The effects of behavioral inhibition/approach system as predictors of Internet addiction in adolescents

Validation of the brief screening of Social Network Addiction Risk

INTRODUCTION

This study aims to develop a valid and reliable tool to evaluate social network behavior in young adults.

METHODS

To validate the Brief screening for Social Network Addiction Risk (BSNA), data from 776 Italian young adults (64.3 % of women) were collected. The suitability of the instrument was statistically assessed. Experts' opinions, item reliability, exploratory and confirmatory factor analyses, and convergent validity were adopted to validate the BSNA items. Internal consistency coefficients were also calculated.

RESULTS

According to the statistical analyses, a 2-factor structure was confirmed. The two scales of BSNA assess behavior and motivation frame of social networks use. The second order model proved a global score of risk of social network addiction. Fit indices highlighted the high goodness of the model. Preliminary analyses of prevalence estimated that about 18 % of participants reported problematic Social Network use, which may overtime represent a marker of addictive behavior.

CONCLUSION

The final version of the BSNA, with 11 items evaluated on a 5-point Likert- scale, is a short but valid tool for measuring the risk of social network addiction. It represents a promising screening tool aimed to not overpathologize a behavior, but to furnish adequate insight into this phenomenon.

Does parents' perceived style of setting limits to gaming matter? The interplay between profiles of parental mediation and BIS/BAS sensitivity in problematic gaming and online gambling

INTRODUCTION

Parents try to prevent possible negative outcomes associated with gaming by setting rules on their adolescent's gaming behavior (i.e., restrictive mediation). Parents can use either more autonomy-supportive or more controlling styles to communicate those rules. Using a person-centered approach, this study aims to, first, identify profiles of parents' perceived degree of restrictive mediation in gaming and styles of communicating these rules (i.e., autonomy-supportive and controlling); second, to examine how adolescents in different profiles differ in terms of maladaptive gaming outcomes (i.e., problematic gaming, simulated, and online gambling); third, to investigate the moderating role of gaming frequency and adolescents' personality (i.e., behavioral inhibition system [BIS] sensitivity and behavioral activation system [BAS] sensitivity) in the associations between the parental profiles and the outcomes.

METHODS

The study used quantitative, cross-sectional survey data from Belgian adolescents (N = 1651, mean age = 14.00 years, 51.2% boys), collected between November 2021 and February 2022 in schools.

RESULTS

Cluster analysis yielded four profiles of perceived restrictive mediation: an exclusively controlling one, an autonomy-supportive one, one where parents used a perceived mix of both communication styles, and one where there was an overall perceived lack of restrictive mediation. Adolescents in the controlling profile displayed the most maladaptive outcomes. Some of the associations between the parental profiles and the outcomes were stronger for more frequent gamers and for adolescents scoring higher on both BIS and BAS sensitivity.

CONCLUSION

Associations between the parental profiles and gaming outcomes were theoretically meaningful, yet small in terms of effect size.

The longitudinal impact of reinforcement sensitivity on internet addiction among college students: the mediating role of self-control

Introduction

As the rapid expanding of internet technology, it is necessary to pay attention to the factors that predict Internet addiction. This study aimed to investigate the longitudinal impact of reinforcement sensitivity on internet addiction among college students and the mediating role of self-control.

Methods

The study involves two follow-up assessments with a 5-month interval. 383 college students' reinforcement sensitivity, self-control, and internet addiction were measured at two-time points.

Results

①The revised Behavioral Approach System (r-BAS) at Time Point 1 (T1) could predict both T1 and Time Point 2 (T2) internet addiction through the complete mediation of T1 self-control. ②The revised Behavioral Inhibition System (r-BIS) at T1, along with the Fight/Flight/Freeze System (FFFS), can predict T1 and T2 internet addiction through the partial mediation of T1 self-control.

Conclusion

Reinforcement sensitivity can predict current and future internet addiction, with self-control playing a mediating role. This study provides longitudinal experimental evidence for the revised Reinforcement Sensitivity Theory (r-RST), further revealing the underlying mechanisms through which reinforcement sensitivity influences internet addiction. Additionally, it has implications for clinical intervention.

Self-regulation profiles in addictive behaviors among adolescents: A transdiagnostic approach

Dual-pathway models suggest that poor self-regulation (immature regulatory combined with strong reactive processes) is an important factor underlying addictive behaviors among adolescents. This study examined whether there are different self-regulation profiles among community adolescents, and how these profiles are related to the presence, severity and comorbidity of different addictive behaviors. A community sample of 341 adolescents (54.5% female; 13-17 years) was recruited. Participants self-reported on regulatory (inhibitory control) and reactive (reward and punishment sensitivity) processes, as well as on different addictive behaviors (binge eating, tobacco-, cannabis- and alcohol use, gaming, gambling and pathological buying). A model-based clustering analysis found evidence for three meaningful profiles: 'impulsive/under-controlled', 'anxious' and 'protective'. The 'impulsive/under-controlled' profile was characterized by the highest prevalence and severity of cannabis use and the most severe alcohol use. The 'impulsive/under-controlled' and 'protective' profiles demonstrated the highest prevalence and severity of tobacco use, whereas the 'impulsive/under-controlled' and 'anxious' profiles showed the highest binge eating scores. Adolescents who reported more than three types of addictive behaviors generally belonged to the 'impulsive/under-controlled' profile. The profiles did not differ for gaming, gambling and pathological buying. The 'impulsive/under-controlled' profile emerged as the most vulnerable profile in the context of addictive behaviors (especially for binge eating and substance use).

The Role of BDNF and NPY Levels, Effects of Behavioral Systems and Emotion Regulation on Internet Addiction in Adolescents

Internet addiction (IA), one of the behavioral addictions, is also related to impulsivity. Although studies on its etiology and risks continue, the number of studies is limited. In this study, we aimed to assess the roles of behavioral systems, emotional regulation (ER), and impulsivity in the development of IA in adolescents and also to assess the relationship between all these clinical parameters and brain-derived neurotrophic factor (BDNF) and neuropeptide Y (NPY). Forty-two adolescents with IA and 30 healthy controls (ages 12 -17) were included in the study. Self-reported measures included the Internet Addiction Scale. (IAS), Behavioral Activation and Behavioral Inhibition Scale (BAS/BIS), Barratt. Impulsiveness Scale-11 (BIS-11), and Difficulties in Emotion Regulation Scale-16 (DERS-16) were used for the assessment of the participants. The levels of plasma brain BDNF and NPY were evaluated with the ELISA method. BAS/BIS subscale scores, BIS-11, and DERS-16 scale total scores were found to be statistically significantly higher, while BDNF and NPY levels were found to be lower in adolescents with IA compared to the healthy controls. IA severity was not found to correlate with both BDNF and NPY. IA was found to be more related to BIS than to BAS. There is a need for further studies evaluating developmental features and possible diagnostic biomarkers that may be associated with IA in adolescents.

