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    Interindividual Differences in Behavior and Cognition Predicted by

    Local Brain Structure: A Strictly Confirmatory Replication Study.

    Authors: Eric-Jan Wagenmakers, Birte Forstmann, Luam Belay, Wouter Boekel.

    Abstract

    We seek to conduct a purely confirmatory replication study of eleven studies that have

    previously reported an association between behavior and structural properties of the brain.

    In order to ensure that our replication is strictly confirmatory, this document outlines the

    details of our experimental design and plan for data analysis.

    Background

    Recently, much interest has concerned the relation between brain structure on the one

    hand and behavior and/or cognition on the other hand. For instance, Kanai and colleagues

    (2012) found that individuals with greater gray matter volume in specific brain regions have

    larger online social networks (i.e., more Facebook friends) than individuals with less gray

    matter volume in these areas. Here, we propose to conduct a strictly confirmatoryreplication study for eleven recently published studies, each of which associated certain

    structural properties of the human brain with certain behavioral measures. Specifically, the

    behavioral measures relate to behavioral activation (Xu et al., 2012), control over speed and

    accuracy in perceptual decision making (Forstmann et al., 2010), percept duration in

    perceptual rivalry (Kanai et al., 2010, 2011a), components of attention (i.e., executive

    control and alerting; Westlye et al., 2011), aspects of social cognition (i.e., (online) social

    network size; Bickart et al., 2011; Kanai et al., 2012), distractibility (Kanai et al., 2011d),

    political orientation (Kanai et al., 2011c), moral values (Lewis et al., 2012), and empathy

    (Banissy et al., 2012).

    In order to ensure that the data analyses and hypothesis tests are strictly

    confirmatory, this document describes the eleven experiments and associated analyses that

    we aim to replicate. At the time of publishing, 36 participants have been tested but none of

    the data are analyzed or inspected. The study-specific information is preceded by the

    General Methods and Analyses section describing the participants, the general procedure,

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    the MRI data acquisition, the MRI preprocessing and analysis, and finally the Bayesian

    hypothesis test for correlations.

    Note that we leave open the possibility of conducting additional exploratory analyses.

    However, any exploratory analyses will be clearly labeled as such.

    General Methods and Analyses

    Local gray matter volume and cortical thickness will be quantified by means of voxel-based

    morphometry (VBM) and white matter integrity will be quantified by diffusion tensor

    imaging (DTI) and probabilistic tractography.

    Participants. Participants are recruited from a 43-participant MRI study that was recently

    conducted by our own research group. These participants are young, healthy undergraduate

    students (mean age = 20.12, SD = 1.73) from the University of Amsterdam with normal or

    corrected-to-normal vision. Participants received a monetary compensation for their time and

    effort.

    A subset of 36 students has been tested for the present study, but data have not been

    analyzed or inspected, yet. The earlier MRI experiment featured extensive measurements of

    brain structure, and hence the additional effort involved in replicating the eleven studiesconsisted primarily in having these participants complete a battery of behavioral tests. Therefore,

    each of our eleven replication attempts features the same set of participants. However,

    participants whose behavioral or structural measures deviate more than 2.5 standard deviations

    from the respective mean will be excluded from further analysis.

    Even though our initial focus is on the 36 participants who have completed the behavioral

    test battery, we leave open the possibility of testing additional participants in order to obtain

    clearer results. We are permitted this flexibility in data collection, because we use a Bayesian

    hypothesis test to quantify the evidence for and against the null hypotheses. When using the so-

    called Bayes factor, researchers are allowed to monitor the evidence as the data come in, and

    continue testing until a point has been proven or disproven, or until the experimenter runs out of

    time, money, or patience (Edwards et al., 1963).

    General procedure. Prior to the test session participants receive an information brochure

    with a brief description of all tasks and questionnaires. At the beginning of the test session

    participants sign an informed consent form. Participants are tested in individual computer

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    booths. All instructions are shown on the computer screen or printed on top of the

    questionnaires. Participants begin with filling out the following questionnaires: Behavioral

    Inhibition System/Behavioral Activation System Scales, Social Network Index, Social Network

    Size Questionnaire, Cognitive Failures Questionnaire, and Political Orientation

    Questionnaire. The order in which participants fill out the questionnaires is randomized.

    Note that all questionnaires have been translated into Dutch and can be found in Appendix

    A.After completing the questionnaires, participants continue with the computerized tasks:

    Random dot motion task, bistable structure-from-motion task, and attention network test

    (please find a detailed description of each task below). Again, the order of these tasks is

    randomized per participant. The total duration of the test session is at most 1 hour and 30

    minutes.

    MRI data acquisition. In the earlier MRI experiment, DTI and T1 images have been obtained

    on a 3T Philips scanner using a 32-channel head coil. For each subject, a T1 anatomical scan

    was acquired (T1 turbo field echo, 220 transverse slices of 1 mm, with a resolution of 1mm3,

    TR = 8.2 ms, TE = 3.7 ms). In addition, four repetitions of a multi-slice spin echo (MS-SE),

    single shot diffusion weighted imaging (DWI) scans were obtained using the following

    parameters: TR = 7545 ms, TE = 86 ms, 60 transverse slices, 2 mm slice thickness, FOV: 224 x

    224 mm2, voxel size 2 mm isotropic resolution. For each slice, one image without diffusion

    weighting (b = 0) and 32 diffusion-weighted images (b=1000s/mm 2) along 32 directions

    were acquired.

    MRI data preprocessing and analysis. We will carry out all MRI data analyses in FMRIBs

    Software Library (FSL 4.0; www.fmrib.ox.ac.uk/fsl) and FreeSurfer

    (http://surfer.nmr.mgh.harvard.edu) software.

    VBM preprocessing. Voxel-Based Morphometry will be performed using FSL's

    default VBM pipeline (http://www.fmrib.ox.ac.uk/fsl/fslvbm/index.html). First, non-brain

    tissue will be removed from T1 images using FMRIB's Brain Extraction Tool (BET). Second,

    brain-extracted images will be segmented into gray matter (GM), white matter (WM), and

    cerebrospinal fluid (CSF). GM images will be non-linearly registered to GM ICBM-152, and

    averaged to create a study-specific template at 2mm resolution in standard space. All GM

    images will then be non-linearly registered to the study-specific template. During this stage,

    each voxel of each registered grey matter image is divided by the Jacobian of the warp field

    http://www.fmrib.ox.ac.uk/fslhttp://surfer.nmr.mgh.harvard.edu/http://www.fmrib.ox.ac.uk/fsl/fslvbm/index.htmlhttp://www.fmrib.ox.ac.uk/fsl/fslvbm/index.htmlhttp://surfer.nmr.mgh.harvard.edu/http://www.fmrib.ox.ac.uk/fsl
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    (Good et al., 2001). Finally, images will be smoothed using a Gaussian kernel with a sigma of

    3 mm.

    DTI preprocessing. All four runs of DTI will be merged and corrected for eddy

    currents. Affine registration will be used to register each volume to a reference volume. A

    single image without diffusion weighting (b=0) will be extracted from the merged data and

    non-brain tissue will be removed using BET to create a brain-mask which will be used in

    subsequent analyses. DTIFIT will be then be applied to fit a tensor model at each voxel of

    the data. Finally, tract based spatial statistics (TBSS) will be run. To compute probabilistic

    tractography, Bayesian estimation of diffusion parameters using sampling techniques

    (BedpostX) will be applied. BedpostX uses a dual fiber model which can account for crossing

    fibers.

    TBSS.Tract-Based Spatial Statistics will be performed using FSL's default TBSS

    pipeline (http://www.fmrib.ox.ac.uk/fsl/tbss/index.html). First, FA images are slightly

    eroded and end slices are zeroed, in order to remove likely outliers from the diffusion

    tensor fitting. Second, all FA images will be aligned to 1 mm standard space using non-linear

    registration to the FMRIB58_FA standard-space image. Affine registration is then used to

    align images into 1 x 1 x 1 mm MNI152 space, and a skeletonization procedure is

    subsequently applied to a mean FA image resulting from averaging all individual MNI-

    aligned images. Subsequently, the mean skeletonized FA image is thresholded at > 0.2 in

    order to accurately represent white-matter tracts. Subject's FA data are then projected onto

    the mean skeletonized FA image and concatenated. Finally, the non-linear warps and

    skeletonization procedures resulting from aforementioned FA-TBSS will be used in order to

    construct skeletonized images of other measures (i.e., parallel eigenvalue (1) and mean

    diffusivity (MD)).

