How Mean is the Mean?

From means to meaning in the study of sex/gender differences and similarities

The incorporation of sex and gender (S/G) related factors is commonly acknowledged as a necessary step to advance towards more personalized diagnoses and treatments for somatic, psychiatric, and neurological diseases. Until now, most attempts to integrate S/G-related factors have been reduced to identifying average differences between females and males in behavioral/ biological variables. The present commentary questions this traditional approach by highlighting three main sets of limitations: 1) Issues stemming from the use of classic parametric methods to compare means; 2) challenges related to the ability of means to accurately represent the data within groups and differences between groups; 3) mean comparisons impose a results' binarization and a binary theoretical framework that precludes advancing towards precision medicine. Alternative methods free of these limitations are also discussed. We hope these arguments will contribute to reflecting on how research on S/G factors is conducted and could be improved.

The reliability of a linear position transducer for measuring countermovement jump performance in national-level road cyclists

BACKGROUND

Jump tests have applications in fatigue monitoring, training intervention evaluations, and talent identification in cycling populations. Due to competitive cycling's inherent travel demands, linear position transducers (LPTs) are suitable for assessing jump performance in this population as they are a mobile and validated technology. Understanding the reliability and sensitivity of LPTs in assessing jump performance in cycling populations is required to support the development of sports science protocols. Using an LPT, this study aimed to determine the reliability and sensitivity of countermovement jump (CMJ) variables in road cyclists.

METHODS

Ten national-level male road cyclists performed three maximal CMJ trials twice per week for two weeks, with an LPT measuring force, power, velocity, repetition rate, vertical distance, and concentric time from each trial. Using the mean and best CMJ results from three trials per testing session, the upper limit 90% confidence interval for the coefficient of variation (CV) and smallest worthwhile change (SWC) determined inter-day and -week reliability (CV ≤ 10%) and sensitivity (acceptable sensitivity = CV ≤ SWC) for CMJ variables.

RESULTS

Mean power and force, velocity (mean and peak), vertical distance (VD), and concentric time had acceptable inter-day and -week reliability when using either the mean or best CMJ results (CV upper limit 90% confidence interval range = 3.54-10.13%). Moreover, the CV and SWC were typically lower when based on the mean rather than the best of three CMJ trials. Lastly, poor sensitivity (CV > SWC) was evident for all CMJ variables.

CONCLUSIONS

CMJ-derived mean power and force, velocity (peak and mean), VD, and concentric time have acceptable inter-day and -week reliability when assessed via an LPT in national-level road cyclists. When using an LPT, sports scientists should consider that, while they typically have poor sensitivity, the reliability of CMJ-derived variables improves when expressed as the mean of three trials in national-level road cyclists.

The functional role of visual information and fixation stillness in the quiet eye

The final fixation to a target in far-aiming tasks, known as the quiet eye, has been consistently identified as an important perceptual-cognitive variable for task execution. Yet, despite a number of proposed mechanisms it remains unclear whether the fixation itself is driving performance effects or is simply an emergent property of underpinning cognitions. Across two pre-registered studies, novice golfers (n = 127) completed a series of golf putts in a virtual reality simulation to examine the function of the quiet eye in the absence of visual information. In experiment 1 participants maintained a quiet eye fixation even when all visual information was occluded. Visual occlusion did significantly disrupt motor skill accuracy, but the effect was relatively small (89cm vs 105cm radial error, std. beta = 0.25). In experiment 2, a 'noisy eye' was induced using covertly moving fixation points, which disrupted skill execution (p = .04, BF = 318.07, std. beta = -0.25) even though visual input was equivalent across conditions. Overall, the results showed that performers persist with a long pre-shot fixation even in the absence of visual information, and that the stillness of this fixation confers a functional benefit that is not merely related to improved information extraction.

Dismantling and personalising task-sharing psychosocial interventions for common mental disorders: a study protocol for an individual participant data component network meta-analysis

INTRODUCTION

Common mental disorders, including depression, anxiety and related somatic health symptoms, are leading causes of disability worldwide. Especially in low-resource settings, psychosocial interventions delivered by non-specialist providers through task-sharing modalities proved to be valid options to expand access to mental healthcare. However, such interventions are usually eclectic multicomponent interventions consisting of different combinations of evidence-based therapeutic strategies. Which of these various components (or combinations thereof) are more efficacious (and for whom) to reduce common mental disorder symptomatology is yet to be substantiated by evidence.

METHODS AND ANALYSIS

Comprehensive search was performed in electronic databases MEDLINE, Embase, PsycINFO and the Cochrane Register of Controlled Trials-CENTRAL from database inception to 15 March 2023 to systematically identify all randomised controlled trials that compared any single component or multicomponent psychosocial intervention delivered through the task-sharing modality against any active or inactive control condition in the treatment of adults suffering from common mental disorders. From these trials, individual participant data (IPD) of all measured outcomes and covariates will be collected. We will dismantle psychosocial interventions creating a taxonomy of components and then apply the IPD component network meta-analysis (IPD-cNMA) methodology to assess the efficacy of individual components (or combinations thereof) according to participant-level prognostic factors and effect modifiers.

ETHICS AND DISSEMINATION

Ethics approval is not applicable for this study since no original data will be collected. Results from this study will be published in peer-reviewed journals and presented at relevant conferences.