Comparison of behavioral activation/inhibition systems, emotional regulation difficulties, and selective attention in adolescents with and without parents

Existing literature has established a relationship between adverse childhood experiences and negative outcomes in cognitive and affective functioning. However, further research is needed to thoroughly understand and validate these findings. In this regard, the current study aimed to compare behavioral activation/inhibition systems, emotional regulation difficulties, and selective attention in adolescents with and without parents. A sample of 70 adolescents (M age = 16.36, SD = 1.09, 48.57% female) with caretakers from schools and 55 parentless adolescents (M age = 16.58, SD = 1.28, 52.00% female) from orphanage centers in Tehran were recruited and completed the measures tapping behavioral activation/inhibition systems, emotion dysregulation difficulties, and selective attention. The results revealed that parentless adolescents exhibited significantly higher levels of behavioral activation/inhibition scores, emotion regulation difficulties, and impaired selective attention. These findings suggest that the absence of parents during the early years of life may have detrimental effects on behavioral inhibition and activation systems, emotional regulation abilities, and selective attention capabilities. The implications of these findings are further discussed.

Problematic social media use is associated with depression and similar to behavioral addictions: Physiological and behavioral evidence

While many studies have examined the relationship between problematic social media use (PSMU) and mental health disorders, little is known about reward responsiveness mechanisms that might be driving this relationship and the neurophysiological characteristics of PSMU. We surveyed 96 undergraduate students at a private liberal arts college in upstate NY. PSMU was assessed using the Social Media Disorder Scale. Fourteen Individuals endorsing in five or more and three or less categories on the Social Media Disorder Scale were offered and underwent resting state QEEG. Mental health was assessed with the Center for Epidemiological Studies Depression Scale Short Form, Social Interaction Anxiety Scale, Penn State Worry Questionnaire, the 10-item Perceived Stress Scale, and a locally developed measure of Substance Use Disorder. Reward and motivational systems were studied using the Brief Sensation Seeking Scale, Behavioral Inhibition/Behavioral Activation Scale, and Temporal Experience of Pleasure Scale. SMDS scores were associated with poorer mental health on all measures except substance use. SMDS scores were positively associated with the behavioral inhibition scale, and the anticipatory pleasure scale. QEEG results revealed a negative association of high PSMU and right central and frontal lobeta, right central beta, and a positive association with frontal alpha asymmetry. The study replicates findings that PSMU is associated with mental health issues. Further the pattern of reward response is different compared with other addictive behaviors. QEEG results are consistent with previous work in substance use and depression.

Role of innate and acquired resilience in behavioral system, mental health, and internet addiction among Japanese adolescents in the COVID-19 pandemic

Background

This study examines mediation models in which behavioral inhibition and activation systems (BIS/BAS) impact internet addiction through mental health and the moderating roles of innate and acquired resilience in the models.

Methods

The data set used in this study was a cross-sectional survey among 952 adolescents in July 2021. Internet Addiction Test, Fear of COVID-19 Scale, BIS/BAS scales, and Depression Self-Rating Scale were used for analysis. After controlling for gender, the mediation and moderated mediation models were examined.

Results

The results revealed that depressive symptoms partially mediated the relationship between BIS and internet addiction and between BAS-fun-seeking (BAS-FS) and internet addiction. Innate and acquired resilience moderated the relationship between depressive symptoms and internet addiction. The indirect effect of innate and acquired resilience on internet addiction via depressive symptoms was statistically significant in both low and high innate and acquired resilience. The results of conditional indirect effect analysis indicated that the depressive symptoms-internet addiction association decreased with the increase of innate or acquired resilience level.

Discussion

Our results suggested that depression symptoms played a significant mediation role in the relationships between BIS/BAS and internet addiction, and higher innate and acquired resilience was associated with a reduced risk of internet addiction. BIS/BAS may be a risk for internet dependence via mental health, and innate and acquired resilience appears to serve as a protective factor.

Grit Perseverance, Not Passion, Moderates the Association Between Behavioral Inhibition/Approach System and Internet Addiction in Adolescents

Background

Research on the links between the behavioral inhibition and approach systems (BIS/BAS), and internet addiction (IA) in adolescents has been inconclusive. BIS/BAS may interact with adolescent trait characteristics, resulting in different outcomes. Grit may alter adolescents' motivations, which can even be based on biological systems such as BIS/BAS. However, the impact of BIS/BAS and potential moderating factors on adolescents' internet use remains unclear. This study aimed to examine the association between BIS/BAS and IA in adolescents and explore the potential moderating roles of the two facts of grit, passion and perseverance, on the association between BIS/BAS and IA.

Methods

A total of 1,881 junior and senior high school students (M_age = 14.65, standard deviation _age = 1.81, ranging from 11 to 20 years) completed a self-reported measure of BIS/BAS, IA, and grit. Independent t-tests and chi-square tests were used to evaluate the differences between adolescents with IA and those with normal internet use. Pearson correlation and regression model analyses, including moderating model analysis, were used to qualify the associations between IA and BIS/BAS, as well as the potential moderating role of grit passion and perseverance.

Results

The results showed that 19.1% of the participants met the criteria for IA. Both BIS (β = 0.085, t = 3.650, p < 0.001) and BAS (β = 0.06, t = 2.552, p < 0.05) were positively associated with IA risk, and grit-perseverance moderated the association between BIS and IA (β = -0.230, bootstrap 95% confidence interval: -0.450 to -0.012) and BAS with IA (β = -0.187, bootstrap 95% confidence interval: -0.299 to -0.076).

Conclusion

These findings extend the current knowledge on the associations between BIS/BAS and IA. Moreover, the findings suggest that enhancing grit-perseverance may improve prevention and intervention of IA risk in adolescents who are sensitive to BIS and BAS.

A Network Analysis of the Relationships Between Behavioral Inhibition/Activation Systems and Problematic Mobile Phone Use

Background

It is of great concern to society that individuals can be vulnerable to problematic mobile phone use (PMPU). However, there are a few studies in the field evaluating associations between behavioral inhibition/activation systems (BIS/BAS) and PMPU, and the results have been inconsistent. This study aimed to explore the relationships between BIS/BAS and PMPU by network analysis.