    Probabilistic tractography. First, affine registration will be used to align relevant

    MNI masks to subjects individual high-resolution T1 images, and subsequently to subjects

    DTI images. Probabilistic tractography will then be performed using 5.000 tract-following

    samples at each voxel with a curvature threshold of 0.2. Single masks will be used as seed

    space, and we will use classification masks in order to estimate the number of samples

    reaching the relevant target mask. In addition, contralateral exclusion masks will be used to

    discard pathways crossing over to the contralateral seed mask before travelling to the

    classification mask. For the estimation of tract strength, resulting images will be thresholded

    http://www.fmrib.ox.ac.uk/fsl/tbss/index.htmlhttp://www.fmrib.ox.ac.uk/fsl/tbss/index.html
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    at 10 samples and binarized, such that the size of a resulting image will be the amount of

    voxels reliably (that is, in at least 10 samples) reaching the classification mask. This size is

    then divided by the total size of the seed mask, such that the result is a proportion of the

    seed mask, reliably connected to the classification mask. The same is then done for the

    opposite analysis (i.e. when the seed mask and classification mask are switched), and the

    average of the proportions is computed. These steps are necessary to correct for the sizes of

    the masks.

    Bayesian hypothesis test for (partial) correlations. The Bayes factorcompares the

    probability of the observed data under H1 versus H0,and hence quantifies the evidence that

    the data provide for and against the models underconsideration. In what follows, H0 is the

    null model in which correlation is absent, and H1is the alternative model in which

    correlation is present. We distinguish between an H1 thatdoes not commit to a direction for

    the correlation (i.e., a two-sided test), and an H1 thatdoes commit to such a direction (i.e., a

    one-sided test). The latter test is recommendedfor replication projects, or anytime

    researchers have strong prior expectations about thedirection of the association.

    The two-sided test. Under H1, Jeffreys assigned the correlation coefficient a

    uniform prior distribution from -1 to 1 (Jeffreys, 1961). Further, he assumed that the means

    of the observed variablesxand yare 0.

    Then,

    BF10 =

    (1)

    where n is the number of (x, y) pairs and ris the classic Pearson correlation coefficient.

    Note that when the means forxand yneed to be estimated from the data, as is usually the

    case, n in the above equation needs to be replaced by n - 1.

    The above Bayes factor contains a uni-dimensional integral that can be computed

    numerically in R:

    # Jeffreys' earthquake data:

    S

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    integrand

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    Wagenmakers, Lodewyckx, Kuriyal, and Grasman (2010) and Hoijtink, Klugkist, and Boelen

    (2008).

    We will only use the one-sided test, because we aim to replicate the specific

    correlations reported in the studies-to-replicate.

    Study-specific Methods and Analyses

    Replication 1. Individuals with high BAS-Total scores (i.e., sensitivity to signals of reward

    and non-punishment) show increased parallel eigenvalues within left corona radiata (CR)

    and left superior longitudinal fasciculus (SLF). Individuals with high BAS-Fun scores (i.e.,

    tendency to seek out new potentially-rewarding experiences) show increased paralleleigenvalues and fractional anisotropy within left CR and left SLF. These individuals also

    show increased mean diffusivity within left inferior longitudinal fasciculus and left inferior

    fronto-occipital fasciculus.

    Xu, J. Kober, H., Caroll, K. M., Rounsaville, B. J., Pearlson, G. D., & Potenza, M. N. (2012).

    White matter integrity and behavioral activation in healthy subjects. Human Brain Mapping,

    33, 994-1002.

    BIS/BAS questionnaire and procedure. Participants fill out a Dutch version of the Behavioral

    Inhibition System/Behavioral Activation System (BIS/BAS; Carver et al., 1994; see Appendix

    A) scale. The BIS/BAS is a 20-item questionnaire. Our interest will be focused on the BAS

    scale which comprises 13 items (BAS-Total) and has three subscales, Drive (BAS-Drive), Fun-

    Seeking (BAS-Fun), and Reward-Responsiveness (BAS-Reward). Administration time is

    approximately 5 minutes.

    Behavioral analysis. The behavioral measures of interest are BAS-Total scores and BAS-Funscores. BAS-Total scores assess the sensitivity to signals of reward and non-punishment.

    BAS-Fun scores assess the tendency to seek out new potentially-rewarding experiences. For

    each participant these scores will be imported into R (R Foundation for Statistical

    Computing, http://www.R-project.org) for the Bayesian correlation test.

    TOI generation. Xu and colleagues (2012) reported significant positive correlations between

    the BAS-Total scores and parallel eigenvalue (1) within left corona radiata (CR) and left

    superior longitudinal fasciculus (SLF). Furthermore, they reported significant positive

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    correlations between the BAS-Fun scores and 1 as well as fractional anisotropy (FA) within

    left CR and left SLF. The authors also reported significant positive correlations between the

    BAS-Fun scores and mean diffusivity (MD) within left inferior longitudinal fasciculus (ILF) and

    left inferior fronto-occipital fasciculus (IFOF). We defined all these white matter (WM) tracts

    as our tracts of interest (TOIs). Dr. Xu kindly provided us with the masks/templates that

    were used in the original study. We will use these for the segmentation of our confirmatory

    TOIs.

    Correlational analysis. Before performing the Bayesian hypothesis test for correlations (as

    described above), we will extract FA, MD, and 1 values from all voxels contained in the

    respective TOIs and average them. This will be done for every subject. These WM tract

    measures are then corrected for age and gender using partial correlations. Unlike Xu and

    colleagues we will not correct for education. Our participants are all Psychology freshmen,

    therefore we can rule out substantial differences in education. The corrected mean WM

    tract measures per TOI will be imported into R (R Foundation for Statistical Computing,

    http://www.R-project.org) software for the Bayesian correlation test. Specifically, we will

    test for positive correlations between BAS-Total scores and mean 1 within left CR and left

    SLF. Furthermore, we will test for positive correlations between BAS-Fun scores and mean 1

    as well as mean FA within left CR and left SLF. Finally, we will test for positive correlations

    between BAS-Fun scores and mean MD within left ILF and left IFOF.

    Replication 2. Individuals with high LBA flexibility (i.e., good control over speed and

    accuracy in perceptual decision making) show increased tract strength of white matter

    fibers connecting right pre-SMA and right striatum.

    Forstmann, B. U., Anwander, A., Schfer, A., Neumann, J., Brown, S., Wagenmakers, E.-J.,

    Bogacz, R., et al. (2010). Cortico-striatal connections predict control over speed and accuracy

    in perceptual decision making. Proceedings of the National Academy of Sciences of the

    United States of America, 107(36), 15916-15920.

    Random dot motion task and procedure.We use the same random dot motion (RDM) task

    (Gold & Shadlen, 2001) as Forstmann and colleagues (2010; see Figure 1).

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    The experiment features 360 trials in total, with 180 speed and 180 accuracy trials. A cloud

    consisting of 120 white dots with 50% coherently moving dots and 50% randomly moving

    dots is presented against a black background. A single dot consists of 3 pixels and the whole

    cloud has a diameter of 250 (uniformly distributed) pixels. At the beginning of each trial

    either a speed- or an accuracy-cue is presented for 1000 ms. The speed-accuracy tradeoff(SAT) in this task is manipulated by pseudo-randomized presentation of the two different

    cue-types. The speed cue instructs participants to adopt a liberal level of cautiousness,

    responding as quickly as possible. The accuracy cue, however, instructs participants to adopt

    a more conservative level of cautiousness, responding as accurate as possible. After the cue,

    a fixation cross is presented at the center of the screen for 500 ms. Subsequently, the RDM

    stimulus is shown until a response is made, but at most for 1500 ms. Responses have to be

    made within this time window. Participants respond by pressing a with their left index

    finger when they perceive a leftward motion and l with their right index finger when they

    perceive a rightward motion. Immediately after the response participants receive feedback

    (400 ms) that is dependent on the trial-type. They see either te traag (Dutch for too

    slow)/fout (Dutch for incorrect) or op tijd (Dutch for in time)/goed (Dutch for

    correct). After 120 and 240 trials participants can choose to take a break of up to 45

    seconds. The entire experiment takes approximately 20 minutes.

    Figure 1. Random Dot Motion paradigm with cues

    emphasizing speed (SN Dutch abbreviation for fast)and accuracy (AC Dutch abbreviation for accurate).