Using Constrained-Disorder Principle-Based Systems to Improve the Performance of Digital Twins in Biological Systems

Digital twins are computer programs that use real-world data to create simulations that predict the performance of processes, products, and systems. Digital twins may integrate artificial intelligence to improve their outputs. Models for dealing with uncertainties and noise are used to improve the accuracy of digital twins. Most currently used systems aim to reduce noise to improve their outputs. Nevertheless, biological systems are characterized by inherent variability, which is necessary for their proper function. The constrained-disorder principle defines living systems as having a disorder as part of their existence and proper operation while kept within dynamic boundaries. In the present paper, we review the role of noise in complex systems and its use in bioengineering. We describe the use of digital twins for medical applications and current methods for dealing with noise and uncertainties in modeling. The paper presents methods to improve the accuracy and effectiveness of digital twin systems by continuously implementing variability signatures while simultaneously reducing unwanted noise in their inputs and outputs. Accounting for the noisy internal and external environments of complex biological systems is necessary for the future design of improved, more accurate digital twins.

Does lateral banking and radius affect well-trained sprinters and team-sports players during bend sprinting?

This study investigated the short-term responses of step characteristics in sprinters and team-sports players under different bend conditions. Eight participants from each group completed 80 m sprints in four conditions: banked and flat, in lanes two and four (L2B, L4B, L2F, L4F). Groups showed similar changes in step velocity (SV) across conditions and limbs. However, sprinters produced significantly shorter ground contact times (GCT) than team sports players in L2B and L4B for both left (0.123 s vs 0.145 s and 0.123 s vs 0.140 s) and right steps (0.115 s vs 0.136 s and 0.120 s vs 0.141 s) (p > 0.001-0.029; ES = 1.15-1.37). Across both groups, SV was generally lower in flat conditions compared to banked (Left: 7.21 m/s vs 6.82 m/s and Right: 7.31 m/s vs 7.09 m/s in lane two), occurring due to reduced step length (SL) rather than step frequency (SF), suggesting that banking improves SV via increased SL. Sprinters produced significantly shorter GCT in banked conditions that led to non-significant increases in SF and SV, highlighting the importance of bend sprinting specific conditioning and training environments representative of indoor competition for sprint athletes.

Large-scale study of the precision of the approximate number system: Differences between formats, heterogeneity and congruency effects

The study used a large sample of elementary schoolchildren in Russia (N = 3,448, 51.6% were girls, with a mean age of 8.70 years, ranging 6-11 years) to investigate the congruency, format and heterogeneity effects in a nonsymbolic comparison test and between-individual differences in these effects with generalized linear mixed effects models (GLMMs). The participants were asked to compare two arrays of figures of different colours in spatially separated or spatially intermixed formats. In addition, the figures could be similar or different for the two arrays. The results revealed that congruency (difference between congruent and incongruent items), format (difference between mixed and separated formats) and heterogeneity (difference between homogeneous and heterogeneous conditions) interacted. The heterogeneity effect was higher in the separated format, while the format effect was higher for the homogeneous condition. The separated format produced a greater congruency effect than the mixed format. In addition, the congruency effect was lower in the heterogeneous condition than in the homogeneous condition. Analysis of between-individual differences revealed that there was significant between-individual variance in the format and congruency effects. Analysis of between-grade differences revealed that accuracy improved from grade 1 to grade 4 only for congruent trials in separated formats. Consequently, the congruency effect increased in separated/homogeneous and separated/heterogeneous conditions. In general, the study demonstrated that the test format and heterogeneity affected accuracy and that this effect varied for congruent and incongruent items.

Making use of noise in biological systems

Disorder and noise are inherent in biological systems. They are required to provide systems with the advantages required for proper functioning. Noise is a part of the flexibility and plasticity of biological systems. It provides systems with increased routes, improves information transfer, and assists in response triggers. This paper reviews recent studies on noise at the genome, cellular, and whole organ levels. We focus on the need to use noise in system engineering. We present some of the challenges faced in studying noise. Optimizing the efficiency of complex systems requires a degree of variability in their functions within certain limits. Constrained noise can be considered a method for improving system robustness by regulating noise levels in continuously dynamic settings. The digital pill-based artificial intelligence (AI)-based platform is the first to implement second-generation AI comprising variability-based signatures. This platform enhances the efficacy of the therapeutic regimens. Systems requiring variability and mechanisms regulating noise are mandatory for understanding biological functions.

Neural and cognitive correlates of performance in dynamic multi-modal settings

The endeavour to understand human cognition has largely relied upon investigation of task-related brain activity. However, resting-state brain activity can also offer insights into individual information processing and performance capabilities. Previous research has identified electroencephalographic resting-state characteristics (most prominently: the individual alpha frequency; IAF) that predict cognitive function. However, it has largely overlooked a second component of electrophysiological signals: aperiodic 1/ƒ activity. The current study examined how both oscillatory and aperiodic resting-state EEG measures, alongside traditional cognitive tests, can predict performance in a dynamic and complex, semi-naturalistic cognitive task. Participants' resting-state EEG was recorded prior to engaging in a Target Motion Analysis (TMA) task in a simulated submarine control room environment (CRUSE), which required participants to integrate dynamically changing information over time. We demonstrated that the relationship between IAF and cognitive performance extends from simple cognitive tasks (e.g., digit span) to complex, dynamic measures of information processing. Further, our results showed that individual 1/ƒ parameters (slope and intercept) differentially predicted performance across practice and testing sessions, whereby flatter slopes and higher intercepts were associated with improved performance during learning. In addition to the EEG predictors, we demonstrate a link between cognitive skills most closely related to the TMA task (i.e., spatial imagery) and subsequent performance. Overall, the current study highlights (1) how resting-state metrics - both oscillatory and aperiodic - have the potential to index higher-order cognitive capacity, while (2) emphasising the importance of examining these electrophysiological components within more dynamic settings and over time.

