor activity are also associated with reactivity to the locomotor stimulant effects of and neurochemical responses to acute ethanol exposure (30min long, 1% v/v ethanol bath application). Principal component analyses revealed a strong association among anxiety-like responses, locomotor activity, serotonin and dopamine levels. Furthermore, ethanol exposure was found to abolish the locomotion-dependent anxiety-like behavioral and serotonergic responses suggesting that this drug also engages a common underlying pathway. Overall, our results provide support for an important role of the serotonergic system in mediating individual differences in anxiety-like responses and locomotor activity in zebrafish and for a minor modulatory role of the dopaminergic system.
Bridwell, David A; Hecker, Elizabeth A; Serences, John T; Srinivasan, Ramesh
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.
Robison, Matthew K; Unsworth, Nash
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.
Naber, Marnix; Vedder, Anneke; Brown, Stephen B R E; Nieuwenhuis, Sander
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.
Onwezen, M C; Van 't Riet, J; Dagevos, H; Sijtsema, S J; Snoek, H M
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.
... Performance for VOC Emissions From Petroleum Refinery Wastewater Systems § 60.693-1 Alternative standards for... semiannually thereafter for indication of cracks, gaps, or other problems that could result in VOC emissions... covered or enclosed in a manner so as to have no visual gaps or cracks in joints, seals, or other...
O'Hearn, Kirsten; Landau, Barbara
Williams syndrome (WS) is a developmental disorder associated with relatively spared verbal skills and severe visuospatial deficits. It has also been reported that individuals with WS are impaired at mathematics. We examined mathematical skills in persons with WS using the second edition of the Test of Early Mathematical Ability (TEMA-2), which…
Barker, Tyson V.; Troller-Renfree, Sonya; Pine, Daniel S.; Fox, Nathan A.
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 amongst 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. The current study 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 either high or low in social anxiety while they completed a flanker task in two contexts: alone and during social evaluation. Results revealed a significant interaction between social anxiety and context, such that the ERN was enhanced in a social relative to a non-social context only among high 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. PMID:25967929
Marklund, Staffan; Bolin, Malin; von Essen, Jan
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.
Barker, Tyson V; Troller-Renfree, Sonya; Pine, Daniel S; Fox, Nathan A
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.
Segal, Rebecca A; Kepler, Grace M; Kimbell, Julia S
Differences in nasal anatomy among human subjects may cause significant differences in respiratory airflow patterns and subsequent dosimetry of inhaled gases and particles in the respiratory tract. This study used computational fluid dynamics (CFD) to study inter-individual differences in nasal airflow among four healthy individuals. Magnetic resonance imaging (MRI) scans were digitized and nasal-surface-area-to-volume ratios (SAVR) were calculated for 15 adults. Two males and two females, representative of the range of SAVR values, were selected for flow analysis. Nasal CFD models were constructed for each subject by a semi-automated process that provided input to a commercial mesh generator to generate structured hexahedral meshes (Gambit, Fluent, Inc., Lebanon, NH, USA). Steady-state inspiratory laminar airflow at 15 L/min was calculated using commercial CFD software (FIDAP, Fluent, Inc., Lebanon, NH, USA). Streamline patterns, velocities, and helicity values were compared. In all subjects, the majority of flow passed through the middle and ventral regions of the nasal passages; however, the amount and location of swirling flow differed among individuals. Cross-sectional flow allocation analysis also indicated inter-individual differences. Laboratory water-dye experiments confirmed streamlines and velocity magnitudes predicted by the computational model. These results suggest that significant inter-individual differences exist in bulk airflow patterns in the nose.
Wong, Patrick C M; Morgan-Short, Kara; Ettlinger, Marc; Zheng, Jing
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.
Barrett, Lisa Feldman; Tugade, Michele M.; Engle, Randall W.
Dual-process theories of the mind are ubiquitous in psychology. A central principle of these theories is that behavior is determined by the interplay of automatic and controlled processing. In this article, the authors examine individual differences in the capacity to control attention as a major contributor to differences in working memory capacity (WMC). The authors discuss the enormous implications of this individual difference for a host of dual-process theories in social, personality, cognitive, and clinical psychology. In addition, the authors propose several new areas of investigation that derive directly from applying the concept of WMC to dual-process theories of the mind. PMID:15250813
Blagrove, Mark; Pace-Schott, Edward F
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.
Unterrainer, J M; Ruff, C C; Rahm, B; Kaller, C P; Spreer, J; Schwarzwald, R; Halsband, U
Several studies have attempted to identify the neuronal basis of sex differences in cognition. However, group differences in cognitive ability rather than genuine neurocognitive differences between the sexes may account for their results. Here, we compare with functional magnetic resonance imaging the relation between gender, individual task performance, and planning-related brain activation. Men and women preselected to display identical performance scores showed a strong relation between individual task performance and activation of the right dorsolateral prefrontal and right inferior parietal cortex activation during a visuospatial planning task. No gender-specific activations were found. However, a different pattern emerged when subjects had to execute the motor responses to the problems. Better performance was associated with right dorsolateral prefrontal and right parahippocampal activations, and females exhibited a stronger right hippocampal activation than males. These findings underline that an individual's performance level rather than his or her sex largely determines the neuronal activation patterns during higher-level cognition.
Mussel, Patrick; Ulrich, Natalie; Allen, John J. B.; Osinsky, Roman; Hewig, Johannes
Theta oscillations in the EEG have been shown to reflect ongoing cognitive processes related to mental effort. Here, we show that the pattern of theta oscillation in response to varying cognitive demands reflects stable individual differences in the personality trait epistemic motivation: Individuals with high levels of epistemic motivation recruit relatively more cognitive resources in response to situations possessing high, compared to low, cognitive demand; individuals with low levels do not show such a specific response. Our results provide direct evidence for the theory of the construct need for cognition and add to our understanding of the neural processes underlying theta oscillations. More generally, we provide an explanation how individual differences in personality traits might be represented on a neural level. PMID:27380648
Barrett, Lisa Feldman; Tugade, Michele M.; Engle, Randall W.
Dual-process theories of the mind are ubiquitous in psychology. A central principle of these theories is that behavior is determined by the interplay of automatic and controlled processing. In this article, the authors examine individual differences in the capacity to control attention as a major contributor to differences in working memory…
Weiss, Amy L., Ed.
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,…
Woltz, Dan J.; Shute, Valerie J.
Two studies involving 274 Air Force recruits and 163 college students, respectively, investigated the relationship between priming effects and declarative knowledge acquisition within repetitive practice models. Individual differences in repetition-priming effects uniquely predicted learning differences relative to other cognitive measures.…
Darcy, Maria; Lee, Debbiesiu; Tracey, Terence J. G.
Multicultural research has traditionally involved normative methodology and definitions of individual differences. To further our understanding of multicultural concerns, the authors urge researchers to broaden the repertoire of methods used in these inquiries. First, the authors highlight the differences among normative, idiographic, and…
Serna, Richard W.; Dube, William V.; McIlvane, William J.
Summarizes state-of-the-art approaches for assessing visual stimulus same/different judgments in individuals with severe intellectual disabilities. Methodological investigations indicate that one can obtain reliable same/different judgments with a variety of stimuli in virtually anyone for whom a basal score on the Peabody Picture Vocabulary Test…
In the setting of TCFL, this dissertation is an exploration of the dynamic development of individual differences and the learning and instruction environment. Major research studies done on motivation and learning strategies are reviewed. The motivation research in foreign language learning is introduced from three different perspectives in…
Scott, Brianna M.; Berman, Ashleigh F.
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…
Alderton, David L.; And Others
Adult performance on verbal analogy and classification problems was assessed in terms of outcomes of process execution. Process-outcomes measures accounted for overall performance and were related to ability. Problem forms differed in terms of which measures predicted individual differences. Common process-outcome measures showed highest…
Davison, Elizabeth N.; Turner, Benjamin O.; Miller, Michael B.; Carlson, Jean M.
