Concurrent behavioral modeling and multimodal neuroimaging reveals how feedback affects the performance of decision making in internet gaming disorder.

Internet gaming disorder (IGD) prompts inquiry into how feedback from prior gaming rounds influences subsequent risk-taking behavior and potential neural mechanisms. Forty-two participants, including 15 with IGD and 27 health controls (HCs), underwent a sequential risk-taking task. Hierarchy Bayesian modeling was adopted to measure risky propensity, behavioral consistence, and affection by emotion ratings from last trial. Concurrent electroencephalogram and functional near-infrared spectroscopy (EEG-fNIRS) recordings were performed to demonstrate when, where and how the previous-round feedback affects the decision making to the next round. We discovered that the IGD illustrated heightened risk-taking propensity as compared to the HCs, indicating by the computational modeling (p = 0.028). EEG results also showed significant time window differences in univariate and multivariate pattern analysis between the IGD and HCs after the loss of the game. Further, reduced brain activation in the prefrontal cortex during the task was detected in IGD as compared to that of the control group. The findings underscore the importance of understanding the aberrant decision-making processes in IGD and suggest potential implications for future interventions and treatments aimed at addressing this behavioral addiction.

White matter integrity of right frontostriatal circuit predicts internet addiction severity among internet gamers.

Excessive use of the internet, which is a typical scenario of self-control failure, could lead to potential consequences such as anxiety, depression, and diminished academic performance. However, the underlying neuropsychological mechanisms remain poorly understood. This study aims to investigate the structural basis of self-control and internet addiction. In a cohort of 96 internet gamers, we examined the relationships among grey matter volume and white matter integrity within the frontostriatal circuits and internet addiction severity, as well as self-control measures. The results showed a significant and negative correlation between dACC grey matter volume and internet addiction severity (p < 0.001), but not with self-control. Subsequent tractography from the dACC to the bilateral ventral striatum (VS) was conducted. The fractional anisotropy (FA) and radial diffusivity of dACC-right VS pathway was negatively (p = 0.011) and positively (p = 0.020) correlated with internet addiction severity, respectively, and the FA was also positively correlated with self-control (p = 0.036). These associations were not observed for the dACC-left VS pathway. Further mediation analysis demonstrated a significant complete mediation effect of self-control on the relationship between FA of the dACC-right VS pathway and internet addiction severity. Our findings suggest that the dACC-right VS pathway is a critical neural substrate for both internet addiction and self-control. Deficits in this pathway may lead to impaired self-regulation over internet usage, exacerbating the severity of internet addiction.

Connectome-based prediction of craving for gaming in internet gaming disorder.

BACKGROUND: Craving-related brain responses have been associated with the emergence and maintenance of addictions. However, little is known about brain network organizations underlying cravings in internet gaming disorder (IGD). METHODS: Sixty-six IGD subjects and 61 matched individuals with recreational game use (RGU) were scanned while performing a cue-craving task. A recently developed whole-brain analysis approach, connectome-based predictive modelling (CPM) with leave-one-out cross-validation was conducted to identify networks that predicted craving responses in IGD. Then, the craving network was tested in different brain states (cue-craving under deprivation) to investigate replicability. RESULTS: CPM identified an IGD craving network, as indicated by a significant correspondence between predicted and actual craving values (r = 0.49, p < 0.001), characterized by within-network default mode (DMN) connectivity and connectivity between canonical networks implicated in executive/cognitive control (frontoparietal, medial frontal, DMN) and reward responsiveness (subcortical, motor/sensory). Network strength in the cue-craving task during gaming deprivation also predicted IGD craving scores (r = 0.43, p = 0.017), indicating network replication across brain states. CONCLUSIONS: The CPM results demonstrate that individual differences in cognitive, attention, and control network function can predict craving intensities in IGD subjects. These networks may be targets for potential interventions using brain modulation.

Viewing personalized video clips recommended by TikTok activates default mode network and ventral tegmental area.

Cutting-edge recommendation algorithms have been widely used by media platforms to suggest users with personalized content. While such user-specific recommendations may satisfy users' needs to obtain intended information, some users may develop a problematic use pattern manifested by addiction-like undesired behaviors. Using a popular video sharing and recommending platform (TikTok) as an example, the present study first characterized use-related undesired behaviors with a questionnaire, then investigated how personally recommended videos modulated brain activity with an fMRI experiment. We found more undesired symptoms were related to lower self-control ability among young adults, and about 5.9% of TikTok users may have significant problematic use. The fMRI results showed higher brain activations in sub-components of the default mode network (DMN), ventral tegmental area, and discrete regions including lateral prefrontal, anterior thalamus, and cerebellum when viewing personalized videos in contrast to non-personalized ones. Psychophysiological interaction analyses revealed stronger coupling between activated DMN subregions and neural pathways underlying auditory and visual processing, as well as the frontoparietal network. This study highlights the functional heterogeneity of DMN in viewing personalized videos and may shed light on the neural underpinnings of how recommendation algorithms are able to keep the user's attention to suggested contents.