Exploring Old Data with New Tricks: Long-Term Monitoring Indicates Spatial and Temporal Changes in Populations of Sympatric Prairie Grouse in the Nebraska Sandhills

The contiguous grasslands of the Sandhills region in Nebraska, USA, provide habitat for two sympatric, grassland-obligate species of grouse, the greater prairie-chicken (Tympanuchus cupido pinnatus) and the plains sharp-tailed grouse (Tympanuchus phasianellus jamesi). Collectively referred to as prairie grouse, these birds are monitored and managed jointly by wildlife practitioners who face the novel challenge of conserving historically allopatric species in shared range. We reconstructed region-wide and route-specific prairie grouse population trends in the Sandhills, using a 63-year timeseries of breeding ground counts aggregated from old reports and paper archives. Our objective was to repurpose historical data collected for harvest management to address questions pertinent to the conservation of prairie grouse, species whose populations have declined precipitously throughout their respective ranges. Because we cannot change the sampling protocol of historical data to answer new questions, we applied 3 different methods of data analysis—traditional regional mean counts used to adjust harvest regulations, spatially implicit, site-specific counts, and spatially explicit trends. Prairie-chicken populations have increased since the 1950s, whereas sharp-tailed grouse populations have remained stable or slightly declined. However, each species exhibited unique shifts in abundance and distribution over time, and regional indices masked important aspects of population change. Our findings indicate that legacy data have the capacity to tell new stories apart from the questions they were collected to answer. By integrating concepts from landscape ecology—a discipline that emerged decades after the collection of our count data began—we demonstrate the potential of historical data to address questions of modern-day conservation concern, using prairie grouse as a case study.

Effect of a sex stereotype on cortical activity during a self-paced exercise: A motor-related cortical potential approach

Recent research has shown that inducing a negative stereotype toward women does not always decrease the subsequent motor performance of women, but can increase it, especially during endurance tasks. The mechanisms involved are nonetheless still poorly understood. The main aim of the present study was to investigate the effect of a negative stereotype toward women on men's and women's performance during an endurance task, and to analyze the neuropsychological mechanisms involved through motor-related cortical potentials and motivation toward men/women. Thirty-four participants were assigned to a negative stereotype toward women condition and a nullified-stereotype condition and performed 80 self-paced intermittent isometric elbow contractions at a moderate perceived intensity. Results showed that women performed better when assigned to the negative stereotype toward women condition, they were more motivated to outperform men, and their MRCP amplitudes were higher in this same condition over the prefrontal cortex (i.e., FP1 and FP2). Concerning men, they also performed better when the negative stereotype toward women was induced. However, no effect emerged on motivation toward women and MRCP amplitudes. This study showed that inducing a negative stereotype during an endurance task led to a performance increase in women, which is contrary to the stereotype threat theory, strengthening the idea of a task-dependency effect when inducing a negative stereotype. This performance improvement observed in women may be caused by increased motivation to outperform men and a planning of the upcoming movement. Concerning men, more research is needed to clarify the mechanisms involved in such performance improvement.

Gender stereotypes and motor performance: How explicit and implicit stereotypes influence girls standing long jump and anxiety

OBJECTIVES

Inducing a negative stereotype toward women usually leads to a decrease in women's motor performance. Given that most studies have focused on explicit stereotype induction among adults, the main aim of this study was to investigate the effects of explicit and implicit gender stereotypes on standing long jump performance in children. The second aim was to investigate the effects of these same manipulations on children's state anxiety.

DESIGN

A mixed model design with within-between-subject was used with standing long jump performance and state anxiety as dependent variables.

METHOD

Two hundred and four children (Mage = 10.95 years, SDage = 0.85) participated in this study and were randomly assigned, after baseline measurement, into four different groups (i.e., explicit/implicit vs. explicit vs. implicit vs. control). Specifically, participants performed 8 trials of standing long jump (4 trials during the baseline phase and 4 trials during the experimental phase). Children also completed the competitive state Anxiety Inventory at baseline as well as immediately after the trials.

RESULTS

For motor performance, children in the explicit/implicit group and in the implicit group were negatively affected by the stereotype manipulation during all trials whereas participants in the explicit group were only negatively impacted during the last two trials. However, regarding state anxiety, children were negatively affected after both explicit only and implicit only manipulations and more significantly after explicit/implicit manipulation.

CONCLUSIONS

The present research showed that the explicit and implicit manipulations influenced motor performance differently, but that these two manipulations increased state anxiety in the same way. Moreover, the combination of the explicit and implicit inductions leads to a greater significant negative influence on state anxiety but not motor performance.