    Note. Figure taken from Forstmann et al. 2010 and edited.

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    LBA model. The linear ballistic accumulator (LBA; Brown et al., 2008) model serves to

    decompose the response time and accuracy measures into latent psychological processes.

    The decision process of interest, here, is response caution, which can be quantified by

    means of the LBA. We will apply the same parameter constraints as Forstmann and

    colleagues (2010). In this design only one parameter - response threshold (b) - will be free to

    vary with the speed vs. accuracy cue, while all other parameters (start point distribution (A),

    drift rate for the response (v), variability of the drift rate (s) and nondecision time (t0)) will

    be fixed.

    Behavioral data analysis. The behavioral measure of interest is the LBA flexibility

    parameter, assessing efficacy of changing response caution. It is assumed that changes in

    response caution originate from adjustments of response thresholds (Forstmann et al.,

    2010; pp. 1516). Therefore, LBA flexibility is computed as the difference between the LBA

    threshold estimates for the accuracy (baccuracy) and the speed (bspeed) conditions. We will fit

    the LBA model to each participant's RT and accuracy measures on speed and accuracy trials

    separately. The only parameter allowed to vary will be the response threshold b. The

    resulting individual LBA flexibility estimates will be imported into R for the Bayesian

    correlation test.

    TOI analysis. Forstmann and colleagues (2010) reported a significant positive correlation

    between LBA flexibility and tract strength of white matter (WM) fibers connecting right pre-

    SMA and right striatum. We defined this WM fiber tract as our tract-of-interest (TOI). We

    will use the mask/template that was used in the original study for the segmentation of our

    confirmatory TOI.

    Probabilistic tractography. We will limit our tractography to delineate tracts that the

    authors found to significantly correlate with LBA flexibility. Hence, probabilistic tractography

    will be performed only on fibers connecting right pre-SMA and right striatum. We will

    perform the probabilistic tractography conform the protocol stated in the general methods

    and analyses section (see above).

    Correlational analysis. Before performing the Bayesian hypothesis test for correlations (as

    described above), we will extract tract strength values from all voxels contained in the

    relevant TOI and average them. This will be done for every subject. These tract strength

    measures are then corrected for age and gender using partial correlations. The corrected

    mean tract strength measures will be imported into R (R Foundation for Statistical

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    Computing, http://www.R-project.org) software for the Bayesian correlation test.

    Specifically, we will test for a positive correlation between LBA flexibility and WM tract

    strength of fibers connecting right pre-SMA and right striatum.

    Replication 3. Individuals with short percept durations in perceptual rivalry show

    increased cortical thickness within superior parietal lobe (SPL) and postcentral gyrus,

    increased gray matter volume within SPL, and increased fractional anisotropy of white

    matter fibers underneath SPL.

    Kanai, R., Bahrami, B., & Rees, G. (2010). Human parietal cortex structure predicts individual

    differences in perceptual rivalry. Current Biology, 20(18), 1626-1630.

    Bistable SFM task. We use the same ambiguous rotating structure-from-motion (SFM)

    stimulus task as Kanai and colleagues (2010; see Figure 2).

    Figure 2. Bistable Structure-From-Motion Stimulus.

    Note. Figure taken from Kanai et al. 2010.

    The task includes 8 trials and 1 practice trial. Participants are presented with an ambiguous

    rotating sphere, consisting of 200 full white dots. The dots move sinusoidally at a constant

    speed (151 deg/s). However, the rotation of the sphere can be perceived as either rightward

    or leftward. A red fixation dot is presented at the center of the screen and participants are

    instructed to steadily fixate. The trial duration is 48 seconds. Participants report the

    duration of their percept of the rotation direction (right or left) of the SFM stimulus by

    holding the spatially compatible key (left arrow or right arrow on a regular keyboard) with

    their left or right index finger until the percept switches to the other direction. The entire

    experiment takes approximately 10 minutes.

    Behavioral data analysis. The behavioral measure of interest is percept duration, assessing

    bistable perception. Besides computing the mean percept duration, we will also compute its

    reciprocal, the switch rate, for each participant and import these values into R (R

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    Foundation for Statistical Computing, http://www.R-project.org) software for the Bayesian

    correlation test.

    ROI generation. Kanai and colleagues (2010) reported significant negative correlations

    between percept duration and cortical thickness (CT) within bilateral superior parietal lobe

    (SPL) and bilateral postcentral gyrus. For gray matter (GM) volume they reported significant

    negative correlations with percept duration within right and left SPL. White matter

    fractional anisotropy (FA) showed a significant negative correlation with percept duration

    underneath right and left SPL. We defined all these regions as our regions of interest (ROIs).

    Dr. Kanai kindly provided us with the masks/templates that were used in the original study.

    We will use these for the segmentation of our confirmatory ROIs.

    Correlational analysis. Before performing the Bayesian hypothesis test for correlations (as

    described above), we will extract CT, GM, and FA values from all voxels contained in the

    respective ROIs and average them. This will be done for every subject. These structural brain

    measures are then corrected for age and gender using partial correlations. The corrected

    mean CT, GM, and FA measures per ROI will be imported into R (R Foundation for Statistical

    Computing, http://www.R-project.org) software for the Bayesian correlation test.

    Specifically, we will test for negative correlations between percept duration and mean CT

    within bilateral SPL and bilateral postcentral gyrus. We will also test for negative

    correlations between percept duration and mean GM volume within right and left SPL.

    Finally, we will test for negative correlations between percept duration and mean FA

    underneath right and left SPL.

    Replication 4. Individuals with long percept durations in perceptual rivalry show increased

    gray matter volume within right anterior superior parietal lobe.

    Kanai, R., Carmel, D., Bahrami, B., & Rees, G. (2011a). Structural and functional fractionation

    of right superior parietal cortex in bistable perception. Current Biology, 21(3), R106-R107.

    Bistable SFM task. We use the same ambiguous rotating structure-from-motion (SFM)

    stimulus task as Kanai and colleagues (2011a; see Figure 2). For a detailed description of the

    task please refer back to Replication 3.

    Behavioral data analysis. The behavioral measure of interest is percept duration (and

    switch rate), assessing bistable perception. We will compute the mean percept duration for

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    each participant and import these values into R (R Foundation for Statistical Computing,

    http://www.R-project.org) software for the Bayesian correlation test.

    ROI generation. Kanai and colleagues (2011a) reported a significant positive correlation

    between percept duration and gray matter (GM) volume within right anterior superior

    parietal lobe (aSPL). We defined this region as our region of interest (ROI). Dr. Kanai kindly

    provided us with the mask/template that was used in the original study. We will use this

    mask/template for the segmentation of our confirmatory ROI.

    Correlational analysis. Before performing the Bayesian hypothesis test for correlations (as

    described above), we will extract GM values from all voxels contained in the ROI and

    average them. This will be done for every subject. These GM measures are then corrected

    for age and gender using partial correlations. The corrected mean GM measures will be

    imported into R (R Foundation for Statistical Computing, http://www.R-project.org)

    software for the Bayesian correlation test. Specifically, we will test for a positive correlation

    between percept duration and mean GM volume within right aSPL.

    Replication 5. Individuals with a small difference in reaction times between trials with

    incongruent and congruent stimuli (i.e., good executive control) show increased cortical

    thickness within left caudal anterior cingulate cortex, left superior temporal lobe, and

    right middle temporal lobe. Individuals with a small difference in reaction times between

    trials with no cue and a central cue (i.e., good alerting ability) show increased cortical

    thickness within medial and lateral aspects of the left superior temporal lobe.

    Westlye, L. T., Grydeland, H., Walhovd, K. B., & Fjell, A. M. (2011). Associations between

    regional cortical thickness and attentional networks as measured by the attention network

    test. Cerebral Cortex, 21(2), 345-356.

    Attention Network Test. We use the same Attention Network Test (ANT) as Westlye and

    colleagues (2011; downloaded from Dr. Jin Fans website

    www.sacklerinstitute.org/users/jin.fan; see Figure 3). The task includes 2 runs of 96 trials

    and 20 practice trials. Each trial begins with the presentation of a fixation cross in the center

    of the screen for variable durations (400, 800, 1200, or 1600 ms). Subsequently, one of

    three cues is presented for 100 ms: (1) no cue, (2) center cue (*, replacing fixation cross), or

    (3) spatial cue (*, above or below fixation cross). Then the target is presented for a

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    maximum duration of 1700 ms (until a response is made). The target is an arrow in the

    center of a row of 5 arrows, presented below or above the fixation cross. The flanking

    arrows can be (1) two congruent arrows (pointing in the same direction as the target), (2)

    two incongruent arrows (pointing in the opposite direction of the target), or (3) two lines on

    each side of the target (neutral). Participants are instructed to report the direction (left or

    right) of the target arrow by pressing the spatially compatible key (left mouse button and

    right mouse button) with their left or right thumb. The entire experiment takes

    approximately 15 minutes.