Individual differences in brain functional networks may be related to complex personal identifiers, including health, age, and ability. Dynamic network theory has been used to identify properties of dynamic brain function from fMRI data, but the majority of analyses and findings remain at the level of the group. Here, we apply hypergraph analysis, a method from dynamic network theory, to quantify individual differences in brain functional dynamics. Using a summary metric derived from the hypergraph formalism—hypergraph cardinality—we investigate individual variations in two separate, complementary data sets. The first data set (“multi-task”) consists of 77 individuals engaging in four consecutive cognitive tasks. We observe that hypergraph cardinality exhibits variation across individuals while remaining consistent within individuals between tasks; moreover, the analysis of one of the memory tasks revealed a marginally significant correspondence between hypergraph cardinality and age. This finding motivated a similar analysis of the second data set (“age-memory”), in which 95 individuals, aged 18–75, performed a memory task with a similar structure to the multi-task memory task. With the increased age range in the age-memory data set, the correlation between hypergraph cardinality and age correspondence becomes significant. We discuss these results in the context of the well-known finding linking age with network structure, and suggest that hypergraph analysis should serve as a useful tool in furthering our understanding of the dynamic network structure of the brain. PMID:27880785
Robledo, Jodi; Donnellan, Anne M.; Strandt-Conroy, Karen
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 h 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. PMID:23162446
Sheldon, Signy; Amaral, Robert; Levine, Brian
Individuals differ in how they mentally imagine past events. When reminiscing about a past experience, some individuals remember the event accompanied by rich visual images, while others will remember it with few of these images. In spite of the implications that these differences in the use of imagery have to the understanding of human memory, few studies have taken them into consideration. We examined how imagery interference affecting event memory retrieval was differently modulated by spatial and object imagery ability. We presented participants with a series of video-clips depicting complex events. Participants subsequently answered true/false questions related to event, spatial, or feature details contained in the videos, while simultaneously viewing stimuli that interfered with visual imagery processes (dynamic visual noise; DVN) or a control grey screen. The impact of DVN on memory accuracy was related to individual differences in spatial imagery ability. Individuals high in spatial imagery were less accurate at recalling details from the videos when simultaneously viewing the DVN stimuli compared to those low in spatial imagery ability. This finding held for questions related to the event and spatial details but not feature details. This study advocates for the inclusion of individual differences when studying memory processes.
Grand, Jacob H.G.; Stawski, Robert S.; MacDonald, Stuart W.S.
Introduction Recent theorizing differentiates key constraints on cognition, including one’s current range of processing efficiency (i.e., flexibility or inconsistency) as well as the capacity to expand flexibility over time (i.e., plasticity). The present study uses intensive assessment of response time data to examine the interplay between markers of intraindividual variability (inconsistency) and gains across biweekly retest sessions (plasticity) in relation to age-related cognitive function. Method Participants included 304 adults (aged 64 to 92 years: M=74.02, SD=5.95) from Project MIND, a longitudinal burst design study assessing performance across micro and macro intervals (response latency trials, weekly bursts, annual retests). For two reaction time measures (choice RT and one-back choice RT), baseline measures of response time (RT) inconsistency (intraindividual standard deviation (ISD) across-trials at the first testing session) and plasticity (within-person performance gains in average RT across the 5 biweekly burst sessions) were computed, and then employed in linear mixed models as predictors of individual differences in cognitive function and longitudinal (6 year) rates of cognitive change. Results Independent of chronological age and years of education, higher RT inconsistency was associated uniformly with poorer cognitive function at baseline and with increased cognitive decline for measures of episodic memory and crystallized verbal ability. In contrast, predictive associations for plasticity were more modest for baseline cognitive function and were absent for 6-year cognitive change. Conclusions These findings underscore the potential utility of response times for articulating inconsistency and plasticity as dynamic predictors of cognitive function in older adults. PMID:26898536
Stevens, Martin; Lown, Alice E.; Wood, Louisa E.
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. PMID:25551233
Fox, Gregory J.; Benedetti, Andrea; Mitnick, Carole D.; Pai, Madhukar; Menzies, Dick
Background In the absence of randomized clinical trials, meta-analysis of individual patient data (IPD) from observational studies may provide the most accurate effect estimates for an intervention. However, confounding by indication remains an important concern that can be addressed by incorporating individual patient covariates in different ways. We compared different analytic approaches to account for confounding in IPD from patients treated for multi-drug resistant tuberculosis (MDR-TB). Methods Two antibiotic classes were evaluated, fluoroquinolones—considered the cornerstone of effective MDR-TB treatment—and macrolides, which are known to be safe, yet are ineffective in vitro. The primary outcome was treatment success against treatment failure, relapse or death. Effect estimates were obtained using multivariable and propensity-score based approaches. Results Fluoroquinolone antibiotics were used in 28 included studies, within which 6,612 patients received a fluoroquinolone and 723 patients did not. Macrolides were used in 15 included studies, within which 459 patients received this class of antibiotics and 3,670 did not. Both standard multivariable regression and propensity score-based methods resulted in similar effect estimates for early and late generation fluoroquinolones, while macrolide antibiotics use was associated with reduced treatment success. Conclusions In this individual patient data meta-analysis, standard multivariable and propensity-score based methods of adjusting for individual patient covariates for observational studies yielded produced similar effect estimates. Even when adjustment is made for potential confounding, interpretation of adjusted estimates must still consider the potential for residual bias. PMID:27022741
Olkoniemi, Henri; Ranta, Henri; Kaakinen, Johanna K
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 in working memory capacity (WMC), need for cognition (NFC), and cognitive-affective processing were measured. The results showed that the processing of metaphors was characterized by slow-down during first-pass reading of the utterances, whereas sarcasm produced mainly delayed effects in the eye movement records. Sarcastic utterances were also harder to comprehend than literal or metaphorical utterances as indicated by poorer performance in responses to inference questions. Individual differences in general cognitive factors (WMC and NFC) were related to the processing of metaphors, whereas individual differences in both general cognitive factors (WMC) as well as processing of emotional information were related to the processing of sarcasm. The results indicate that different forms of figurative language pose different cognitive demands to the reader, and show that reader characteristics play a prominent role in figurative language comprehension.
Sebag, M G; Korzenowski, C; Bernardes, A M; Vilela, A C
A study on laboratory scale to evaluate the environmental compatibility of electric arc furnace dust (EAFD) is reported in this article. EAFD, a waste by-product of the steel-making process, was generated on a steel plant located in Brazil. Different leaching tests, NBR10005 (Brazilian), AFNORX31-210 (French), JST-13 (Japanese), DIN38414-S4 (German), TCLP (American), and NEN 7343 (Netherland) were conducted. These leaching procedures are batch tests and are columns conducted in a way that an equilibrium condition should be achieved. The pH of the medium showed a crucial parameter governing the release of metals from the solid phase into solution. As the pH of the medium varies with the leachant used, this determines the dissolution of the elements. Zn, Pb, Mn, Cd, and Cu presented high leachability at NBR10005 procedures (acid pH). Except Pb and Cr, the leachability of all others metals in leaching tests with alkaline pH decreases with the increase of the pH. NBR10005 classifies the EAFD as a hazardous waste due to high concentration of Pb and Cd in leachate. The column tests are presented in the following order of leaching: Pb>Cr>Zn>Mn>Cu>Cd.
van Heeswijck, Torbjorn; Paquet, Catherine; Kestens, Yan; Thierry, Benoit; Morency, Catherine; Daniel, Mark
This study assessed relationships between built environmental exposures measured within components of individual activity spaces (i.e., travel origins, destinations and paths in-between), and use of active transportation in a metropolitan setting. Individuals (n=37,165) were categorised as using active or sedentary transportation based on travel survey data. Generalised Estimating Equations analysis was used to test relationships with active transportation. Strength and significance of relationships between exposures and active transportation varied for different components of the activity space. Associations were strongest when including travel paths in expression of the built environment. Land use mix and greenness were negatively related to active transportation.
