Individual-level Differences Research Articles

Corrigendum: School (socie)ties: individual and school level differences in the association between ethnic/racial victimization and academic functioning

Corrigendum: School (socie)ties: individual and school level differences in the association between ethnic/racial victimization and academic functioning

Association between personal attenuation rating with types of earplugs and noise exposure levels in a textile factory in China

Objective To investigate the effects of earplug type and noise exposure level on textile workers' personal attenuation rating (PAR). Design Initial and follow-up visits were conducted at a 17-month interval. At each visit, a baseline HPD fit test was performed using either a 3M foam or pre-molded earplug, as chosen by the workers. Workers who failed to meet targeted levels were trained and retested. Once they failed again, the other earplug was selected, and training was provided until they achieved the PAR target. Study sample 192 textile workers into three noise exposure level groups (low, medium, high). Results The median baseline PAR was 10 dB at the initial visits and 13 dB at the follow-up visits, and obtained by foam earplug users was 20 dB, which was higher than that obtained by pre-molded earplug users [12 dB (95% CI, 10–15 dB)]. The highest median baseline PAR was obtained by the high noise level group, followed by the median and low noise level groups. Training significantly increased the PAR. Conclusions Multiple types of earplugs need to be offered to workers to deal with individual differences in attenuation, preferences, and exposure levels. Training and stricter compliance policies can improve HPD use and fitting, contributing to better hearing health.

Exploring the Impact of Fasting and Fasting-Mimicking Diets on Type 2 Diabetes Management in Adults: A Systematic Review.

Type 2 diabetes poses significant global health challenges, affecting both the quality of life and healthcare systems. This systematic review evaluates the efficacy of fasting and fasting-mimicking diets (FMD) in managing type 2 diabetes, with a focus on their effects on glycemic control, lipid profiles, and overall metabolic health in adult patients. A comprehensive search of PubMed and Cochrane Library databases identified several studies utilizing various fasting protocols, including intermittent fasting and FMD. Data synthesis and bias assessment were conducted using established methodologies, including the Cochrane Risk of Bias 2 (RoB 2) tool. The review found that fasting interventions significantly improve glycemic control and reduce body weight, with some protocols notably lowering HbA1c levels (p<0.05), highlighting the strong potential of fasting in diabetes management. However, the results varied, suggesting that individual differences in metabolic responses and adherence levels influence outcomes. In conclusion, while fasting and FMD show promise for improving metabolic health and managing diabetes, more standardized research is needed to understand the underlying mechanisms, optimize protocols, and confirm long-term benefits. Future research should prioritize larger sample sizes and extended follow-up periods to inform comprehensive clinical practice guidelines.

Exploring variability in risk taking with large language models.

What are the sources of individual-level differences in risk taking, and how do they depend on the domain or situation in which the decision is being made? Psychologists currently answer such questions with psychometric methods, which analyze correlations across participant responses in survey data sets. In this article, we analyze the preferences that give rise to these correlations. Our approach uses (a) large language models (LLMs) to quantify everyday risky behaviors in terms of the attributes or reasons that may describe those behaviors, and (b) decision models to map these attributes and reasons onto participant responses. We show that LLM-based decision models can explain observed correlations between behaviors in terms of the reasons different behaviors elicit and explain observed correlations between individuals in terms of the weights different individuals place on reasons, thereby providing a decision theoretic foundation for psychometric findings. Since LLMs can generate quantitative representations for nearly any naturalistic decision, they can be used to make accurate out-of-sample predictions for hundreds of everyday behaviors, predict the reasons why people may or may not want to engage in these behaviors, and interpret these reasons in terms of core psychological constructs. Our approach has important theoretical and practical implications for the study of heterogeneity in everyday behavior. (PsycInfo Database Record (c) 2024 APA, all rights reserved).