The Cognitive Profile of Math Difficulties: A Meta-Analysis Based on Clinical Criteria

Math difficulties (MD) manifest across various domain-specific and domain-general abilities. However, the existing cognitive profile of MD is incomplete and thus not applicable in typical settings such as schools or clinics. So far, no review has applied inclusion criteria according to DSM or ICD, summarized domain-specific abilities or examined the validity of response time scores for MD identification. Based upon stringent clinical criteria, the current meta-analysis included 34 studies which compared cognitive performances of a group with MD (n = 680) and a group without MD (n = 1565). Criteria according to DSM and ICD were applied to identify MD (percentile rank ≤ 16, age range 8–12 years, no comorbidities/low IQ). Effect sizes for 22 abilities were estimated and separated by their level and type of scoring (AC = accuracy, RT = response time). A cognitive profile of MD was identified, characterized by distinct weaknesses in: (a) computation (calculation [AC], fact retrieval [AC]), (b) number sense (quantity processing [AC], quantity-number linking [RT], numerical relations [AC]), and (c) visual-spatial short-term storage [AC]. No particular strength was found. Severity of MD, group differences in reading performance and IQ did not significantly moderate the results. Further analyses revealed that (a) effects are larger when dealing with numbers or number words than with quantities, (b) MD is not accompanied by any weakness in abilities typically assigned to reading, and (c) weaknesses in visual-spatial short-term storage emphasize the notion that number and space are interlinked. The need for high-quality studies investigating domain-general abilities is discussed.

Training Coaches in Community Agencies to Support Parents of Children with Suspected Autism: Outcomes, Facilitators, and Barriers

This study evaluated the fidelity and effectiveness of a parent coach training program for toddlers at risk for autism spectrum disorder and identified factors required for successful training implementation under real-world conditions. Training addressed four tiers of clinical competence and was delivered to early intervention providers across 23 partner agencies in a large Canadian province. Results indicated that mean trainee fidelity scores were within the range reported in previous community-based training studies but there was considerable variability across trainees. Implementation facilitators included agency learning climate, leadership support, and trainee readiness for change. Implementation barriers included time/caseload demands and challenges related to technology learning and infrastructure. Results have implications for parent coach training in community settings.

High spatial frequency filtered primes hastens happy faces categorization in autistic adults

Coarse information of a visual stimulus is conveyed by Low Spatial Frequencies (LSF) and is thought to be rapidly extracted to generate predictions. This may guide fast recognition with the subsequent integration of fine information, conveyed by High Spatial Frequencies (HSF). In autism, emotional face recognition is challenging, and might be related to alterations in LSF predictive processes. We analyzed the data of 27 autistic and 34 non autistic (NA) adults on an emotional Stroop task (i.e., emotional face with congruent or incongruent emotional word) with spatially filtered primes (HSF vs.LSF). We hypothesized that LSF primes would generate predictions leading to faster categorization of the target face compared to HSF primes, in the NA group but not in autism. Surprisingly, HSF primes led to faster categorization than LSF primes in both groups. Moreover, the advantage of HSF vs.LSF primes was stronger for angry than happy faces in NA, but was stronger for happy than angry faces in autistic participants. Drift diffusion modelling confirmed HSF advantage and showed a longer non-decision time (e.g., encoding) in autism. Despite LSF predictive impairments in autism was not corroborated, our analyses suggest low level processing specificities in autism.

On Educational Assessment Theory: A High-Level Discussion of Adolphe Quetelet, Platonism, and Ergodicity

Educational assessments, specifically standardized and normalized exams, owe most of their foundations to psychological test theory in psychometrics. While the theoretical assumptions of these practices are widespread and relatively uncontroversial in the testing community, there are at least two that are philosophically and mathematically suspect and have troubling implications in education. Assumption 1 is that repeated assessment measures that are calculated into an arithmetic mean are thought to represent some real stable, quantitative psychological trait or ability plus some error. Assumption 2 is that aggregated, group-level educational data collected from assessments can then be interpreted to make inferences about a given individual person over time without explicit justification. It is argued that the former assumption cannot be taken for granted; it is also argued that, while it is typically attributed to 20th century thought, the assumption in a rigorous form can be traced back at least to the 1830s via an unattractive Platonistic statistical thesis offered by one of the founders of the social sciences—Belgian mathematician Adolphe Quetelet (1796–1874). While contemporary research has moved away from using his work directly, it is demonstrated that cognitive psychology is still facing the preservation of assumption 1, which is becoming increasingly challenged by current paradigms that pitch human cognition as a dynamical, complex system. However, how to deal with assumption 1 and whether it is broadly justified is left as an open question. It is then argued that assumption 2 is only justified by assessments having ergodic properties, which is a criterion rarely met in education; specifically, some forms of normalized standardized exams are intrinsically non-ergodic and should be thought of as invalid assessments for saying much about individual students and their capability. The article closes with a call for the introduction of dynamical mathematics into educational assessment at a conceptual level (e.g., through Bayesian networks), the critical analysis of several key psychological testing assumptions, and the introduction of dynamical language into philosophical discourse. Each of these prima facie distinct areas ought to inform each other more closely in educational studies.

Does the Effect of Stereotypes in Older People Depend Upon Task Intensity?

This study examined the effect of negative and positive stereotypes on the strength produced by older adults at different perceived effort intensities, reflecting different levels of task difficulty. Fifty older women were randomly assigned to a positive stereotype, a negative stereotype, or a control condition. Before (T1) and after (T2) the stereotype manipulation, they were asked to perform a voluntary isometric contraction at a level of muscular effort that corresponded to four perceived effort intensities ("easy," "moderate," hard" and "very hard"). Results showed that participants attained greater strength during the easy and hard tasks after exposure to both positive and negative stereotypes. At the moderate and very hard intensities, stereotype induction did not significantly change the strength from the baseline performance. While these results are not fully in line with the stereotype threat theory, they provide evidence that task difficulty could modulate the effect of aging stereotypes during physical tasks.