Bshary, Andrea; Bshary, Redouan
Originally, evolutionary game theory typically predicted that optimal behaviour in a given situation is uniform or bimodal. However, the growing evidence that animals behave more variably while individuals may differ consistently in their behaviour, has led to the development of models that predict a distribution of strategies. Here we support the importance of such models in a study on a coral reef fish host–parasite system. Parasitic blennies (Plagiotremus sp.) regularly attack other fishes to bite off scales and mucus. Individuals of some victim species react to being bitten with punishing the parasite through aggressive chasing. Our field observations and laboratory experiments show that individual blennies differ markedly in how they incorporate being punished into their foraging decisions. We discuss how these differences may affect the payoff structure and hence the net effect of punishment on punishers and on the appearance of a public good for look-alikes. PMID:23029356
King, Adam C; Ranganathan, Rajiv; Newell, Karl M
Individual differences in learning a motor task are rarely assessed even though they can potentially contribute to our understanding of the problem of motor redundancy-i.e., how individuals can exploit multiple different strategies to realize the task goal. This study examined individual variations in the preferred movement strategy of a redundant motor task. Thirty-two participants performed a star tracing task on a digitizing tablet with the goal of minimizing a performance score that was given as feedback. The performance score was a weighted combination of spatial error and movement time, meaning that multiple strategies could yield the same score. A cluster analysis revealed three distinct groups of individuals based on their initial movement strategy preferences. These groups were not only different on their initial performance, but also exhibited differences in both local (trial-to-trial change) and global (average change) search strategies that were reflected through differential modification of spatial and temporal components. Overall, the results in this space-time task reveal that the intrinsic dynamics of the individual channel the initial exploratory solutions to learning a redundant motor task.
Silverstein, Peterson, and Perdue (1986) studied changes in curvaceousness of the models in Vogue magazine over time and found that curvaceousness was inversely correlated with American women's participation in higher education and the professions. In the present study, it was predicted that the male standard for women's bodily attractiveness would differ from the female standard and would change differently over time, based on evolutionary theory. Published data on the bodily curvaceousness of models in Playboy and Vogue and on Miss America winners were used to test this hypothesis. Although they did not differ on average, the male and female standards changed differently over time. There was less variation in the male standard, represented by Playboy and by Miss America winners, than in the female standard, represented by Vogue. Results suggest that cultural standards of attractiveness are influenced by an evolved psychology of mate selection that has implications for understanding changes in the standard of attractiveness and its relation to eating disorders.
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
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.
Bode, Nikolai W. F.; Delcourt, Johann
Taking in sufficient quantities of nutrients is vital for all living beings and in doing so, individuals interact with the local resource environment. Here, we focus explicitly on the interactions between feeding individuals and the resource landscape. In particular, we are interested in the emergent movement dynamics resulting from these interactions. We present an individual-based simulation model for the movement of populations in a resource landscape that allows us to vary the strength of the interactions mentioned above. The key assumption and novelty of our model is that individuals can cause the release of additional nutrients, as well as consuming them. Our model produces clear predictions. For example, we expect more tortuous individual movement paths and higher levels of aggregation in populations occupying homogeneous environments where individual movement makes more nutrients available. We also show how observed movement dynamics could change when local nutrient sources are depleted or when the population density increases. Our predictions are testable and qualitatively reproduce the different feeding behaviours observed in filter-feeding ducks, for example. We suggest that considering two-way interactions between feeding individuals and resource landscapes could help to explain fine-scale movement dynamics. PMID:24130748
Eisenberger, Robert; Lynch, Patrick; Aselage, Justin; Rohdieck, Stephanie
The authors report that beliefs favoring the reciprocation of unfavorable treatment form a unitary factor that is distinct from beliefs favoring the reciprocation of favorable treatment. Individual differences in endorsement of this negative reciprocity norm were related to (a) beliefs that people are generally malevolent; (b) inclination toward anger in everyday life; (c) anger, disagreement, and ridicule directed toward a new acquaintance who treated participants unfavorably; and (d) reduced anxiety, positive emotional engagement, and encouragement of a new acquaintance who treated participants favorably. These findings suggest that individual differences in endorsement of the negative norm of reciprocity influence the extent of vengeance.
Anderson, Matthew J; Williams, Sarah A; O'Brien, Edward H
When resting, flamingos often lay their heads along their backs. While in this position they must curve their necks to either the right or left of their midline. Observations of captive Caribbean flamingos at the Philadelphia Zoo (Philadelphia, PA, USA) were conducted in order to determine if individual birds would display consistent preferences in neck-resting position over multiple observations. While individual birds were shown to vary greatly in regards to the strength and direction of their preferences, a significant flock-level preference towards neck resting to the right was obtained. Analysis of individual flamingos revealed that 5 out of 17 birds displayed preferences that significantly differed from chance, with each of these birds preferring to rest their necks to the right. From the present data we can conclude that flamingos display behavioural laterality of neck-resting position at both the level of the group and that of the individual.
Gaksch, Martin; Jorde, Rolf; Grimnes, Guri; Joakimsen, Ragnar; Schirmer, Henrik; Wilsgaard, Tom; Mathiesen, Ellisiv B.; Njølstad, Inger; Løchen, Maja-Lisa; März, Winfried; Kleber, Marcus E.; Tomaschitz, Andreas; Grübler, Martin; Eiriksdottir, Gudny; Gudmundsson, Elias F.; Harris, Tamara B.; Cotch, Mary F.; Aspelund, Thor; Gudnason, Vilmundur; Rutters, Femke; Beulens, Joline W. J.; van ‘t Riet, Esther; Nijpels, Giel; Dekker, Jacqueline M.; Grove-Laugesen, Diana; Rejnmark, Lars; Busch, Markus A.; Mensink, Gert B. M.; Scheidt-Nave, Christa; Thamm, Michael; Swart, Karin M. A.; Brouwer, Ingeborg A.; Lips, Paul; van Schoor, Natasja M.; Sempos, Christopher T.; Durazo-Arvizu, Ramón A.; Škrabáková, Zuzana; Dowling, Kirsten G.; Cashman, Kevin D.; Kiely, Mairead; Pilz, Stefan
Background Vitamin D deficiency may be a risk factor for mortality but previous meta-analyses lacked standardization of laboratory methods for 25-hydroxyvitamin D (25[OH]D) concentrations and used aggregate data instead of individual participant data (IPD). We therefore performed an IPD meta-analysis on the association between standardized serum 25(OH)D and mortality. Methods In a European consortium of eight prospective studies, including seven general population cohorts, we used the Vitamin D Standardization Program (VDSP) protocols to standardize 25(OH)D data. Meta-analyses using a one step procedure on IPD were performed to study associations of 25(OH)D with all-cause mortality as the primary outcome, and with cardiovascular and cancer mortality as secondary outcomes. This meta-analysis is registered at ClinicalTrials.gov, number NCT02438488. Findings We analysed 26916 study participants (median age 61.6 years, 58% females) with a median 25(OH)D concentration of 53.8 nmol/L. During a median follow-up time of 10.5 years, 6802 persons died. Compared to participants with 25(OH)D concentrations of 75 to 99.99 nmol/L, the adjusted hazard ratios (with 95% confidence interval) for mortality in the 25(OH)D groups with 40 to 49.99, 30 to 39.99, and <30 nmol/L were 1.15 (1.00–1.29), 1.33 (1.16–1.51), and 1.67 (1.44–1.89), respectively. We observed similar results for cardiovascular mortality, but there was no significant linear association between 25(OH)D and cancer mortality. There was also no significantly increased mortality risk at high 25(OH)D levels up to 125 nmol/L. Interpretation In the first IPD meta-analysis using standardized measurements of 25(OH)D we observed an association between low 25(OH)D and increased risk of all-cause mortality. It is of public health interest to evaluate whether treatment of vitamin D deficiency prevents premature deaths. PMID:28207791
Medeiros, Joyse; Duñabeitia, Jon Andoni
The present study explores the role of individual differences in polymorphemic word recognition. Participants completed a masked priming lexical decision experiment on suffixed words in which targets could be preceded by suffix-related words (words sharing the same suffix) or by affixed primes with a different suffix. Participants also completed a monomorphemic word lexical decision and were divided in two groups (fast and slow readers) according to their performance in this task. When the suffix priming data were analyzed taking into consideration participants' reading speed as a proxy for their greater reliance on orthography or on semantics, a significant interaction between reading speed and the magnitude of the masked suffix priming effects emerged. Only slow participants showed significant priming effects, whereas faster participants showed negligible masked suffix priming effects. These results demonstrate that different reading profiles modulate the access to morphological information in a qualitatively different manner and that individual differences in reading determine the manner in which polymorphemic words are processed.