Infants' salivary oxytocin and positive affective reactions to people

Oxytocin is a neuropeptide positively associated with prosociality in adults. Here, we studied whether infants' salivary oxytocin can be reliably measured, is developmentally stable, and is linked to social behavior. We longitudinally collected saliva from 62 U.S. infants (44 % female, 56 % Hispanic/Latino, 24 % Black, 18 % non-Hispanic White, 11 % multiracial) at 4, 8, and 14 months of age and offline-video-coded the valence of their facial affect in response to a video of a smiling woman. We also captured infants' affective reactions in terms of excitement/joyfulness during a live, structured interaction with a singing woman in the Early Social Communication Scales at 14 months. We detected stable individual differences in infants' oxytocin levels over time (over minutes and months) and in infants' positive affect over months and across contexts (video-based and in live interactions). We detected no statistically significant changes in oxytocin levels between 4 and 8 months but found an increase from 8 to 14 months. Infants with higher oxytocin levels showed more positive facial affect to a smiling person video at 4 months; however, this association disappeared at 8 months, and reversed at 14 months (i.e., higher oxytocin was associated with less positive facial affect). Infant salivary oxytocin may be a reliable physiological measure of individual differences related to socio-emotional development.

Inflammatory Cytokines in Middle Ear Effusion of Patients With Asthma, Chronic Rhinosinusitis With Nasal Polyps With or Without NSAID Intolerance.

To measure the inflammatory cytokines of middle ear effusion (MEE) in otitis media (OM) associated with asthma and chronic rhinosinusitis with nasal polyps (CRSwNP) with or without nonsteroidal anti-inflammatory drug (NSAID) sensitivity to strengthen our assumption that OM is part of the same inflammatory entity. The potential individual differences between MEE inflammatory cytokines could be used in clinical practice for more individual characterization of the inflammation. Case-control study. Tertiary referral center. Convenience sample of 24 case patients with otitis media with effusion (OME) or chronic otitis media (COM), asthma, and CRSwNP, 14 of whom had NSAID intolerance, and 8 controls with OME but no history of asthma, CRSwNP, or NSAID intolerance. Diagnostic. Inflammatory cytokines including interleukins (IL)-4, IL-5, IL-6, IL-13, and interferon gamma (IFN-γ) in middle ear effusion. The MEE mass fractions of IL-5 ( p = 0.003) and IFN-γ ( p = 0.048) were higher among our case patients with OME/COM than among the controls. For IL-4 and IL-13, the mass fractions were also higher among the case patients than the controls, but this difference was not statistically significant ( p = 0.199 and p = 0.617, respectively). We found no difference between the IL-6 mass fractions of the groups. We found notable heterogeneity in individual patients' cytokine levels. According to our findings, OM, when present, should be considered part of the respiratory inflammatory process associated with asthma and CRSwNP. The individual differences in MEE cytokine levels could be useful as biomarkers.

Effects of testosterone on speech production and perception: Linking hormone levels in males to vocal cues and female voice attractiveness ratings

This study sets out to investigate the potential effect of males’ testosterone level on speech production and speech perception. Regarding speech production, we investigate intra- and inter-individual variation in mean fundamental frequency (fo) and formant frequencies and highlight the potential interacting effect of another hormone, i.e. cortisol. In addition, we investigate the influence of different speech materials on the relationship between testosterone and speech production. Regarding speech perception, we investigate the potential effect of individual differences in males’ testosterone level on ratings of attractiveness of female voices.In the production study, data is gathered from 30 healthy adult males ranging from 19 to 27 years (mean age: 22.4, SD: 2.2) who recorded their voices and provided saliva samples at 9 am, 12 noon and 3 pm on a single day. Speech material consists of sustained vowels, counting, read speech and a free description of pictures. Biological measures comprise speakers’ height, grip strength, and hormone levels (testosterone and cortisol). In the perception study, participants were asked to rate the attractiveness of female voice stimuli (sentence stimulus, same-speaker pairs) that were manipulated in three steps regarding mean fo and formant frequencies.Regarding speech production, our results show that testosterone affected mean fo (but not formants) both within and between speakers. This relationship was weakened in speakers with high cortisol levels and depended on the speech material. Regarding speech perception, we found female stimuli with higher mean fo and formants to be rated as sounding more attractive than stimuli with lower mean fo and formants. Moreover, listeners with low testosterone showed an increased sensitivity to vocal cues of female attractiveness.While our results of the production study support earlier findings of a relationship between testosterone and mean fo in males (which is mediated by cortisol), they also highlight the relevance of the speech material: The effect of testosterone was strongest in sustained vowels, potentially due to a strengthened effect of hormones on physiologically strongly influenced tasks such as sustained vowels in contrast to more free speech tasks such as a picture description. The perception study is the first to show an effect of males’ testosterone level on female attractiveness ratings using voice stimuli.