    Figure 3. Attentional Network Test Paradigm.

    Behavioral data analysis. The behavioral measures of interest are executive control (EC)

    and alerting network scores, assessing the executive control and the alerting components of

    attention, respectively. We will apply the same processing steps as described by Westlye

    and colleagues (2011) before we compute the two network scores:

    To remove outliers, all RTs > 1500 ms and < 200 ms were removed (). Next, since error responses

    are assumed to originate from a different RT distribution than correct responses, we only analyzed

    correct responses. Also, because responses following erroneous responses typically are slower than

    responses following correct responses (posterror slowing), we also removed responses following

    erroneous responses. Since RTs are not normally distributed, we used median RT per condition as

    raw scores for each subject (pp. 348).

    However, we will not adjust the component scores with the baseline RT in order to control

    for an effect of age on RT, because our participants form a homogenous age group

    (Psychology freshmen).

    Based on median RT the EC score will be computed as follows:

    EC = [RTincongruent - RTcongruent] / RTcongruent

    Based on median RT the alerting score will be computed as follows:

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    Alerting = [RTno cue RTcenter cue] / RTcenter cue

    For each participant the resulting scores will be imported into R (R Foundation for Statistical

    Computing, http://www.R-project.org) software for the Bayesian correlation test.

    ROI generation. For their subsample of young participants, Westlye and colleagues (2011)

    reported significant negative correlations between EC scores and cortical thickness (CT)

    within left caudal anterior cingulate cortex (ACC), left superior temporal lobe (STL), and right

    middle temporal lobe (MTL). The A scores showed a significant negative correlation with CT

    within left superior parietal lobe (SPL). We defined all these regions as our regions of

    interest (ROIs). Dr. Westlye kindly provided us with the masks/templates (i.e., labels used in

    FreeSurfer (http://surfer.nmr.mgh.harvard.edu) software) that were used in the original

    study. We will use these for the segmentation of our confirmatory ROIs.

    Correlational analysis. Before performing the Bayesian hypothesis test for correlations (as

    described above), we will extract CT values from all voxels contained in the ROIs and

    average them. This will be done for every subject. These CT measures are then corrected for

    age and gender using partial correlations. The corrected mean CT measures will be imported

    into R (R Foundation for Statistical Computing, http://www.R-project.org) software for the

    Bayesian correlation test. Specifically, we will test for negative correlations between EC

    scores and mean CT within left caudal ACC, left STL and right MTL. Furthermore, we will test

    for a negative correlation between alerting scores and mean CT within left SPL.

    Replication 6. Young individuals with high scores on the Social Network Index (i.e., large

    social networks) show increased gray matter volume within bilateral amygdala and

    increased cortical thickness within right subgenual anterior cingulate cortex, left caudal

    superior frontal gyrus and left caudal inferior temporal sulcus.

    Bickart, K. C., Wright, C. I., Dautoff, R. J., Dickerson, B. C., & Barrett, L. F. (2011). Amygdala

    volume and social network size in humans. Nature Neuroscience, 14(2), 163-164.

    Social Network Index questionnaire and procedure. Participants fill out a Dutch version of

    the Social Network Index (SNI) questionnaire. The questionnaire has 12 items, measuring

    aspects of social cognition: Social network diversity (SND), social network size (SNS) and

    social network complexity (SNC). Administration time is approximately 10 minutes.

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    Behavioral data analysis. The behavioral measures of interest are SNS (i.e., the total

    number of people with whom the respondent has regular contact) and SNC (i.e., the

    number of different groups that these contacts belong to). Thus, for each participant the

    resulting SNS and SNC scores will be imported into R (R Foundation for Statistical

    Computing, http://www.R-project.org) software for the Bayesian correlation test.

    ROI generation. For their subsample of young participants, Bickart and colleagues (2011)

    reported significant positive correlations between SNS/SNC (similar results) and gray matter

    (GM) volume within left and right amygdala. Furthermore, they reported significant positive

    correlations between SNS/SNC (similar results) and cortical thickness (CT) within right

    subgenual anterior cingulate cortex (sgACC), left caudal superior frontal gyrus (cSFG), and

    left caudal inferior temporal sulcus (cITS). We defined all these regions as our regions of

    interest (ROIs). Dr. Feldman Barrett, Dr. Dickerson, and Kevin Bickart kindly agreed to

    provide us with the masks/templates that were used in the original study. We will use these

    for the segmentation of our confirmatory ROIs.

    Correlational analysis. Before performing the Bayesian hypothesis test for correlations (as

    described above), we will extract gray matter (GM) and cortical thickness (CT) values from all

    voxels contained in the respective ROIs and average them. This will be done for every

    subject. These GM and CT measures will then be corrected for age and gender using partial

    correlations. The GM measures will additionally be corrected for total intracranial volume.

    The corrected mean GM and CT measures will be imported into R (R Foundation for

    Statistical Computing, http://www.R-project.org) software for the Bayesian correlation test.

    Specifically, we will test for positive correlations between SNS/SNC and mean GM volume

    within left and right amygdala as well as mean CT within right sgACC, left cSFG, and left cITS.

    Replication 7. Individuals with a large number of friends on Facebook (i.e., large online

    social network) show increased gray matter volume within the following regions: left

    middle temporal gyrus, right posterior superior temporal sulcus, right entorhinal cortex,

    and bilateral amygdala. Individuals with high scores on the Social Network Size

    Questionnaire (i.e., large real-world social network) show increased gray matter volume

    within right amygdala.

    Kanai, R., Bahrami, B., Roylance, R., & Rees, G. (2012). Online social network size is reflected

    in human brain structure. Proceedings of the Royal Society Biological sciences, 279(1732),

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    1327-1334.

    Social Network Size Questionnaire and procedure. Participants fill out a Dutch version of

    the Social Network Size questionnaire (Stileman & Bates, 2007; see Appendix A). This

    questionnaire consists of 9 items. One of its items is: How many friends do you have on

    Facebook?. We ask participants to make a note of the number of friends they have on

    Facebook or an alternative comparable social network site such as myspace or the Dutch

    Hyves and bring it to the test session. Administration time is approximately 10 minutes.

    Behavioral data analysis. The behavioral measures of interest are online social network size

    (i.e., the number of Facebook friends (FBN)) and real-world social network size. Subjects

    answers to the 9 subquestions contained in this questionnaire will be square-root

    transformed to correct for skewness. We will compute the FBN as the square root of

    subjects answer to the question: How many friends do you have on Facebook?. A

    normalized real-world social network size score will be computed per participant by

    averaging the z-scores for the questionnaire items 1, 2, 4, 5, 6, 8 and 9 after skewness

    correction. Thus, for each participant an online social network size score and a real-world

    social network size score will be imported into R (R Foundation for Statistical Computing,

    http://www.R-project.org) software for the Bayesian correlation test.

    ROI generation. Kanai and colleagues (2012) reported significant positive correlations

    between online social network size and gray matter (GM) volume within left middle

    temporal gyrus (MTG), right superior temporal sulcus (STS), right entorhinal cortex (EC), and

    bilateral amygdala. Real-world social network size was significantly and positively correlated

    with GM only within right amygdala. We defined all these regions as our regions of interest

    (ROIs). Dr. Kanai kindly provided us with the masks/templates that were used in the original

    study. We will use these for the segmentation of our confirmatory ROIs.

    Correlational analysis. Before performing the Bayesian hypothesis test for correlations (as

    described above), we will extract gray matter (GM) values from all voxels contained in the

    ROIs and average them. This will be done for every subject. These GM measures will then be

    corrected for age, gender and total gray matter volume. The corrected mean GM measures

    will be imported into R (R Foundation for Statistical Computing, http://www.R-project.org)

    software for the Bayesian correlation test. Specifically, we will test for positive correlations

    between FBN and mean GM volume within left MTG, right STS, right EC, and bilateral

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    amygdala. Furthermore, we will test for a positive correlation between real-world network

    size scores and mean GM volume within right amygdala. Since our Bayesian correlation test

    allows us to quantify evidence in favor of a null-effect, we will also test for the absence of

    positive correlations between real-world social network size and mean GM volume within

    left MTG, right STS, right EC, and left amygdala.