McCollough, Cynthia H
Dose management in medical imaging is about using the right dose for the specific patient and the specific diagnostic task; since patients and diagnostic tasks vary widely, the applied doses must also vary widely. Thus, a large amount of the variation observed in the computed tomography (CT) doses applied in medical imaging is appropriate. However, unacceptable sources of variations also exist. For similar sized patients and similar diagnostic tasks, variations in the applied doses should be small. It is the responsibility of the medical professionals in the imaging community, therefore, to ensure appropriate variations while minimizing unacceptable variations. That is, imaging professionals must make it standard practice to optimize scan parameters in a way that is specific to both patient size and diagnostic task.
Wyer, Natalie A; Martin, Douglas; Pickup, Tracey; Macrae, C Neil
Recent research suggests that individuals with relatively weak global precedence (i.e., a smaller propensity to view visual stimuli in a configural manner) show a reduced face inversion effect (FIE). Coupled with such findings, a number of recent studies have demonstrated links between an advantage for feature-based processing and the presentation of traits associated with autism among the general population. The present study sought to bridge these findings by investigating whether a relationship exists between the possession of autism-associated traits (i.e., as indicated by individuals'"autism quotient" [(AQ) and the size of the FIE. Participants completed an on-line study in which the AQ was measured prior to a standard face recognition task where half of the faces were inverted at test. The results confirmed that higher AQ levels were predictive of smaller FIEs. Implications for a common underlying factor relating to processing orientation are discussed.
Boos, Moritz; Seer, Caroline; Lange, Florian; Kopp, Bruno
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. PMID:27303323
Kanai, Ryota; Bahrami, Bahador; Rees, Geraint
Social cues conveyed by the human face, such as eye gaze direction, are evaluated even before they are consciously perceived. While there is substantial individual variability in such evaluation, its neural basis is unknown. Here we asked whether individual differences in preconscious evaluation of social face traits were associated with local variability in brain structure. Adult human participants (n = 36) monocularly viewed faces varying in dominance and trustworthiness, which were suppressed from awareness by a dynamic noise pattern shown to the other eye. The time taken for faces to emerge from suppression and become visible (t2e) was used as a measure of potency in competing for visual awareness. Both dominant and untrustworthy faces resulted in slower t2e than neutral faces, with substantial individual variability in these effects. Individual differences in t2e were correlated with gray matter volume in right insula for dominant faces, and with gray matter volume in medial prefrontal cortex, right temporoparietal junction and bilateral fusiform face area for untrustworthy faces. Thus, individual differences in preconscious social processing can be predicted from local brain structure, and separable correlates for facial dominance and untrustworthiness suggest distinct mechanisms of preconscious processing. PMID:25193945
Stopher, Katie V; Pemberton, Josephine M; Clutton-Brock, Tim H; Coulson, Tim
Variation between individuals is an essential component of natural selection and evolutionary change, but it is only recently that the consequences of persistent differences between individuals on population dynamics have been considered. In particular, few authors have addressed whether interactions exist between individual quality and environmental variation. In part, this is due to the difficulties of collecting sufficient data, but also the challenge of defining individual quality. Using a long-established study population of red deer, Cervus elaphus, inhabiting the North Block of the Isle of Rum, and three quality measures, this paper investigates how differences in maternal quality affect variation in birth body mass and date, as population density varies, and how this differs depending on the sex of the offspring and the maternal quality measure used. Significant interactions between maternal quality, measured as a hind's total contribution to population growth, and population density are reported for birth mass, but only for male calves. Analyses using dominance or age at primiparity to define maternal quality showed no significant interactions with population density, highlighting the difficulties of defining a consistent measure of individual quality. PMID:18522909
Getov, Spas; Kanai, Ryota; Bahrami, Bahador; Rees, Geraint
Social cues conveyed by the human face, such as eye gaze direction, are evaluated even before they are consciously perceived. While there is substantial individual variability in such evaluation, its neural basis is unknown. Here we asked whether individual differences in preconscious evaluation of social face traits were associated with local variability in brain structure. Adult human participants (n = 36) monocularly viewed faces varying in dominance and trustworthiness, which were suppressed from awareness by a dynamic noise pattern shown to the other eye. The time taken for faces to emerge from suppression and become visible (t2e) was used as a measure of potency in competing for visual awareness. Both dominant and untrustworthy faces resulted in slower t2e than neutral faces, with substantial individual variability in these effects. Individual differences in t2e were correlated with gray matter volume in right insula for dominant faces, and with gray matter volume in medial prefrontal cortex, right temporoparietal junction and bilateral fusiform face area for untrustworthy faces. Thus, individual differences in preconscious social processing can be predicted from local brain structure, and separable correlates for facial dominance and untrustworthiness suggest distinct mechanisms of preconscious processing.
Stopher, Katie V; Pemberton, Josephine M; Clutton-Brock, Tim H; Coulson, Tim
Variation between individuals is an essential component of natural selection and evolutionary change, but it is only recently that the consequences of persistent differences between individuals on population dynamics have been considered. In particular, few authors have addressed whether interactions exist between individual quality and environmental variation. In part, this is due to the difficulties of collecting sufficient data, but also the challenge of defining individual quality. Using a long-established study population of red deer, Cervus elaphus, inhabiting the North Block of the Isle of Rum, and three quality measures, this paper investigates how differences in maternal quality affect variation in birth body mass and date, as population density varies, and how this differs depending on the sex of the offspring and the maternal quality measure used. Significant interactions between maternal quality, measured as a hind's total contribution to population growth, and population density are reported for birth mass, but only for male calves. Analyses using dominance or age at primiparity to define maternal quality showed no significant interactions with population density, highlighting the difficulties of defining a consistent measure of individual quality.
Guayasamin, Olivia L; Couzin, Iain D; Miller, Noam Y
An individual's behavioural phenotype is a combination of its unique behavioural propensities and its responsiveness to environmental variation, also known as behavioural plasticity. In social species, we must not only explore how individuals respond to variations in the physical environment but also how they react to changes in their social environment. A growing body of work has demonstrated that the behavioural heterogeneity of a group can alter its responsiveness, decision making, and fitness. Whether an individual is more or less extreme than a partner - what we term its 'relative personality' - may also alter individual behavioural responses. We determined exploratory tendencies of individual zebrafish (Danio rerio) and then constructed pairs with varying differences in 'relative personality' to determine the effect of differences between partners on behavioural plasticity. We find that relative personality, but not the magnitude of the difference between partners, is the most important determinant of behavioural plasticity across social treatments. Despite this overall effect, pairs of fish exhibited no predictable leader-follower interactions, suggesting that details of the experimental paradigm may be important in shaping social dynamics.
Chen, Siyu; Tanaka, Shigefumi; Oyakawa, Chisako; Roh, Sanggun; Sato, Shusuke
We examined individual differences in serum oxytocin concentrations (OT) of calves, and assessed whether these differences were correlated with their dams' milk and serum OT. Eight Holstein (H), nine Japanese Shorthorn (JS), and six Japanese Black (JB) calves were examined. Blood was collected three times during the first month in H calves, while their dams' blood was collected three times prior to parturition. Milk was collected twice after parturition from H cows. Blood from JS and JB calves were collected at 1 and 4 months old, while of their dams only once before parturition. Serum OT in H calves at 7 days old was significantly correlated with that at 30 days. Serum OT of JS calves at 1 month old was significantly correlated to that at 4 months, while of JB calves was also positively correlated (r = 0.70). Serum OT of calves showed significant individual differences in each breed. Serum OT of calves was not correlated with the milk OT of dams, except for 3-day-old calves that fed on their dams' milk. We concluded that although serum OT differed among individuals, this difference was stable within each individual and not affected by the serum OT of the dams.