The Benefits of Acute Exercise for Children's Cognition Are Associated with Trait Anxiety.

Children's anxiety is associated with decreased cognitive performance. One well-established behavioral intervention to transiently improve cognitive performance in children is acute aerobic exercise (AAE). Thus far, however, it is unclear whether the benefits of AAE on cognition vary based on individual differences in children's anxiety level. Therefore, we investigated whether trait anxiety levels mediate the effects of AAE on cognitive outcomes in preadolescent children. Ninety-five preadolescent children (9 to 11 yr, 41 females) underwent two experimental interventions in a random, crossover, and counterbalanced design: an exercise protocol (20 min of walking at 65% to 75% of HRpeak) and a nonexercise control (seated rest). Behavioral indices of cognitive performance (accuracy, reaction times, response time (RT) variability) were assessed before and after each intervention using a modified flanker task. The effects of each intervention on cognitive performance were calculated as pre- to postintervention differences (effect scores). These scores were first correlated with children's personal characteristics: anxiety (STAIC), sex, age, body mass index, intelligence quotient, and aerobic fitness. Significant correlations guided subsequent hierarchical regression models, which specifically tested for associations between the effects scores and anxiety levels while controlling for remaining relevant covariates. Regression analysis revealed that anxiety was a significant predictor of the effects that AAE and rest had on cognitive performance. Specifically, higher anxiety scores were associated with greater exercise-induced cognitive benefits (increased accuracy, decreased RT variability; all P < 0.05) and greater rest-induced cognitive impairments (decreased accuracy, increased RT variability; all P < 0.01). These findings suggest that children reporting higher trait anxiety might experience greater cognitive benefits from a single bout of AAE.

Comparing cadence-based and machine learning based estimates for physical activity intensity classification: The UK Biobank

ObjectivesCadence thresholds have been widely used to categorize physical activity intensity in health-related research. We examined the convergent validity of two cadence-based intensity classification approaches against a machine-learning-based intensity schema in 84,315 participants (≥40 years) with wrist-worn accelerometers. DesignValidity study. MethodsBoth cadence-based methods (one-level cadence, two-level cadence) calculated intensity-specific time based on cadence-thresholds while the two-level cadence identified stepping behaviors first. We used an overlapping plot, mean absolute error, and Spearman's correlation coefficient to examine agreements between the cadence-based and machine-learning methods. We also evaluated agreements between methods based on practically-important-difference (moderate-to-vigorous-physical activity: ±20 min/day, moderate-physical activity: ±15, vigorous-physical activity: ±2.5, light-physical activity: ±30). ResultsThe group-level (median) minutes of moderate-to-vigorous- and moderate-physical activity estimated by one-level cadence were within the range of practically-important-difference compared to the machine-learning method (bias of median: moderate-to-vigorous-physical activity, −3.5, interquartile range [−15.8, 12.2]; moderate-physical activity, −6.0 [−17.2, 4.1]). The group-level vigorous- and light-physical activity minutes derived by two-level cadence were within practically-important-difference range (vigorous-physical activity: −0.9 [−3.1, 0.5]; light-physical activity, −1.3 [−28.2, 28.9]). The individual-level differences between the cadence-based and machine learning methods were high across intensities (e.g., moderate-to-vigorous-physical activity: mean absolute error [one-level cadence: 24.2 min/day; two-level cadence: 26.2]), with the proportion of participants within the practically-important-difference ranging from 8.4 % to 61.6 %. ConclusionsOne-level cadence showed acceptable group-level estimates of moderate-to-vigorous and moderate-physical activity while two-level cadence showed acceptable group-level estimates of vigorous- and light-physical activity. The cadence-based methods might not be appropriate for individual-level intensity-specific time estimation.