Age-related and individual variations in altered prefrontal and cerebellar connectivity associated with the tendency of developing internet addiction.

Internet addiction refers to problematic patterns of internet use that continually alter the neural organization and brain networks that control impulsive behaviors and inhibitory functions. Individuals with elevated tendencies to develop internet addiction represent the transition between healthy and clinical conditions and may progress to behavioral addictive disorders. In this network neuroscience study, we used resting-state functional magnetic resonance imaging (rs-fMRI) to examine how and whether individual variations in the tendency of developing internet addiction rewire functional connectivity and diminish the amplitude of spontaneous low-frequency fluctuations in healthy brains. The influence of neurocognitive aging (aged over 60 years) on executive-cerebellar networks responsible for internet addictive behavior was also investigated. Our results revealed that individuals with an elevated tendency of developing internet addiction had disrupted executive-cerebellar networks but increased occipital-putamen connectivity, probably resulting from addiction-sensitive cognitive control processes and bottom-up sensory plasticity. Neurocognitive aging alleviated the effects of reduced mechanisms of prefrontal and cerebellar connectivity, suggesting age-related modulation of addiction-associated brain networks in response to compulsive internet use. Our findings highlight age-related and individual differences in altered functional connectivity and the brain networks of individuals at a high risk of developing internet addictive disorders. These results offer novel network-based preclinical markers of internet addictive behaviors for individuals of different ages.

Efficacy of single-session transcranial direct current stimulation on addiction-related inhibitory control and craving: a randomized trial in males with Internet gaming disorder.

BACKGROUND: Transcranial direct current stimulation (tDCS) of the dorsolateral prefrontal cortex (dlPFC) may reduce substance use and other addictive behaviours. However, the cognitive mechanisms that underpin such effects remain unclear. Impaired inhibitory control linked to hypoactivation of the prefrontal cortex may allow craving-related motivations to lead to compulsive addictive behaviours. However, very few studies have examined whether increasing the activation of the dlPFC via anodal tDCS could enhance inhibitory control over addiction-related distractors. The current study aimed to enrich empirical evidence related to this issue. METHODS: Thirty-three males with Internet gaming disorder underwent active (1.5 mA for 20 minutes) and sham tDCS 1 week apart, in randomized order. We assessed inhibitory control over gaming-related distractors and craving pre- and post-stimulation. RESULTS: Relative to sham treatment, active tDCS reduced interference from gaming-related (versus non-gaming) distractors and attenuated background craving, but did not affect cue-induced craving. LIMITATIONS: This study was limited by its relatively small sample size and the fact that it lacked assessments of tDCS effects on addictive behaviour. Future tDCS studies with multiple sessions in larger samples are warranted to examine the effects on addictive behaviours of alterations in addiction-related inhibitory control. CONCLUSION: These findings demonstrate that stimulation of the dlPFC influences inhibitory control over addiction-related cues and addiction-related motivation. This is the first empirical study to suggest that enhanced inhibitory control may be a cognitive mechanism underlying the effects of tDCS on addictions like Internet gaming disorder. Our finding of attenuated background craving replicated previous tDCS studies. Intriguingly, our finding of distinct tDCS effects on 2 forms of craving suggests that they may have disparate underlying mechanisms or differential sensitivity to tDCS. CLINICAL TRIALS #: NCT03352973.

Neurophysiological and Cognitive Correlates of Error Processing Deficits in Internet Gaming Disorder.

The ability to detect and correct errors is a critical aspect of human cognition. Neuronal dysfunction in error processing has been reported in addictive disorders. The aim of this study was to investigate neural systems underlying error processing using event-related potentials (ERPs) and current source localization as well as neurocognitive executive function tests in patients with Internet gaming disorder (IGD). A total of 68 individuals (34 patients with IGD and 34 healthy controls [HCs]) were included, and two ERP components, error-related negativity (ERN) and error positivity (Pe), were extracted during a GoNogo task. Patients with IGD exhibited significantly reduced ERN and Pe amplitudes compared with HCs. Standardized low-resolution brain electromagnetic tomography (sLORETA) in between-group comparisons revealed that patients with IGD had decreased source activations of the Pe component in the anterior cingulate cortex (ACC) under the Nogo condition. These ERP changes were associated with deficits in decision-making and response inhibition in IGD patients. The results suggest that IGD may be associated with functional abnormalities in the ACC and alterations in neural activity related to both the early unconscious and the later conscious stages of error processing, as well as deficits in area of decision-making.