Methods

A total of 891 young adults participated in the study. BIS/BAS and PMPU were assessed by using the behavioral inhibition and activation systems scale and smartphone application-based addiction scale, respectively. The structure of the BIS/BAS-PMPU network was characterized using "strength," "closeness" and "betweenness" as centrality indices. Edge-weight accuracy and centrality stability were tested using a bootstrap procedure.

Results

The network analysis showed that "mood modification," "tolerance" and "withdrawal symptoms" had high centrality. In addition, the positive connection between BIS and "mood modification" or "tolerance" and between BAS-fun seeking and "mood modification" or "conflict" were also shown in the BIS/BAS-PMPU network.

Conclusion

These findings shed light on the central and bridge components between the BIS/BAS and PMPU communities, providing new evidence relevant to potential mechanisms that account for how high-BIS or high-BAS individuals develop PMPU, and inspiring component-based PMPU prevention or interventions.

Harm avoidance, daily stress, and problematic smartphone use in children and adolescents

OBJECTIVE

Temperament is close to susceptibility to stress and the increased level of stress may lead problematic smartphone use (PSU). In this study, the relationships between harm avoidance (HA) as a personality trait, daily traits, and PSU in children and adolescents were investigated.

METHODS

At baseline, all participants (184 children and adolescents, mean age 13.15 years) completed questionnaires on PSU using the Smartphone Addiction Scale-Short Version (SAS-SV) and the Korean Smartphone Addiction Proneness Scale (SAPS). The Daily Hassles Questionnaire (DHQ) and Junior Temperament and Character Inventory (JTCI) were also administered to evaluate stress levels and personality traits. SAS-SV, SAPS, and DHQ were reassessed at 3 and 6 months.

RESULTS

Among JTCI temperament, HA displayed robust positive correlations with SAS-SV, SAPS, and DHQ at all time points. Mediation effects of daily stress on the relationship between HA and PSU were observed at baseline, 3, and 6 months.

CONCLUSION

The findings suggest that managing stress may important in PSU children and adolescents with high HA.

Differences in Reward Sensitivity between High and Low Problematic Smartphone Use Adolescents: An ERP Study

Background: Problematic smartphone use is highly prevalent in adolescent populations compared to other age groups (e.g., adults and young children). Previous studies suggested that higher levels of reward sensitivity were associated with problematic smartphone use. Therefore, the current study investigated the neural processing of monetary and social reward and punishment feedbacks between high and low problematic smartphone use adolescents. Methods: 46 adolescents participated in the current study and they were categorized into two groups based on their level of problematic smartphone use: those who obtained low scores on the measure of problematic smartphone use were categorized as Low Problematic Smartphone Use (LPSU), and those who obtained high scores on the measure of problematic smartphone use were categorized as High Problematic Smartphone Use (HPSU). Electrocortical activities were recorded during the processing of monetary and social reward and punishment feedback. Results: (1) LPSUs evoked larger P3 in the social punishment condition than in the monetary punishment condition. HPSUs evoked larger P3 in the social reward condition than in the monetary condition. (2) The feedback-related negativity (FRN) amplitudes in the reward condition were significantly larger than those in the punishment condition. (3) HPSUs induced larger reward positivity in social feedback conditions than in monetary feedback conditions, while there were no significant differences between the two types of conditions in the LPSUs. Discussion: The results provide neural underpinning evidence that high sensitivity to social rewards may be related to problematic smartphone use in adolescence.

Reciprocal Prediction between Impulsivity and Problematic Internet Use among North Korean Refugee Youths in South Korea by Gender and Adverse Childhood Experience

OBJECTIVE

North Korean refugee youths are at higher risk of developing a wide array of psychosocial sequelae, including increased impulsivity and problematic internet use. We aimed to identify reciprocal temporal relationships by performing autoregressive cross-lagged modeling and to examine how these relations differ by gender and adverse childhood experience.

METHODS

We used the follow-up data of 108 North Korean refugee youths in South Korea over a 1-year period. The Barratt Impulsivity Scale-Brief and Young's Internet Addiction Test were used to assess impulsivity and problematic internet use, respectively.

RESULTS

Autoregressive effects were significant across all groups, indicating that impulsivity and problematic internet use were stable across time; however, prospective prediction of problematic internet use from impulsivity was not significant across all groups. Problematic internet use at baseline positively predicted impulsivity at after 1 year of follow up in only males and individuals with adverse childhood experience.

CONCLUSION

Our findings suggest that the negative effect of problematic internet use (i.e., increased impulsivity) among North Korean refugee youths may be more profound in males and those with adverse childhood experience. We present possible explanations for these findings and discuss the implications for targeted interventions.

Relationships between morningness, Big Five personality traits, and problematic Internet use in young adult university students: mediating role of depression

The aim of this study was twofold. Firstly, it explored the relationships between morningness, Big Five personality traits, depression, and problematic Internet use (PIU). Secondly, it examined the possible mediating role of depression in these relationships. The following measures were used: the Internet Addiction Test, the Composite Scale of Morningness, the International Personality Item Pool-Big Five Markers-20, and the Center for Epidemiologic Studies Depression Scale. The participants in the study were 398 university students 18 to 30 (M = 20.37, SD = 2.29) years of age. The study found that PIU Total, PIU Mental Disorder, and PIU Time Management Disorder are positively related to depression and negatively related to morningness, Extraversion, Agreeableness, Conscientiousness, Emotional Stability, and Openness. PIU was more often found in individuals with an evening chronotype. The study confirmed the role of depression as a mediator in the relationship of personality traits and morningness to PIU Mental Disorder and PIU Time Management Disorder. For PIU Mental Disorder, the study revealed a full mediation effect of depression in the case of morningness, Emotional Stability, and Extraversion, and partial mediation in the case of Agreeableness and Intellect. For PIU Time Management Disorder, there was a full mediation effect of depression in the case of Emotional Stability, Extraversion, and Agreeableness, and partial mediation in the case of morningness and Intellect. The results highlight the importance of including depression when investigating the relationship between morningness and personality in studies of PIU.

Technology Use: Too Much of a Good Thing?

There is growing evidence of risks associated with excessive technology use, especially among teens and young adults. However, little is known about the characteristics of those who are at elevated risk of being problematic users. Using data from the 2012 Current Population Survey Internet Use Supplement and Educational Supplement for teens and young adults, this study developed a conceptual framework for modeling technology use. A three-part categorization of use was posited for utilitarian, social and entertainment purposes, which fit observed data well in confirmatory factor analysis. Seemingly unrelated regression was used to examine the demographic characteristics associated with each of the three categories of use. Exploratory factor analysis uncovered five distinct types of users, including one user type that was hypothesized to likely be at elevated risk of problematic use. Regression results indicated that females in their twenties who are in school and have greater access to technology were most likely to fall into this higher-risk category. Young people who live with both parents were less likely to belong to this category. This study highlighted the importance of constructing models that facilitate identification of patterns of use that may characterize a subset of users at high risk of problematic use. The findings can be applied to other contexts to inform policies related to technology and society as well.