An examination of individual differences in levels of processing

ABSTRACT The present study examined individual differences in levels of processing. Participants completed a cued recall task in which they made either rhyme or semantic judgements on pairs of items. Pupillary responses during encoding were recorded as a measure of the allocation of attentional effort and participants completed multiple measures of working and long-term memory. The results suggested levels of processing effect in both accuracy and pupillary responses with deeper levels of processing demonstrating higher accuracy and larger pupillary responses than shallower levels of processing. Most participants demonstrated levels of processing effect, but there was substantial variability in the size of the effect. Variation in levels of processing was positively related to individual differences in long-term memory and the magnitude of the pupillary levels of processing effect, but not working memory. These results suggest that some of the variation in levels of processing is likely due to individual differences in the allocation of attentional effort (particularly to items processed deeply) during encoding.

Salutogenesis intervention improves cardio-cerebrovascular health in at-risk office workers: A quasi-experimental study.

Cardio-cerebrovascular disease is the major cause of work-related deaths. Salutogenesis indicates individual differences in health levels occur owing to differences in the sense of coherence (SOC). A salutogenesis-based intervention may promote cardio-cerebrovascular health at work. This study examined the effects of a SOC promotion program based on salutogenesis. Quasi-experimental study. Fifty-six office workers who were above the "low risk" of cardio-cerebrovascular disease from two workplaces were included in the final analysis. Data collected pre- and postintervention. To determine the intervention's effectiveness, repeated-measures analysis of variance was used. The intervention group was provided with the SOC promotion program, whereas the control group was provided with educational materials alone for 12weeks. Generalized resistance resources (GRRs; knowledge of cardio-cerebrovascular disease prevention, stress-coping strategies, and social support) and SOC significantly improved in the intervention group. The intervention group showed significant improvements in occupational stress, physical activity, dietary behavior, total cholesterol level, fasting glucose level, hemoglobin A1C level, body mass index, waist circumference, diastolic and systolic blood pressure, and cardio-cerebrovascular risk. Systematic salutogenesis-based SOC promotion programs should be established to enhance the cardio-cerebrovascular health of office workers at-risk of cardio-cerebrovascular diseases. Trial Registration Number is KCT0007029. The date of registration is February 23, 2022.

Nudging News Readers: A Mixed-Methods Approach to Understanding When and How Interface Nudges Affect News Selection

Building on research on nudging as well as democratic news recommender design, this preregistered study employed a mixed-methods design to explore how interface nudges and article positioning affect news selection. Specifically, we tested whether a position nudge as well as three different types of interface nudges (e.g., popularity cues and social norm interventions) can facilitate readers’ engagement with current affairs news over other genres. To better understand how users processed and perceived the nudges, we further substantiated the experimental results with qualitative insights from a think-aloud protocol and semi-structured interviews. Our experimental results revealed strong effects of the position nudge, but no significant effects of interface nudges. Exploratory analyses indicated that interface nudges must be noticed to affect news selection, while our qualitative insights point to considerable individual-level differences in how nudges are perceived and evaluated. Thus, our study suggests that effective nudging requires carefully pre-tested design and a nuanced understanding of individual preferences.

MRNA expression levels of cytochrome P450 CYP1A2, CYP3A4, and CYP3A5 in the epidermis: a focus on individual differences among Japanese individuals

Various cytochrome P450 enzymes (CYPs) that contribute to drug metabolism are expressed in the skin. However, variation among individuals in CYP expression profiles is not well-understood. To investigate CYPs related to the metabolism of transdermal preparations in Japan, multiple skin tissue specimens of individuals of Japanese descent were prepared, and the mRNA expression levels of CYP1A2, CYP3A4, and CYP3A5 were measured. Associations between the expression patterns of these CYPs and body mass index (BMI) were also investigated. There were considerable individual differences in epidermal CYP1A2 mRNA expression levels, and CYP1A2 showed a weak positive correlation with CYP3A4 mRNA expression levels. In contrast to previous results for other organs, epidermal CYP3A4 mRNA expression levels showed a weak positive correlation with BMI. CYP3A4 in the epidermis may have been locally enhanced as a defence mechanism against xenobiotics in response to impaired barrier function. These differences in mRNA expression in the skin may affect the transdermal absorption of drugs, such as lidocaine and fentanyl, which are metabolised by multiple overlapping CYPs. Our study provides new insights into drug metabolism in the skin. These results are valuable for predicting drug effects and transdermal drug transfer rates in Japanese patients.