Object affordances from the perspective of an avatar

Humans often interact with avatars in video gaming, workplace, or health applications, for instance. The present research studied object affordances from an avatar's perspective. In two experiments, participants responded to objects with a left/right keypress, indicating whether the objects were upright or inverted. Task-irrelevant objects' handles were aligned with either the left or right hand of the actor and/or avatar. We hypothesized that actors respond faster when the handles are aligned, as compared to non-aligned, with the respective avatar hand (spatial alignment effect or object-based Simon effect). In Experiment 1, the spatial alignment effect was increased through the presentation of avatar hands as compared to when no hands were presented. In Experiment 2, the avatar perspective was rotated by 90° to the right and left of the actor's view. Here, the spatial alignment effect was guided by the avatar, suggesting that the actors took its perspective when perceiving objects' affordances.

Sentence Recall in Latent and Anomic Aphasia: An Exploratory Study of Semantics and Syntax

We investigated whether semantic plausibility and syntactic complexity affect immediate sentence recall in people with latent and anomic aphasia. To date, these factors have not been explored in these types of aphasia. As with previous studies of sentence recall, we measured accuracy of verbatim recall and uniquely real-time speech measures. The results showed that accuracy did not distinguish performance between latent aphasia and neurotypical controls. However, some of the real-time speech measures distinguished performance between people with latent aphasia and neurotypical controls. There was some evidence, though not pervasive, that semantic plausibility and syntactic complexity influenced recall performance. There were no interactions between semantic plausibility and syntactic complexity. The speed of preparation of responses was slower in latent aphasia than controls; it was also slower in anomic aphasia than both latent and control groups. It appears that processing speed as indexed by temporal speech measures may be differentially compromised in latent and anomic aphasia. However, semantic plausibility and syntactic complexity did not show clear patterns of performance among the groups. Notwithstanding the absence of interactions, we advance an explanation based on conceptual short-term memory as to why semantically implausible sentences are typically more erroneous and possibly also slower in recall.

Changes in BOLD variability are linked to the development of variable response inhibition

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This is the first study to investigate the development of response inhibition focussing on variability.

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We examined intraindividual variability both in stopping latencies and the underlying neural circuitry.

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There were no developmental differences in mean response inhibition, yet clear differences in performance variability.

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This, in turn, was associated with developmental differences in brain signal variability.

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Behavioral and neural variability indices might be a more sensitive measure of developmental differences in inhibition.

Research on the development of response inhibition in humans has focused almost exclusively on average stopping performance. The development of intra-individual variability in stopping performance and its underlying neural circuitry has remained largely unstudied, even though understanding variability is of core importance for understanding development. In a total sample of 45 participants (19 children aged 10–12 years and 26 adults aged 18–26 years) of either sex we aimed to identify age-related changes in intra-individual response inhibition performance and its underlying brain signal variability. While there was no difference in average stopping performance between children and adults, stop signal latencies for the children were more variable. Further, brain signal variability during successful stopping was significantly higher in adults compared to children, especially in bilateral thalamus, but also across regions of the inhibition network. Finally, brain signal variability was significantly associated with stopping performance behavioral variability in adults. Together these results indicate that variability in stopping performance decreases, whereas neural variability in the inhibition network increases, from childhood to adulthood. Future work will need to assess whether developmental changes in neural variability drive those in behavioral variability. In sum, both, neural and behavioral variability indices might be a more sensitive measure of developmental differences in response inhibition compared to the standard average-based measurements.

Exploring Idiographic Approaches to Children's Executive Function Performance: An Intensive Longitudinal Study

Traditional variable-centered research on executive functions (EFs) often infers intraindividual development using group-based averages. Such a method masks meaningful individuality and involves the fallacy of equating group-level data with person-specific changes. We used an intensive longitudinal design to study idiographic executive function fluctuation among ten boys from Grade 4. Each of the participants completed between 33 and 43 measurement occasions (M = 38.8) across approximately three months. Data were collected remotely using a computerized short version of the Dimensional Change Card Sort task. Multi-group analyses of three participant pairs (Participants 5 and 3, 5 and 2, and 5 and 6) demonstrated that Participant 5 differed from Participants 3 and 2 in different ways but Participants 5 and 6 were similar in all comparisons. Dynamic structural equation modeling demonstrated unique individual trajectories, which were not represented by the trajectory of group-averages. Although more than half of the participants showed a negative association between EFs and inattention, two participants showed a positive association between EF and inattention. This study demonstrated meaningful person-specific trajectories of EFs, suggesting that future study should undertake the analysis of individual development before data-aggregation or generalization from aggregate statistics to individuals.

Empathy trajectories throughout medical school: relationships with personality and motives for studying medicine

Empathy remains a widely discussed topic within medical education research. Studies on empathy changes among medical students are not univocal: empathy may decline, remain stable or increase. A largely unexplored research question regards inter-individual variability in empathy change, namely if different longitudinal trajectories of empathy exist. Evidence on the association of empathy trajectories with personality and motives for studying medicine is also scarce. Here, latent growth modeling examined empathy (measured with the Jefferson Scale of Empathy) among 201 medical students (M_age = 20.74, 57% females) across three assessments: at entry year (Year 1) and during the first two clinical years (Years 4 and 5). Associations between empathy trajectories, personality in Year 1 and motives for studying medicine in Years 4 and 5 were tested. We identified two empathy trajectory groups: lower and decreasing (n = 59; 29%) and higher and stable (n = 142; 71%). Regression analyses indicated that higher openness in Year 1 was associated with an increased probability of higher and stable group membership (controlling for motives in Year 1). The effect of openness disappeared controlling for motives in Years 4 and 5 while caring for patients (in Years 4 and 5) and altruism (in Year 4) were positively associated with an increased probability of higher and stable group membership. In sum, we observed that empathy remains stable in most medical students and declines in fewer; openness and patients-oriented motives for studying medicine are associated with higher and stable empathy. Encouraging medical students' patients-oriented motives from preclinical throughout clinical years may prevent empathy decline.