SUPPLEMENTARY INFORMATION

The online version of this article (10.1007/s11293-020-09683-1) contains supplementary material, which is available to authorized users.

Associations of personality and clinical characteristics with excessive Internet and smartphone use in adolescents: A structural equation modeling approach

Adolescent Internet addiction is an important social issue entailing extensive use of Internet and smartphones and its side effects. This study identified relevant psychological factors that affect excessive Internet use (EIU) and excessive smartphone use (ESU) in adolescents using structural equation modeling (SEM). A sample of 714 individuals drawn from lists of middle school students in South Korea completed self-administered questionnaires, including Young's Internet Addiction Test (Y-IAT), the Smartphone Addiction Scale (SAS), and various clinical and psychological scales measuring depression, anxiety, attention deficit/hyperactivity disorder (ADHD), aggression, expression of anger, and the behavioral inhibition system (BIS)/activation system (BAS). The final model, fitted using SEM, showed that both clinical characteristics, including ADHD symptoms, aggression, expression of anger, depression, and anxiety, and personality characteristics, represented by BIS/BAS, played important roles in the severity of EIU or ESU. In particular, affective components such as depression and anxiety were significantly associated with both EIU and ESU, whereas aggression, the expression of anger, and ADHD symptoms affected only EIU. Furthermore, the association between ESU and EIU was significant. Although personality characteristics measured by the BIS and BAS scores did not have direct effects on addiction, they were associated with clinical features and might be risk factors for addiction. The model revealed significant pathways from personality and clinical features to EIU and ESU in adolescents and informed our basic understanding of the meaningful predictors of these addictions and their direct and indirect influences.

Gray matter volumetric correlates of behavioral activation and inhibition system traits in children: An exploratory voxel-based morphometry study of the ABCD project data

Approach and avoidance represent two fundamental behavioral traits that develop early in life. Previous studies have examined the neural correlates of approach and avoidance traits in adults and adolescents. Here, using the data set of the Adolescent Brain Cognition Development project, we investigated the structural cerebral bases of behavioral activation system (BAS) and behavioral inhibition system (BIS) in children. We employed voxel-based morphometry to examine how gray matter volumes (GMV) related specifically to BAS and BIS traits in 11,542 children (5491 girls, age 9-10 years) with 648 and 2697 identified as monozygotic twins (MZ) and dizygotic twins/siblings (DZ), respectively. After accounting for the BIS score, higher BAS scores (residuals) were positively correlated with the GMV of the ventral striatum (VS), and the correlation was stronger in MZ than in DZ and unrelated children, with a heritability (h²) of 0.8463. Higher BAS scores were negatively correlated with the GMV of bilateral visual, lateral orbitofrontal, temporal, and inferior frontal cortex, as well as the precuneus. Higher BIS (after accounting for BAS) scores were negatively correlated with the GMVs of the ventral caudate and bilateral putamen/pallidum, hypothalamus, and right anterior insula, and the correlation was stronger in MZ than in DZ and unrelated children, with a heritability of 0.8848. A cluster in the VS showed positive and negative correlation with the BAS and BIS scores, respectively. These findings suggest shared and distinct cerebral volumetric bases of the BAS and BIS traits in children. Whereas both traits have a strong genetic basis, the BAS relative to BIS appears to be more amenable to environmental influences. These findings add to the literature of developmental neuroscience and may help identify genetic risk factors of externalizing and internalizing psychopathology.

Unpacking Associations between Mood Symptoms and Screen Time in Preadolescents: a Network Analysis

Mounting evidence highlights the link between screen time and adolescent mood problems. However, there are several shortcomings to the extant literature: (1) this link is underexplored in preadolescents, (2) most existing studies look at mood problems using categorical diagnoses rather than from a symptom-level perspective, despite the heterogeneity within mood disorders, (3) few studies have simultaneously examined the links of mood symptoms with different types of screen time, and (4) family/child-level factors that have shown links to youth psychopathology are not typically considered. This study, for the first time, examined the relationships of mood symptoms with different types of screen time, while accounting for theoretically important factors-parental monitoring and the behavioral inhibition/activation systems (BIS/BAS)-in preadolescents aged 9 to 10 from 9986 families participating in the Adolescent Brain and Cognitive Development Study. Using mixed graphical models, we found that screen time involving age-inappropriate content was stably and significantly associated with various elevated mood symptoms, independent from other types of screen time, BIS/BAS, and parental monitoring. Additionally, age-inappropriate screen time was associated with increased overall symptom connectivity. Further, preadolescents engaged in high levels of age-inappropriate screen time reported different symptom profiles (i.e., differences in symptom centralities) from common pediatric mood problems. Our findings underline the multifaceted role (i.e., direct associations with symptoms, a moderator for symptom relationships, associations with distinct symptom profiles) of age-inappropriate screen time in preadolescent mood problems. These findings serve as foundations for future research that may facilitate early detection of preadolescents at risk of mood problems.

Self-Efficacy and Clinical Characteristics in Casual Gamers Compared to Excessive Gaming Users and Non-Gamers in Young Adults

This study investigated differences in the self-efficacy and clinical characteristics which were found relevant to addictive behaviors in young adults according to time spent gaming. To our knowledge, this is the first study to explore self-efficacy in casual gamers relative to patients with internet gaming disorder (IGD) and non-gamers. In total, 158 young adults participated in this study and were divided into three groups: excessive gamers, who were diagnosed with IGD based on the Diagnostic and Statistical Manual of Mental Disorder-fifth edition (DSM-5, n = 71); casual gamers, who played games regularly but did not meet the criteria for IGD (n = 37); and non-gamers/controls, who did not engage in gaming (n = 50). All participants completed self-administered questionnaires, including measures of self-efficacy and clinical features such as the Barratt Impulsiveness Scale, Beck Depression Inventory, Beck Anxiety Inventory, Behavioral Activation/Inhibition Systems, aggression, and psychosocial well-being. There were significant differences in the self-efficacy according to the extent of gaming (excessive gamers < casual gamers < non-gamers). In addition, aggression, impulsivity, depression, anxiety, level of stress, and behavioral inhibition system scores were significantly higher in excessive gamers than in casual gamers and non-gamers. These findings showed that individuals who spend more time playing games tend to have lower self-efficacy. Our study suggests that self-efficacy may protect against or constitute a risk of excessive gaming, particularly among casual gamers. It is necessary to pay attention to enhancing psychological well-being through self-efficacy to prevent addiction in young adult gamers.