    Replication 8. Individuals with high scores on the Cognitive Failure Questionnaire (i.e.,

    high distractibility) show increased gray matter volume within left superior parietal lobule

    and decreased gray matter volume within left mid prefrontal cortex.

    Kanai, R., Dong, M. Y., Bahrami, B., & Rees, G. (2011d). Distractibility in daily life is reflected

    in the structure and function of human parietal cortex.Journal of Neuroscience, 31(18),

    6620-6626.

    Cognitive Failures Questionnaire and procedure.Participants fill out a Dutch version of the

    Cognitive Failures Questionnaire (CFQ, Broadbent et al., 1982; see Appendix A).

    Administration time is approximately 5 minutes.

    Behavioral data analysis. The behavioral measure of interest is distractibility as assessed by

    the CFQ. As in Kanai et al. (2011d), we will quantify distractibility by computing the standard

    loadings derived from a previous factor analysis (Wallace et al., 2002). Specifically, we will

    use the following 9 items: 1, 2, 3, 4, 15, 19, 21, 22, and 25. Scores on these items will be

    imported into R (R Foundation for Statistical Computing, http://www.R-project.org)

    software for the Bayesian correlation test.

    ROI generation. Kanai and colleagues (2011d) reported a significant positive correlation

    between CFQ scores and gray matter (GM) volume within left superior parietal lobe (SPL).

    Furthermore, the authors reported a weak negative correlation between CFQ scores and

    GM volume within left mid prefrontal cortex (mPFC). We defined these regions as our

    regions of interest (ROIs).Dr. Kanai kindly provided us with the masks/templates that were

    used in the original study. We will use these for the segmentation of our confirmatory ROIs.

    Correlational analysis. Before performing the Bayesian hypothesis test for correlations (as

    described above), we will extract gray matter (GM) values from all voxels contained in the

    respective ROIs and average them. This will be done for every subject. These GM measures

    are then corrected for age, gender and total gray matter volume using partial correlations.

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    The corrected mean GM measures will be imported into R (R Foundation for Statistical

    Computing, http://www.R-project.org) software for the Bayesian correlation test.

    Specifically, we will test for a positive correlation between CFQ scores and mean GM

    volumes within left SPL and for a negative correlation within left mPFC.

    Replication 9. Individuals with high scores on the Political Orientation Questionnaire (i.e.,

    conservative) show increased gray matter volume within right amygdala and left insula,

    and decreased gray matter volume within right entorhinal cortex. Individuals with low

    scores on the Political Orientation Questionnaire (i.e., liberal) show increased gray matter

    volume within anterior cingulate cortex.

    Kanai, R., Feilden, T., Firth, C., & Rees, G. (2011c). Political orientations are correlated with

    brain structure in young adults. Current Biology, 21, 677-680.

    Political Orientation Questionnaire and procedure.Participants fill out a Dutch version of

    the Political Orientation Questionnaire (POQ) used by Kanai and colleagues (2011c; see

    Appendix A). The POQ consist of a five-point scale: (1) very liberal, (2) liberal, (3) middel-of-

    the-road, (4) conservative, (5) very conservative. Administration time is approximately 1

    minute.

    Behavioral data analysis. The behavioral measure of interest is political orientation. For

    each participant a political orientation score will be imported into R (R Foundation for

    Statistical Computing, http://www.R-project.org) software for the Bayesian correlation test.

    ROI generation. Kanai and colleagues (2011c) reported significant positive correlations

    between high POQ scores (i.e., conservatism) and gray matter (GM) volume within right

    amygdala and left insula. GM volume was significantly and negatively correlated with

    conservatism within right entorhinal cortex (EC). Furthermore, the authors reported a

    significant negative correlation between low POQ scores (i.e., liberalism) and GM volume

    within anterior cingulate cortex (ACC). We defined all these regions as our regions of

    interest (ROIs). Dr. Kanai kindly provided us with the masks/templates that were used in the

    original study. We will use these for the segmentation of our confirmatory ROIs.

    Correlational analysis. Before performing the Bayesian hypothesis test for correlations (as

    described above), we will extract gray matter (GM) values from all voxels contained in the

    respective ROIs and average them. This will be done for every subject. These GM measures

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    are then corrected for age, gender, and total gray matter volume using partial correlations.

    The corrected mean GM measures will be imported into R (R Foundation for Statistical

    Computing, http://www.R-project.org) software for the Bayesian correlation test.

    Specifically, we will test for positive correlations between conservatism and mean GM

    volume within right amygdala and left insula. We will also test for a negative correlation

    between conservatism and mean GM volume within right entorhinal cortex. Furthermore,

    we will test for a negative correlation between liberalism and mean GM volume within ACC.

    Finally, we will attempt to replicate the absence of a significant positive correlation between

    conservatism and mean GM volume within left amygdala.

    Replication 10. Individuals with high individualizing scores (i.e., values of harm/care and

    fairness; aggregate score on corresponding subscales) show increased gray matter volume

    within left dorsomedial prefrontal cortex (DMPFC) and a marginally significant decrease in

    gray matter volume within bilateral precuneus. Specifically, individuals scoring high on the

    harm subscale show decreased gray matter volume within bilateral precuneus and left

    postcentral gyrus. Individuals scoring high on the fairness subscale show a trend to

    significantly increased gray matter volume within left DMPFC.

    Individuals with high binding scores (i.e. deference to authority, purity/sanctity and in-

    group loyalty; aggregate score on corresponding subscales) show increased gray matter

    volume within bilateral subcallosal gyrus and a marginally significant increase in gray

    matter volume within left anterior insula. Specifically, individuals scoring high on the

    authority subscale show increased gray matter volume within bilateral subcallosal gyrus.

    Likewise, individuals scoring high on the purity subscale show increased gray matter

    volume within bilateral subcallosal gyrus. Furthermore, they show increased gray matter

    volume within left anterior insula and a trend to increased gray matter volume within

    right anterior insula. This trend is significant for individuals scoring high on disgust (based

    on a subset of the purity items dealing with disgust).

    Lewis, G., Kanai, R., Bates, T. & Rees, G. (2012). Moral values are associated with individual

    differences in regional brain volume.Journal of Cognitive Neuroscience, 24(8), 1657-1663.

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    Moral Foundations Questionnaire and procedure.Participants fill out a Dutch version of the

    Moral Foundations Questionnaire (MFQ; Graham et al., 2009; see Appendix A). The MFQ

    measures five foundations of moral behavior:

    (1) harm (minimizing harm to others), (2) fairness (maximizing fairness to all), (3) in-group loyalty

    (the importance of the in-group), (4) authority (respect for status and hierarchy), and (5) purity

    (avoiding impure or disgusting acts/entities) (Lewis et al., 2012; pp. 1657).

    Administration time is approximately 10 minutes.

    Behavioral data analysis. The behavioral measures of interest are individualizing and

    binding, assessing moral values.For each participant an individualizing (aggregate score on

    harm and fairness components) and a binding score (aggregate score on authority, in-group

    loyalty and purity) will be imported into R for the Bayesian correlation test.

    ROI generation. Lewis and colleagues (2012) reported a significant positive correlation

    between individualizing scores and gray matter (GM) volume within left dorsomedial

    prefrontal cortex (DMPFC) and a marginally significant negative correlation between these

    measures within bilateral precuneus. The authors also reported significant negative

    correlations between harm subscores and GM volume within bilateral precuneus and left

    postcentral gyrus. A marginally significant positive correlation was reported between

    fairness subscores and GM volume within left DMPFC. Furthermore, the authors reported a

    significant positive correlation between binding scores and GM volume within bilateral

    subcallosal gyrus, and a marginally significant positive correlation between these measures

    within left anterior insula. For authority as well as purity subscores the authors reported a

    significant positive correlation with GM volume within bilateral subcallosal gyrus. In

    addition, a significant positive correlation and a trend to a significant positive correlation

    were found between purity subscores and GM volume within left anterior insula and right

    anterior insula, respectively. Finally, the authors reported a significant positive correlation

    between disgust subscores (based on a subset of purity items dealing with disgust) and GM

    volume within right anterior insula. We defined all these regions as our regions of interest

    (ROIs). Dr. Kanai kindly agreed to provide us with the masks/templates that were used in the

    original study. We will use these for the segmentation of our confirmatory ROIs.