Statements About the Pervasiveness of Behavior Require Data About the Pervasiveness of Behavior

Despite recent close attention to issues related to the reliability of psychological research (e.g., the replication crisis), issues of the validity of this research have not been considered to the same extent. This paper highlights an issue that calls into question the validity of the common research practice of studying samples of individuals, and using sample-based statistics to infer generalizations that are applied not only to the parent population, but to individuals. The lack of ergodicity in human data means that such generalizations are not justified. This problem is illustrated with respect to two common scenarios in psychological research that raise questions for the sorts of theories that are typically proposed to explain human behavior and cognition. The paper presents a method of data analysis that requires closer attention to the range of behaviors exhibited by individuals in our research to determine the pervasiveness of effects observed in sample data. Such an approach to data analysis will produce results that are more in tune with the types of generalizations typical in reports of psychological research than mainstream analysis methods.

A New Empirical Approach to Intercultural Comparisons of Value Preferences Based on Schwartz's Theory

Empirical tests of Schwartz’s theory of culture-level value priorities have predominantly been performed using an averaging approach–as values of the average individual in a culture. However, from a theory of measurement standpoint such an approach seems inadequate. We argue that the averaging approach is an insufficiently accurate methodology in capturing the compatibilities-incompatibilities between values of individuals within cultures. We propose an approach based on the distribution of values of individuals in a given culture–the distribution approach. Using data from two rounds of the European Social Survey, we show how frequencies of specific individual value priorities in a culture can be used toward the description of culture-level value preferences. We recommend a re-conceptualization of Schwartz’s culture-level value theory to an orthogonal two-dimensional structure, namely as Alteration vs. Preservation and Amenability vs. Dominance, which we explain based on heterogeneity in socioecological indicators across countries. We conclude that societal challenges may influence the cultural value climate across countries.

BOLD and EEG signal variability at rest differently relate to aging in the human brain

Variability of neural activity is regarded as a crucial feature of healthy brain function, and several neuroimaging approaches have been employed to assess it noninvasively. Studies on the variability of both evoked brain response and spontaneous brain signals have shown remarkable changes with aging but it is unclear if the different measures of brain signal variability - identified with either hemodynamic or electrophysiological methods - reflect the same underlying physiology. In this study, we aimed to explore age differences of spontaneous brain signal variability with two different imaging modalities (EEG, fMRI) in healthy younger (25 ​± ​3 years, N ​= ​135) and older (67 ​± ​4 years, N ​= ​54) adults. Consistent with the previous studies, we found lower blood oxygenation level dependent (BOLD) variability in the older subjects as well as less signal variability in the amplitude of low-frequency oscillations (1-12 ​Hz), measured in source space. These age-related reductions were mostly observed in the areas that overlap with the default mode network. Moreover, age-related increases of variability in the amplitude of beta-band frequency EEG oscillations (15-25 ​Hz) were seen predominantly in temporal brain regions. There were significant sex differences in EEG signal variability in various brain regions while no significant sex differences were observed in BOLD signal variability. Bivariate and multivariate correlation analyses revealed no significant associations between EEG- and fMRI-based variability measures. In summary, we show that both BOLD and EEG signal variability reflect aging-related processes but are likely to be dominated by different physiological origins, which relate differentially to age and sex.

Testing the ego-depletion effect in optimized conditions

The observation that exerting self-control in an initial task impairs subsequent self-control performance in a following task has been used to explain a wide range of phenomena. If evidence for this "ego-depletion" effect was initially believed to be strong, it is now questioned. Recent meta-analyses indicated that this effect was sensitive to publication bias and that it was greatly reduced after control for this bias. In a pre-registered replication attempt where an ego-depletion protocol was conducted in multiple independent laboratories, the effect was not distinguishable from zero. Here, a different approach is adopted to examine the validity of this effect by improving the experimental protocol with the addition of important methodological precautions: 1) a pre-test measurement, 2) a learning period, 3) a prolonged depleting task, 4) a similar control condition, and 5) valid indexes of self-control. Accordingly, a well-learned Simon task was done before and after 1h of continuous practice of a Stroop task in a high inhibition demands condition (75% of incongruent trials) or in a control condition (0% of incongruent trials). Datasets from between-subjects (Study 1, N = 82) and within-subjects (Study 2, N = 52) experiments were analyzed using generalized linear mixed models. A significant ego-depletion effect was found in Study 1 (greater interference effect and accuracy decline in high inhibition demands than in control condition) but not in Study 2. Because it is difficult to explain this difference in results, the findings suggest that, even in a context chosen to optimize the observation of an ego-depletion effect, it seems difficult to be conclusive about the existence of this effect.

Measurability, systematic error, and the replication crisis: A reply to Michell (2019) and Krantz and Wallsten (2019)

Although Krantz and Wallsten (2019) claim that interval and ratio scales abound in psychology, they miss the opportunity to deliver specific evidence for their existence. Michell (2019), on the other hand, misconstrues my objection against the practical usefulness of conjoint measurement (Trendler, 2019). Furthermore, he underestimates the critical role humans play as measurement instruments—that is, as detectors of magnitudes of psychological attributes as derived quantities—and he also misunderstands the meaning of the Millean Quantity Objection. Finally, in answer to Krantz and Wallsten, I specify my position with regard to the connection between scientific stagnation, measurability, and reproducibility.

