Neurobiology of the structure of personality: dopamine, facilitation of incentive motivation, and extraversion

Adolescent extraversion and agreeableness predict adult alcohol use: A 22-Year prospective study

The Five Factor Model (FFM or Big 5) traits of extraversion, agreeableness, conscientiousness, neuroticism and openness, have all been associated with alcohol use. However, the vast majority of these studies have used cross-sectional designs, limiting the ability to evaluate the temporal relationships between childhood personality traits in adult alcohol use patterns. In the current prospective community cohort study (N = 329), we examine the predictive value of FFM traits measured in childhood and adolescence (starting at 6-9 years of age; well before the typical age at which adolescents begin drinking) for alcohol use in adulthood (27-30 years of age), spanning an average of 22 years. Personality was assessed with the Hierarchical Personality Inventory for Children (HiPIC) across 5 consecutive waves utilizing multiple informants (child, mother, father, and teachers). Alcohol use was measured by the self-report Quantity-Frequency Variability Index (QFV). A series of regression analyses indicates that during adolescence, high levels of extraversion and low levels of agreeableness are both (independently) associated with heavier drinking. These associations are robust and consistent from the first adolescent wave (age 12-15 years) to the last adolescent wave. Notably, informant-dependent measures from early childhood waves (ages 6-9) were not significant predictors, highlighting the importance of considering developmental context and informant variability. By leveraging a longitudinal design with temporally separated measures of personality and alcohol use, this study minimizes concerns about reverse causality. The results highlight the long-term relevance of adolescent personality traits in understanding adult drinking behavior and suggest that targeted prevention strategies focusing on highly extraverted and low-agreeable adolescents may help reduce harmful drinking patterns later in life.

Self-reported history of head injury is associated with cognitive impulsivity on a delay discounting task

Background

Head injuries are a major health care concern that can produce many long lasting cognitive, mental, and physical problems. An emerging literature indicates increased impulsivity in patients with a history of traumatic brain injury (TBI). In a recent study, Veterans with clinically-assessed history of mild TBI had increased cognitive, but not motor, impulsivity. Cognitive impulsivity refers to a preference for smaller immediate rewards (i.e., less willing to wait for larger rewards) while motor impulsivity refers to difficulty inhibiting a motor response. This study extended this work to investigating cognitive and motor impulsivity in a non-clinical sample of putatively healthy undergraduates self-reporting a history of head injury.

Methods

One hundred and sixteen undergraduates, fifty reporting a history of head injury (HI+) and sixty-six reporting no head injury (HI-), participated in an online study via Qualtrics. They completed a series of demographic questionnaires, the UPPS Impulsive Behavior Scale, a computer-based Go/No-go task to assess motor impulsivity, and a computer-based version of the Monetary Choice Questionnaire (MCQ) to assess cognitive impulsivity.

Results

HI+ individuals exhibited cognitive impulsivity, measured as a reduced willingness to wait for a larger delayed reward in the MCQ, as compared to HI- individuals. There were no significant differences in performance on the Go/No-go task between the HI+ and HI- groups. Overall, these findings that a self-reported history of head injury in a non-clinical sample are related to cognitive impulsivity, but not motor impulsivity, are consistent with findings from Veterans with clinically-assessed mild TBI. Future work should assess more details on head injuries to further explore how a head injury relates to cognitive impulsivity.

Extraversion and the Brain: A Coordinate-Based Meta-Analysis of Functional Brain Imaging Studies on Positive Affect

OBJECTIVE

Extraversion is a fundamental personality dimension that contributes to an individual's overall health and well-being. Many studies have examined the neural bases of extraversion but these results are inconsistent. This study adopted a meta-analysis approach to examine the brain activity correlates of extraversion by incorporating functional neuroimaging studies in the context of positive affect/emotional stimuli.

METHODS

A systematic literature search was performed in the databases of PubMed, Web of Science Core Collection, Embase, PsycInfo, CNKI, WanFang, and Weipu. The demographic characteristics and basic information of the included studies were first summarized. Then, a meta-analysis was conducted using anisotropic effect-size seed-based d mapping. Jackknife sensitivity analysis was next conducted to examine the reliability of the findings. Finally, meta-regression analysis was performed to test the potential demographic effects (i.e., sex and age) on the association between extraversion and brain activity.

RESULTS

A total of 11 studies were included in the meta-analysis. The results of meta-analysis revealed robust and consistent positive correlations between extraversion and activation of right inferior frontal gyrus/insula, right angular gyrus, and left precentral gyrus during positive affect processing. In contrast, brain activity in the right striatum during positive affect processing was negatively associated with extraversion. Additionally, meta-regression analysis revealed sex as a moderator in the relationship between extraversion and right insular activation.

CONCLUSIONS

Overall, our study is the first to provide a comprehensive understanding of functional brain activation patterns of extraversion, which may be helpful for targeting of specific brain regions in personalized interventions for extraversion-related psychological/physical illness.

Appetitive and Aversive Motivation in Dysregulated Behaviors: A Meta-Analysis

Appetitive and aversive motivation are prominent in theories of dysregulated behaviors. The authors conducted a meta-analysis of the association between individual differences in appetitive and aversive motivation and several dysregulated behaviors (i.e., alcohol use, marijuana use, tobacco use, binge eating, aggression, gambling, and nonsuicidal self-injury). Alcohol use (r = .17, k = 141), marijuana use (r = .13, k = 23), aggression (r = .22, k = 52), and gambling (r = .08, k = 55) were all significantly positively related to appetitive motivation. Binge eating (r = .28, k = 34) and self-injury (r = .17, k = 10) were significantly positively related to aversive motivation. Effect sizes were similar to the median effect size in personality research. Together, these results provide some evidence that some dysregulated behaviors are more correlated with approach motivation, whereas others are more correlated with aversive motivation, which may indicate distinct etiological pathways.

Behavioral Inhibition and Fear: The Moderating Role of Emotional Competence and Gender in Preadolescents

BACKGROUND

The behavioral inhibition system (BIS) is a key motivational system that shapes human emotions and behaviors; specifically, the BIS regulates avoidance behaviors, and it is linked to negative emotions such as fear and anxiety. Previous studies have demonstrated a link between high BIS scores and attentional bias to threat in children, but literature is inconsistent. This may be due to differences in the individual awareness of emotions or in the accuracy of effectively detecting emotions. Moreover, the past literature has also found gender differences in BIS scores, which may suggest differential processes in boys and girls.

METHODS

The present study aims to investigate whether BIS scores were associated with an attentional facilitation index of fear in a sample of preadolescents (n = 264; 52.27% girls; M age = 12.98 years; SD = 0.89 years), considering the potential moderating role of (a) the awareness of others' emotions as assessed by a self-report questionnaire, (b) emotion perception accuracy of fear as assessed by a laboratory task of emotion recognition, and (c) gender.

RESULTS

Our results showed that, only in males, higher scores of the BIS were associated with a lower attentional facilitation index of fear in the conditions of low levels of emotional competence (i.e., low levels of self-reported awareness of other emotions or low levels of accuracy recognition of fearful faces).

CONCLUSIONS

Results were discussed in light of both theories of emotional development and practical clinical implications, with special attention to the emerged gender difference.