Cognitive flexibility and depression: The moderator roles of humor styles

Humor style, which involves both adaptive and maladaptive forms, refers to the ways people use humor in daily life. Maladaptive humor styles (self-defeating and aggressive) can be risk factors for various mental disorders, including depression and anxiety. In contrast, adaptive humor styles (affiliative and self-enhancing) are perceived as resilience factors and buffer the negative impact of other risk factors. Cognitive flexibility reflects a capacity to come up with alternative interpretations and resolutions to demanding situations while perceiving them as controllable. Although the connection of high cognitive flexibility with low depression levels has been consistently documented, its interaction with trait-like factors received limited attention. The current study aims to explore the moderator role of humor styles in the association of cognitive flexibility with depression. Data were gathered from 436 (320 women) participants aged 18 and 70 (M = 35.4, SD = 9.18) through scales assessing humor styles, cognitive flexibility, and depression. The results revealed that the interaction of affiliative humor style with cognitive flexibility was significantly linked to the individual differences in depression levels, highlighting that affiliative humor is functional if individuals have difficulty approaching problematic situations from different angles. However, a similar pattern was not observed for other humor styles.

Political Self-Confidence and Affective Polarization.

Even among those who share the same partisan commitments, some people say they despise the opposing party while others report far less animosity. Why are some people more likely to express hostility toward the opposing political party? We explore how individual-level differences in feelings of self-confidence fuel out-party animosities. Drawing on responses to a module of the 2020 Cooperative Election Study, we show that higher levels of internal political efficacy are associated with greater affective polarization. Those who feel self-assured about their political abilities are more likely to admit severing social ties with those who disagree with them and are more tolerant of discrimination against partisan opponents. In a survey experiment, we confirm that those with greater internal efficacy are also more likely to accept discrimination against a member of the opposing party. Affective polarization is greatest among those who feel the most confident of their ability to influence politics.

A network analysis of mechanisms of change during exposures over the course of intensive OCD treatment

Exposure and response prevention (ERP) is an evidence-based treatment for obsessive-compulsive disorder (OCD). Theories for how it works vary in their emphasis on active mechanisms of change. The current study aimed to clarify mechanisms of change in ERP for OCD using network analysis, comparing ERP networks at the start and end of intensive treatment (partial hospital and residential). In our sample of 182 patients, the most central node in both networks was engagement with exposure, which was consistently related to greater understanding of ERP rationale, higher willingness, and less ritualization, accounting for all other variables in the network. There were no significant differences in networks between the start and end of treatment. These results suggest that nonspecific parameters like facilitating engagement in exposures without ritualizing and providing a clear rationale to clients may be key to effective treatment. As such, it may be useful for clinicians to spend adequate time underscoring the need to eliminate rituals to fully engage in exposure tasks and explaining the rationale for ERP prior to doing exposures, regardless of theoretical orientation. Nonetheless, findings represent group-level statistics and more fine-grained idiographic analyses may reveal individual-level differences with respect to central mechanisms of change. Other limitations include demographic homogeneity of our sample.

Short-term personality development and early career success: Two longitudinal studies during the post-graduation transition.

Investigate short-term personality development during the post-graduation transition. Prior research indicates that long-term personality development matters for employment outcomes. However, this evidence is primarily limited to multi-year longitudinal studies. This research switches the focus to personality changes during a shorter, impactful life transition. We examined how short-term personality development during the 14-month post-graduation transition relates to early career outcomes among two diverse samples of graduates from universities (N = 816) and community colleges (N = 567). We used latent growth curve models to examine associations between career outcomes measured 14 months after graduation with initial personality levels and personality changes. Results revealed that mean-level changes in personality were small and mostly negative. Moreover, individual differences in personality changes were not associated with career outcomes. However, initial levels of conscientiousness, emotional stability, and extraversion positively related to both subjective and objective career success. Initial levels of agreeableness were also positively related to subjective (but not objective) success. Findings indicate that individual differences in personality trait levels at graduation are stronger predictors of early career success compared to short-term personality changes during the post-graduation transition. Taken together, these results help define the time sequence through which personality changes relate to career outcomes.

