Longitudinal Genetic Analysis for Loneliness in Dutch Twins

AbstractIn previous studies we obtained evidence that variation in loneliness has a genetic component. Based on adult twin data, the heritability estimate for loneliness, which was assessed as an ordinal trait, was 48%. These analyses were done on loneliness scores averaged over items (‘I feel lonely’ and ‘Nobody loves me’) and over time points. In this article we present a longitudinal analysis of loneliness data assessed in 5 surveys (1991 through 2002) in Dutch twins (N = 8389) for the two separate items of the loneliness scale. From the longitudinal growth modeling it was found sufficient to have non-zero variance for the intercept only, while the other effects (linear, quadratic and cubic slope) had zero variance. For the item ‘I feel lonely’ we observed an increasing age trend up to age 30, followed by a decline to age 50. Heritability for individual differences in the intercept was estimated at 77%. For the item ‘Nobody loves me’ no significant trend over age was seen; the heritability of the intercept was estimated at 70%.

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Stable individual differences in strategies within, but not between, visual search tasks

10.31234/osf.io/bqa5v ◽

2018 ◽

Cited By ~ 3

Author(s):

Alasdair D F Clarke ◽

Jessica Irons ◽

Warren James ◽

Andrew B. Leber ◽

Amelia R. Hunt

Keyword(s):

Individual Differences ◽

Visual Search ◽

Search Task ◽

The Other ◽

Search Performance ◽

Search Tasks ◽

And Performance ◽

Context Specific ◽

Test Retest Reliability ◽

Over Time

A striking range of individual differences has recently been reported in three different visual search tasks. These differences in performance can be attributed to strategy, that is, the efficiency with which participants control their search to complete the task quickly and accurately. Here we ask if an individual's strategy and performance in one search task is correlated with how they perform in the other two. We tested 64 observers in the three tasks mentioned above over two sessions. Even though the test-retest reliability of the tasks is high, an observer's performance and strategy in one task did not reliably predict their behaviour in the other two. These results suggest search strategies are stable over time, but context-specific. To understand visual search we therefore need to account not only for differences between individuals, but also how individuals interact with the search task and context. These context-specific but stable individual differences in strategy can account for a substantial proportion of variability in search performance.

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Stable individual differences in strategies within, but not between, visual search tasks

Quarterly Journal of Experimental Psychology ◽

10.1177/1747021820929190 ◽

2020 ◽

pp. 174702182092919 ◽

Cited By ~ 1

Author(s):

Alasdair DF Clarke ◽

Jessica L Irons ◽

Warren James ◽

Andrew B Leber ◽

Amelia R Hunt

Keyword(s):

Individual Differences ◽

Visual Search ◽

Search Task ◽

The Other ◽

Retest Reliability ◽

Search Tasks ◽

And Performance ◽

Context Specific ◽

Test Retest Reliability ◽

Over Time

A striking range of individual differences has recently been reported in three different visual search tasks. These differences in performance can be attributed to strategy, that is, the efficiency with which participants control their search to complete the task quickly and accurately. Here, we ask whether an individual’s strategy and performance in one search task is correlated with how they perform in the other two. We tested 64 observers and found that even though the test–retest reliability of the tasks was high, an observer’s performance and strategy in one task was not predictive of their behaviour in the other two. These results suggest search strategies are stable over time, but context-specific. To understand visual search, we therefore need to account not only for differences between individuals but also how individuals interact with the search task and context.

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Different Strains of Mycobacterium tuberculosis Cause Various Spectrums of Disease in the Rabbit Model of Tuberculosis

Infection and Immunity ◽

10.1128/iai.71.10.6004-6011.2003 ◽

2003 ◽

Vol 71 (10) ◽

pp. 6004-6011 ◽

Cited By ~ 101

Author(s):

Yukari C. Manabe ◽

Arthur M. Dannenberg ◽

Sandeep K. Tyagi ◽

Christine L. Hatem ◽

Mark Yoder ◽

...

Keyword(s):

Mycobacterium Tuberculosis ◽

Genetic Analysis ◽

Mycobacterium Bovis ◽

Rabbit Model ◽

The Other ◽

Animal Host ◽

Cavitary Disease ◽

Visible Lesion ◽

Different Strains ◽

Over Time

ABSTRACT The rabbit model of tuberculosis has been used historically to differentiate between Mycobacterium tuberculosis and Mycobacterium bovis based on their relative virulence in this animal host. M. tuberculosis infection in market rabbits is cleared over time, whereas infection with M. bovis results in chronic, progressive, cavitary disease leading to death. Because of the innate resistance of commercial rabbits to M. tuberculosis, 320 to 1,890 log-phase, actively growing inhaled bacilli were required to form one grossly visible pulmonary tubercle at 5 weeks. The range of inhaled doses required to make one tubercle allows us to determine the relative pathogenicities of different strains. Fewer inhaled organisms of the M. tuberculosis Erdman strain were required than of M. tuberculosis H37Rv to produce a visible lesion at 5 weeks. Furthermore, with the Erdman strain, only 7 of 15 rabbits had healed lesions at 16 to 18 weeks; among the other animals, two had chronic, progressive cavitary disease, a phenotype usually seen only with M. bovis infection. Genotypic investigation of the Erdman strain with an H37Rv-based microarray identified gene differences in the RD6 region. Southern blot and PCR structural genetic analysis showed significant differences between M. tuberculosis strains in this region. Correlation of the relative pathogenicity, including disease severity, in the rabbit model with the strain genotype may help identify stage-specific M. tuberculosis genes important in human disease.