    Correlational analysis. Before performing the Bayesian hypothesis test for correlations (as

    described above), we will extract gray matter (GM) values from all voxels contained in the

    respective ROIs and average them. This will be done for every subject. These GM measures

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    are then corrected for age, gender, and total gray matter volume using partial correlations.

    The corrected mean GM measures will be imported into R (R Foundation for Statistical

    Computing, http://www.R-project.org) software for the Bayesian correlation test.

    Specifically, we will test for a positive correlation between individualizing scores and mean

    GM volume within left DMPFC, and a negative correlation between these measures within

    bilateral precuneus. Furthermore, we will test for negative correlations between harm

    subscores and mean GM volume within bilateral precuneus and left postcentral gyrus. We

    will also test for a positive correlation between fairness subscores and mean GM volume

    within left DMPFC. Subsequently, we will test for positive correlations between binding

    scores and mean GM within bilateral subcallosal gyrus and left anterior insula. Authority and

    purity subscores will be tested for a positive correlation with mean GM volume within

    bilateral subcallosal gyrus. In addition, purity subscores will be tested for positive

    correlations with mean GM volume within left and right anterior insula. Finally, we will test

    for a positive correlation between disgust scores (based on a subset of purity items dealing

    with disgust) and mean GM volume within right anterior insula.

    Replication 11. Individuals with high empathic concern scores show decreased gray matter

    volume within the following regions: left precuneus, left anterior cingulate, and anterior

    insula. Individuals with high personal distress scores show increased gray matter volume

    within left anterior insula and decreased gray matter volume within left somatosensory

    cortex. Individuals with high perspective taking scores show increased gray matter volume

    within left anterior cingulate. Individuals with high fantasy scores show increased gray

    matter volume within right dorsolateral prefrontal cortex.

    Banissy, M. J., Kanai, R., Walsh, V., & Rees, G. (2012). Inter-individual differences in empathy

    are reflected in human brain structure. NeuroImage, 62(3), 2034-2039.

    Interpersonal Reactivity Index and procedure.Participants fill out a Dutch version of the

    Interpersonal Reactivity Index (IRI; Davis, 1980; translated and validated by De Corte et al.,

    2007; see Appendix A). The IRI has 28 items and comprises four subscales:

    () perspective taking; personal distress; empathic concern; and fantasy (Davis, 1980; Davis, Luce,

    and Kraus, 1994). Empathic concern and personal distress measure affective reactions but differ in

    their targets. Personal distress is self-oriented and associated to aversive emotional responses in the

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    observer (e.g. feelings of fear or discomfort at witnessing negative experiences of others). Empathic

    concern is other-oriented and related to feelings of compassion and sympathy for the observed

    individual. Perspective taking examines the tendency to think from another perspective (i.e.

    cognitive responses). Fantasy examines participants abilities to transpose themselves into fictional

    situations (e.g. books, movies, daydreams).

    Each subscale contained seven items. They were measured on a five point Likert scale

    ranging from 0 (Does not describe me well) to 4 (Describes me very well). For each subscale, a

    minimum score of 0 or maximum score of 28 was possible (Banissy et al., 2012; pp. 2035).

    Administration time is approximately 10 minutes.

    Behavioral data analysis. The behavioral measures of interest are empathic concern (EC),

    personal distress (PD), perspective taking (PT), and fantasy (FS), assessing different aspects

    of empathy.For each participant we will import one score for each measure into R (R

    Foundation for Statistical Computing, http://www.R-project.org) for the Bayesian

    correlation test.

    ROI generation. Banissy and colleagues (2012) reported significant negative correlations

    between EC and gray matter (GM) volume within left precuneus, left anterior cingulate, and

    left anterior insula. Furthermore, the authors reported a significant negative correlation

    between PD and GM volume within left somatosensory cortex and a positive correlationbetween these measures within left anterior insula. PT was positively correlated with GM

    volume within left anterior cingulate and FS was positively correlated with GM volume

    within right dorsolateral prefrontal cortex. We defined all these regions as our regions of

    interest (ROIs). Dr. Kanai kindly agreed to provide us with the masks/templates that were

    used in the original study. We will use these for the segmentation of our confirmatory ROIs.

    Correlational analysis. Before performing the Bayesian hypothesis test for correlations (as

    described above), we will extract gray matter (GM) values from all voxels contained in the

    respective ROIs and average them. This will be done for every subject. These GM measures

    are then corrected for age, gender, and total gray matter volume using partial correlations.

    The corrected mean GM measures will be imported into R (R Foundation for Statistical

    Computing, http://www.R-project.org) software for the Bayesian correlation test.

    Specifically, we will test for negative correlations between empathic concern scores and

    mean GM volume within left precuneus, left anterior cingulate and left anterior insula.

    Furthermore, we will test for a negative correlation between personal distress scores and

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    mean GM volume within somatosensory cortex, and a positive correlation between these

    measures within left anterior insula. We will also test for a positive correlation between

    perspective taking scores and mean GM volume within left anterior cingulate. Finally, we

    will test for a positive correlation between fantasy scores and mean GM volume within right

    dorsolateral prefrontal cortex.

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    Appendix A:Translated questionnaires used in the present replication study.

    1. Dutch Translation of Behavioral Inhibition System/Behavioral Activation System

    (adapted from Carver et al., 1994)

    Op de volgende bladzijden vindt je een aantal beweringen. De bedoeling is dat je deze

    beweringen doorleest en dat je nagaat of zij van toepassing zijn.

    Naast elke bewering staan vier antwoordmogelijkheden die variren van "helemaal mee

    eens" tot "helemaal mee oneens". Het is de bedoeling dat je telkens met een kruisje in n

    van de hokjes aangeeft in hoeverre een bewering op jou van toepassing is.

    Laat geen vraag onbeantwoord en beperk je tot de gegeven antwoordmogelijkheden.

    Neem je tijd, maar denk niet al te lang na over een vraag.