Correcting missingness in passively-generated mobile data with Multi-Task Gaussian Processes

The prevalence of mobile devices and the ubiquity of network connectivity have generated a massive amount of temporally- and spatially-stamped data. A key characteristic of this mobile data is the prevalence of sparsity—for every recorded user, there is a significant amount of missing data. Sparsity leads to bias in the inferred mobility patterns and thus, correcting bias by imputing the missing data potentially creates opportunities for directly using the corrected mobile trajectory data for large-scale simulations in various applications. We propose a multi-task Gaussian process regression model to correct missingness in mobile data. Gaussian processes (GPs) allow for flexible modeling of diverse (i.e., non-linear, locally periodic) data patterns and quantify prediction uncertainty in an interpretable manner. We develop a methodological framework for applying GPs to mobile data. In doing so, we consider the correlations between users’ coordinates (latitudes and longitudes) through multi-task learning and adjust for individual-level differences in data characteristics through parameter initialization and optimization. We introduce and demonstrate the use of smooth (i.e., rational quadratic) and periodic kernels in modeling human mobility data. Relatedly, we analyze our model’s parameters and imputation accuracy with respect to different types of trips (e.g. slower vs faster trips). We also demonstrate our model’s performance in two experiments with real app-based data, in which it outperforms alternative imputation methods. Our implementation is open-source at https://github.com/ekinugurel/GPSImpute.

Using computational models to study accent adaptation: A tutorial

One of the limitations in accent perception research is the difficulty of quantifying how much exposure is needed to observe adaptation to a novel accent. While numerous studies have investigated this issue (Baese-Berk et al., 2013; Clarke &amp; Garrett, 2004), it has been impossible to control for individual-level differences and solely focus on linguistic differences with human participants. However, computational models can be intentionally set in terms of these features to better understand the process of adaptation to novel accents. Here we discuss how machine learning models can be implemented using PyTorch, a framework in Python made by Meta. PyTorch allows for the easy creation of language learning models that can be used in speech-recognition experiments (Paszke et al., 2019). Here we use the Wav2Vec2 model created by Meta, pre-trained on 960 hours of the Librispeech ASR corpus (Panayotov et al., 2015). We discuss importing the model and fine-tuning it using samples of different accents. Next, we demonstrate building a decoder using a greedy algorithm to transform the model's classification into a transcript. Our goal is to compare simulations against data from human participants and tease apart the direct effects of individual variability on accent perception.

Immuno-Enhancing Effects of Galium aparine L. in Cyclophosphamide-Induced Immunosuppressed Animal Models.

This study investigates the immunomodulatory potential of Galium aparine L. (GAE) in immunodeficient animals. In this study, animals were categorized into five groups: the normal group, CYP group (cyclophosphamide intraperitoneal injection), GA5 group (cyclophosphamide + 5 μg GAE), GA50 group (cyclophosphamide + 50 μg GAE), and GA500 group (cyclophosphamide + 500 μg GAE). The CYP group exhibited significantly reduced spleen weights compared to the normal group, while the groups obtaining GAE displayed a dose-dependent increase in spleen weight. Furthermore, the GAE demonstrated dose-dependent enhancement of splenocyte proliferating activity, with significant increases observed in both LPS and ConA-induced assays. NK cell activity significantly increased in the GA50 and GA500 groups compared to the CYP group. Cytokine analysis revealed a significant increase in IL-6, TNF-α, and IFN-γ levels in ConA-induced splenocytes treated with GAE. Gene expression analysis identified 2434 DEG genes in the extract groups. Notable genes, such as Entpd1, Pgf, Thdb, Syt7, Sqor, and Rsc1al, displayed substantial differences in individual gene expression levels, suggesting their potential as target genes for immune enhancement. In conclusion, Galium aparine L. extract exhibits immunomodulatory properties. The observed gene expression changes further support the potential of Galium aparine L. extract as a natural agent for immune augmentation.