Applications of the reflective practice questionnaire in medical education

BACKGROUND

We sought to determine whether the Reflective Practice Questionnaire (RPQ) is a reliable measure of reflective capacity and related characteristics in medical students. We also planned to learn how the RPQ could be used in medical education.

METHODS

The RPQ is a 40 item self-report questionnaire that includes a multi-faceted approach to measuring reflective capacity. It also includes sub-scales on several other theoretically relevant constructs such as desire for improvement, confidence, stress, and job satisfaction. The reliabilities of reflective capacity and other sub-scales were determined by calculating their Cronbach alpha reliability values. In the present study, the RPQ was answered by 98 graduating fourth-year medical students from an American University, and these RPQ scores were compared with general public and mental health practitioner samples from a prior study using ANOVA and Bonferroni adjusted comparisons.

RESULTS

Medical students reported a higher reflective capacity than the general public sample, but students were statistically indistinguishable from the mental health practitioner sample. For medical students, reflective capacity was associated with features of confidence, stress, and desire for improvement. Job satisfaction was positively associated with confidence in communication with patients, and negatively associated with stress when interacting with patients. A cluster analysis revealed that around 19% of the medical students exhibited a relatively high level of anxiety interacting with patients, 23% were less engaged, 5% were dissatisfied, and 7% expressed a level of over-confidence in their knowledge and skills that was concerning.

CONCLUSIONS

The RPQ is a reliable measure of reflective capacity (Chronbach's alpha value = 0.84) and related characteristics (Cronbach's alpha values from 0.75 to 0.83) in medical students. The RPQ can be used as part of pre-post evaluations of medical education initiatives, to complement student self-reflection activities in the curriculum, and to identify students who might benefit from targeted intervention.

Statistics for Evaluating Pre-post Change: Relation Between Change in the Distribution Center and Change in the Individual Scores

In a number of scientific fields, researchers need to assess whether a variable has changed between two time points. Average-based change statistics (ABC) such as Cohen's d or Hays' ω² evaluate the change in the distributions' center, whereas Individual-based change statistics (IBC) such as the Standardized Individual Difference or the Reliable Change Index evaluate whether each case in the sample experienced a reliable change. Through an extensive simulation study we show that, contrary to what previous studies have speculated, ABC and IBC statistics are closely related. The relation can be assumed to be linear, and was found regardless of sample size, pre-post correlation, and shape of the scores' distribution, both in single group designs and in experimental designs with a control group. We encourage other researchers to use IBC statistics to evaluate their effect sizes because: (a) they allow the identification of cases that changed reliably; (b) they facilitate the interpretation and communication of results; and (c) they provide a straightforward evaluation of the magnitude of empirical effects while avoiding the problems of arbitrary general cutoffs.

Impact of Physical and Cognitive Exertion on Cognitive Control

In a recent study, the differential effects of prolonged physiologically challenging exercise upon two executive processes (cognitive control and working memory) were investigated. However, the impact of exercise on the selective inhibition task employed was debatable and needed further analysis to dissociate the effects induced by exercise intensity from those induced by the time spent on task upon cognitive control outcomes. In this study, we propose a thorough analysis of these data, using a generalized mixed model on a trial-by-trial basis and a new measure of the strength of the automatic response based on reaction time distribution, to disentangle the effect of physical fatigue from cognitive fatigue. Despite the prolonged duration of exercise, no decline in cognitive performance was found in response to physical fatigue. The only change observed during 60-min exercise was an acceleration of the correct trials and an increase of errors for incompatible trials. This pattern, shown during low and physiologically challenging exercise, supports the occurrence of cognitive fatigue induced by the repetition of the cognitive tasks over time.

The influence of a hurdle target point on the kinematics of the handspring vault approach run during training

The aim of this study was to investigate if a visible target for the hurdle take-off would influence the onset of visual regulation and hurdle kinematics during the approach run. Ten elite male gymnasts (age 23.4 ± 4.9 years, height 1.68 ± 0.06 m, mass 63.3 ± 6.2 kg) performed six handspring vaults with a full approach run under two controlled conditions: (a) with a 5-cm white tape on the runway marking the last touchdown of the approach run and the commencement of the hurdle (tape condition-T) and (b) under the standard vaulting regulations (non-tape condition-NT). Spatiotemporal data of the approach run and the hurdle were collected by four stationary and one panning cameras (sampling rate 300 fps). Eight out of 10 gymnasts commenced regulation earlier under T than under NT. Under T condition, horizontal velocity (Vx _to = 9.06 ± 0.41 m/s) and vertical velocity (V _to = 9.35 ± 0.37 m/s) was significantly faster than under NT condition (Vx _to = 8.85 ± 0.49 m/s; V _to = 9.11 ± 0.47 m/s). Introducing a target for the hurdle facilitates an early onset of step regulation and significantly improves the kinematics of the hurdle.