The bioSocial Cognitive Theory of eating (bSCT-e): Applying and elaborating on a biopsychosocial substance use theory for food addiction

Obesity rates are increasing globally, and food addiction (FA1) may be an important contributing factor but there is a lack of understanding of the key psychological mechanisms that contribute to FA. The bioSocial Cognitive Theory (bSCT) proposes that substance use is predicted by biologically based personality traits and their influence on social cognitive mechanisms. While validated in substance use, bSCT has not been applied to a behavioural or non-substance addiction. However, the bSCT does not include a negative affective personality component, of which there is clear theoretical and empirical support as risk factors for FA. Thus, this study sought to test both the original bSCT model and an elaborated version related to eating (bSCT-e) that included direct and indirect punishment sensitivity pathways to identify the individual risk factors of FA. Data were collected from 204 university students (75.5% female; Mage = 24.82, SD = 9.17) via an online survey. Both original bSCT and bSCT-e models provided a good fit to the data, with the latter providing slightly better fit and accounting for more variance in FA. The findings suggest that individuals who are more reward driven and punishment sensitive hold exaggerated beliefs about the reinforcing and emotion regulation effects of eating, which may undermine eating control and increase risk of FA. This study provides potential new insights into the complex biopsychosocial mechanisms of FA, and points to potential intervention targets.

Do inflammation and relational motivation coordinate having better sex? The interplay between C-reactive protein and relational approach motivation on sexual well-being

Much evidence on heightened inflammation and social behavior focuses on social withdrawal. Building on recent theory (Muscatell and Inagaki, 2021), we focused instead on the socially affiliative experience of sex. We investigated the interplay between immunology and motivation on sexual well-being among 158 individuals in romantic relationships. Inflammation, indexed by C-reactive protein (CRP), and sexual well-being were measured multiple times over a month. Relational approach motivation (i.e., motivation toward rewards in relationships) was measured at study entry. Results revealed significant associations between CRP and sexual satisfaction and partnered orgasms frequency for those most motivated to approach rewards with their partner. Interaction effects were replicated with relationship-focused psychological correlates of sexual well-being (e.g., touch, shared laughter, social support), but not with individual-focused outcomes (e.g., adapting to change, goal progress). This is one of the first human studies to demonstrate the body and mind coordinate to promote satisfying sexual experiences within romantic relationships.

Early Salience Signals Predict Interindividual Asymmetry in Decision Accuracy Across Rewarding and Punishing Contexts

Asymmetry in choice patterns across rewarding and punishing contexts has long been observed in behavioural economics. Within existing theories of reinforcement learning, the mechanistic account of these behavioural differences is still debated. We propose that motivational salience-the degree of bottom-up attention attracted by a stimulus with relation to motivational goals-offers a potential mechanism to modulate stimulus value updating and decision policy. In a probabilistic reversal learning task, we identified post-feedback signals from EEG and pupillometry that captured differential activity with respect to rewarding and punishing contexts. We show that the degree of between-context distinction in these signals predicts interindividual asymmetries in decision accuracy. Finally, we contextualise these effects in relation to the neural pathways that are currently centred in theories of reward and punishment learning, demonstrating how the motivational salience network could plausibly fit into a range of existing frameworks.

Evaluating the effect of an individualised reward-related impulsivity induction on ad libitum alcohol consumption: A pilot study

Impulsivity has well-documented associations with risky alcohol use. Little evidence exists on the causal mechanisms, but emerging experimental evidence suggests a role for reward-related impulsivity. Recent work experimentally increased reward-related impulsivity to increase drinking using standardised reward-cue stimuli. The present study piloted participant-generated reward-cue stimuli to increase laboratory alcohol consumption. Sixteen participants (56.3 % male; M age = 20.13, SD = 1.78) attended two laboratory sessions (experimental and control). In the experimental session, the Individualised Reward-seeking Induction Schedule (IRIS) had participants re-experience an intense, vivid memory of an approach motivational state (control session: no induction) before completing a laboratory drinking task. Self-reported reward-seeking, positive, and negative affect were measured. IRIS significantly increased alcohol consumption by 53.65 ml (SE = 29.11, p <.001) when controlling for positive and negative affect. IRIS also produced significantly higher state reward-seeking (Δꭓ2 (1) = 14.02, p <.001). Findings provide preliminary validation of IRIS, a new experimental methodology to investigate impulsivity-related alcohol use. Replication of observed effects in a larger sample is required. The present study supports the use of IRIS in future research to understand the causal role of reward-related impulsivity on alcohol consumption.

Out with the bad, in with the good: A review on augmented extinction learning in humans

Several leading therapies for anxiety-related disorders rely on the principles of extinction learning. However, despite decades of development and research, many of these treatments remain only moderately effective. Developing techniques to improve extinction learning is an important step towards developing improved and mechanistically-informed exposure-based therapies. In this review, we highlight human research on strategies that might augment extinction learning through reward neurocircuitry and dopaminergic pathways, with an emphasis on counterconditioning and other behaviorally-augmented forms of extinction learning (e.g., novelty-facilitated extinction, positive affect training). We also highlight emerging pharmacological and non-pharmacological methods of augmenting extinction, including L-DOPA and aerobic exercise. Finally, we discuss future directions for augmented extinction learning and memory research, including the need for more work examining the influence of individual differences and psychopathology.

Serotonin release by parachloroamphetamine in rats with high and low sociability: High prefrontal release capacity in sociable females

BACKGROUND

Social behaviour is the expression of one of the most generally accepted independent dimensions of personality. Serotonergic neurotransmission has been implicated in typical social response and drugs that promote serotonin (5-hydroxytryptamine (5-HT)) release have prosocial effects. By using the social interaction test, we have previously demonstrated sociability as a temperamental trait in male Wistar rats.

AIMS

To assess sociability in male rats of the Sprague-Dawley strain and in female rats of both Wistar and Sprague-Dawley strain, and extracellular levels of 5-HT in rats with high and low sociability (high sociability (HS)- and low sociability (LS)-rats).

METHODS

Social interaction test conducted with different weight-matched partners was used to assess sociability, and in vivo, microdialysis was performed before and after administration of a low dose (2 mg/kg) of parachloroamphetamine (PCA) in the prefrontal cortex, dorsamedial striatum and ventral tegmental area.

RESULTS

Similarly to male Wistar rats, female Wistars and Sprague-Dawley rats of both sexes displayed trait-wise sociability. Male Wistar HS-rats had lower extracellular levels of 5-HT in prefrontal cortex at baseline and after administration of PCA, and higher PCA-induced increase of extracellular 5-HT in ventral tegmental area. In dorsomedial striatum, PCA elicited a comparable increase in extracellular dopamine in HS- and LS-rats, but higher release of 5-HT in HS-rats. Comparison of PCA-induced 5-HT release in prefrontal cortex of male and female Sprague-Dawley rats revealed a larger 5-HT response in female HS-rats.

CONCLUSIONS

5-HT release potential is higher in rats with high expression of sociability trait, whereas some regionally variable differences may be related to relative contributions of social motivation and anxiety in shaping social behaviour.

Validation of the German long and short versions of the UPPS-P Impulsive Behavior Scale

OBJECTIVE

The UPPS-P Impulsive Behavior Scale is a widely used self-report measure of impulsivity, but there is currently no validated German version that includes the Positive Urgency scale.

METHODS

We combined existing German translations of UPPS scales and included the Positive Urgency dimension to validate the UPPS-P in a sample of 399 participants. In addition, we developed a revised short version of the UPPS-P (SUPPS-P) with 20 items and conducted a confirmatory factor analysis (CFA) to verify the structure in an independent validation sample with 349 participants. To determine evidence of convergent and discriminant validity, we used measures of impulsivity, depression, anxiety, stress, problematic alcohol and substance use.