Investigation of Correlated Internet and Smartphone Addiction in Adolescents: Copula Regression Analysis

Internet and smartphone addiction have become important social issues. Various studies have demonstrated their association with clinical and psychological factors, including depression, anxiety, aggression, anger expression, and behavioral inhibition, and behavioral activation systems. However, these two addictions are also highly correlated with each other, so the consideration of the relationship between internet and smartphone addiction can enhance the analysis. In this study, we considered the copula regression model to regress the bivariate addictions on clinical and psychological factors. Real data analysis with 555 students (age range: 14-15 years; males, N = 295; females, N = 265) from South Korean public middle schools is illustrated. By fitting the copula regression model, we investigated the dependency between internet and smartphone addiction and determined the risk factors associated with the two addictions. Furthermore, by comparing the model fits of the copula model with linear regression and generalized linear models, the best copula model was proposed in terms of goodness of fit. Our findings revealed that internet and smartphone addiction are not separate problems, and that associations between them should be considered. Psychological factors, such as anxiety, the behavioral inhibition system, and aggression were also significantly associated with both addictions, while ADHD symptoms were related to internet addiction only. We emphasize the need to establish policies on the prevention, management, and education of addiction.

Maladaptive neurovisceral interactions in patients with Internet gaming disorder: A study of heart rate variability and functional neural connectivity using the graph theory approach

Heart rate variability (HRV) can be used to represent the regulatory adaptive system and is a proxy for neurovisceral integration. Consistent with the view that, like other addictions, Internet gaming disorder (IGD) involves disrupted regulatory function, the present study hypothesized that IGD patients would show (a) decreased HRV, (b) ineffective functional neural connectivity, and (c) differential patterns of association between HRV and functional neural connectivity relative to healthy controls (HCs). The present study included 111 young adults (53 IGD patients and 58 age‐ and sex‐matched HCs) who underwent simultaneous recordings with an electrocardiogram and electroencephalogram during a resting state. Heart rate (HR), HRV, and functional neural connectivity were calculated using the graph theory approach. Compared with the HCs, the IGD patients exhibited elevated HR and decreased HRV based on the high frequency (HF), which reflects suppression of parasympathetic and/or vagal tone. The IGD patients also exhibited a heightened theta band characteristic path length (CPL) compared with HCs, indicating decreased efficacy of the functional network. Furthermore, IGD patients exhibited negative correlations between the standard deviation of the normal‐to‐normal interval index (SDNNi) and theta and delta CPL values, which were not observed in HCs. In conclusion, the present findings suggest that IGD patients might have maladaptive brain‐body integration features involving disruptions of the autonomic nervous system and brain function.

Reinforcement sensitivity, depression and anxiety: A meta-analysis and meta-analytic structural equation model

Reinforcement Sensitivity Theory (RST) posits that individual differences in reward and punishment processing predict differences in cognition, behavior, and psychopathology. We performed a quantitative review of the relationships between reinforcement sensitivity, depression and anxiety, in two separate sets of analyses. First, we reviewed 204 studies that reported either correlations between reinforcement sensitivity and self-reported symptom severity or differences in reinforcement sensitivity between diagnosed and healthy participants, yielding 483 effect sizes. Both depression (Hedges' g = .99) and anxiety (g = 1.21) were found to be high on punishment sensitivity. Reward sensitivity negatively predicted only depressive disorders (g = -.21). More severe clinical states (e.g., acute vs remission) predicted larger effect sizes for depression but not anxiety. Next, we reviewed an additional 39 studies that reported correlations between reinforcement sensitivity and both depression and anxiety, yielding 156 effect sizes. We then performed meta-analytic structural equation modeling to simultaneously estimate all covariances and control for comorbidity. Again we found punishment sensitivity to predict depression (β = .37) and anxiety (β = .35), with reward sensitivity only predicting depression (β = -.07). The transdiagnostic role of punishment sensitivity and the discriminatory role of reward sensitivity support a hierarchical approach to RST and psychopathology.

The Relationship Between Behavioral Inhibition and Behavioral Activation Systems, Impulsiveness, and Internet Gaming Disorder Among Students of Different Ages

Background and Aims: Internet Gaming Disorder (IGD), which is an underlying symptom classified as a behavioral addiction disorder, has many related social problems that have garnered the bulk of attention in recent research. However, its psychological/behavioral mechanism is still unclear. The purpose of the current study was to explore the relationship between IGD and impulsivity which is regulated by behavioral inhibition and activation among different age groups. Methods: A total of 1,525 students completed Young's Internet Addiction Test (IAT), Online Game Addiction Questionnaire, the Behavioral Inhibition System/Behavioral Activation System (BIS/BAS) scales, and the Barratt Impulsiveness Scale-11 (BIS-11). Results: (1) The prevalence of IGD in different ages students was 10.3%. (2) BIS, BAS-Fun seeking (BAS-F), and BIS-11 scores indicated that there were significant differences between IGD and non-IGD individuals. (3) BIS showed significant differences in different grades (i.e., between undergraduates and middle school students with IGD; F = 3.10, p < 0.05). (4) The IAT scores demonstrated a significant positive correlation with BIS scores (r = 0.375, p < 0.05) among undergraduates with IGD; IAT scores of high school students with IGD were negatively correlated with BAS-Reward (BAS-R) (r = -0.28, p < 0.05).5)BIS and BIS-11 together could explain 14.9% variance of IGD among the college group; BAS-R and BAS-F together could explain 16.7% variance of IGD among the high school group (p < 0.05). Conclusions: The relationships between IGD and BIS, BAS-F, BAS-D, BIS-11 scores differed due to the age group of individuals tested.