Ormel, Johan; Aleman, André
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
Background The literature on social dilemmas and punishment focuses on the behaviour of the punisher. However, to fully explain the effect of punishment on cooperation, it is important to understand the psychological mechanisms influencing the behaviour of those who expect to be punished. This paper examines whether the expectation of punishment, rather than the implementation of punishment is sufficient to prevent individuals from free riding. Individual differences in the punishment sensitivity have been linked to both threat responses (flight, fight, fear system, or the FFFS) and to the response to the uncertainty of punishment (BIS-anxiety).The paper, therefore, examines if individual differences in BIS-anxiety and FFFS can explain some of the variability in free riding in the face of implemented and non-implemented punishment. Methods Participants took part in a series of one-shot Public Goods Games (PGGs) facing two punishment conditions (implemented and non-implemented) and two standard non-punishment PGGs. The punishment was implemented as a centralized authority punishment (i.e., if one participant contributed less than their group members, they were automatically fined). Individual contribution levels and presence/absence of zero contributions indexed free riding. Individual differences in behavioural inhibition were assessed. Results Individuals contributed more under the threat of punishment (both implemented and non-implemented). However, individuals contributed less when the punishment was not implemented compared to when it was. Those scoring high in BIS-anxiety contributed more when the punishment expectations were not implemented. This effect was not observed for FFFS. Conclusion Supporting previous research, punishment had a powerful effect in increasing contribution levels in the PGGs. However, when expected punishment was not implemented, individual differences in punishment sensitivity, specifically in BIS-anxiety, were related to fewer
Rödel, Heiko G; Bautista, Amando; Roder, Manuel; Gilbert, Caroline; Hudson, Robyn
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
Bernard, Larry C
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.
Bush, Wilma Jo; And Others
The relationship between patterns of learning ability and the amount learned under different instructional conditions was studied. Scores for each of 44 Air Force trainees were obtained on several standardized tests of achievement and ability. Each subject then participated and was tested in five learning situations: (1) listening to taped…
Choi, Inyong; Wang, Le; Bharadwaj, Hari; Shinn-Cunningham, Barbara
Many studies have shown that attention modulates the cortical representation of an auditory scene, emphasizing an attended source while suppressing competing sources. Yet, individual differences in the strength of this attentional modulation and their relationship with selective attention ability are poorly understood. Here, we ask whether differences in how strongly attention modulates cortical responses reflect differences in normal-hearing listeners' selective auditory attention ability. We asked listeners to attend to one of three competing melodies and identify its pitch contour while we measured cortical electroencephalographic responses. The three melodies were either from widely separated pitch ranges ("easy trials"), or from a narrow, overlapping pitch range ("hard trials"). The melodies started at slightly different times; listeners attended either the leading or lagging melody. Because of the timing of the onsets, the leading melody drew attention exogenously. In contrast, attending the lagging melody required listeners to direct top-down attention volitionally. We quantified how attention amplified auditory N1 response to the attended melody and found large individual differences in the N1 amplification, even though only correctly answered trials were used to quantify the ERP gain. Importantly, listeners with the strongest amplification of N1 response to the lagging melody in the easy trials were the best performers across other types of trials. Our results raise the possibility that individual differences in the strength of top-down gain control reflect inherent differences in the ability to control top-down attention.
Raz, Naftali; Ghisletta, Paolo; Rodrigue, Karen M; Kennedy, Kristen M; Lindenberger, Ulman
The human brain changes with age. However, the rate and the trajectories of change vary among the brain regions and among individuals, and the reasons for these differences are unclear. In a sample of healthy middle-aged and older adults, we examined mean volume change and individual differences in the rate of change in 12 regional brain volumes over approximately 30 months. In addition to the baseline assessment, there were two follow-ups, 15 months apart. We observed significant average shrinkage of the hippocampus, entorhinal cortex, orbital-frontal cortex, and cerebellum in each of the intervals. Shrinkage of the hippocampus accelerated with time, whereas shrinkage of the caudate nucleus, prefrontal subcortical white matter, and corpus callosum emerged only at the second follow-up. Throughout both assessment intervals, the mean volumes of the lateral prefrontal and primary visual cortices, putamen, and pons did not change. Significant individual differences in shrinkage rates were observed in the lateral prefrontal cortex, the cerebellum, and all the white matter regions throughout the study, whereas additional regions (medial-temporal structures, the insula, and the basal ganglia) showed significant individual variation in change during the second follow-up. No individual variability was noted in the change of orbital frontal and visual cortices. In two white matter regions, we were able to identify factors associated with individual differences in brain shrinkage. In corpus callosum, shrinkage rate was greater in persons with hypertension, and in the pons, women and carriers of the ApoEepsilon4 allele exhibited declines not noted in the whole sample.
Raz, Naftali; Ghisletta, Paolo; Rodrigue, Karen M.; Kennedy, Kristen M.; Lindenberger, Ulman
The human brain changes with age. However, the rate and the trajectories of change vary among the brain regions and among individuals, and the reasons for these differences are unclear. In a sample of healthy middle-aged and older adults, we examined mean volume change and individual differences in the rate of change in 12 regional brain volumes over approximately 30 months. In addition to the baseline assessment, there were two follow-ups, 15 months apart. We observed significant average shrinkage of the hippocampus, entorhinal cortex, orbital–frontal cortex, and cerebellum in each of the intervals. Shrinkage of the hippocampus accelerated with time, whereas shrinkage of the caudate nucleus, prefrontal subcortical white matter, and corpus callosum emerged only at the second follow-up. Throughout both assessment intervals, the mean volumes of the lateral prefrontal and primary visual cortices, putamen, and pons did not change. Significant individual differences in shrinkage rates were observed in the lateral prefrontal cortex, the cerebellum, and all the white matter regions throughout the study, whereas additional regions (medial–temporal structures, the insula, and the basal ganglia) showed significant individual variation in change during the second follow-up. No individual variability was noted in the change of orbital frontal and visual cortices. In two white matter regions, we were able to identify factors associated with individual differences in brain shrinkage. In corpus callosum, shrinkage rate was greater in persons with hypertension, and in the pons, women and carriers of the ApoEε4 allele exhibited declines not noted in the whole sample. PMID:20298790
Peterson, Matthew F; Lin, Jing; Zaun, Ian; Kanwisher, Nancy
Recent laboratory studies have found large, stable individual differences in the location people first fixate when identifying faces, ranging from the brows to the mouth. Importantly, this variation is strongly associated with differences in fixation-specific identification performance such that individuals' recognition ability is maximized when looking at their preferred location (Mehoudar, Arizpe, Baker, & Yovel, 2014; Peterson & Eckstein, 2013). This finding suggests that face representations are retinotopic and individuals enact gaze strategies that optimize identification, yet the extent to which this behavior reflects real-world gaze behavior is unknown. Here, we used mobile eye trackers to test whether individual differences in face gaze generalize from lab to real-world vision. In-lab fixations were measured with a speeded face identification task, while real-world behavior was measured as subjects freely walked around the Massachusetts Institute of Technology campus. We found a strong correlation between the patterns of individual differences in face gaze in the lab and real-world settings. Our findings support the hypothesis that individuals optimize real-world face identification by consistently fixating the same location and thus strongly constraining the space of retinotopic input. The methods developed for this study entailed collecting a large set of high-definition, wide field-of-view natural videos from head-mounted cameras and the viewer's fixation position, allowing us to characterize subjects' actually experienced real-world retinotopic images. These images enable us to ask how vision is optimized not just for the statistics of the "natural images" found in web databases, but of the truly natural, retinotopic images that have landed on actual human retinae during real-world experience.