No Evidence Against Sketch Reinstatement of Context, Verbal Labels or the Use of Registered Intermediaries for Children with Autism Spectrum Disorder: Response to Henry et al. (2017)

Recently, Henry et al. (J Autism Dev Disord 8:2348-2362, 2017) found no evidence for the use of Verbal Labels, Sketch Reinstatement of Context and Registered Intermediaries by forensic practitioners when interviewing children with a diagnosis of autism spectrum disorder. We consider their claims, noting the limited ecological validity of the experimental paradigm, the impacts of repeated interviewing where retrieval support is not provided at first retrieval, question the interviewer/intermediary training and their population relevant experience, and comment on the suppression of population variances. We submit that rejecting these techniques on the basis of this study is completely unwarranted and potentially damaging, particularly if used in legal proceedings to undermine the value of testimony from children with ASD, who continually struggle to gain access to justice.

Performing Inferential Statistics Prior to Data Collection

Typically, in education and psychology research, the investigator collects data and subsequently performs descriptive and inferential statistics. For example, a researcher might compute group means and use the null hypothesis significance testing procedure to draw conclusions about the populations from which the groups were drawn. We propose an alternative inferential statistical procedure that is performed prior to data collection rather than afterwards. To use this procedure, the researcher specifies how close she or he desires the group means to be to their corresponding population means and how confident she or he wishes to be that this actually is so. We derive an equation that provides researchers with a way to determine the sample size needed to meet the specifications concerning closeness and confidence, regardless of the number of groups.

Do Our Means of Inquiry Match our Intentions?

A key stage of the scientific method is the analysis of data, yet despite the variety of methods that are available to researchers they are most frequently distilled to a model that focuses on the average relation between variables. Although research questions are frequently conceived with broad inquiry in mind, most regression methods are limited in comprehensively evaluating how observed behaviors are related to each other. Quantile regression is a largely unknown yet well-suited analytic technique similar to traditional regression analysis, but allows for a more systematic approach to understanding complex associations among observed phenomena in the psychological sciences. Data from the National Education Longitudinal Study of 1988/2000 are used to illustrate how quantile regression overcomes the limitations of average associations in linear regression by showing that psychological well-being and sex each differentially relate to reading achievement depending on one’s level of reading achievement.

Sampling Participants' Experience in Laboratory Experiments: Complementary Challenges for More Complete Data Collection

Speelman and McGann’s (2013) examination of the uncritical way in which the mean is often used in psychological research raises questions both about the average’s reliability and its validity. In the present paper, we argue that interrogating the validity of the mean involves, amongst other things, a better understanding of the person’s experiences, the meaning of their actions, at the time that the behavior of interest is carried out. Recently emerging approaches within Psychology and Cognitive Science have argued strongly that experience should play a more central role in our examination of behavioral data, but the relationship between experience and behavior remains very poorly understood. We outline some of the history of the science on this fraught relationship, as well as arguing that contemporary methods for studying experience fall into one of two categories. “Wide” approaches tend to incorporate naturalistic behavior settings, but sacrifice accuracy and reliability in behavioral measurement. “Narrow” approaches maintain controlled measurement of behavior, but involve too specific a sampling of experience, which obscures crucial temporal characteristics. We therefore argue for a novel, mid-range sampling technique, that extends Hurlburt’s descriptive experience sampling, and adapts it for the controlled setting of the laboratory. This controlled descriptive experience sampling may be an appropriate tool to help calibrate both the mean and the meaning of an experimental situation with one another.

Attaining Automaticity in the Visual Numerosity Task is Not Automatic

This experiment is a replication of experiments reported by Lassaline and Logan (1993) using the visual numerosity task. The aim was to replicate the transition from controlled to automatic processing reported by Lassaline and Logan (1993), and to examine the extent to which this result, reported with average group results, can be observed in the results of individuals within a group. The group results in this experiment did replicate those reported by Lassaline and Logan (1993); however, one half of the sample did not attain automaticity with the task, and one-third did not exhibit a transition from controlled to automatic processing. These results raise questions about the pervasiveness of automaticity, and the interpretation of group means when examining cognitive processes.

To transform or not to transform: using generalized linear mixed models to analyse reaction time data

Linear mixed-effect models (LMMs) are being increasingly widely used in psychology to analyse multi-level research designs. This feature allows LMMs to address some of the problems identified by Speelman and McGann (2013) about the use of mean data, because they do not average across individual responses. However, recent guidelines for using LMM to analyse skewed reaction time (RT) data collected in many cognitive psychological studies recommend the application of non-linear transformations to satisfy assumptions of normality. Uncritical adoption of this recommendation has important theoretical implications which can yield misleading conclusions. For example, Balota et al. (2013) showed that analyses of raw RT produced additive effects of word frequency and stimulus quality on word identification, which conflicted with the interactive effects observed in analyses of transformed RT. Generalized linear mixed-effect models (GLMM) provide a solution to this problem by satisfying normality assumptions without the need for transformation. This allows differences between individuals to be properly assessed, using the metric most appropriate to the researcher's theoretical context. We outline the major theoretical decisions involved in specifying a GLMM, and illustrate them by reanalysing Balota et al.'s datasets. We then consider the broader benefits of using GLMM to investigate individual differences.

From means and variances to persons and patterns

A novel approach for conceptualizing and analyzing data from psychological studies is presented and discussed. This approach is centered on model building in an effort to explicate the structures and processes believed to generate a set of observations. These models therefore go beyond the variable-based, path models in use today which are limiting with regard to the types of inferences psychologists can draw from their research. In terms of analysis, the newer approach replaces traditional aggregate statistics such as means, variances, and covariances with methods of pattern detection and analysis. While these methods are person-centered and do not require parametric assumptions, they are both demanding and rigorous. They also provide psychologists with the information needed to draw the primary inference they often wish to make from their research; namely, the inference to best explanation.