RESULTS

CFA of the five factorial structure of the UPPS-P demonstrated acceptable fits and evidence of validity and reliability for the subscales. Psychometric characteristics of the SUPPS-P using the original item configuration were not satisfactory. As a result, we developed a revised German version of the SUPPS-P and confirmed the five-factor structure using a CFA in the validation sample. For the revised version, model fits and evidence of validity and internal consistencies were good. Associations with other constructs were as expected. For example, whereas Sensation Seeking was associated moderately with problematic alcohol use, lacking associations of Lack of Premeditation to internalizing symptoms showed evidence of discriminant validity.

DISCUSSION

The German translations of both UPPS-P and SUPPS-P are valid tools for measuring impulsive behaviors. They are well-suited for exploring the associations between different facets of impulsivity and psychopathological phenomena.

Personality and COMT gene: molecular-genetic and epigenetic associations with NEO-PI-R personality domains and facets in monozygotic twins

Background

This study investigates the relationship between MB-COMT DNA methylation (DNAm) and the personality traits outlined in the NEO-PI-R model through an epigenetic study of monozygotic twins. DNAm, a critical epigenetic mechanism, regulates gene expression and has been linked to various biological processes and disorders. By leveraging the genetic similarities of monozygotic twins, this research explores how epigenetic variations influenced by environmental factors correlate with personality differences.

Methods

The study utilized the Five-Factor Model (FFM) to categorize personality traits into five domains: Neuroticism, Extraversion, Conscientiousness, Agreeableness, and Openness to Experience. Each domain comprises six facets, providing a granular view of personality. The research centered on the catechol-O-methyltransferase (COMT) gene, focusing on its role in dopamine metabolism, which is hypothesized to influence personality traits through the dopaminergic system. DNAm status in the MB-COMT promoter region was examined to determine its association with personality facets.

Results

Preliminary findings suggest a complex interaction between MB-COMT DNAm patterns and personality traits. Specific methylation patterns at different CpG sites were linked to varying expressions of traits such as impulsivity and aggression, highlighting the nuanced impact of epigenetics on personality.

Conclusion

This study underscores the potential of integrating genetic, epigenetic, and environmental data to enhance our understanding of personality formation. The results contribute to a broader understanding of how genetic predispositions shaped by environmental factors manifest in complex trait differences, paving the way for future research in genetic psychiatry and personalized medicine.

Social Homeostasis and Psychoactive Drugs: What Can We Learn From Opioid and Amphetamine Drug Challenge Studies in Humans?

Social disequilibrium, or disrupted social homeostasis, underlies many behavioral disorders, including problematic drug use. One way to study the relationship between drug use and social homeostasis is to determine whether single doses of psychoactive drugs relieve some of the discomfort of social isolation and promote social connection. In this narrative review, we discuss challenges and opportunities in studying the relationship between psychoactive drugs and social homeostasis. Using the examples of opioids and amphetamines, we discuss the evidence that drugs alleviate dysphoria related to lack of social connection or produce prosocial effects that improve connection. With regard to opioid drugs, we report that mu opioid agonists and kappa opioid antagonists reduce distress from social isolation, and mu opioid agonists enhance social reward. Amphetamine-like stimulant drugs, including MDMA, do not seem to act by reducing the distress of social isolation, but they have notable prosocial effects that increase both motivation for social contact and the pleasure derived from interacting socially. Many questions remain in understanding interactions between drugs and social equilibrium, including whether these effects contribute to problematic drug use. We identify gaps in knowledge, including the effects of drug withdrawal or dependence on social function or the responses of individuals with psychiatric symptomatology. Understanding these actions on social processes will help to develop novel pharmacological treatments for clinical problems related to social disequilibrium.

Does personality affect the cognitive decline in aging? A systematic review

Cognitive decline is a natural consequence of aging, but several genetic, environmental, and psychological factors can influence its trajectories. Among the most enduring factors, the Big Five personality traits - defined as relatively stable tendencies to think, behave, and react to the environment - can influence both directly (e.g., by physiological correlates) and indirectly (e.g., healthy or risky behaviors) the risk of developing dementia and mild cognitive impairment (MCI) - a preclinical form of cognitive decline. Despite the great amount of studies focusing on the relationship between personality and cognitive decline, an updated systematic synthesis of the results including a broader range of study designs is still lacking. This systematic review aims to summarize the findings of studies investigating: (i) differences in personality traits between groups of healthy individuals and those with MCI, (ii) the impact of personality traits on the risk for both MCI and dementia, and (iii) changes in personality traits among individuals progressing from normal cognition to MCI. Neuroticism emerged as a significant risk factor for MCI and dementia; Conscientiousness and Openness appear to offer protection against dementia and moderate cognitive decline. Overall, these findings suggest a pivotal role of personality structure in shaping cognitive outcomes on the long run.

Quantitative evaluation of a theoretical-conceptual model based on affective and socio-behavioral dimensions to explain the academic performance of mathematics students

Objective

There is evidence that suggests that affective dimensions, personality traits, as well as students' cooperative interpersonal interactions, are an important element in the students learning process. In this work we propose a theoretical model, based on evidence, that shows the direct and indirect relationships between these factors and academic performance in mathematics courses, in undergraduate and school students.

Methods

To understand the type of relationships between these variables, the PANAS psychometric test of positive and negative affect, the BIG FIVE personality test and the economic decision game DUPLES GAME were applied. The study sample was 130 students between 17 and 22 years of age from undergraduate and school (M ± SD = 20.1 ± 3.99).

Results

From a path analysis, statistically significant relationships were found, for example, a direct relationship between neuroticism and positive affect, which in turn is related to academic performance. We also found a direct relationship between neuroticism and negative affect, extraversion and positive affect. This allows us to propose that some of the independent variables of the model directly and indirectly influence the academic performance of students in the subject of mathematics.

Conclusion

Positive affect and negative affect directly affect academic performance in mathematics, neuroticism has a direct impact on negative affect and extraversion direct impact on positive affect. Consequently, there are direct and indirect relationships between personality traits and affective dimensions, which affect the academic performance of mathematics students.

Attention control training and transfer effects on cognitive tasks

Attention control is the common element underlying different executive functions. The backward Masking Majority Function Task (MFT-M) requires intensive attention control, and represents a diverse situation where attentional resources need to be allocated dynamically and flexibly to reduce uncertainty. Aiming to train attention control using MFT-M and examine the training transfer effects in various executive functions, we recruited healthy young adults (n = 84) and then equally randomized them into two groups trained with either MFT-M or a sham program for seven consecutive days. Cognitive evaluations were conducted before and after the training, and the electroencephalograph (EEG) signals were recorded for the revised Attention Network Test (ANT-R), N-back, and Task-switching (TS) tasks. Compared to the control group, the training group performed better on the congruent condition of Flanker and the double-congruency condition of Flanker and Location in the ANT-R task, and on the learning trials in the verbal memory test. The training group also showed a larger P2 amplitude decrease and P3 amplitude increase in the 2-back task and a larger P3 amplitude increase in the TS task's repeat condition than the control group, indicating improved neural efficiency in two tasks' attentional processes. Introversion moderated the transfer effects of training, as indicated by the significant group*introversion interactions on the post-training 1-back efficiency and TS switching cost. Our results suggested that attention control training with the MFT-M showed a broad transfer scope, and the transfer effect was influenced by the form of training task. Introversion facilitated the transfer to working memory and hindered the transfer to flexibility.