    1. Als ik denk dat er iets onprettigs gaat gebeuren, raak ik meestal behoorlijk "opgefokt".

    0 helemaal mee eens

    0 beetje mee eens

    0 beetje mee oneens

    0 helemaal mee oneens

    2. Ik ben bezorgd om het maken van fouten.

    0 helemaal mee eens

    0 beetje mee eens

    0 beetje mee oneens

    0 helemaal mee oneens

    3. Als ik iets wil, ga ik er meestal helemaal voor.

    0 helemaal mee eens

    0 beetje mee eens

    0 beetje mee oneens

    0 helemaal mee oneens

    4. Vaak doe ik dingen om geen andere reden dan dat het wel eens leuk zou kunnen zijn.

    0 helemaal mee eens

    0 beetje mee eens

    0 beetje mee oneens0 helemaal mee oneens

    5. Kritiek of een standje raken mij behoorlijk.

    0 helemaal mee eens

    0 beetje mee eens

    0 beetje mee oneens

    0 helemaal mee oneens

    6. Als ik iets krijg wat ik wil, voel ik me opgewonden en opgeladen.

    0 helemaal mee eens0 beetje mee eens

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    0 beetje mee oneens

    0 helemaal mee oneens

    7. Ik doe een hoop moeite om dingen die ik wil te krijgen.

    0 helemaal mee eens

    0 beetje mee eens

    0 beetje mee oneens

    0 helemaal mee oneens

    8. Ik verlang sterk naar spanning en nieuwe sensaties.

    0 helemaal mee eens

    0 beetje mee eens

    0 beetje mee oneens

    0 helemaal mee oneens

    9. Ik voel me behoorlijk overstuur als ik denk of weet dat iemand boos op me is.0 helemaal mee eens

    0 beetje mee eens

    0 beetje mee oneens

    0 helemaal mee oneens

    10. Ik ben altijd bereid iets nieuws te proberen als ik denk dat het leuk zal zijn.

    0 helemaal mee eens

    0 beetje mee eens

    0 beetje mee oneens

    0 helemaal mee oneens

    11. Als ik iets goed doe, wil ik er graag mee doorgaan.

    0 helemaal mee eens

    0 beetje mee eens

    0 beetje mee oneens

    0 helemaal mee oneens

    12. Zelfs als mij iets ergs staat te gebeuren, ervaar ik zelden angst of nervositeit.

    0 helemaal mee eens

    0 beetje mee eens0 beetje mee oneens

    0 helemaal mee oneens

    13. Ik handel vaak zoals het moment me ingeeft.

    0 helemaal mee eens

    0 beetje mee eens

    0 beetje mee oneens

    0 helemaal mee oneens

    14. Als ik een kans zie iets te krijgen wat ik wil, ga ik er meteen op af.0 helemaal mee eens

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    0 beetje mee eens

    0 beetje mee oneens

    0 helemaal mee oneens

    15. Als mij goede dingen overkomen, raakt dat me sterk.

    0 helemaal mee eens

    0 beetje mee eens

    0 beetje mee oneens

    0 helemaal mee oneens

    16. Ik voel me bezorgd als ik denk dat ik slecht heb gepresteerd op iets.

    0 helemaal mee eens

    0 beetje mee eens

    0 beetje mee oneens

    0 helemaal mee oneens

    17. Ik zou het spannend vinden een wedstrijd te winnen.

    0 helemaal mee eens

    0 beetje mee eens

    0 beetje mee oneens

    0 helemaal mee oneens

    18. Vergeleken met mijn vrienden heb ik erg weinig angsten.

    0 helemaal mee eens

    0 beetje mee eens

    0 beetje mee oneens0 helemaal mee oneens

    19. Als ik een mogelijkheid zie iets te krijgen wat ik leuk vind, word ik direct opgewonden.

    0 helemaal mee eens

    0 beetje mee eens

    0 beetje mee oneens

    0 helemaal mee oneens

    20. Als ik ergens werk van maak, gooi ik ook mijn volle gewicht er tegenaan.

    0 helemaal mee eens0 beetje mee eens

    0 beetje mee oneens

    0 helemaal mee oneens

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    2. Dutch Translation of Social Network Index

    (adapted from Cohen et al., 1997)

    Instructies: Deze vragenlijst gaat over met hoeveel mensen u regelmatig afspreekt of praat,

    inclusief familie, vrienden, collega's, buren, etc. Lees en beantwoord elke vraag nauwkeurig.

    Beantwoord subvragen waar nodig.

    1. Welk van onderstaande alternatieven beschrijft je huwelijkse staat het best?

    .... (1) Op dit moment getrouwd en samenwonend, of samenwonend met een vaste relatie.

    .... (2) Nooit getrouwd geweest, en nooit samengewoond met een vaste relatie.

    .... (3) Uit elkaar.

    .... (4) Gescheiden, of voorheen samengewoond met iemand in een vaste relatie.

    .... (5) Weduwe/weduwnaar.

    2. Hoeveel kinderen heb je? (Als je geen kinderen hebt, schrijf dan '0' op en ga verder met

    vraag 3.)

    ....

    2a. Met hoeveel van je kinderen heb je minstens eens per twee weken contact?

    ....

    3. Zijn je vader en moeder nog in leven? (Als je beide ouders overleden zijn, zet dan eenkruisje bij '0' en ga verder met vraag 4.)

    .... (0) Geen van beide

    .... (1) Alleen moeder nog in leven

    .... (2) Alleen vader nog in leven

    .... (3) Beide nog in leven

    3a. Zie je of spreek je je vader en moeder minstens eens per twee weken?

    .... (0) Geen van beide

    .... (1) Alleen moeder

    .... (2) Alleen vader

    .... (3) Beide

    4. Leven je schoonvader en je schoonmoeder nog (of de ouders van je partner)? (Als je geen

    schoonouders hebt, zet dan een kruisje bij 'Niet van toepassing' en ga verder met vraag5.)

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    .... (0) Geen van beide

    .... (1) Alleen schoonmoeder leeft nog

    .... (2) Alleen schoonvader leeft nog

    .... (3) Beide leven nog

    .... (4) Niet van toepassing

    4a. Zie je of spreek je je schoonouders minstens eens per twee weken?

    .... (0) Geen van beide

    .... (1) Alleen schoonmoeder

    .... (2) Alleen schoonvader

    .... (3) Beide

    5.Aan hoeveel familieleden (anders dan uw echtgeno(o)t(e), ouders, en kinderen) voel je jegehecht? (Als dit er geen zijn, schrijf dan op '0', en ga verder met vraag 6.)

    ....

    5a. Hoeveel van deze familieleden zie je of spreek je minstens eens per twee weken?

    ....

    6. Hoeveel goede vrienden heb je? (met goede vrienden bedoelen we hier mensen bij wie u

    zich gemakkelijk voelt, met wie u over persoonlijke zaken kunt praten, en die u om hulp

    kunt vragen)

    ....

    6a. Hoeveel van deze vrienden zie je of spreek je minstens eens per twee weken?

    ....

    7.Ben je lid van een religieuze groep? (bv. een kerkgenootschap) Als dit niet het geval is, zetdan een kruisje bij 'nee' en ga verder met vraag 8.

    ... (1) Ja

    ... (2) Nee

    7a. Hoeveel leden van je religieuze groep spreek je minstens eens per twee weken?

    (Inclusief gesprekken rondom bijeenkomsten en diensten).

    ....

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    8. Volgt u regelmatig onderwijs (via een school, universiteit, technische training, of

    volwassenen onderwijs)? Zo niet, zet dan een kruisje bij 'nee' en ga door met vraag 9.

    ... (1) Ja

    ... (2) Nee

    8a. Hoeveel medestudenten of docenten spreek je minstens eens per twee weken?

    (Inclusief gesprekken rondom de lessen)

    ....

    9.Werkt u op dit moment voltijds of in deeltijd? (Als dit niet het geval is, zet dan een kruisjebij 'nee' en ga door met vraag 10.)

    .... (0) nee

    .... (1) ja, in mijn eigen bedrijf/als zelfstandig ondernemer

    .... (2) ja, in loondienst

    9a. Over hoeveel mensen heeft u de supervisie?

    ....

    9b. Hoeveel collega's (uitgezonderd hen die u superviseert) spreekt u minstens eens per

    twee weken?

    ....

    10.Hoeveel van je buren bezoek je of spreek je minstens eens per twee weken?....

    11.Verricht je op dit moment regelmatig vrijwilligerswerk? (Zo nee, zet dan een kruisje bij'nee' en ga verder met vraag 12.)

    ... (1) Ja

    ... (2) Nee

    11a. Hoeveel mensen die betrokken zijn bij dit vrijwilligerswerk spreek je minstens eens per

    twee weken over zaken die te maken hebben met het vrijwilligerswerk?

    ....

    12. Hoor je bij groepen waarin je met een of meerdere leden minstens eens per twee weken

    over groepsgerelateerde zaken praat? Voorbeelden van zulke groepen zijn onder andere

    gezelligheidsverenigingen; hobbyverenigingen; vakbonden; commercile groepen;

    beroepsorganisaties; groepen die te maken hebben met kinderen, zoals ouderverenigingenop scholen of scouting; groepen die te maken hebben met de gemeenschap waarin je

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    woont; etc. (Als je niet bij zulke groepen hoort, zet dan een kruisje bij 'nee' en sla het

    volgende deel van de vragenlijst over.)

    ... (1) Ja

    ... (2) Nee

    Bedenk in welke van deze groepen je minstens eens per twee weken met een groepslid

    praat, en geef de volgende informatie voor elke groep: De naam of het soort groep, en het

    totale aantal groepsleden in die groep met wie je minstens eens per twee weken praat.

    Naam/soort groep Aantal

    groepsleden

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    3. Dutch Translation of Social Network Size Questionnaire

    (adapted from Stileman & Bates, 2007)

    Hoeveel mensen waren er in totaal aanwezig op het feest voor je 18de

    of 21ste

    verjaardag?

    ....

    Als je nu een feestje zou geven, hoeveel mensen zou je dan uitnodigen?

    ....

    Wat is het totaal aantal vrienden in de contactlijst van je telefoon?

    ....

    Schrijf de namen op van alle mensen die je een sms-bericht zou sturen bij een feestelijke

    gebeurtenis (bijv. een verjaardag, Kerstmis, nieuwe baan, goed examenresultaat, etc.).Hoeveel mensen zijn dit in totaal?

    ....

    Schrijf de namen op van alle mensen in de contactlijst van je telefoon die je zou kunnen

    ontmoeten voor een praatje in een besloten groep van twee tot vier personen. Hoeveel

    mensen zijn dit in totaal?

    ....

    Met hoeveel vrienden uit je schooltijd zou je nu nog vriendschappelijk gesprek kunnen

    voeren?

    ....

    Hoeveel vrienden heb je op Facebook?

