Dr Eilish Duke

The last part of the book will focus on therapeutic interventions for Internet addiction. This book combines a scholarly introduction with state-of-the-art research in the characterization of Internet addiction.

The second edition of this successful book provides further and in-depth insight into theoretical models dealing with Internet addiction, as well as includes new therapeutical approaches.

The authors regret to inform the scientific community about changes to a paper recently published in Psychoneuroendocrinology. In this paper we reported that two haplotypes of the NR3C1 and NR3C2 genes were significantly associated with a stress-induced response of the HPA axis. Furthermore, there was a NR3C2 haplotype x cortisol response interaction on attentional performance in our sample. However, a few months ago we were contacted by a reader who pointed out that our reported cortisol values seemed quite high. Although cortisol values reported in the literature show a large variation of up to 250% dependent on measurement method (Miller et al., 2013b), we took the comments by our colleague as an opportunity to critically re-evaluate our data and found that many of our cortisol values exceeded the 95% confidence interval provided in the instruction manual of our reagent kit. After extensive re-analyses, we came to the conclusion that the calibrants of some of the reagent kits employed had inaccurate concentrations, as the raw values of some of the calibrants differed strongly from the target values provided in the manual. Unfortunately, this error produced abnormally high cortisol values in our samples, although the cortisol slopes showed the typical and expected pattern after an acute stress induction. Therefore, we reanalyzed our whole sample by means of the ELISA absorption method (in lieu of the original luminescence assay). While this produced more plausible and accurate cortisol values within the expected range, it also led to several changes to the previous results. These changes notwithstanding, the main results of our study could be confirmed. Specifically, we had to exclude 5 subjects due to missing cortisol data (i.e. at least one of the five samples from the participant was too small to allow two new measurements) or biologically highly implausible cortisol slopes. Secondly, we divided our sample into responders and non-responders using a different criterion due to the altered measurement method. Miller et al. (2013a,b) suggest a cut-off of 1.5 nmol/l cortisol increase to separate responders and non-responders when determining cortisol data by luminescence immunoassays. Alternatively, they suggest the baseline-to-peak increase in percent as criterion because of the huge variation between different methods. They report that given a coefficient of intra-assay variation (CV) of 8%, a baseline-to-peak increase of 15.5% marks the upper bound of the 95% confidence interval independent of the method used to determine cortisol values. As we used an ELISA absorption assay, we decided to separate responders and non-responders by the percentage baseline-to-peak increase. However, our CV was 13.3% instead of 8% taken as a basis by Miller et al. (2013a,b). Therefore, we proportionally raised the threshold to a more conservative criterion of 25%. Hence, every subject responding with an increase of at least 25% from t0 to t55 was now classified as a cortisol responder in the reanalyses. Categorizing our sample using this new criterion resulted in n = 70 cortisol non-responders and n = 51 responders. Due to the new criterion and the excluded participants, the classification of responder groups changed leading to the following diverging results: After the re-analyses, the mean cortisol response (t 55 –t 0 ) after the stress induction was M = 1.12 nmol/l (SD = 3.75). Responder groups now differed in their baseline cortisol level (p =.004) and there was still an interaction of responder group by time on cortisol levels (F (2.683,116) = 26.359, p <.001, η

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The 2D:4D-Ratio, as an indirect measure of the fetal testosterone to estradiol ratio, is potentially very important for understanding and explaining different personality traits. It was the aim of the present study to replicate the findings from Fink et al. (2004) about the relation between individual differences in 2D:4D-Ratios and the Five Factor Model in different cultural groups. Therefore a sample of n = 78 Chinese and n = 370 German participants was recruited. Every participant provided hand scans of both hands, from which 2D:4D-Ratios were computed. Moreover, all participants filled in the NEO Five Factor Inventory (NEO-FFI). Significant sex differences were found for ratios of both hands in the expected direction, with females showing higher ratios than males. With respect to links between personality and the digit ratio, a positive association was observed between 2D:4D-Ratio and Neuroticism in females, as shown in the earlier study. These findings were observed in both female subsamples from China and Germany, as well as in the full sample of participants. But in contrast to the results for the whole and the German female sample, where 2D:4D-Ratio of both hands were related to Neuroticism, in the Chinese female sample only left hand 2D:4D-Ratio was significantly and positively related to Neuroticism. There were no significant correlations found in any of the male samples. Thus, prenatal exposure to sex steroids appears to influence the personality factor Neuroticism in females specifically. This finding potentially has implications for mental health, as Neuroticism has been shown to be a risk factor for various forms of psychopathology.