The Continuing Challenges of Studying Parallel Behaviours in Humans and Animal Models

The use of animal models continues to be essential for carrying out research into clinical phenomena, including addiction. However, the complexity of the clinical condition inevitably means that even the best animal models are inadequate, and this may go some way to account for the apparent failures of discoveries from animal models, including the identification of potential novel therapies, to translate to the clinic. We argue here that it is overambitious and misguided in the first place to attempt to model complex, multifacetted human disorders such as addiction in animals, and especially in rodents, and that all too frequently "validity" of such models is limited to superficial similarities, referred to as "face validity", that reflect quite different underlying phenomena and biological processes from the clinical situation. Instead, a more profitable approach is to identify (a) well-defined intermediate human behavioural phenotypes that reflect defined, limited aspects of, or contributors to, the human clinical disorder, and (b) to develop animal models that are homologous with those discrete human behavioural phenotypes in terms of psychological processes, and underlying neurobiological mechanisms. Examples of past and continuing weaknesses and suggestions for more limited approaches that may allow better homology between the test animal and human condition are made.

Do Narcissist Phubs or Get Phubbed? Analyzing the Role of Motivational Systems

Phubbing is a common sight, but it is not merely a technological faux pas. The present study aims to explore phubbing (phubbing others and getting phubbed) through the lens of two types of personalities (grandiose and vulnerable narcissism). Moreover, the study also aimed to evaluate the indirect role of motivational systems (BAS/BIS) between these two sets of variables. The sample of the study comprised 525 Indian college students. Data were analyzed through Hayes Process Macro (Hayes) in SPSS (Version 26). Vulnerable narcissism was found to be positively related to phubbing others and getting phubbed. Grandiose narcissism was found to be related to phubbing others but not to getting phubbed. BAS and BIS were significantly and positively related to phubbing and getting phubbed. BAS indirectly affected the relationship between two kinds of narcissism (vulnerable and grandiose) and phubbing (phubbing others and getting phubbed); however, BIS failed to influence the relationship between narcissism and phubbing. The results of the present study challenge the notion that all phubbing behaviors are truly deviant as narcissistic personality played an important role in phubbing behavior. The study also highlighted the importance of rewards and punishment on phubbing behaviors, and therefore there is a need to focus on BAS and BIS while dealing with phubbing behaviors.

Disentangling periodic and aperiodic resting EEG correlates of personality

Previous studies of resting electroencephalography (EEG) correlates of personality traits have conflated periodic and aperiodic sources of EEG signals. Because these are associated with different underlying neural dynamics, disentangling them can avoid measurement confounds and clarify findings. In a large sample (n = 300), we investigated how disentangling these activities impacts findings related to two research programs within personality neuroscience. In Study 1 we examined associations between Extraversion and two putative markers of reward sensitivity-Left Frontal Alpha asymmetry (LFA) and Frontal-Posterior Theta (FPT). In Study 2 we used machine learning to predict personality trait scores from resting EEG. In both studies, power within each EEG frequency bin was quantified as both total power and separate contributions of periodic and aperiodic activity. In Study 1, total power LFA and FPT correlated negatively with Extraversion (r ∼ -0.14), but there was no relation when LFA and FPT were derived only from periodic activity. In Study 2, all Big Five traits could be decoded from periodic power (r ∼ 0.20), and Agreeableness could also be decoded from total power and from aperiodic indices. Taken together, these results show how separation of periodic and aperiodic activity in resting EEG may clarify findings in personality neuroscience. Disentangling these signals allows for more reliable findings relating to periodic EEG markers of personality, and highlights novel aperiodic markers to be explored in future research.

Domain-Specific Greed

Greed, the insatiable and excessive desire and striving for more even at the expense of others, may be directed toward various goods. In this article, we propose that greed may be conceptualized as a domain-specific construct. Based on a literature review and an expert survey, we identified 10 domains of greed which we operationalized with the DOmain-SPEcific Greed (DOSPEG) questionnaire. In Study 1 (N = 725), we found support for the proposed structure and convergent validity with related constructs. Bifactor-(S-1) models revealed that generic greed is differentially related to the greed domains, indicating that generic greed primarily captures a striving for money and material things. In the second study (N = 591), we found that greed domains had incremental validity beyond generic greed with regard to corresponding criteria assessed via self- and other-reports. We conclude that greed can be conceptualized as a domain-specific construct and propose an onion model reflecting this structure.

Intrinsic functional connectivity of motor and heteromodal association cortex predicts individual differences in regulatory focus

Regulatory focus theory (RFT) describes two cognitive-motivational systems for goal pursuit-the promotion and prevention systems-important for self-regulation and previously implicated in vulnerability to psychopathology. According to RFT, the promotion system is engaged in attaining ideal goals (e.g. hopes and dreams), whereas the prevention system is associated with accomplishing ought goals (e.g. duties and obligations). Prior task-based functional magnetic resonance imaging (fMRI) studies have mostly explored the mapping of these two systems onto the activity of a priori brain regions supporting motivation and executive control in both healthy and depressed adults. However, complex behavioral processes such as those guided by individual differences in regulatory focus are likely supported by widely distributed patterns of intrinsic functional connectivity. We used data-driven connectome-based predictive modeling to identify patterns of distributed whole-brain intrinsic network connectivity associated with individual differences in promotion and prevention system orientation in 1,307 young university volunteers. Our analyses produced a network model predictive of prevention but not promotion orientation, specifically the subjective experience of successful goal pursuit using prevention strategies. The predictive model of prevention success was highlighted by decreased intrinsic functional connectivity of both heteromodal association cortices in the parietal and limbic networks and the primary motor cortex. We discuss these findings in the context of strategic inaction, which drives individuals with a strong dispositional prevention orientation to inhibit their behavioral tendencies in order to shield the self from potential losses, thus maintaining the safety of the status quo but also leading to trade-offs in goal pursuit success.

Midfrontal conflict theta and parietal P300 are linked to a latent factor of DSM externalising disorders

Psychiatric illnesses form spectra rather than categories, with symptoms varying continuously across individuals, i.e., there is no clear break between health and disorder. Dimensional measures of behaviour and brain activity are promising targets for studying biological mechanisms that are common across disorders. Here, we assessed the extent to which neural measures of the sensitivity of the three biological systems in the reinforcement sensitivity theory (RST) could account for individual differences in a latent general factor estimated from symptom counts across externalising disorders (EXTs). RST explanatory power was pitted against reduced P300, a reliable indicator of externalising per previous research. We assessed 206 participants for DSM-5 EXTs (antisocial personality disorder, conduct disorder, attention-deficit/hyperactivity disorder, intermittent explosive disorder symptoms, alcohol use disorder, and cannabis use disorder). Of the final sample, 49% met diagnostic criteria for at least one of the EXTs. Electroencephalographic measures of the sensitivities of the behavioural activation system (BAS), the fight/flight/freeze system, and the behavioural inhibition system (BIS), as well as P300 were extracted from the gold bar-lemon and stop-signal tasks. As predicted, we found that low neural BIS sensitivity and low P300 were uniquely and negatively associated with our latent factor of externalising. Contrary to prediction, neural BAS/"dopamine" sensitivity was not associated with externalising. Our results provide empirical support for low BIS sensitivity and P300 as neural mechanisms common to disorders within the externalising spectrum; but, given the low N involved, future studies should seek to assess the replicability of our findings and, in particular, the differential involvement of the three RST systems.

Impulse control disorders in Parkinson's disease patients treated with pramipexole and ropinirole: a systematic review and meta-analysis

BACKGROUND

This analysis is the first systematic review and meta-analysis assessing occurrences of ICD in PD patients treated with oral DAs: ropinirole (ROP) and pramipexole (PRX). This study compares the two oral DAs to a transdermal patch, rotigotine (RTG).