Addiction Research Unit: Affective and cognitive mechanisms of specific Internet-use disorders.

In the eleventh International Classification of Diseases (ICD-11) of the World Health Organization, gambling disorder and gaming disorder are included in the category 'disorders due to addictive behaviours', which can be specified further as occurring either predominantly offline or predominantly online. Other specific problematic behaviours may be considered for the category 'other specified disorders due to addictive behaviours'. The Research Unit FOR 2974, funded by the German Research Foundation (Deutsche Forschungsgemeinschaft, DFG), focuses on the most prominent online addictive behaviours: gaming, pornography use, buying-shopping and social-networks use. The main goal of the Research Unit is to contribute to a better understanding of the common and differential psychological as well as neurobiological mechanisms involved in these specific types of Internet-use disorders. We aim to investigate theoretically argued (bio)psychological processes with a focus on concepts coming from research of substance-use disorders, for example, cue reactivity and craving, executive functions and specific inhibitory control, coping, implicit cognitions, and decision making. One central characteristic of the Research Unit is that we will investigate all participants using a comprehensive core battery of experimental paradigms, neuropsychological tasks, questionnaires, biomarkers, ambulatory assessment, and a 6-month follow-up survey. Beyond the anticipated contributions to the scientific understanding of the mechanisms involved in the development and maintenance of respective online addictive behaviours, we also expect contributions to clinical practice by showing which affective and cognitive mechanisms may be addressed more intensively to optimize treatment.

Resting-state connectome-based support-vector-machine predictive modeling of internet gaming disorder.

Internet gaming disorder (IGD), a worldwide mental health issue, has been widely studied using neuroimaging techniques during the last decade. Although dysfunctions in resting-state functional connectivity have been reported in IGD, mapping relationships from abnormal connectivity patterns to behavioral measures have not been fully investigated. Connectome-based predictive modeling (CPM)-a recently developed machine-learning approach-has been used to examine potential neural mechanisms in addictions and other psychiatric disorders. To identify the resting-state connections associated with IGD, we modified the CPM approach by replacing its core learning algorithm with a support vector machine. Resting-state functional magnetic resonance imaging (fMRI) data were acquired in 72 individuals with IGD and 41 healthy comparison participants. The modified CPM was conducted with respect to classification and regression. A comparison of whole-brain and network-based analyses showed that the default-mode network (DMN) is the most informative network in predicting IGD both in classification (individual identification accuracy = 78.76%) and regression (correspondence between predicted and actual psychometric scale score: r = 0.44, P < 0.001). To facilitate the characterization of the aberrant resting-state activity in the DMN, the identified networks have been mapped into a three-subsystem division of the DMN. Results suggest that individual differences in DMN function at rest could advance our understanding of IGD and variability in disorder etiology and intervention outcomes.

Reduced frontostriatal functional connectivity and associations with severity of Internet gaming disorder.

Cognitive, functional, and structural brain factors involving frontal executive and striatal reward networks have been implicated in Internet gaming disorder (IGD). However, frontostriatal network connectivity and its association with addiction severity are poorly understood in IGD. Resting-state fMRI data from 337 subjects (130 with IGD, 207 with recreational game use [RGU]) were collected. Striatal-cortical communications were measured with resting-state functional connectivity (FC) using coherent spontaneous fluctuations in the blood-oxygenation-level-dependent fMRI signal. Correlations were calculated between FC measures and IGD-related assessments (addiction severity and craving scores). Decreased FC was predominantly observed in IGD subjects, with IGD subjects showing decreased FC between the putamen and superior frontal gyrus (SFG), middle frontal gyrus (MFG), and inferior frontal gyrus (IFG) and the ventral striatum and IFG, superior temporal gyrus, and MFG. Disorder severity and craving scores were negatively correlated with FC between striatal and frontal brain regions. Associations between diminished FC in corticostriatal circuitry and clinical features (IGD craving, severity) suggest potential therapeutic targets for neuromodulation treatments. The extent to which frontostriatal circuits involving executive control over reward processes may be altered to treat IGD warrants additional study.