The present paper provides insight into an emerging research discipline calledPsychoinformatics. In the context ofPsychoinformatics, we emphasize the cooperation between the disciplines of psychology and computer science in handling large data sets derived from heavily used devices, such as smartphones or online social network sites, in order to shed light on a large number of psychological traits, including personality and mood. New challenges await psychologists in light of the resulting “Big Data” sets, because classic psychological methods will only in part be able to analyze this data derived from ubiquitous mobile devices, as well as other everyday technologies. As a consequence, psychologists must enrich their scientific methods through the inclusion of methods from informatics. The paper provides a brief review of one area of this research field, dealing mainly with social networks and smartphones. Moreover, we highlight how data derived fromPsychoinformaticscan be combined in a meaningful way with data from human neuroscience. We close the paper with some observations of areas for future research and problems that require consideration within this new discipline.

Over the past few years, a growing amount of research has considered the links between personality and overuse (pathological use) of the Internet. Given the partial overlap between problematic Internet and smartphone use (PIU and PSU, respectively), the present study seeks to investigate whether the same personality traits can be linked to overuse of both platforms. A total of 612 participants (177 males/435 females, mostly students) completed questionnaires assessing both PIU and PSU, and the NEO Five Factor Inventory (NEO-FFI) to measure the Five-Factor Model of Personality and the Self-Directedness scale of the Temperament and Character Inventory. Our results indicate the existence of a common personality structure linked to both PIU and PSU. Interestingly, the associations between personality and PIU were higher than those concerning PSU. Low Self-Directedness appears to be the best predictor of overuse on both digital platforms. Therefore, lower willpower anchored in the personality trait Self- Directedness may reflect the core of digital additive tendencies.

The advent of the smartphone has dramatically altered how we communicate, navigate, work and entertain ourselves. While the advantages of this new technology are clear, constant use may also bring negative consequences, such as a loss of productivity due to interruptions in work life. A link between smartphone overuse and loss of productivity has often been hypothesized, but empirical evidence on this question is scarce. The present study addressed this question by collecting self-report data from N = 262 participants, assessing private and work-related smartphone use, smartphone addiction and self-rated productivity. Our results indicate a moderate relationship between smartphone addiction and a self-reported decrease in productivity due to spending time on the smartphone during work, as well as with the number of work hours lost to smartphone use. Smartphone addiction was also related to a greater amount of leisure time spent on the smartphone and was strongly related to a negative impact of smartphone use on daily non-work related activities. These data support the idea that tendencies towards smartphone addiction and overt checking of the smartphone could result in less productivity both in the workplace and at home. Results are discussed in relation to productivity and technostress.

Although HPA – axis reactivity has repeatedly been related to cognitive functioning, ambiguity remains regarding the direction of the effect, i.e. whether it benefits or impairs functioning. Genetic factors that contribute to HPA – axis reactivity on the one hand and to cognitive functioning on the other could therefore help clarify the association between stress and cognition. We genotyped 10 single nucleotide polymorphisms (SNPs) on the NR3C1 gene (rs10482682, rs33389, rs10482633, rs10515522, rs2963156, rs4128428, rs9324918, rs41423247, rs6189, rs10052957) coding for the glucocorticoid receptor (GR) and 4 SNPs on the NR3C2 gene (rs6810951, rs4635799, rs11099695, rs2070950) coding for the mineralocorticoid receptor (MR) and required N = 126 healthy males to perform tasks assessing attention and reasoning before and after experiencing an acute laboratory stressor (the Socially Evaluated Cold Pressor Test, SECPT). Haplotype analyses revealed significant effects of NR3C1 (p = 0.011) and NR3C2 (p = 0.034) on cortisol stress response. NR3C2 also influenced attentional performance via an interaction with stress-induced cortisol response (p < 0.001). Neither NR3C1 haplotype nor NR3C2 haplotype was associated with reasoning abilities. Results suggest that the association between stress induced cortisol reactivity and cognition strongly depends on genetic variation. The idea of an optimal arousal level depending on stress reactivity and genetic disposition is discussed.