The Mediating Role of Coping Styles on Impulsivity, Behavioral Inhibition/Approach System, and Internet Addiction in Adolescents From a Gender Perspective

Previous findings have shown that impulsivity and Behavioral Inhibition/Approach System (BIS/BAS) have substantial effects on adolescents’ Internet addiction, but the mechanisms underlying these associations and gender differences in these effects have received little attention. We examined the mediating effects of coping styles from impulsivity, and BIS/BAS to Internet addiction as well as gender differences in these associations. A total of 416 Chinese adolescents were examined using a cross-sectional survey involving Young’s Diagnostic Questionnaire for Internet Addiction, Barratt Impulsiveness Scale, BIS/BAS scales, and Coping Style Scale for Middle School Students. The data were analyzed using the independent sample t-test, chi-square test, Pearson correlation, and structure equation modeling. The results from the multiple-group (by adolescent gender) structural model analysis revealed that both impulsivity (p < 0.001) and BIS (p = 0.001) directly predicted positive Internet addiction in girls, while both impulsivity (p = 0.011) and BAS (p = 0.048) directly predicted positive Internet addiction in boys. Furthermore, emotion-focused coping mediated the relationship between impulsivity and Internet addiction (β = 0.080, 95% CI: 0.023–0.168) and the relationship between BIS and Internet addiction (β = 0.064, 95% CI: 0.013–0.153) in girls, while in boys, problem-focused coping and emotion-focused coping mediated the association between impulsivity and Internet addiction (β = 0.118, 95% CI: 0.031–0.251; β = 0.065, 95% CI: 0.010–0.160, respectively) and problem-focused coping mediated the association between BAS and Internet addiction [β = −0.058, 95% CI: (−0.142)–(−0.003)]. These findings extend our insight into the mechanisms underlying the associations among impulsivity, BIS/BAS, and Internet addiction in adolescents and suggest that gender-sensitive training approaches to decrease adolescents’ Internet addiction are indispensable. These interventions should focus on the different gender predictors of adolescent Internet addiction and on the development of specific coping styles for boys and girls respectively.

Dysfunctional cognitive control and reward processing in adolescents with Internet gaming disorder

Developmental theories posit that immature cognitive control and excessive reward-seeking capacities may be a risk factor for addictive behaviors during adolescence, but the control and reward capacities have rarely been assessed experimentally in adolescents with Internet gaming disorder (IGD) simultaneously. This electrophysiological study examined inhibitory control and reward processing in adolescents with IGD during a go/no-go task and a gambling task. Behaviorally, the adolescents with IGD exhibited lower inhibitory control, as measured by the accuracy of no-go trials, and more risk seeking, as measured by the proportion of risky choices, than did the controls. Compared with the controls, the adolescents with IGD exhibited decreased no-go P3 and blunted feedback-related negativity (FRN) amplitudes following gains (gain FRN) but not losses. Thus, IGD in adolescents is potentially driven by dysfunction of the control system and the approach system rather than the avoidance system, supporting the neurobiological model of adolescent development.

The Relationship Between Personality Traits, Psychopathological Symptoms, and Problematic Internet Use: A Complex Mediation Model

BACKGROUND

There are many empirical studies that demonstrate the associations between problematic internet use, psychopathological symptoms, and personality traits. However, complex models are scarce.

OBJECTIVE

The aim of this study was to build and test a mediation model based on problematic internet use, psychopathological symptoms, and personality traits.

METHODS

Data were collected from a medical addiction center (43 internet addicts) and internet cafés (222 customers) in Beijing (mean age 22.45, SD 4.96 years; 239/265, 90.2% males). Path analysis was applied to test the mediation models using structural equation modeling.

RESULTS

Based on the preliminary analyses (correlations and linear regression), two different models were built. In the first model, low conscientiousness and depression had a direct significant influence on problematic internet use. The indirect effect of conscientiousness-via depression-was nonsignificant. Emotional stability only affected problematic internet use indirectly, via depressive symptoms. In the second model, low conscientiousness also had a direct influence on problematic internet use, whereas the indirect path via the Global Severity Index was again nonsignificant. Emotional stability impacted problematic internet use indirectly via the Global Severity Index, whereas it had no direct effect on it, as in the first model.

CONCLUSIONS

Personality traits (ie, conscientiousness as a protective factor and neuroticism as a risk factor) play a significant role in problematic internet use, both directly and indirectly (via distress level).

The Role of Resilience in Internet Addiction among Adolescents between Sexes: A Moderated Mediation Model

The behavioral inhibition/activation systems (BIS/BAS) have been considered to be predictors of Internet addiction, mediated by clinical variables such as anxiety and depression. However, resilience has been suggested as a protective factor toward Internet addiction, and certain sex differences in resilience buffering the effects of vulnerability have been reported. Thus, the aim of this study was to identify any role of resilience that might moderate the effects of BIS/BAS on Internet addiction through multiple clinical variables in boys and girls. A total of 519 middle-school students (268 boys and 251 girls, all 14 years old) were administered a questionnaire battery that measures Internet addiction, BIS/BAS, depression, anxiety, impulsivity, anger, and resilience. We used the PROCESS macro in SPSS to perform moderation and mediation analysis. Findings revealed that although a somewhat similar mediation model was supported in both sexes, moderating effects of resilience only emerged in girls. The results showed a protective role of resilience differing between sexes. These results suggest that clinicians should consider sex in the way resilience works as a protective factor against Internet addiction and focus on mitigating the effects of vulnerability by enhancing resilience in female Internet addicts.

Evidences from Rewarding System, FRN and P300 Effect in Internet-Addiction in Young People SHORT TITLE: Rewarding System and EEG in Internet-Addiction

The present research explored rewarding bias and attentional deficits in Internet addiction (IA) based on the IAT (Internet Addiction Test) construct, during an attentional inhibitory task (Go/NoGo task). Event-related Potentials (ERPs) effects (Feedback Related Negativity (FRN) and P300) were monitored in concomitance with Behavioral Activation System (BAS) modulation. High-IAT young participants showed specific responses to IA-related cues (videos representing online gambling and videogames) in terms of cognitive performance (decreased Response Times, RTs; and Error Rates, ERs) and ERPs modulation (decreased FRN and increased P300). Consistent reward and attentional biases was adduced to explain the cognitive "gain" effect and the anomalous response in terms of both feedback behavior (FRN) and attentional (P300) mechanisms in high-IAT. In addition, BAS and BAS-Reward subscales measures were correlated with both IAT and ERPs variations. Therefore, high sensitivity to IAT may be considered as a marker of dysfunctional reward processing (reduction of monitoring) and cognitive control (higher attentional values) for specific IA-related cues. More generally, a direct relationship among reward-related behavior, Internet addiction and BAS attitude was suggested.

Comparative study of the effects of bupropion and escitalopram on Internet gaming disorder

AIM

We compared the efficacy of bupropion and escitalopram treatments in Internet gaming disorder (IGD) patients.

METHODS

We recruited 119 adolescents and adults with IGD. We treated these participants for 6 weeks in three groups as follows: 44 participants were treated with bupropion SR (bupropion group), 42 participants were treated with escitalopram (escitalopram group), and 33 patients without any medication were observed in the community (observation group). At baseline and at the 6-week follow-up visit, all subjects were evaluated using the Clinical Global Impression-Severity Scale, the Young Internet Addiction Scale, the Beck Depression Inventory, the ADHD Rating Scale, and the Behavioral Inhibition and Activation Scales.