METHODS

We performed an extensive systematic search for eligible studies from PubMed, Embase, Cochrane Library, and Google Scholar. The data was analyzed by various software, including EndNote, Rayyan, PRISM, and RevMan. Two studies incorporating 658 patients collectively were assessed.

RESULTS

This meta-analysis shows a significant correlation between the usage of PRX (25.3%) or ROP (21.8%) and the development of ICD in PD patients. Compared to the transdermal patch, RTG, PRX was found to have a significant relative risk (P < 0.0001) of 3.46 (95% CI 2.07-5.76), and ROP was found to have a significant relative risk (P < 0.0001) of 2.98 (95% CI 1.77-5.02). The data collected shows RTG is approximately three times less likely to cause ICDs than oral PRX and ROP.

CONCLUSION

The present investigation provides insight into ICD occurrences with PRX, ROP, and RTG to allow physicians to make more informed decisions on risk versus reward when deciding how to treat a PD patient with these drugs. However, related to various disclosed limitations, our conclusion cannot provide definitive practice protocols.

Resting-state functional network connectivity underlying conscientiousness in school-aged children

Conscientiousness is a personality trait that matures from early childhood to late adolescence, yet little is known about its underlying brain mechanisms during this period. To investigate this, our study examined the resting-state functional network connectivity (rsFNC) of 69 school-aged children (mean age = 10.12 years, range = 9-12) using a whole-brain region-of-interest (ROI) based analysis, based on functional magnetic resonance imaging (fMRI). The results indicated a positive association between conscientiousness and the rsFNC between the fronto-parietal network (FPN) and two brain networks: the somatosensory motor-hand network (SMHN) and the auditory network (AN). However, conscientiousness was negatively associated with the rsFNC between FPN and two other networks: the salience network (SN); the default mode network (DMN). Moreover, our results suggest that the FPN may play a hub role in the neural performance of children's conscientiousness. Intrinsic brain networks, particularly those involved in higher-order cognitive functions, impact children's conscientiousness. Therefore, FPN plays an important role in the development of children's personality, providing insight into the neural mechanisms underlying children's personality.

Understanding Female and Male Insights in Psychology: Who Thinks What?

Evolutionary psychology is the study of human psychological behavior. During childhood, men and women behave similarly; however, as a child approaches puberty, new physical and behavioral changes emerge. Behavioral psychology focuses on understanding the functioning and thought processes of the human mind. The general population lacks knowledge of basic behavioral differences between men and women, leaving them unaware of their role, limitations, societal responsibilities, resulting in an underestimation of their own natural talents and biology. Thus, people tend to follow societal norms rather than exploring and utilizing their natural talents. The current review was designed and conducted to enforce compression on behavioral psychology in both genders as well as to identify variations in hormonal activity and sexual preferences.

Individuals' contribution to household energy savings: The role of big-two personality traits

Household energy consumption (HEC) is one of the major contributors to global emissions, making it a critical area for addressing sustainability challenges. The impact of personality traits on human behaviour is significant in shaping HEC patterns, and therefore, have important implications for sustainability policies. This study aims to investigate role of biologically predicted big-two personality traits (i.e., stability and plasticity), a higher order solution to five-factor traits and orthogonal traits, on HEC. To that end, a structural equation model is developed using a national household survey in Australia. The performance of the model is benchmarked against a five-factor (i.e., agreeableness, consciousness, emotional stability, extraversion and openness) personality trait model. The performance of the models is measured using six goodness-of-fit indices, all of which show a superior performance in the big-two traits model. The results indicate that a higher score in stability poses energy-intensive behaviour, while a higher plasticity score poses energy-saving behaviours. The plasticity trait is linked to environmentally friendly behaviours, while the stability trait is associated with environmentally unfavourable behavioural practices. The effects of socioeconomic status on HEC are mediated by stability and plasticity to identify those who are more likely to change their energy consumption habits as the target group for policy intervention. This study can assist policy makers to determine energy-intensive and energy-saving behaviours from the big-two traits, and to develop more effective and targeted sustainability policies that can help in reducing HEC and promote sustainable living in societies.

Temperament and probabilistic predictive coding in visual-spatial attention

Cholinergic (Ach), Noradrenergic (NE), and Dopaminergic (DA) pathways play an important role in the regulation of spatial attention. The same neurotransmitters are also responsible for inter-individual differences in temperamental traits. Here we explored whether biologically defined temperamental traits determine differences in the ability to orient spatial attention as a function of the probabilistic association between cues and targets. To this aim, we administered the Structure of Temperament Questionnaire (STQ-77) to a sample of 151 participants who also performed a Posner task with central endogenous predictive (80 % valid/20 % invalid) or non-predictive cues (50 % valid/50 % invalid). We found that only participants with high scores in Plasticity and Intellectual Endurance showed a selective abatement of attentional costs with non-predictive cues. In addition, stepwise regression showed that costs in the non-predictive condition were negatively predicted by scores in Plasticity and positively predicted by scores in Probabilistic Thinking. These results show that stable temperamental characteristics play an important role in defining the inter-individual differences in attentional behaviour, especially in the presence of different probabilistic organisations of the sensory environment. These findings emphasize the importance of considering temperamental and personality traits in social and professional environments where the ability to control one's attention is a crucial functional skill.

The interacting partner as the immediate environment: Personality, interpersonal dynamics, and bodily synchronization

OBJECTIVE

In social interactions, humans tend to naturally synchronize their body movements. We investigated interpersonal synchronization in conversations and examined its relationship with personality differences and post-interaction appraisals.

METHOD

In a 15-minute semi-structured conversation, 56 previously-unfamiliar dyads introduced themselves, followed by self-disclosing and argumentative conversations. Their bodily movements were video-recorded in a standardized room (112 young adults, aged 18-33, mean = 20.54, SD = 2.74; 58% Dutch, 31% German, 11% other). Interpersonal bodily synchronization was estimated as (a) synchronization strength using Windowed Lagged Cross-Correlations and (b) Dynamic Organization (Determinism/Entropy/Laminarity/Mean Line) using Cross-Recurrence Quantification Analysis. Bodily synchronization was associated with differences in Agreeableness and Extraversion (IPIP-NEO-120) and post-conversational appraisals (affect/closeness/enjoyment) in mixed-effect models.

RESULTS

Agreeable participants exhibited higher complexity in bodily synchronization dynamics (higher Entropy) than disagreeable individuals, who also reported more negative affect afterward. Interpersonal synchronization was stronger among extroverts than among introverts and extroverts appraised conversations as more positive and enjoyable. Bodily synchronization strength and dynamic organization were related to the type of conversation (self-disclosing/argumentative).

CONCLUSIONS

Interpersonal dynamics were intimately connected to differences in Agreeableness and Extraversion, varied across situations, and these parameters affected how pleasant, close, and enjoyable each conversation felt.

Using rodent data to elucidate dopaminergic mechanisms of ADHD: Implications for human personality

An altered behavioral response to positive reinforcement has been proposed to be a core deficit in attention deficit hyperactivity disorder (ADHD). The spontaneously hypertensive rat (SHR), a congenic animal strain, displays a similarly altered response to reinforcement. The presence of this genetically determined phenotype in a rodent model allows experimental investigation of underlying neural mechanisms. Behaviorally, the SHR displays increased preference for immediate reinforcement, increased sensitivity to individual instances of reinforcement relative to integrated reinforcement history, and a steeper delay of reinforcement gradient compared to other rat strains. The SHR also shows less development of incentive to approach sensory stimuli, or cues, that predict reward after repeated cue-reward pairing. We consider the underlying neural mechanisms for these characteristics. It is well known that midbrain dopamine neurons are initially activated by unexpected reward and gradually transfer their responses to reward-predicting cues. This finding has inspired the dopamine transfer deficit (DTD) hypothesis, which predicts certain behavioral effects that would arise from a deficient transfer of dopamine responses from actual rewards to reward-predicting cues. We argue that the DTD predicts the altered responses to reinforcement seen in the SHR and individuals with ADHD. These altered responses to reinforcement in turn predict core symptoms of ADHD. We also suggest that variations in the degree of dopamine transfer may underlie variations in personality dimensions related to altered reinforcement sensitivity. In doing so, we highlight the value of rodent models to the study of human personality.