Heightened sensitivity to losses, known as loss aversion, is a putative avoidance behaviour, which commonly influences decision-making, particularly in economic scenarios where participants have a 50/50 chance of winning or losing money. Evidence from neuropsychology, EEG and TMS research suggests individual differences in loss aversion may be explained by neural differences in the lateralisation of the right hemisphere. 40 healthy participants underwent an EEG recording during resting state and subsequently performed a behavioural loss aversion task, in which they had an equal chance of winning or losing money. EEG asymmetry in the alpha band at central and posterior sites was associated with individual differences in behavioural loss aversion. This asymmetry was driven by a combination of increased activation in the right hemisphere and decreased activation in the left hemisphere and the site of this asymmetry differed for females and males. These findings are discussed in relation to behavioural avoidance.

Introduction The present study sought to address core issues in the association between personality and the putative disordered use of Facebook. First, to redress the issue of generalisation from samples solely recruited from Facebook, we sought to explore personality differences between users and non-users of Facebook. Second, we aimed to investigate associations between personality and Facebook Use Disorder. The present study contributes a novel perspective to extant research on this topic by moving beyond the broad Big Five of personality, to explore possible relationships between Facebook use and sub-facets of the Big Five; all analyses were additionally controlled for confounding effects of demographic variables. Methods 3,835 (n = 2,366 males) participants completed socio-demographic variables, the Big Five Inventory and stated their user status on Facebook (i.e. user versus non-user). Facebook-users also completed a Facebook Use Disorder scale assessing addictive tendencies towards Facebook use. Results Facebook users reported higher levels of extraversion and lower levels of conscientiousness compared to non-users. Tendencies towards Facebook Use Disorder correlated negatively with conscientiousness and positively with neuroticism in both males and females. Conclusions The present results indicate that research samples drawn from Facebook users may be biased with regard to personality (extraversion, conscientiousness). Moreover, certain personality traits – conscientiousness and neuroticism – which may influence the tendency towards Facebook Use Disorder are discussed.

Since the emergence of the SARS-CoV-2 pandemic in December 2019 about 500,000 people died within the first 6 months. The virus itself, as well as the related political decisions, intensified an increasing feeling of fear in billions of people worldwide. However, while some people remained unperturbed, others experienced panic over the current situation. In order to investigate individual differences in the perceptions, emotions and behaviors in response to the Coronavirus pandemic, an online survey was conducted between 6th and 27th of March 2020. Participants included 7309 individuals from 96 countries, who provided information on socio-demographics, personality, political orientation and general life satisfaction. To determine the specificity of fear of Coronavirus, we also investigated fear related to two other current political issues: the refugee and the climate crises. Overall, in parallel with the escalation of the pandemic, fear of Coronavirus increased significantly over the 22-day period, with the strongest predictors being the personality variable neuroticism, as well as education, sex and being an at-risk person. A detailed longitudinal analysis of the largest sample, Germany, revealed that political orientation was also an important predictor of fear of Coronavirus. Specifically, conservatives were more afraid of Coronavirus than liberals. However, as the perceived threat of the virus increased, the influence of political orientation disappeared, whereas personality remained a stable predictor. The pattern of results regarding the perceived threat of the refugee and climate crises painted a different picture: political orientation was by far the best predictor, more important even than personality. Conservatives were more worried about the refugees, and liberals about climate change. Cross-cultural analyses showed pronounced differences between countries, dependent on the crisis. Nonetheless, the importance of personality for the prediction of fear of Coronavirus remained stable over time and across the world within the investigated 22-day period.