Jackson, Simon A.; Kleitman, Sabina; Howie, Pauline; Stankov, Lazar
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
Imperio, Caesar G; McFalls, Ashley J; Colechio, Elizabeth M; Masser, Dustin R; Vrana, Kent E; Grigson, Patricia S; Freeman, Willard M
Heroin addiction is a disease of chronic relapse that harms the individual through devaluation of personal responsibilities in favor of finding and using drugs. Only some recreational heroin users devolve into addiction but the basis of these individual differences is not known. We have shown in rats that avoidance of a heroin-paired taste cue reliably identifies individual animals with greater addiction-like behavior for heroin. Here rats received 5min access to a 0.15% saccharin solution followed by the opportunity to self-administer either saline or heroin for 6h. Large Suppressors of the heroin-paired taste cue displayed increased drug escalation, motivation for drug, and drug loading behavior compared with Small Suppressors. Little is known about the molecular mechanisms of these individual differences in addiction-like behavior. We examined the individual differences in mRNA expression in the nucleus accumbens (NAc) of rats that were behaviorally stratified by addiction-like behavior using next-generation sequencing. We hypothesized that based on the avoidance of the drug-paired cue there will be a unique mRNA profile in the NAc. Analysis of strand-specific whole genome RNA-Seq data revealed a number of genes differentially regulated in NAc based on the suppression of the natural saccharine reward. Large Suppressors exhibited a unique mRNA prolife compared to Saline controls and Small Suppressors. Genes related to immunity, neuronal activity, and behavior were differentially expressed among the 3 groups. In total, individual differences in avoidance of a heroin-paired taste cue are associated with addiction-like behavior along with differential NAc gene expression.
Jackson, Simon A; Kleitman, Sabina; Howie, Pauline; Stankov, Lazar
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.
Woollams, Anna M.; Lambon Ralph, Matthew A.; Madrid, Gaston; Patterson, Karalyn E.
The extent to which meaning is involved in reading aloud has proven an area of longstanding debate, and current computational models differ on this dimension. The connectionist triangle model proposes that normal individuals rely on semantic information for correct reading of words with atypical spelling-sound relationships, but to varying degrees. This proposed individual difference would account for the varying stage of decline at which patients with semantic dementia first show the reading impairment known as surface dyslexia. Recent neuroimaging data has provided validation of this view, showing that individual differences in degree of semantic reliance during exception word reading predict the amount of activation in left anterior temporal regions associated with semantic processing. This study aimed to establish the cognitive correlates of individual differences in semantic reliance during exception word reading. Experiment 1 used a subgrouping approach with 32 participants and found larger imageability and semantic priming effects specifically for exception word reading amongst high relative to low semantic reliance readers. High semantic reliance readers also tended to read nonwords more slowly than low semantic reliance readers. A second experiment used a regression approach with 129 readers and confirmed the relationship of degree of semantic reliance both to imageability effects in exception word reading and speed of nonword reading. Further, while the performance of the higher semantic readers revealed no significant association with semantic processing tasks, there was a negative relationship with rhyme processing tasks. We therefore speculate that differences in phonological abilities may be responsible for varying degrees of semantic reliance in reading aloud. This proposal accords with the results of functional imaging showing that higher semantic reliance during exception word reading corresponds to lower activation in left pre-central gyrus, an
Ambrose, Joseph P; Wijeakumar, Sobanawartiny; Buss, Aaron T; Spencer, John P
Visual working memory (VWM) is a key cognitive system that enables people to hold visual information in mind after a stimulus has been removed and compare past and present to detect changes that have occurred. VWM is severely capacity limited to around 3-4 items, although there are robust individual differences in this limit. Importantly, these individual differences are evident in neural measures of VWM capacity. Here, we capitalized on recent work showing that capacity is lower for more complex stimulus dimension. In particular, we asked whether individual differences in capacity remain consistent if capacity is shifted by a more demanding task, and, further, whether the correspondence between behavioral and neural measures holds across a shift in VWM capacity. Participants completed a change detection (CD) task with simple colors and complex shapes in an fMRI experiment. As expected, capacity was significantly lower for the shape dimension. Moreover, there were robust individual differences in behavioral estimates of VWM capacity across dimensions. Similarly, participants with a stronger BOLD response for color also showed a strong neural response for shape within the lateral occipital cortex, intraparietal sulcus (IPS), and superior IPS. Although there were robust individual differences in the behavioral and neural measures, we found little evidence of systematic brain-behavior correlations across feature dimensions. This suggests that behavioral and neural measures of capacity provide different views onto the processes that underlie VWM and CD. Recent theoretical approaches that attempt to bridge between behavioral and neural measures are well positioned to address these findings in future work.
Ambrose, Joseph P.; Wijeakumar, Sobanawartiny; Buss, Aaron T.; Spencer, John P.
Visual working memory (VWM) is a key cognitive system that enables people to hold visual information in mind after a stimulus has been removed and compare past and present to detect changes that have occurred. VWM is severely capacity limited to around 3–4 items, although there are robust individual differences in this limit. Importantly, these individual differences are evident in neural measures of VWM capacity. Here, we capitalized on recent work showing that capacity is lower for more complex stimulus dimension. In particular, we asked whether individual differences in capacity remain consistent if capacity is shifted by a more demanding task, and, further, whether the correspondence between behavioral and neural measures holds across a shift in VWM capacity. Participants completed a change detection (CD) task with simple colors and complex shapes in an fMRI experiment. As expected, capacity was significantly lower for the shape dimension. Moreover, there were robust individual differences in behavioral estimates of VWM capacity across dimensions. Similarly, participants with a stronger BOLD response for color also showed a strong neural response for shape within the lateral occipital cortex, intraparietal sulcus (IPS), and superior IPS. Although there were robust individual differences in the behavioral and neural measures, we found little evidence of systematic brain-behavior correlations across feature dimensions. This suggests that behavioral and neural measures of capacity provide different views onto the processes that underlie VWM and CD. Recent theoretical approaches that attempt to bridge between behavioral and neural measures are well positioned to address these findings in future work. PMID:27147986
Brewer, Gene A.; Unsworth, Nash
The current study examined individual differences in the effects of retrieval from long-term memory (i.e., the testing effect). The effects of retrieving from memory make tested information more accessible for future retrieval attempts. Despite the broad applied ramifications of such a potent memorization technique there is a paucity of research…
Unsworth, Nash; Brewer, Gene A.; Spillers, Gregory J.
The present study examined individual differences in everyday cognitive failures assessed by diaries. A large sample of participants completed various cognitive ability measures in the laboratory. Furthermore, a subset of these participants also recorded everyday cognitive failures (attention, retrospective memory, and prospective memory failures)…
Laatsch, Chelsea N; Durbin-Johnson, Blythe P; Rocke, David M; Mukwana, Sophie; Newland, Abby B; Flagler, Michael J; Davis, Michael G; Eigenheer, Richard A; Phinney, Brett S; Rice, Robert H
Hair from different individuals can be distinguished by physical properties. Although some data exist on other species, examination of the individual molecular differences within the human hair shaft has not been thoroughly investigated. Shotgun proteomic analysis revealed considerable variation in profile among samples from Caucasian, African-American, Kenyan and Korean subjects. Within these ethnic groups, prominent keratin proteins served to distinguish individual profiles. Differences between ethnic groups, less marked, relied to a large extent on levels of keratin associated proteins. In samples from Caucasian subjects, hair shafts from axillary, beard, pubic and scalp regions exhibited distinguishable profiles, with the last being most different from the others. Finally, the profile of isolated hair cuticle cells was distinguished from that of total hair shaft by levels of more than 20 proteins, the majority of which were prominent keratins. The cuticle also exhibited relatively high levels of epidermal transglutaminase (TGM3), accounting for its observed low degree of protein extraction by denaturants. In addition to providing insight into hair structure, present findings may lead to improvements in differentiating hair from various ethnic origins and offer an approach to extending use of hair in crime scene evidence for distinguishing among individuals.
MaClean, Mary H; Arnell, Karen M
The attentional blink (AB) is observed when report accuracy for a second target (T2) is reduced if T2 is presented within approximately 500 ms of a first target (T1), but accuracy is relatively unimpaired at longer T1-T2 separations. The AB is thought to represent a transient cost of attending to a target, and reliable individual differences have been observed in its magnitude. Some models of the AB have suggested that cognitive control contributes to production of the AB, such that greater cognitive control is associated with larger AB magnitudes. Performance-monitoring functions are thought to modulate the strength of cognitive control, and those functions are indexed by event-related potentials in response to both endogenous and exogenous performance evaluation. Here we examined whether individual differences in the amplitudes to internal and external response feedback predict individual AB magnitudes. We found that electrophysiological responses to externally provided performance feedback, measured in two different tasks, did predict individual differences in AB magnitude, such that greater feedback-related N2 amplitudes were associated with larger AB magnitudes, regardless of the valence of the feedback.