    ....

    Hoeveel vrienden heb je buiten de universiteit?

    ....

    Schrijf de namen op van alle mensen waarvan je vindt dat je ze om een gunst kan vragen in

    de verwachting dat die ook wordt verleend. Hoeveel mensen zijn dit in totaal?

    ....

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    4. Dutch Translation of Cognitive Failures Questionnaire

    (adapted from Broadbent et al., 1982)

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    5. Dutch Translation of Political Orientation Questionnaire

    (adapted from Kanai et al., 2011c)

    Geef alstublieft je politieke voorkeur aan door een van de onderstaande alternatieven te

    omcirkelen:

    (1) erg progressief

    (2) progressief

    (3) niet progressief maar ook niet conservatief

    (4) conservatief

    (5) erg conservatief

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    6. Dutch Translation ofMoral Foundations Questionnaire

    (adapted from Graham et al., 2009)

    Deel 1. Wanneer je besluit of iets goed of slecht is, in welke mate zijn de volgende overwegingen dan

    van belang voor jouw oordeel.

    [0] = Helemaal niet relevant (Deze overweging heeft niets te maken met mijn besluit over goed en

    slecht)

    [1] = Niet erg relevant

    [2] = Enigszins relevant

    [3] = Redelijk relevant

    [4] = Erg relevant

    [5] = Heel erg relevant (Dit is een van de belangrijkste factoren wanneer ik oordeel over goed en

    slecht)

    ______ Of iemand emotioneel heeft geleden

    ______ Of sommige mensen anders behandeld werden dan anderen

    ______ Of iemands daden liefde toonden voor zijn of haar land

    ______ Of iemand een gebrek aan respect voor autoriteit heeft getoond

    ______ Of iemand standaarden van puurheid en fatsoenlijkheid geschonden heeft______ Of iemand goed was in wiskunde

    ______ Of iemand zorgde voor een zwak of kwetsbaar iemand

    ______ Of iemand oneerlijk heeft gehandeld

    ______ Of iemand zijn of haar groep verraden heeft

    ______ Of iemand zich conformeerde aan de tradities van de maatschappij

    ______ Of iemand iets walgelijks heeft gedaan

    ______ Of iemand wreed was

    ______ Of iemands rechten zijn ontzegt

    ______ Of iemand een gebrek aan loyaliteit heeft getoond

    ______ Of iemands actie chaos of wanorde veroorzaakte

    ______ Of iemand zich gedroeg op een wijze die God zou goedkeuren

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    Deel 2: Zou je voor de volgende stellingen aan willen geven in welke mate je het ermee eens of

    oneens bent.

    [0] [1] [2] [3] [4] [5]

    zeer mee

    oneens

    redelijk mee

    oneens

    enigszins mee

    oneens

    enigszins mee

    eens

    redelijk mee

    eens

    zeer mee

    eens

    ______ Medeleven met degenen die lijden, is de belangrijkste deugd.

    ______ Wanneer de overheid wetten maakt, dan moet de garantie dat iedereen eerlijk behandeld

    wordt het belangrijkste principe zijn.

    ______ Ik ben trots op de geschiedenis van mijn land.______ Respect voor autoriteit is iets dat alle kinderen moeten leren.

    ______ Mensen behoren geen walgelijke dingen te doen, zelfs wanneer er niemand schade

    berokkend wordt.

    ______ Het is beter iets goeds te doen dan iets slechts.

    ______ Een van de ergste dingen die een mens kan doen is een weerloos dier pijn doen.

    ______ Rechtvaardigheid is de belangrijkste behoefte voor een maatschappij.

    ______ Mensen behoren loyaal te zijn aan hun familieleden, zelfs wanneer zij iets slechts hebben

    gedaan.

    ______ Mannen en vrouwen hebben elk verschillende rollen in de maatschappij.

    ______ Ik vind sommige daden slecht, omdat zij onnatuurlijk zijn.

    ______ Het kan nooit goed zijn om een mens te doden.

    ______ Ik vind dat het moreel onjuist is dat rijke kinderen een heleboel geld erven, terwijl arme

    kinderen niets erven.

    ______ Het is belangrijker om een teamspeler te zijn dan om jezelf te uiten.

    ______ Als ik een soldaat was en ik was het oneens met de orders van mijn leidinggevende, dan zou

    ik toch gehoorzamen omdat dit mijn plicht is.

    ______ Kuisheid is een belangrijke en waardevolle deugd.

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    7. Dutch Translation ofInterpersonal Reactivity Index

    (adapted from Davis, 1980)

    Instructies:

    Onderstaand vindt je een aantal beweringen. De bedoeling is dat je deze beweringen

    doorleest en dat je nagaat of zij jou goed beschrijven.

    Hieronder staan vier antwoordmogelijkheden die variren van "beschrijft mij heel goed" tot

    "beschrijft mij helemaal niet goed". Het is de bedoeling dat je telkens met een letter voor de

    zin aangeeft in hoeverre een bewering jou goed beschrijft.

    Laat geen vraag onbeantwoord en beperk je tot de gegeven antwoordmogelijkheden.

    Neem je tijd, maar denk niet al te lang na over een vraag.

    Antwoordmogelijkheden:

    A B C D E

    Beschrijft mij Beschrijft mij

    helemaal niet heel

    goed goed

    Beweringen:

    ______Ik dagdroom en fantaseer, met enige regelmaat, over dingen die zouden kunnen

    gebeuren met mij.

    ______Ik heb vaak tedere, bezorgde gevoelens voor mensen die minder gelukkig zijn dan ik.

    ______Ik vind het soms moeilijk om dingen te zien vanuit andermans gezichtspunt.

    ______Soms heb ik niet veel medelijden met andere mensen wanneer ze problemen

    hebben.

    ______Ik raak echt betrokken bij de gevoelens van de personages uit een roman.

    ______In noodsituaties voel ik me ongerust en niet op mijn gemak.

    ______Ik ben meestal objectief wanneer ik naar een film of toneelstuk kijk, en ik ga er niet

    vaak volledig in op.

    ______Ik probeer naar ieders kant van een meningsverschil te kijken alvorens ik een

    beslissing neem.

    ______Wanneer ik iemand zie waarvan wordt geprofiteerd, voel ik me nogal beschermend

    tegenover hen.

    ______Ik voel me soms hulpeloos wanneer ik in het midden van een zeer emotionele

    situatie ben.

    ______Ik probeer mijn vrienden soms beter te begrijpen door me in te beelden hoe de

    dingen eruit zien vanuit hun perspectief.

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    ______Uitermate betrokken geraken in een goed boek of film is eerder zeldzaam voor mij.

    ______Wanneer ik zie dat iemand zich bezeert, ben ik geneigd kalm te blijven.

    ______Andermans ongelukken verstoren me meestal niet veel.

    ______Als ik zeker ben dat ik over iets gelijk heb, verspil ik niet veel tijd aan het luisteren

    naar andermans argumenten.

    ______Na het zien van een toneelstuk of film, heb ik mij gevoeld alsof ik een van de

    karakters was.

    ______In een gespannen emotionele situatie zijn, schrikt me af.

    ______Wanneer ik zie dat iemand unfair wordt behandeld, voel ik soms weinig medelijden

    met hen.

    ______Ik ben meestal behoorlijk effectief in het omgaan met noodsituaties.

    ______Ik ben vaak nogal geraakt door dingen die ik zie gebeuren.

    ______ Ik geloof dat er twee zijden zijn aan elke vraag en probeer te kijken naar hun beide.

    ______Ik zou mijzelf beschrijven als een vrij teerhartig persoon.

    ______Wanneer ik naar een goede film kijk, kan ik mezelf zeer gemakkelijk in de plaats

    stellen van het hoofdpersonage.

    ______Ik neig ertoe controle te verliezen tijdens noodsituaties.

    ______Wanneer ik overstuur ben door iemand, probeer ik mijzelf meestal voor een tijdje in

    zijn schoenen te verplaatsen.

    ______Wanneer ik een interessant verhaal of roman aan het lezen ben, beeld ik me in hoe

    ik me zou voelen indien de gebeurtenissen in het verhaal mij zouden overkomen.

    ______Wanneer ik iemand zie die zeer hard hulp nodig heeft in een noodsituatie, ga ik

    kapot.

    ______Alvorens iemand te bekritiseren, probeer ik mij voor te stellen hoe ik mij zou voelen

    mocht ik in hun plaats zijn.

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