RESULTS

Both the escitalopram group and the bupropion group showed improvement on all clinical symptom scales after 6 weeks of treatment compared to the observation group. Additionally, the bupropion group showed greater improvement on scores for the Clinical Global Impression-Severity Scale, the Young Internet Addiction Scale, the ADHD Rating Scale, and the Behavioral Inhibition Scale than the escitalopram group.

CONCLUSION

Both bupropion and escitalopram were effective in treating and managing IGD symptoms. Moreover, bupropion appeared to be more effective than escitalopram in improving attention and impulsivity in IGD patients. In addition, attention and impulsivity seem to be important for the management of IGD.

The association of Internet addiction symptoms with impulsiveness, loneliness, novelty seeking and behavioral inhibition system among adults with attention-deficit/hyperactivity disorder (ADHD)

The aims of this study were to test the associations of the Internet addiction symptoms with impulsiveness, loneliness, novelty seeking and behavioral inhibition systems among adults with attention-deficit/hyperactivity disorder (ADHD) and adults with non-ADHD. A total of 146 adults aged between 19 and 33 years involved in this study. Participants were assessed with the Chinese version of the adult ADHD Self-report scale (ASRS), the Revised Chen Internet Addiction Scale (CIAS-R), the Barratt Impulsiveness Scale 11 (BIS-11), the Tridimensional Personality Questionnaire (TPQ), the UCLA loneliness scale, and the Behavioral Inhibition System and Behavioral Activation System Scale (BIS/BAS Scale). The results of hierarchical regression analysis indicated that impulsiveness, loneliness, and behavioral inhibition system were significant predictors of Internet addition among adults with ADHD. Higher loneliness was significantly associated with more severe Internet addition symptoms among the non-ADHD group. Adults with high impulsiveness, loneliness, and BIS should be treated with caution for preventing Internet addiction. In addition, adults with and without ADHD should be provided with different preventative strategies.

Challenges in Internet Addiction Disorder: Is a Diagnosis Feasible or Not?

An important international discussion began because of some pioneer studies carried out by Young (a) on the internet addiction disorder (IAD). In the fifth and most recent version of the Diagnostic, and Statistical Manual of Mental Disorders (DSM) there is no mention of this disorder and among researchers there are basically two opposite positions. Those who are in favor of a specific diagnosis and those who are claiming the importance of specific criteria characterizing this behavior and the precise role it has in the patient’s life. The aim of the present paper is to answer the question whether it is possible or not to formulate diagnoses of internet-related disorders. We revised literature on the history of diagnostic criteria, on neurocognitive evidence, on the topic debate and on IAD instrumental measures. We found that the disorder was not univocally defined and that the construct was somehow too broad and generic to be explicative for a diagnosis. Indeed, the models are borrowed from other addiction pathologies and they are often formulated before the development of internet as intended in current society. In conclusion, we think we need a more innovative, integrated and comprehensive model for an IAD diagnosis.

The Relationship Between Hypersexual Behavior, Sexual Excitation, Sexual Inhibition, and Personality Traits

The term hypersexuality was introduced to describe excessive sexual behavior associated with a person's inability to control his or her sexual behavior. The main aim of the present study was to investigate the impact of different personality traits on the degree of hypersexual behavior as measured by the Hypersexual Behavior Inventory (HBI). A further aim was to evaluate the association between sexual inhibition and excitation [as described in the Dual Control Model (DCM)] and hypersexual behavior. A sample of 1,749 participants completed an internet-based survey comprised the HBI, the short form of the Sexual Inhibition/Sexual Excitation Scales (SIS/SES-SF) as well as more general personality measures: the Behavioral Inhibition System/Behavioral Activation System-scales (BIS/BAS-scales) and a short version of the Big Five Inventory (BFI-10). Using the recommended HBI cut-off, 6.0 % (n = 105) of the present sample could be categorized as hypersexual, which is comparable to the results of previous studies about the prevalence of hypersexual behavior in the general population. The results provided strong support for the components of the DCM-sexual excitation and inhibition-to explain hypersexual behavior, irrespective of gender and sexual orientation. Some of the general personality traits also showed significant relationships with hypersexual behavior. Taken together, the results of the present study provide further support for the relevance of research about the relationships between sexual problems and disorders, the DCM, and personality variables.

Association of stress coping strategies with Internet addiction in college students: The moderating effect of depression

BACKGROUND

This study examined the association between stress-related coping strategies and Internet addiction and the moderating effect of depression in a sample of Taiwanese college students.

METHOD

A total of 500 college students (238 men and 262 women) participated in this study. Internet addiction was assessed using the Chen Internet Addiction Scale. Participants' stress coping strategies and depressive symptoms were measured using the Coping Orientation to Problems Experienced and the Beck Depression Inventory-II, respectively. We used t and chi-square tests to examine differences in demographic characteristics, depression, and stress coping strategies between participants with and without Internet addiction. Significant variables were used in a logistic regression model to examine the association between stress coping strategies and Internet addiction and the moderating effect of depression on the association.

RESULTS

Results indicated that use of restraint coping was negatively associated with Internet addiction (odds ratio [OR]=0.886, 95% confidence interval [CI]: 0.802-0.977), whereas denial (OR=1.177, 95% CI: 1.029-1.346) and mental disengagement (OR=2.673, 95% CI: 1.499-4.767) were positively associated with Internet addiction. Depression had a moderating effect on the association between denial and Internet addiction (OR=0.701, 95% CI: 0.530-0.927).

CONCLUSIONS

Stress coping strategies and depression are important factors to evaluate when developing intervention programs targeting college undergraduate students with Internet addiction.

Hooked on Facebook: The Role of Social Anxiety and Need for Social Assurance in Problematic Use of Facebook

There is a growing concern that excessive and uncontrolled use of Facebook not only interferes with performance at school or work but also poses threats to physical and psychological well-being. The present research investigated how two individual difference variables--social anxiety and need for social assurance--affect problematic use of Facebook. Drawing on the basic premises of the social skill model of problematic Internet use, we hypothesized that social anxiety and need for social assurance would be positively correlated with problematic use of Facebook. Furthermore, it was predicted that need for social assurance would moderate the relationship between social anxiety and problematic use. A cross-sectional online survey was conducted with a college student sample in the United States (N=243) to test the proposed hypotheses. Results showed that both social anxiety and need for social assurance had a significant positive association with problematic use of Facebook. More importantly, the data demonstrated that need for social assurance served as a significant moderator of the relationship between social anxiety and problematic Facebook use. The positive association between social anxiety and problematic Facebook use was significant only for Facebook users with medium to high levels of need for social assurance but not for those with a low level of need for social assurance. Theoretical and practical implications of these findings were discussed.