Klein, Christoph; Arend, Isabel C.; Beauducel, Andre; Shapiro, Kimron L.
The failure to correctly report two targets ("T[subscript 1]", "T[subscript 2]") that follow each other in close temporal proximity has been called the "attentional blink" (AB). The AB has, so far, mainly been studied using experimental approaches. The present studies investigated individual differences in AB performance, revealing (among further…
Tagarelli, Kaitlyn M.; Ruiz, Simón; Vega, José Luis Moreno; Rebuschat, Patrick
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.…
Shamir, Adina; Mevarech, Zemira R.; Gida, Carmit
This study investigated the effectiveness of assessing young children's meta-cognition in different contexts (i.e., individual learning (IL), peer assisted learning (PAL) and self-reports). Additionally, the contributions of declarative and procedural meta-cognition in IL and PAL, TOM and language ability on children's cognitive performance…
Al-Hendawi, Maha; Reed, Evelyn
Individual differences in temperament can be protective or risk factors that may enhance or interfere with children's healthy development and educational success. This study examined the concurrent and predictive relationships between temperament, school adjustment, and academic achievement in children at-risk. Seventy-seven children at-risk, ages…
Wang, Yi-Shun; Lin, Hsin-Hui; Liao, Yi-Wen
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…
Del Missier, Fabio; Mäntylä, Timo; Hansson, Patrik; Bruine de Bruin, Wändi; Parker, Andrew M.; Nilsson, Lars-Göran
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,…
King, Laurel A.
Understanding the user and customizing the interface to augment cognition and usability are goals of human computer interaction research and design. Yet, little is known about the influence of individual visual-verbal information presentation preferences on visual navigation and screen element usage. If consistent differences in visual navigation…
Jackson, Simon A.; Kleitman, Sabina
Decision-making is a complex process that is largely studied from an experimental perspective or in specific organizational contexts. As such, no generalizable framework exists with which to study decision-making from an individual differences perspective for predictive/selection purposes. By generalising a context-specific decision model proposed…
Arnaudova, Inna; Krypotos, Angelos-Miltiadis; Effting, Marieke; Boddez, Yannick; Kindt, Merel; Beckers, Tom
Complex fear learning procedures might be better suited than the common differential fear-conditioning paradigm for detecting individual differences related to vulnerability for anxiety disorders. Two such procedures are the blocking procedure and the protection-from-overshadowing procedure. Their comparison allows for the examination of discriminatory fear learning under conditions of ambiguity. The present study examined the role of individual differences in such discriminatory fear learning. We hypothesized that heightened trait anxiety would be related to a deficit in discriminatory fear learning. Participants gave US-expectancy ratings as an index for the threat value of individual CSs following blocking and protection-from-overshadowing training. The difference in threat value at test between the protected-from-overshadowing conditioned stimulus (CS) and the blocked CS was negatively correlated with scores on a self-report tension-stress scale that approximates facets of generalized anxiety disorder (GAD), the Depression Anxiety Stress Scale-Stress (DASS-S), but not with other individual difference variables. In addition, a behavioral test showed that only participants scoring high on the DASS-S avoided the protected-from-overshadowing CS. This observed deficit in discriminatory fear learning for participants with high levels of tension-stress might be an underlying mechanism for fear overgeneralization in diffuse anxiety disorders such as GAD.
Lopez-Zamora, Miguel; Luque, Juan L.; Alvarez, Carlos J.; Cobos, Pedro L.
This article examines the relationship between individual differences in speech perception and sublexical/phonological processing in reading. We used an auditory phoneme identification task in which a /ba/-/pa/ syllable continuum measured sensitivity to classify participants into three performance groups: poor, medium, and good categorizers. A…
Discusses individual differences between users of information systems that can influence search performance, and describes two experiments that addressed user-centered design of information systems. Highlights include interaction between cognitive abilities and design features; compensation and capitalization perspectives; recall and precision;…
Veldre, Aaron; Andrews, Sally
Although there is robust evidence that skilled readers of English extract and use orthographic and phonological information from the parafovea to facilitate word identification, semantic preview benefits have been elusive. We sought to establish whether individual differences in the extraction and/or use of parafoveal semantic information could…
Arnaudova, Inna; Krypotos, Angelos-Miltiadis; Effting, Marieke; Boddez, Yannick; Kindt, Merel; Beckers, Tom
Complex fear learning procedures might be better suited than the common differential fear-conditioning paradigm for detecting individual differences related to vulnerability for anxiety disorders. Two such procedures are the blocking procedure and the protection-from-overshadowing procedure. Their comparison allows for the examination of discriminatory fear learning under conditions of ambiguity. The present study examined the role of individual differences in such discriminatory fear learning. We hypothesized that heightened trait anxiety would be related to a deficit in discriminatory fear learning. Participants gave US-expectancy ratings as an index for the threat value of individual CSs following blocking and protection-from-overshadowing training. The difference in threat value at test between the protected-from-overshadowing conditioned stimulus (CS) and the blocked CS was negatively correlated with scores on a self-report tension-stress scale that approximates facets of generalized anxiety disorder (GAD), the Depression Anxiety Stress Scale-Stress (DASS-S), but not with other individual difference variables. In addition, a behavioral test showed that only participants scoring high on the DASS-S avoided the protected-from-overshadowing CS. This observed deficit in discriminatory fear learning for participants with high levels of tension-stress might be an underlying mechanism for fear overgeneralization in diffuse anxiety disorders such as GAD. PMID:23755030
Parks, James P.; And Others
This study examined the differences between Type A and B individuals and their hardiness. Although it is thought to be an independent risk factor for coronary heart disease, the role of Type A behavior in other disease processes or general health has not been established. Because Type A has been hypothesized to be a maladaptive coping strategy…
Friedman, Naomi P; Miyake, Akira
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.
Llewellyn, Nicole; Rudolph, Karen D.
Peer victimization is a known risk factor for various forms of maladjustment; however, the specific type of maladjustment may depend on individual differences in youth. This 2-wave longitudinal study examined the hypothesis that social approach-avoidance motivation, together with sex, would moderate the contribution of 3rd-grade victimization to…
William Domhoff, G; Schneider, Adam
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.
Sparks, Richard L.
In this article, I describe studies conducted over 25 years with secondary and post-secondary L2 learners in the United States. The evidence from these studies shows that there are important connections between students' early L1 skills and their L2 aptitude and L2 proficiency and that individual differences in students' L1 skills in elementary…
Kim, Sun-A; Packard, Jerome; Christianson, Kiel; Anderson, Richard C.; Shin, Jeong-Ah
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…
Lusk, Danielle L.; Evans, Amber D.; Jeffrey, Thomas R.; Palmer, Keith R.; Wikstrom, Chris S.; Doolittle, Peter E.
Research in multimedia learning lacks an emphasis on individual difference variables, such as working memory capacity (WMC). The effects of WMC and the segmentation of multimedia instruction were examined by assessing the recall and application of low (n = 66) and high (n = 67) working memory capacity students randomly assigned to either a…
Graham, Bronwyn M.; Richardson, Rick
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…
Ackerman, Phillip L.
A program of theoretical and empirical research focusing on the ability determinants of individual differences in skill acquisition is reviewed. An integrative framework for information-processing and cognitive ability determinants of skills is reviewed, along with principles for ability-skill relations. Experimental manipulations were used to…
Ngo, Chi T.; Weisberg, Steven M.; Newcombe, Nora S.; Olson, Ingrid R.
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…
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Chen, June L.; Sung, Connie; Pi, Sukyeong
Young adults with autism spectrum disorders (ASD) often experience employment difficulties. Using Rehabilitation Service Administration data (RSA-911), this study investigated the service patterns and factors related to the employment outcomes of individuals with ASD in different age groups. Hierarchical logistic regression analyses were conducted…
Galbraith, Vicki; Gardner, R. C.
The bibliography contains 64 annotated references to journal articles and other sources of information about individual difference correlates of second language achievement. The journal articles appeared between 1984 and 1987. Where available, abstracts contained in the original articles are used; these are marked with asterisks. Entries are coded…
Silliman, Elaine R.