Assessment of the relationship between the dopaminergic pathway and severe acute respiratory syndrome coronavirus 2 infection, with related neuropathological features, and potential therapeutic approaches in COVID-19 infection

Dopamine is a known catecholamine neurotransmitter involved in several physiological processes, including motor control, motivation, reward, cognition, and immune function. Dopamine receptors are widely distributed throughout the nervous system and in immune cells. Several viruses, including human immunodeficiency virus and Japanese encephalitis virus, can use dopaminergic receptors to replicate in the nervous system and are involved in viral neuropathogenesis. In addition, studies suggest that dopaminergic receptors may play a role in the progression and pathogenesis of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. When SARS-CoV-2 binds to angiotensin-converting enzyme 2 receptors on the surface of neuronal cells, the spike protein of the virus can bind to dopaminergic receptors on neighbouring cells to accelerate its life cycle and exacerbate neurological symptoms. In addition, recent research has shown that dopamine is an important regulator of the immune-neuroendocrine system. Most immune cells express dopamine receptors and other dopamine-related proteins, indicating the importance of dopaminergic immune regulation. The increase in dopamine concentration during SARS-CoV2 infection may reduce immunity (innate and adaptive) that promotes viral spread, which could lead to neuronal damage. In addition, dopaminergic signalling in the nervous system may be affected by SARS-CoV-2 infection. COVID -19 can cause various neurological symptoms as it interacts with the immune system. One possible treatment strategy for COVID -19 patients could be the use of dopamine antagonists. To fully understand how to protect the neurological system and immune cells from the virus, we need to study the pathophysiology of the dopamine system in SARS-CoV-2 infection.

Personality traits and the degree of work addiction among Polish women: the mediating role of depressiveness

Objectives

Workaholism is an addiction, however the obsessive-compulsive components alone may prove insufficient in determining its nature. The aim of the following study was to determine the mediating role of depressiveness in the relationships between workaholism and personality traits according to the five-factor model among Polish women.

Methods

The research study was carried out among 556 women residing in the West Pomerania Voivodeship in Poland. The research was based on a survey performed using a questionnaire technique. The following research instruments adapted to Polish conditions were employed to assess the incidence of work addiction among female adults: The NEO Five-Factor Inventory (NEO-FFI), The Work Addiction Risk Test (WART) Questionnaire, and The Beck Depression Inventory-BDI I-II.

Results

A positive correlation between the intensity of neuroticism and the work addiction risk was revealed (β = 0.204, p < 0.001). A partial mediation (35%) with the severity of depression symptoms as a mediating factor was observed (β = 0.110, p < 0.001). Respondents characterized by high neuroticism showed a greater severity of the symptoms of depression (β = 0.482, p < 0.001), which is a factor increasing the work addiction risk (β = 0.228, p < 0.001). No effect of extraversion intensity on the work addiction risk was found (β = 0.068, p = 0.081). Respondents characterized by a high level of extraversion displayed lower severity of the symptoms of depression (β = -0.274, p < 0.001). A negative correlation between the intensity of agreeableness and the work addiction risk was revealed (β = -0.147, p < 0.001). A partial mediation (27.8%) was observed. A positive correlation between the intensity of conscientiousness and the work addiction risk was revealed (β = 0.082, p = 0.047). Respondents characterized by a high level of conscientiousness showed a lower severity of depression symptoms (β = -0.211, p < 0.001).

Conclusion

Depressiveness plays the role of a mediator between neuroticism, extraversion, agreeableness as well as conscientiousness, and work addiction. Depressiveness is a factor which increases the risk of work addiction.

Electrocortical correlates of hypersensitivity to large immediate rewards in sensation seeking

Sensation seeking and delay discounting are strong predictors of various risk-taking behaviors. However, the relationship between sensation seeking and delay discounting remains elusive. Here, we addressed this issue by examining how high sensation seekers (HSS; N = 40) and low sensation seekers (LSS; N = 40) evaluated immediate and delayed rewards with low and high amounts during a behavioral task and an EEG task of delay discounting. Although HSS and LSS exhibited comparable discounting preference at the behavioral level, HSS relative to LSS was associated with a greater delay discounting effect at the neural level when earned rewards were large. This abnormality of reward magnitude was further corroborated by an electrocortical hypersensitivity to large immediate rewards and a stronger neural coding of reward magnitude for HSS as compared to LSS. Our findings support both the hyperactive approach theory and the optimal arousal theory in sensation seeking and have implications for the prevention and intervention targeting sensation seeking to reduce maladaptive risk-taking behaviors.

Methylphenidate undermines or enhances divergent creativity depending on baseline dopamine synthesis capacity

Catecholamine-enhancing psychostimulants, such as methylphenidate have long been argued to undermine creative thinking. However, prior evidence for this is weak or contradictory, stemming from studies with small sample sizes that do not consider the well-established large variability in psychostimulant effects across different individuals and task demands. We aimed to definitively establish the link between psychostimulants and creative thinking by measuring effects of methylphenidate in 90 healthy participants on distinct creative tasks that measure convergent and divergent thinking, as a function of individuals' baseline dopamine synthesis capacity, indexed with 18F-FDOPA PET imaging. In a double-blind, within-subject design, participants were administered methylphenidate, placebo or selective D2 receptor antagonist sulpiride. The results showed that striatal dopamine synthesis capacity and/or methylphenidate administration did not affect divergent and convergent thinking. However, exploratory analysis demonstrated a baseline dopamine-dependent effect of methylphenidate on a measure of response divergence, a creativity measure that measures response variability. Response divergence was reduced by methylphenidate in participants with low dopamine synthesis capacity but enhanced in those with high dopamine synthesis capacity. No evidence of any effect of sulpiride was found. These results show that methylphenidate can undermine certain forms of divergent creativity but only in individuals with low baseline dopamine levels.

Fish personality: meta-theoretical issues, personality dimensions, and applications to neuroscience and psychopathology

While the field of personality neuroscience has extensively focused on humans and, in a few cases, primates and rodents, a wide range of research on fish personality has emerged in the last decades. This research is focused mainly on the ecological and evolutionary causes of individual differences and also aimed less extensively at proximal mechanisms (e.g., neurochemistry or genetics). We argue that, if consistent and intentional work is made to solve some of the meta-theoretical issues of personality research both on fish and mammals, fish personality research can lead to important advances in personality neuroscience as a whole. The five dimensions of personality in fish (shyness-boldness, exploration-avoidance, activity, aggressiveness, and sociability) need to be translated into models that explicitly recognize the impacts of personality in psychopathology, synergizing research on fish as model organisms in experimental psychopathology, personality neuroscience, and ecological-ethological approaches to the evolutionary underpinnings of personality to produce a powerful framework to understand individual differences.