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Publication Trends in Personality and Individual Differences, 1980–2018

10.31234/osf.io/c6qya ◽

2020 ◽

Author(s):

Gregory D. Webster ◽

Imani Turner ◽

Joy Ellen Losee ◽

Elizabeth Mahar ◽

Val Wongsomboon

Keyword(s):

Individual Differences ◽

Linear Increase ◽

Dark Triad ◽

Personality Psychology ◽

Time Points ◽

Innovative Methods ◽

Title Word ◽

Trends Over Time ◽

Emerging Topics ◽

Over Time

An analysis including 679 articles from the journal Personality and Individual Differences (PAID) investigated trends from 1980 to 2018. Time periods were separated into three groups: 1980–1984, 2000, and 2018. First, the number of title words per article was examined, which showed a linear increase over time. Second, the most frequent words per PAID article were investigated over time. The most frequent title words across three time points were, predictably, “personality,” “individual,” and “differences.” Title word frequencies also unveiled trends such as the adoption of the Big Five and Dark Triad traits, and an increasing interest in latent modeling of personality traits. Third, we explored the number of authors per article, which showed a linear increase across the three time points. Lastly, we identified the most-cited articles from 1980 to 2018. Themes from some of the most influential articles included scale development, scale and construct comparisons, review articles, and innovative methods. Although personality psychology has some constant themes over time, these findings suggest that it continues to be an influential and dynamic field open to incorporating emerging topics and evolving trends over time.

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Ignoring individual differences in times of assessment in growth curve modeling

International Journal of Behavioral Development ◽

10.1177/0165025415577684 ◽

2015 ◽

Vol 40 (1) ◽

pp. 76-86 ◽

Cited By ~ 7

Author(s):

Patrick Coulombe ◽

James P. Selig ◽

Harold D. Delaney

Keyword(s):

Individual Differences ◽

Growth Curve ◽

Type I Error ◽

Growth Curve Modeling ◽

Type I ◽

Residual Variance ◽

Change Over Time ◽

Time Points ◽

Curve Modeling ◽

Over Time

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 time relates to convergence and admissibility of solutions, bias in estimates of parameters, efficiency, power to detect change over time, and Type I error rate. We manipulated magnitude of the individual differences in assessment times, distribution of assessment times, magnitude of change over time, number of time points, and sample size. In contrast to the correct analysis, ignoring individual differences in time points frequently led to inadmissible solutions, especially with few time points and small samples, regardless of the specific magnitude of individual differences that were ignored. Mean intercept and slope were generally estimated without bias. Ignoring individual differences in time points sometimes yielded overestimated intercept and slope variances and underestimated intercept–slope covariance and residual variance. Parameter efficiency as well as power and Type I error rates for the linear slope were unaffected by the type of analysis.

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Immediate Self-information is Prioritized over Expanded Self-information across Temporal, Social, Spatial, and Probability Domains

10.31234/osf.io/thu3j ◽

2020 ◽

Author(s):

Hyunji Kim ◽

Arnd Florack

Keyword(s):

Decision Making ◽

Individual Differences ◽

Cognitive Ability ◽

Basic Structure ◽

The Self ◽

Self Concept ◽

Time Points ◽

Distant Location ◽

Underlying Mechanisms ◽

Over Time

People construct self-representation beyond the experiential self and the self-concept can expand to interpersonal as well as intrapersonal dimensions. The cognitive ability to project oneself onto expanded selves in different time points and places plays a crucial role in planning and decision making situations. However, no research to date has shown evidence explaining the early mechanism of how processing the experiential self-information differs from processing the expanded self-information across temporal, social, spatial, and probability domains. We report novel effects showing a systematic information prioritization towards the experiential selves (i.e., The self that is now, here, and with highest certainty) compared to the expanded selves (i.e., The self that is in the future, at a distant location, and with lower certainty; Experiments 1a, 2, and 3). Implicit prioritization biases lasted over time (Experiment 1b; i.e., 4 months) indicating a trait-like more than a state-like measure of individual differences. Different biases, however, did not consistently correlate with each other (Experiments 1a to 3) suggesting separate underlying mechanisms. We discuss potential links to the basic structure of self-representation and individual differences for implications.