In honor of Dr. Katherine Butler's extraordinary leadership of "Topics in Language Disorders," this article takes up her 1982 challenge to reach toward greater understanding of individual differences in the use of oral and written language by children with language learning disability. The article focuses on 3 interconnected dimensions of learning…
Hertzog, Christopher; von Oertzen, Timo; Ghisletta, Paolo; Lindenberger, Ulman
We evaluated the statistical power of single-indicator latent growth curve models to detect individual differences in change (variances of latent slopes) as a function of sample size, number of longitudinal measurement occasions, and growth curve reliability. We recommend the 2 degree-of-freedom generalized test assessing loss of fit when both…
Bernhardt, Boris C; Klimecki, Olga M; Leiberg, Susanne; Singer, Tania
Previous functional imaging studies have shown key roles of the dorsal anterior insula (dAI) and anterior midcingulate cortex (aMCC) in empathy for the suffering of others. The current study mapped structural covariance networks of these regions and assessed the relationship between networks and individual differences in empathic responding in 94 females. Individual differences in empathy were assessed through average state measures in response to a video task showing others' suffering, and through questionnaire-based trait measures of empathic concern. Overall, covariance patterns indicated that dAI and aMCC are principal hubs within prefrontal, temporolimbic, and midline structural covariance networks. Importantly, participants with high empathy state ratings showed increased covariance of dAI, but not aMCC, to prefrontal and limbic brain regions. This relationship was specific for empathy and could not be explained by individual differences in negative affect ratings. Regarding questionnaire-based empathic trait measures, we observed a similar, albeit weaker modulation of dAI covariance, confirming the robustness of our findings. Our analysis, thus, provides novel evidence for a specific contribution of frontolimbic structural covariance networks to individual differences in social emotions beyond negative affect.
Diamond, Lisa M.; Fagundes, Christopher P.; Cribbet, Matthew R.
The present study tested whether individual differences in autonomic nervous system functioning interact with environmental risk factors to predict adolescents' psychosocial functioning. The authors assessed skin conductance and respiratory sinus arrhythmia at rest and during laboratory stressors in 110 14-year-olds. Subsequently, adolescents and…
Ashouri, Amir Farzad; Fotovatnia, Zahra
This study investigated learners' beliefs about translation and the effect of two variables of individual differences, risk taking and tolerance of ambiguity, on the mentioned variable. The participants of the study were 120 EFL learners homogenized through Oxford Placement Test. They received three questionnaires on translation belief,…
Haier, Richard J.; White, Nathan S.; Alkire, Michael T.
Administered Raven's Advanced Progressive Matrices to 22 adults and measured cerebral glucose activity as subjects viewed videos on 2 occasions. Data provide evidence that individual differences in intelligence correlate with brain function even when the brain is engaged in non-reasoning tasks. (SLD)
Describes a study that investigated individual differences in the construction of mental models of recursion in LOGO programming. The learning process was investigated from the perspective of Norman's mental models theory and employed diSessa's ontology regarding distributed, functional, and surrogate mental models, and the Luria model of brain…
Sandi, Carmen; Cordero, M. Isabel; Merino, Jose J.; Kruyt, Nyika D.; Regan, Ciaran M.; Murphy, Keith J.
The polysialylated neural cell adhesion molecule (PSA-NCAM) has been implicated in activity-dependent synaptic remodeling and memory formation. Here, we questioned whether training-induced modulation of PSA-NCAM expression might be related to individual differences in spatial learning abilities. At 12 h posttraining, immunohistochemical analyses…
Miller, A. Eve; Watson, Jason M.; Strayer, David L.
Neuroscience suggests that the anterior cingulate cortex (ACC) is responsible for conflict monitoring and the detection of errors in cognitive tasks, thereby contributing to the implementation of attentional control. Though individual differences in frontally mediated goal maintenance have clearly been shown to influence outward behavior in…
Cools, Eva; Bellens, Kim
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.…
Rudolph, Karen D.; Troop-Gordon, Wendy; Granger, Douglas A.
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…
Doolittle, Peter E.; Mariano, Gina J.
The present study examined the effects of individual differences in working memory capacity (WMC) on learning from an historical inquiry multimedia tutorial in stationary versus mobile learning environments using a portable digital media player (i.e., iPod). Students with low (n = 44) and high (n = 40) working memory capacity, as measured by the…
Mercier, Julie; Pivneva, Irina; Titone, Debra
We investigated whether individual differences in inhibitory control relate to bilingual spoken word recognition. While their eye movements were monitored, native English and native French English-French bilinguals listened to English words (e.g., "field") and looked at pictures corresponding to the target, a within-language competitor…
Gelman, Susan A.; Ware, Elizabeth A.; Kleinberg, Felicia; Manczak, Erika M.; Stilwell, Sarah M.
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…
Rounds, James B., Jr.
Two studies, one cross-sectional and the other longitudinal, examined individual differences in subjective perceptions of disabilities. In study 1, 37 (22 unsuccessful and 15 successful) applicants to and 29 (12 first year and 17 second year) graduate students in a rehabilitation counseling master's degree program judged the similarity of all…
Seo, Young Seok
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…
Carazo, Pau; Noble, Daniel W. A.; Chandrasoma, Dani; Whiting, Martin J.
Understanding individual differences in cognitive performance is a major challenge to animal behaviour and cognition studies. We used the Eastern water skink (Eulamprus quoyii) to examine associations between exploration, boldness and individual variability in spatial learning, a dimension of lizard cognition with important bearing on fitness. We show that males perform better than females in a biologically relevant spatial learning task. This is the first evidence for sex differences in learning in a reptile, and we argue that it is probably owing to sex-specific selective pressures that may be widespread in lizards. Across the sexes, we found a clear association between boldness after a simulated predatory attack and the probability of learning the spatial task. In contrast to previous studies, we found a nonlinear association between boldness and learning: both ‘bold’ and ‘shy’ behavioural types were more successful learners than intermediate males. Our results do not fit with recent predictions suggesting that individual differences in learning may be linked with behavioural types via high–low-risk/reward trade-offs. We suggest the possibility that differences in spatial cognitive performance may arise in lizards as a consequence of the distinct environmental variability and complexity experienced by individuals as a result of their sex and social tactics. PMID:24619443
Scrimin, Sara; Altoè, Gianmarco; Moscardino, Ughetta; Pastore, Massimiliano; Mason, Lucia
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…
Leaf, Justin B.; Dale, Stephanie; Kassardjian, Alyne; Tsuji, Kathleen H.; Taubman, Mitchell; McEachin, John J.; Leaf, Ronald B.; Oppenheim-Leaf, Misty L.
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,…
Westenberg, P. Michiel; Gullone, Eleonora; Bokhorst, Caroline L.; Heyne, David A.; King, Neville J.
Using cross-sectional (N=910) and longitudinal (N = 261) data from Gullone and King's (1993,1997) studies of normal fear in children and adolescents aged 7 to 18 years, the normative developmental pattern of social evaluation fear and the continuity of individual differences were investigated. Participants' responses were analysed according to two…
Sparks, Glenn G.; Spirek, Melissa M.
Reports on two studies summarizing recent advances in the study of behavioral dispositions by detailing the activation-arousal framework. Uses the Miller Behavioral Style Scale to measure individual differences in activation/arousal while viewing a negative emotional film segment and media coverage of the explosion of the space shuttle…
Hanulikova, Adriana; Dediu, Dan; Fang, Zhou; Basnakova, Jana; Huettig, Falk
Many learners of a foreign language (L2) struggle to correctly pronounce newly learned speech sounds, yet many others achieve this with apparent ease. Here we explored how a training study of learning complex consonant clusters at the very onset of L2 acquisition can inform us about L2 learning in general and individual differences in particular.…
Cantwell, Robert H.; Scevak, Jill J.; Bourke, Sid; Holbrook, Allyson
Understanding how candidates cope with the demands of PhD candidature is important for institutions, supervisors and candidates. Individual differences in affective and metacognitive disposition were explored in 263 PhD candidates from two Australian universities. Several questionnaires relating to affective and metacognitive beliefs were…