Is problematic internet use an indicator of eating disorders among Turkish university students?

AIMS

The aim of this study was to investigate the relationship between problematic internet use and eating attitudes in a group of university students.

METHODS

The study sample consisted of 314 students attending programs at the faculties of education, medicine and communications at the Karadeniz Technical University in Turkey. One hundred forty-seven (46.8 %) were male and 167 (53.2 %) female. The Problematic Internet Use Scale was used to measure problematic internet use levels among university students and the Eating Attitudes Test to determine anorexia nervosa symptoms. Additionally, a Personal Data Form was used to determine age, gender, faculty attended and computer ownership. Data were analyzed on SPSS 15.00. Pearson's product moments correlation coefficient, multiple linear regression analysis, the independent t test and one-way ANOVA were used for data analysis.

RESULTS

The research findings showed that 46.8 % of students were female and 53.2 % male. Mean age was 20.65 (SD 1.42). Analysis showed a significant positive correlation between problematic internet use and eating attitudes (r = 0.77, p < 0.01). Problematic internet use was found to be a significant predictor of eating attitudes. The results also showed a significant difference in problematic internet use with regard to program variables [F (2,311) = 102.79]. There were no significant differences in problematic internet use in terms of gender or computer ownership.

CONCLUSIONS

The results of this study indicate that problematic internet use is significantly correlated with eating disorders, that problematic internet use does not vary on the basis of gender or computer ownership and that variations arise in problematic internet use depending on the faculty attended.

Are adolescents with internet addiction prone to aggressive behavior? The mediating effect of clinical comorbidities on the predictability of aggression in adolescents with internet addiction

Previous studies have reported associations between aggression and Internet addiction disorder (IAD), which has also been linked with anxiety, depression, and impulsiveness. However, the causal relationship between aggression and IAD has thus far not been clearly demonstrated. This study was designed to (a) examine the association between aggression and IAD and (b) investigate the mediating effects of anxiety, depression, and impulsivity in cases in which IAD predicts aggression or aggression predicts IAD. A total of 714 middle school students in Seoul, South Korea, were asked to provide demographic information and complete the Young's Internet Addiction Test (Y-IAT), the Buss-Perry Aggression Questionnaire, the Barratt Impulsiveness Scale-11, the State-Trait Anger Expression Inventory-2, the Beck Anxiety Inventory, the Beck Depression Inventory, and the Conners-Wells Adolescent Self-Report Scale. Three groups were identified based on the Y-IAT: the usual user group (n=487, 68.2%), the high-risk group (n=191, 26.8%), and the Internet addiction group (n=13, 1.8%). The data revealed a linear association between aggression and IAD such that one variable could be predicted by the other. According to the path analysis, the clinical scales (BAI, BDI, and CASS) had partial or full mediating effects on the ability of aggression to predict IAD, but the clinical scales had no mediating effect on the ability of IAD to predict aggression. The current findings suggest that adolescents with IAD seem to have more aggressive dispositions than do normal adolescents. If more aggressive individuals are clinically prone to Internet addiction, early psychiatric intervention may contribute to the prevention of IAD.

Internet Addiction in Young People

In our technology-savvy population, mental health professionals are seeing an increasing trend of excessive Internet use or Internet addiction. Researchers in China, Taiwan and Korea have done extensive research in the field of Internet addiction. Screening instruments are available to identify the presence of Internet addiction and its extent. Internet addiction is frequently associated with mental illnesses such as anxiety, depression, conduct disorder and attention deficit hyperactivity disorder (ADHD). Treatment modalities include individual and group therapies, cognitive behavioural therapy (CBT), family therapy and psychotropic medications. A significant proportion of Singapore adolescents engaging in excessive Internet use are also diagnosed to have concomitant Internet addiction. Despite the presence of a variety of treatment options, future research in this area is needed to address its growing trend and to minimise its negative psychological and social impact on the individuals and their families. Key words: Aetiology, Pathophysiology, Treatment

Dysfunctional inhibitory control and impulsivity in Internet addiction

The purpose of this study was to explore a psychological profile of Internet addiction (IA) considering impulsivity as a key personality trait and as a key component of neuropsychological functioning. Twenty three subjects with IA (Young's Internet Addiction Test scores=70 or more) and 24 sex-, age-, and intelligence-matched healthy controls were enrolled. Participants filled out a questionnaire about trait impulsivity, the Trait Characteristic Inventory, depression, and anxiety. Next, we administered traditional neuropsychological tests including the Stroop et al. and computerized neuropsychological tests using the Cambridge Neuropsychological Test Automated Battery. The IA group exhibited more trait impulsivity than the healthy control group. They also scored higher for novelty seeking and harm avoidance. The IA group performed more poorly than the healthy control group in a computerized stop signal test, a test for inhibitory function and impulsivity; no group differences appeared for other neuropsychological tests. The IA group also scored higher for depression and anxiety, and lower for self-directedness and cooperativeness. In conclusion, individuals with IA exhibited impulsivity as a core personality trait and in their neuropsychological functioning.

Effects of reward sensitivity and regional brain volumes on substance use initiation in adolescence

This longitudinal study examines associations between baseline individual differences and developmental changes in reward [i.e. behavioral approach system (BAS)] sensitivity and relevant brain structures' volumes to prospective substance use initiation during adolescence. A community sample of adolescents ages 15-18 with no prior substance use was assessed for substance use initiation (i.e. initiation of regular alcohol use and/or any use of other substances) during a 2-year follow-up period and for alcohol use frequency in the last year of the follow-up. Longitudinal 'increases' in BAS sensitivity were associated with substance use initiation and increased alcohol use frequency during the follow-up. Moreover, adolescents with smaller left nucleus accumbens at baseline were more likely to initiate substance use during the follow-up period. This study provides support for the link between developmental increases in reward sensitivity and substance use initiation in adolescence. The study also emphasizes the potential importance of individual differences in volumes of subcortical regions and their structural development for substance use initiation during adolescence.

Differential psychological impact of internet exposure on Internet addicts

The study explored the immediate impact of internet exposure on the mood and psychological states of internet addicts and low internet-users. Participants were given a battery of psychological tests to explore levels of internet addiction, mood, anxiety, depression, schizotypy, and autism traits. They were then given exposure to the internet for 15 min, and re-tested for mood and current anxiety. Internet addiction was associated with long-standing depression, impulsive nonconformity, and autism traits. High internet-users also showed a pronounced decrease in mood following internet use compared to the low internet-users. The immediate negative impact of exposure to the internet on the mood of internet addicts may contribute to increased usage by those individuals attempting to reduce their low mood by re-engaging rapidly in internet use.