Convergent cross-sectional and longitudinal evidence for gaming-cue specific posterior parietal dysregulations in early stages of internet gaming disorder.

Exaggerated reactivity to drug-cues and emotional dysregulations represent key symptoms of early stages of substance use disorders. The diagnostic criteria for (Internet) gaming disorder strongly resemble symptoms for substance-related addictions. However, previous cross-sections studies revealed inconsistent results with respect to neural cue reactivity and emotional dysregulations in these populations. To this end, the present fMRI study applied a combined cross-sectional and longitudinal design in regular online gamers (n = 37) and gaming-naïve controls (n = 67). To separate gaming-associated changes from predisposing factors, gaming-naive subjects were randomly assigned to 6 weeks of daily Internet gaming or a non-gaming condition. At baseline and after the training, subjects underwent an fMRI paradigm presenting gaming-related cues and non-gaming-related emotional stimuli. Cross-sectional comparisons revealed gaming-cue specific enhanced valence attribution and neural reactivity in a parietal network, including the posterior cingulate in regular gamers as compared to gaming naïve-controls. Longitudinal analysis revealed that 6 weeks of gaming elevated valence ratings as well as neural cue-reactivity in a similar parietal network, specifically the posterior cingulate in previously gaming-naïve controls. Together, the longitudinal design did not reveal supporting evidence for altered emotional processing of non-gaming associated stimuli in regular gamers whereas convergent evidence for increased emotional and neural reactivity to gaming-associated stimuli was observed. Findings suggest that exaggerated neural reactivity in posterior parietal regions engaged in default mode and automated information processing already occur during early stages of regular gaming and probably promote continued engagement in gaming behavior.

A neural mechanism of the relationship between impulsivity and emotion dysregulation in patients with Internet gaming disorder.

Impulsivity and emotion dysregulation have been known to be risk factors for Internet gaming disorder (IGD), but their underlying neural mechanisms are not yet fully understood. Given that the prefrontal cortex has a key role in higher order cognition and addiction, the present study aimed to investigate emotional influences on response inhibition in situations with different cognitive demands. A total of 41 young male adults (20 with and 21 without IGD) were scanned while performing two versions of an emotional go/no-go task with demands on low and high working memory load. Patients with IGD showed a failure in response inhibition and increased activation of widespread brain regions, including prefrontal, motor-sensory, parietal, occipital, insula, and striatal regions across tasks. Among these regions, involvement of the dorsolateral prefrontal cortex and ventral striatum was observed only during the task with high demands on working memory. Moreover, it was also only during the high-load task that interaction between response inhibition and emotional states was observed in the dorsomedial prefrontal cortex, with observations revealing that its alteration in patients with IGD was associated with number of hours spent on Internet gaming. Our findings highlight a failure of response inhibition and dysfunction within the inhibitory control network. The special significance of our study is that dysfunctional dorsomedial prefrontal cortex may mediate abnormal emotional influences on response inhibition in patients with IGD.

Attached to Virtual Dreams: The Mediating Role of Maladaptive Daydreaming in the Relationship Between Attachment Styles and Problematic Social Media Use.

ABSTRACT: Maladaptive daydreaming describes excessive fantasy activity that interferes with an individual's life. Surprisingly, the precursors of maladaptive daydreaming and its role in excessive involvement in virtual worlds have been scarcely investigated. In the current study, we examined the relationships among attachment styles, maladaptive daydreaming, and problematic social media use (PSMU) in a sample of community-dwelling adults. Eight hundred seventy-seven participants between 18 and 68 years old were recruited via an online survey and asked to fill out self-reported measures on attachment styles, maladaptive daydreaming, and PSMU. Mediation analyses showed that maladaptive daydreaming is a significant mediator in the relationships between preoccupied and fearful attachment styles and PSMU, suggesting that maladaptive daydreaming partly explains the established link between insecure attachment styles and excessive use of social media. Individuals with PSMU fostered by maladaptive daydreaming may benefit from clinical interventions that promote the use of adaptive regulatory strategies to develop feelings of security and self-confidence that may serve to reduce the excessive involvement in social media.

The relationship between nomophobia and psychiatric symptoms in adolescents.