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Individual differences and consistency in maternal talk style during joint story encoding and retrospection: Associations with children’s long-term recall

International Journal of Behavioral Development ◽

10.1080/01650250042000122 ◽

2001 ◽

Vol 25 (1) ◽

pp. 27-36 ◽

Cited By ~ 16

Author(s):

Jason Low ◽

Kevin Durkin

Keyword(s):

Individual Differences ◽

Memory Performance ◽

Story Recall ◽

Time Points ◽

Parents And Children ◽

Children's Memory ◽

Relative Differences ◽

Over Time

The manner in which parents and children reminisce about personal events has received increasing attention over the last decade as it has important implications for children’s memory performance. How individual differences in maternal talk style relate to children’s story recall is less clear. The present study examined stylistic consistencies and changes between initial mother-child online encoding of a story event (T1) and between mother-child retrospections about the same story event 4 months later (T2), 8 months later (T3), and 12 months later (T4). Twenty-four children, 72-months-old at T1, and their mothers participated. During story encoding, mothers could be classi” ed as high or low elaborative. Relative differences between these maternal groups endured over time. Children of high elaborative mothers contributed more story information than children of low elaborative mothers at each of the four time points. Constraints and implications of the study are discussed.

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Immediate self-information is prioritized over expanded self-information across temporal, social, spatial, and probability domains

Quarterly Journal of Experimental Psychology ◽

10.1177/17470218211004208 ◽

2021 ◽

pp. 174702182110042

Author(s):

Hyunji Kim ◽

Arnd Florack

Keyword(s):

Decision Making ◽

Individual Differences ◽

Cognitive Ability ◽

Basic Structure ◽

The Self ◽

Self Concept ◽

Time Points ◽

Distant Location ◽

Underlying Mechanisms ◽

Over Time

People construct self-representation beyond the experiential self and the self-concept can expand to interpersonal as well as intrapersonal dimensions. The cognitive ability to project oneself onto expanded selves in different time points and places plays a crucial role in planning and decision-making situations. However, no research to date has shown evidence explaining the early mechanism of how processing the experiential self-information differs from processing the expanded self-information across temporal, social, spatial, and probability domains. We report novel effects showing a systematic information prioritization toward the experiential selves (i.e., the self that is now, here, and with highest certainty) compared to the expanded selves (i.e., the self that is in the future, at a distant location, and with lower certainty; Experiments 1a, 2, and 3). Implicit prioritization biases lasted over time (Experiment 1b; i.e., 4 months) indicating a trait-like more than a state-like measure of individual differences. Different biases, however, did not consistently correlate with each other (Experiments 1a to 3) suggesting separate underlying mechanisms. We discuss potential links to the basic structure of self-representation and individual differences for implications.

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The Reliability of Retrieval-Induced Forgetting

European Psychologist ◽

10.1027/1016-9040/a000040 ◽

2012 ◽

Vol 17 (1) ◽

pp. 1-10 ◽

Cited By ~ 6

Author(s):

Rosalind Potts ◽

Robin Law ◽

John F. Golding ◽

David Groome

Keyword(s):

Individual Differences ◽

Recognition Test ◽

Laboratory Tests ◽

The Other ◽

Clinical Factors ◽

Test Items ◽

T1 And T2 ◽

Test Materials ◽

Induced Forgetting

Retrieval-induced forgetting (RIF) refers to the finding that the retrieval of an item from memory impairs the retrieval of related items. The extent to which this impairment is found in laboratory tests varies between individuals, and recent studies have reported an association between individual differences in the strength of the RIF effect and other cognitive and clinical factors. The present study investigated the reliability of these individual differences in the RIF effect. A RIF task was administered to the same individuals on two occasions (sessions T1 and T2), one week apart. For Experiments 1 and 2 the final retrieval test at each session made use of a category-cue procedure, whereas Experiment 3 employed category-plus-letter cues, and Experiment 4 used a recognition test. In Experiment 2 the same test items that were studied, practiced, and tested at T1 were also studied, practiced, and tested at T2, but for the remaining three experiments two different item sets were used at T1 and T2. A significant RIF effect was found in all four experiments. A significant correlation was found between RIF scores at T1 and T2 in Experiment 2, but for the other three experiments the correlations between RIF scores at T1 and T2 failed to reach significance. This study therefore failed to find clear evidence for reliable individual differences in RIF performance, except where the same test materials were used for both test sessions. These findings have important implications for studies involving individual differences in RIF performance.

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Investment Traits and Intelligence in Adulthood

Journal of Individual Differences ◽

10.1027/1614-0001/a000101 ◽

2013 ◽

Vol 34 (2) ◽

pp. 82-89 ◽

Cited By ~ 5

Author(s):

Sophie von Stumm

Keyword(s):

Individual Differences ◽

Personality Traits ◽

Fluid Intelligence ◽

Need For Cognition ◽

Openness To Experience ◽

Intelligence Tests ◽

Crystallized Intelligence ◽

New Knowledge ◽

The Relationship ◽

Over Time

Intelligence-as-knowledge in adulthood is influenced by individual differences in intelligence-as-process (i.e., fluid intelligence) and in personality traits that determine when, where, and how people invest their intelligence over time. Here, the relationship between two investment traits (i.e., Openness to Experience and Need for Cognition), intelligence-as-process and intelligence-as-knowledge, as assessed by a battery of crystallized intelligence tests and a new knowledge measure, was examined. The results showed that (1) both investment traits were positively associated with intelligence-as-knowledge; (2) this effect was stronger for Openness to Experience than for Need for Cognition; and (3) associations between investment and intelligence-as-knowledge reduced when adjusting for intelligence-as-process but remained mostly significant.

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