The association between lifelong personality and clinical phenotype in the FTD-ALS spectrum

Introduction

Frontotemporal dementia (FTD) and amyotrophic lateral sclerosis (ALS) are two phenotypes of the same neurodegenerative disease, the FTD-ALS spectrum. What determines the development of one rather than the other phenotype is still unknown. Based on the clinical observation that patients' personality seems to differ between the two phenotypes, i.e., ALS patients tend to display kind, prosocial behaviors whereas FTD patients tend to present anti-social behaviors, and that these traits are often reported as pre-existing the disease onset by caregivers, we set up to study experimentally patients' personality in their premorbid life.

Methods

We first tested for differences between groups, then tested the association between premorbid personality and current functional organization of the brain. Premorbid personality of a cohort of forty patients, 27 FTD and 13 ALS, was explored through the NEO Personality Inventory 3 (NEO-PI-3), which analyses the five main personality factors, completed by the caregiver with reference to patient's personality 20 years before symptoms onset (premorbid). A subgroup of patients underwent a brain MRI including structural and resting-state functional MRI (rsfMRI).

Results

A significant difference between FTD and ALS in premorbid personality emerged in the Openness (133.92 FTD vs. 149.84 ALS, p = 0.01) and Extraversion (136.55 FTD vs. 150.53 ALS, p = 0.04) factors. This suggests that ALS patients had been, in their premorbid life, more open to new experiences, more sociable and optimistic than FTD patients. They also showed greater functional connectivity than both FTD and a control group in the Salience resting state network, over and above differences in gray matter atrophy. Finally, there was a positive correlation between premorbid Openness and functional connectivity in the Salience network across all patients, suggesting a possible association between premorbid personality and current functional organization of the brain, irrespective of the degree of atrophy.

Discussion

Our proof-of-concept results suggest that premorbid personality may eventually predispose to the development of one, rather than the other, phenotype in the FTD-ALS spectrum.

Relationship between gamer profiles, gaming behavior, sociodemographic characteristics, and big five personality traits among French law students

BACKGROUND

Over the past 10 years, gamer profiles have been developed to understand the reason underlying players' intrinsic motivation. While the research undertaken has led to the creation of distinct models (e.g., BrainHex and Hexad typologies), there is a lack of studies on the prevalence of these profiles among a specific population and the association between the target population's profiles and their personality traits, gaming behavior, and sociodemographic characteristics.

METHODS

Thus, the present study aimed to (a) establish the gamer profiles of French undergraduate law students, (b) examine the relationships between the participants' profiles and their personality traits, gaming behavior, and sociodemographic characteristics, with a view to the development of serious games specifically intended for this population. In total, 753 French undergraduate students participated in the study, completing an online questionnaire. Data were analyzed using Latent Profile Analysis (LPA), chi-square, and ANOVA.

RESULTS

The main findings show that among participants, the two most prevalent gamers' profiles are Mastermind (45%) and Seeker (22.7%); followed by three less represented archetypes: Conqueror (12.9%), Daredevil (9.7%), and Achiever (9.7%). These archetypes are associated with the participants' Big Five personality traits. Specifically, Daredevils, Masterminds, and Seekers have high mean scores on Extraversion (p < .001); Achievers and Seekers have high mean scores on Agreeableness (p < .001); Seekers and Achievers have high mean scores on Neuroticism (p < .001); and Seekers, Masterminds, and Achievers have high mean scores on Openness (p < .001). The unveiled profiles are also significantly associated with the participants' gaming behavior including their playing frequency (p < .001), game types (p = .031), and sociodemographic characteristics (p < .001). For example, Masterminds are more likely to be female than the other four profiles (p < .001), while Conquerors and Daredevils are more likely to have a low socio-economic status compared to those with intermediate and high socio-economic status (p = .49).

CONCLUSION

These findings can be used to design serious/educational games tailored to the studied population.

Approaches to Studying and Improving Social Motivation in Schizophrenia

Social motivation impairments, or "asociality," have long been considered a core clinical feature of schizophrenia. Although the prevalence and pervasive negative impact of poor social motivation is well-documented, our understanding is limited regarding causal mechanisms. Advances in definition, conceptualization, and characterization are needed to inform research aimed at understanding these mechanisms and developing effective interventions. This theme issue is intended to accelerate efforts to study and treat social motivation in schizophrenia by synthesizing the current knowledge and providing new frameworks to guide future research in this area.

The impact of sensation seeking personality trait on acute alcohol-induced disinhibition

BACKGROUND

Acute alcohol-related behavioral disinhibition has been well studied. But whether individual differences in the personality trait sensation seeking affect alcohol-induced behavioral disinhibition remains uncertain.

METHODS

The present study used functional near-infrared spectroscopy (fNIRS) technique and a response inhibition task (i.e., Go/No-Go) to determine the impact of the sensation seeking trait on the relationship between acute alcohol administration and inhibitory control capacity, and further investigate the neural mechanisms underlying this behavioral effect. Twenty-five high-sensation seekers and twenty-six low-sensation seekers were enrolled in this study. These participants attended two sessions: once for alcohol intake (0.5g/kg) and once for placebo intake (0g/kg).

RESULTS

Our results showed that high-sensation seekers relative to low-sensation seekers showed a significant decrease in inhibition accuracy under alcohol versus the placebo condition. Moreover, reduced prefrontal activity following acute alcohol consumption was more pronounced in high-sensation seekers compared with low-sensation seekers.

CONCLUSIONS

These findings showed that alcohol-induced behavioral disinhibition was affected by the personality trait sensation seeking and that recruitment of the prefrontal cortex contributed to the observed behavioral effect.

Revising a Self-Regulation Phenotype for Depression Through Individual Differences in Macroscale Brain Organization

Self-regulation denotes the processes by which people initiate, maintain, and control their own thoughts, behaviors, or emotions to produce a desired outcome or avoid an undesired outcome. Self-regulation brings the influence of distal factors such as biology, temperament, and socialization history onto cognition, motivation, and behavior. Dysfunction in self-regulation represents a contributory causal factor for psychopathology. Accordingly, we previously proposed a risk phenotype model for depression drawing from regulatory focus theory and traditional task-based fMRI studies. In this article, we revise and expand our risk phenotype model using insights from new methodologies allowing quantification of individual differences in task-free macroscale brain organization. We offer a set of hypotheses as examples of how examination of intrinsic macroscale brain organization can extend and enrich investigations of self-regulation and depression. In doing so, we hope to promote a useful heuristic for model development and for identifying transdiagnostic risk phenotypes in psychopathology.

Anger, agency, risk and action: a neurobehavioral model with proof-of-concept in healthy young adults

Introduction

Anger can engender action by individuals and groups. It is thus important to understand anger's behavioral phenotypes and their underlying neural substrates. Here, we introduce a construct we term agentic anger, a negatively valenced internal state that motivates action to achieve risky goals. We evaluate our neurobehavioral model via testable hypotheses in two proof-of-concept studies.

Study 1 Methods

Study 1 used the Incentive Balloon Analogue Risk Task in a within-subjects, repeated measures design in 39 healthy volunteers to evaluate: (a) impact of blockade of reward on agentic anger, assessed by self-reports of negative activation (NA), (b) impact of achievement of reward on exuberance, assessed by self-reports of positive activation (PA), (c) the interrelationship of these valenced states, and (d) their relationship with personality.

Study 1 Results

Task-induced NA was positively correlated with task-induced PA, risk-taking on the task and trait Social Potency (SP), a measure of trait agency and reward sensitivity on the Multidimensional Personality Questionnaire Brief-Form.

Study 2 Methods

Study 2 assessed functional MRI response to stakes for risk-taking in healthy volunteers receiving 20 mg d-amphetamine in a double-blinded, placebo-controlled crossover design (N = 10 males), providing preliminary information on ventral striatal response to risky rewards during catecholamine activation.