OBJECTIVE: This study aimed to find out whether nomophobia levels are higher in adolescents with internalising or externalising disorders than healthy adolescents and to investigate the correlation of nomophobia levels with externalising and internalising symptoms. METHODS: K-SADS (Kiddie Schedule for Affective Disorders and Schizophrenia) was applied to 139 adolescents (ages 13-18) and they were asked to fill No Mobile Phone Questionnaire (NMP-Q) and Revised Child Anxiety and Depression Scale (RCADS), while the parents were asked to complete Conners Parent Rating Scale-48 (CPRS-48). RESULTS: There were no significant differences in nomophobia total scores between the three study groups. However, losing connectedness (LC) and not being able to access information (NAI) subscores were significantly higher in group with internalising disorder than healthy controls and there was no significant difference between group with externalising disorder and healthy group. Separation anxiety, social phobia, total anxiety, depression, hyperactivity and oppositional problems positively correlated with nomophobia total score. Conduct problems correlated with only LC. Total anxiety and hyperactivity predicted nomophobia total score. CONCLUSIONS: Since anxiety and hyperactivity were predictors of nomophobia according to the study, adolescents with attention deficit hyperactivity disorder or anxiety disorder should be examined for nomophobia as well.Key pointsNomophobia levels of internalising and externalising disordered groups did not differ.Internalising group had higher scores in two sub-dimensions of nomophobia.All anxiety and depression symptoms correlated with nomophobia.Hyperactivity and oppositional symptoms correlated with nomophobia.Total anxiety and hyperactivity were predictors of nomophobia.

Electroencephalography-detected neurophysiology of internet addiction disorder and internet gaming disorder in adolescents - A review.

INTRODUCTION: Internet Addiction Disorder (IAD) is an umbrella term for various types of Internet-based behavioural addiction, whereas Internet Gaming Disorder (IGD) addresses a specific type of IAD that is postulated to be due to a lack of control in impulse inhibition. IGD is an area of concern in the Diagnostic and Statistics Manual of Mental Disorders (DSM-5), which can be objectively assessed by dysfunctional behaviour and the increasing time of being online, particularly during the COVID-19 pandemic. Electroencephalography (EEG) identifies amplitude changes in the evoked response potential (ERP) among IGDs, correlated with underlying comorbidities. MATERIALS AND METHODS: A scoping review was performed to elaborate on the research regarding resting-state EEG and task-based EEG, particularly for Go/No-go paradigms pertaining to subjects with IAD or specifically IGD. The role of EEG was identified in its diagnostic capability to identify the salient changes that occurred in the response to reward network and the executive control network, using restingstate and task-based EEG. The implication of using EEG in monitoring the therapy for IAD and IGD was also reviewed. RESULTS: EEG generally revealed reduced beta waves and increased theta waves in addicts. IGD with depression demonstrated increased theta and decreased alpha waves. Whereas increased P300, a late cognitive ERP component, was frequently associated with impaired excessive allocation of attentional resources of the IAD towards addiction-specific cues. IGD had increased whole brain delta waves at baseline, which showed significant reduction post therapy. CONCLUSION: EEG can identify distinct neurophysiological changes among Internet Addiction Disorder and Internet Gaming Disorder that are akin to substance abuse disorders.

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.

Cue-elicited craving-related lentiform activation during gaming deprivation is associated with the emergence of Internet gaming disorder.

Internet gaming disorder (IGD) is associated with negative health measures. However, little is known regarding the brain mechanisms or cognitive factors that may predict transitions from regular game use (RGU) to IGD. Such knowledge may help identify individuals who are particularly vulnerable to IGD and aid in prevention efforts. One hundred forty-nine individuals with RGU were scanned when they were performing a cue-elicited-craving task before gaming and after gaming was suddenly ceased. One year later, 23 were found to have developed IGD (RGU_IGD). We compared the original data from these 23 RGU_IGD subjects and 23 one-to-one matched subjects still meeting criteria for RGU (RGU_RGU). RGU_IGD and RGU_RGU subjects showed similarities in the cue-elicited-craving task before gaming. Significant group-by-time interaction identified the bilateral lentiform nucleus. Post hoc analysis showed the interaction was related to increased activation in the RGU_IGD subjects following gaming. Significant correlations were observed between self-reported cravings and lentiform activation in the RGU_IGD subjects. Among individuals with RGU, gaming-cue-induced lentiform activation following a session of gaming may predict subsequent development of IGD. The findings suggest a biological mechanism for emergence of IGD that may help inform prevention interventions.

The Modulation of Reward and Habit Systems by Acupuncture in Adolescents with Internet Addiction.