Gender and personality traits influence risk proneness in the context of financial decisions. However, most studies on this topic have relied on either self-report data or on artificial measures of financial risk-taking behavior. Our study aimed to identify relevant trading behaviors and personal characteristics related to trading success. N = 108 Caucasians took part in a three-week stock market simulation paradigm, in which they traded shares of eight fictional companies that differed in issue price, volatility, and outcome. Participants also completed questionnaires measuring personality, risk-taking behavior, and life stress. Our model showed that being male and scoring high on self-directedness led to more risky financial behavior, which in turn positively predicted success in the stock market simulation. The total model explained 39% of the variance in trading success, indicating a role for other factors in influencing trading behavior. Future studies should try to enrich our model to get a more accurate impression of the associations between individual characteristics and financially successful behavior in context of stock trading.

Analogue zeitgebers such as wristwatches and alarm clocks are essential for structuring everyday life. Since the dawn of the digital revolution - particularly since the advent of the smartphone - mobile phones have increasingly replaced analogue zeitgebers as a means of telling time. This functionality may prove problematic, in that it may contribute to the overuse of digital media (e.g. when checking the time turns into extended use of other smartphone utilities, including Internet-based applications). Of N = 3084 participants, 45% reported wearing a wristwatch and 67% used an analogue alarm clock. We observed that participants who reported using analogue zeitgebers used their mobile-/smartphone significantly less. Use of analogue zeitgebers may prove a practical tool for therapeutic and preventative interventions for problematic Internet use in an increasingly digital age.

Abstract

Vaccine hesitancy is one of the top 10 threats to public health. The COVID-19 pandemic and associated vaccinations marked a watershed moment for vaccine hesitancy, with highly publicized anti-vaccine protests, and widespread misinformation and distrust of the novel vaccines. This mixed-method survey sought to provide a nuanced understanding of vaccine hesitancy and hesitant vaccine adopters in the context of the COVID-19 vaccination. N = 410 participants completed an online survey comprising a battery of psychometric measures of vaccine hesitancy, personality, conspiracy belief, and political affiliation. N = 134 participants, who identified as vaccine hesitant toward the novel vaccine, provided additional written qualitative responses detailing the reasons they were hesitant about accepting the COVID-19 vaccination. Quantitative findings point to higher hesitancy among males, those with high-school and undergraduate levels of education, mixed- and minoritized ethnic groups (Black, Asian), and those higher in Right-Wing Authoritarian and Conspiracy beliefs. Qualitative data unveiled six themes underpinning hesitancy: side-effect concerns; Covid risk perception; conspiracy and religious beliefs; psychological reactance against perceived coercion; a perceived lack of information; and distrust of Government/medical establishments. Crucially, an acknowledgment of the benefits of the vaccine, e.g. in terms of protecting others, distinguished vaccine hesitant adopters from refusers. Implications of the findings are discussed with a view to informing policy and public health campaigns targeting vaccine hesitant adopters.

Medial-frontal negativity occurring ~200-300 ms post-stimulus in response to motivationally salient stimuli, usually referred to as feedback-related negativity (FRN), appears to be at least partly modulated by dopaminergic-based reward prediction error (RPE) signaling. Previous research (e.g., Smillie et al., 2011) has shown that higher scores on a putatively dopaminergic-based personality trait, extraversion, were associated with a more pronounced difference wave contrasting unpredicted non-reward and unpredicted reward trials on an associative learning task. In the current study, we sought to extend this research by comparing how trait measures of reward sensitivity, impulsivity and extraversion related to the FRN using the same associative learning task. A sample of healthy adults (N = 38) completed a battery of personality questionnaires, before completing the associative learning task while EEG was recorded. As expected, FRN was most negative following unpredicted non-reward. A difference wave contrasting unpredicted non-reward and unpredicted reward trials was calculated. extraversion, but not measures of impulsivity, had a significant association with this difference wave. Further, the difference wave was significantly related to a measure of anticipatory pleasure, but not consummatory pleasure. These findings provide support for the existing evidence suggesting that variation in dopaminergic functioning in brain "reward" pathways may partially underpin associations between the FRN and trait measures of extraversion and anticipatory pleasure. © 2014 Cooper, Duke, Pickering and Smillie.