Study 2 Results

Trait SP and task-induced PA were strongly positively related to catecholamine-facilitated BOLD response in the right nucleus accumbens, a brain region where DA prediction error signal shapes action value and selection. Participants' task-induced NA was strongly positively related with trait SP and task-induced PA, replicating the findings of Study 1.

Discussion

Together these results inform the phenomenology and neurobiology of agentic anger, which recruits incentive motivational circuitry and motivates personal action in response to goals that entail risk (defined as exposure to uncertainty, obstacles, potential harm, loss and/or financial, emotional, bodily, or moral peril). Neural mechanisms of agency, anger, exuberance, and risk-taking are discussed, with implications for personal and group action, decision-making, social justice, and behavior change.

Engineered highs: Reward variability and frequency as potential prerequisites of behavioural addiction

Influential learning-based accounts of substance addictions posit the attribution of incentive salience to drug-associated cues, and its escalation by the direct dopaminergic effects of drugs. In translating this account to disordered gambling, we have noted how the intermittent nature of monetary rewards in gambling (i.e. the variable ratio) may allow for analogous learning processes, via effects on dopaminergic signalling. The aim of the present article is to consider how multiple sources of reward variability operate within modern gambling products, and how similar sources of variability, as well as some novel sources of variability, also apply to other digital products implicated in behavioural addictions, including gaming, shopping, social media and online pornography. Online access to these activities facilitates not only unparalleled accessibility but also introduces novel forms of reward variability, as seen in the effects of infinite scrolls and personalized recommendations. We use the term uncertainty to refer to the subjective experience of reward variability. We further highlight two psychological factors that appear to moderate the effects of uncertainty: 1) the timecourse of uncertainty, especially with regard to its resolution, 2) the frequency of exposure, allowing temporal compression. Collectively, the evidence illustrates how qualitative and quantitative variability of reward can confer addictive potential to non-drug reinforcers by exploiting the psychological and neural processes that rely on predictability to guide reward seeking behaviour.

A comprehensive review on the role of testosterone on the neurobehavioral systems implicated in the reinforcement sensitivity theory of personality

OBJECTIVES

The Reinforcement Sensitivity Theory (RST) is a neuropsychological theory of personality emphasizing approach and avoidance as the two core behavioral aspects. Approach is represented by the behavioral approach system (BAS). Avoidance is represented by the behavioral inhibition system (BIS) and the fight-flight-freeze system (FFFS). Although the influence of testosterone on human behavior has been demonstrated, few studies have investigated the relation between testosterone and the RST. The aim of this narrative review was to decipher the possible role of testosterone on the biological systems involved in the RST in humans.

METHODS

Google scholar, PubMed, PsycARTICLES, PsycINFO, Scopus and Cochrane library databases were interrogated using keywords such as testosterone, BIS, BAS, FFFS, personality, reinforcement sensitivity theory.

RESULTS

Seven original articles, published between 2009 and 2022, assessing the relation between testosterone and the systems implicated in the RST, were included. The results of these studies suggested the presence of a possible positive relation between testosterone and the BAS. However, the impact of testosterone on the BIS and/or FFFS seems to be less clear.

DISCUSSION

The consistency in the results supporting the presence of a positive relation between testosterone and the BAS might lead to the consideration of testosterone as a potential correlate in the clinical assessment of several psychopathologies. The inconsistency in the conclusions regarding the impact of testosterone on the BIS and/or the FFFS might be attributed to the different questionnaires used as measurement tools. Additional research remains needed.

Workplace loneliness mediates the relationship between perceived organizational support and job performance: Differing by extraversion

This study investigated the mediating role of workplace loneliness relating perceived organizational support to job performance, as well as the moderating role of extraversion in such relationship. 332 full-time Chinese employees from various enterprises voluntarily participated in the two-wave surveys via either paper-and-pencil or online survey conducted at Credamo and Tencent Questionnaire website. Hierarchical regression and bootstrapping analyses were employed to examine the hypotheses. Results indicated that workplace loneliness partially mediates the linkage between perceived organizational support and job performance; extraversion serves as a moderator in the relationship between workplace loneliness and job performance, as well as the mediating role of workplace loneliness linking perceived organizational support to job performance, such that the relationship is stronger when extraversion is high. Supplementary analyses revealed that social companionship, but not emotional deprivation, serves as a mediator in the relationship between perceived organizational support and job performance; extraversion enhanced the direct influence of social companionship on job performance, as well as the indirect influence of perceived organizational support on job performance via social companionship. Theoretical and practical implications are discussed.

Motive-Specific Affective Contingencies and Their Relevance for Personality and Motivated Behavior

Individuals differ in the tendency to derive pleasure out of motive-specific incentives, such as being socially included or attaining power. Multiple theoretical approaches have proposed that such motive-specific positive affective contingencies (PACs) are central building blocks of motive dispositions and personality more broadly. In the current research, we put this claim to test and investigated individual differences with regard to motive-specific PACs in the affiliation and power domains. We measured PACs via spontaneous emotional reactions to motive-specific cues, as assessed by affect ratings and electromyographic (EMG) recordings of smile responses. Both of these PAC operationalizations were highly internally consistent and moderately to highly stable across time. Furthermore, motive-specific PACs were linked in a manner consistent with theory to measures of motive dispositions and to personality traits with motivational underpinnings (i.e., extraversion, agreeableness, and narcissism). Finally, in the affiliation domain, motive-specific PACs were linked to objectively assessed, key motivational outcomes (i.e., attentional orientation, behavior in daily life, and in the laboratory). Taken together, the findings underscore the relevance of affective contingencies for the understanding of personality and motivated behavior.

Electrophysiological activity from over the cerebellum and cerebrum during eye blink conditioning in human subjects

We report the results of an experiment in which electrophysiological activity was recorded from the human cerebellum and cerebrum in a sample of 14 healthy subjects before, during and after a classical eye blink conditioning procedure with an auditory tone as conditional stimulus and a maxillary nerve unconditional stimulus. The primary aim was to show changes in the cerebellum and cerebrum correlated with behavioral ocular responses. Electrodes recorded EMG and EOG at peri-ocular sites, EEG from over the frontal eye-fields and the electrocerebellogram (ECeG) from over the posterior fossa. Of the 14 subjects half strongly conditioned while the other half were resistant. We confirmed that conditionability was linked under our conditions to the personality dimension of extraversion-introversion. Inhibition of cerebellar activity was shown prior to the conditioned response, as predicted by Albus (1971). However, pausing in high frequency ECeG and the appearance of a contingent negative variation (CNV) in both central leads occurred in all subjects. These led us to conclude that while conditioned cerebellar pausing may be necessary, it is not sufficient alone to produce overt behavioral conditioning, implying the existence of another central mechanism. The outcomes of this experiment indicate the potential value of the noninvasive electrophysiology of the cerebellum.

Exploring users' content creation and information dissemination behavior in social media: The moderating effect of social presence

Users' personality traits reveal different social media behavior characteristics. In order to explore the intrinsic relationships between personality traits and social media behavior, this study analyzes the influence of users' personality traits on social media content creation and information dissemination behavior, as well as the moderating effect of social presence. We collect users' personality data via questionnaires, crawl social media behavior data of samples from social media sites, and then establish regression models to test the research hypotheses. The results show that extraversion has a positive impact on content creation and information dissemination behavior, conscientiousness has a negative impact on content creation behavior, openness and agreeableness have no significant impact on social media behavior, and social presence has significant moderating effects on the relationships between personality traits and social media behavior.