Purpose: Acupuncture is an effective therapy for Internet addiction (IA). However, the underlying mechanisms of acupuncture in relieving compulsive Internet use remain unknown. Neuroimaging studies have demonstrated the role of the ventral striatum (VS) in the progress of IA; hence, the aim of this study was to explore the effects of acupuncture on the resting-state functional connectivity (rsFC) and relevant network of VS in IA. Methods: Twenty-seven IA individuals and 30 demographically matched healthy control subjects (HCs) were recruited in this study. We acquired the functional magnetic resonance imaging (fMRI) data in IA subjects before and after 40 days of acupuncture treatment. Seed-to-voxel and ROI-to-ROI analyses were applied to detect the rsFC alterations of the VS and related network in IA subjects and to investigate the modulation effect of acupuncture on the rsFC. Results: Compared with HCs, IA subjects exhibited enhanced rsFC of the right ventral rostral putamen (VRP) with the left orbitofrontal cortex (OFC), premotor cortex (PMC), cerebellum, and right ventromedial prefrontal cortex (vmPFC). In the network including these five ROIs, IA also showed increased ROI-to-ROI rsFC. Using a paired t-test in IA subjects before and after 40 days of acupuncture, the increased ROI-to-ROI rsFC was decreased (normalized to HC) with acupuncture, including the rsFC of the right VRP with the left OFC, PMC, and cerebellum, and the rsFC of the left cerebellum with the left OFC, PMC, and right vmPFC. Furthermore, the change in rsFC strength between the right VRP and left cerebellum in IA individuals was found positively correlated with the Internet craving alleviation after acupuncture. Conclusions: These findings verified the modulation effect of acupuncture on functional connectivity of reward and habit systems related to the VS in IA individuals, which might partly represent the underlying mechanisms of acupuncture on IA.

The relationship between maladaptive personality functioning and problematic technology use in adolescence: A cluster analysis approach.

In the last two decades, scientific research has explored the problematic use of internet, videogames and mobile phones. However, there is still little consistent knowledge regarding the co-occurrence of problematic technology use and the role of maladaptive personality characteristics in adolescence. The present study aimed to investigate adolescents' styles of technology use with a cluster analysis approach focusing on personality functioning. The sample comprised 408 Italian adolescents (46.3% males) aged 11 to 18 years (M age  = 13.80; SD = 2.08). Data were collected using the Internet Addiction Test, the Videogame Dependency Scale, the Test of Mobile-Phone Dependence Brief Form and the Personality Inventory for DSM5 Brief Form. Results provided a four-cluster solution based on the co-occurrence of problematic technology use. The four clusters were labeled as follows: cluster 1: "Above average internet and mobile-phone use"; cluster 2: "Below average technology use"; cluster 3: "Above average videogame use"; and cluster 4: "Problematic technology use." Analyses on demographic variables (e.g., gender and age) demonstrated significant differences between the four groups. Adolescents with high levels of problematic technology use reported greater overall personality dysfunction than the other three groups. This finding supported our hypothesis on maladaptive personality functioning in adolescents at risk for addiction. Finally, the Antagonism domain played a specific role in differentiating the severity of adolescents' involvement in technology use. Further studies are needed to confirm our findings and to plan preventive interventions as well as therapeutic treatments.

Dysfunction of Self-Control in Facebook Addiction: Impulsivity Is the Key.

Facebook is one of the most popular social network sites and communication platforms. However, besides many positive elements related to the use of this network site, in some cases it may lead to addiction. Therefore, the main aim of our study was to identify Facebook addiction predictors, in particular, to verify whether impulsivity, as a dimension of self-control, is an important predictor of this type of addiction. We also examined whether Facebook addiction predictors such as time spent using Facebook, use of Facebook smartphone apps, state orientation and female gender would be significant in our model of Facebook addiction. The 234 participants in the study were assessed using the Facebook Intrusion Questionnaire, the Brief Self-Control Scale and the Action Control Scale. Impulsivity as a dimension of self-control, action control, amount of time spent on Facebook, Facebook app use and gender were found to be related to Facebook addiction. Specifically, a high level of impulsivity, more time spent using Facebook, female gender and Facebook smartphone app use are predictors of Facebook addiction. However, the relation between state orientation, restraint as a dimension of self-control and Facebook addiction was insignificant. Our results may indicate the role of impulsivity as a dimension of self-control in Facebook addiction. In addition, they may suggest that self-control should be taken into account not only as a one-dimensional but also as a multidimensional construct in Facebook addiction research. Our findings may also contribute to the better preparation of prevention and therapeutic programmes for people at risk of Facebook addiction.