How previous experience shapes future affective subjective ratings: A follow-up study investigating implicit learning and cue ambiguity.

People use their previous experience to predict future affective events. Since we live in ever-changing environments, affective predictions must generalize from past contexts (from which they may be implicitly learned) to new, potentially ambiguous contexts. This study investigated how past (un)certain relationships influence subjective experience following new ambiguous cues, and whether past relationships can be learned implicitly. Two S1-S2 paradigms were employed as learning and test phases in two experiments. S1s were colored circles, S2s negative or neutral affective pictures. Participants (Experiment 1 N = 121, Experiment 2 N = 116) were assigned to the certain (CG) or uncertain group (UG), and they were presented with 100% (CG) or 50% (UG) S1-S2 congruency during an uninstructed (Experiment 1) or implicit (Experiment 2) learning phase. During the test phase both groups were presented with a new 75% S1-S2 paradigm, and ambiguous (Experiment 1) or unambiguous (Experiment 2) S1s. Participants were asked to rate the expected valence of upcoming S2s (expectancy ratings), or their experienced valence and arousal (valence and arousal ratings). In Experiment 1 ambiguous cues elicited less negative expectancy ratings, and less unpleasant valence ratings, independently of prior experience. In Experiment 2, both groups showed similar expectancies, predicting upcoming pictures' valence according to the 75% contingencies of the test phase. Overall, we found that in the presence of ambiguous cues subjective affective experience is dampened, and that implicit previous experience does not emerge at the subjective level by significantly shaping reported affective experience.

Using Social Media for Social Motives Moderates the Relationship between Post-Traumatic Symptoms during a COVID-19-Related Lockdown and Improvement of Distress after Lockdown.

Previous research reported inconsistent results on the relationship between social media (SM) use and psychological well-being, suggesting the importance of assessing possible moderators, e.g., motives for SM use. However, no longitudinal study has yet investigated whether, among people who use SM, specific motives for using SM may represent protective/risk factors for the development of psychological distress, especially after a stressful event. Our longitudinal study aimed at assessing the moderating role of motives for using SM (i.e., coping, conformity, enhancement, social motives) in the relationship between COVID-19 pandemic-related post-traumatic stress symptoms during the lockdown and changes in general distress after lockdown. At Time 1 (during the first lockdown in Italy), 660 participants responded to an online survey, reporting their post-traumatic symptoms, motives for using SM, and general distress (i.e., anxiety, depression, and stress symptoms). At Time 2 (three months later, following lockdown), 117 participants volunteered to continue with the follow-up survey assessing general distress symptoms again. Results showed that among those who had experienced more severe post-traumatic symptoms at Time 1, using SM for social motives was associated with more improvement of general distress symptoms. No evidence was found of moderating effects of other motives for SM use. The findings suggest that social connections may have helped to cope with stress during forced confinement, and that SM use may be beneficial for mental health when motivated by maintaining social interactions.

Problematic social media use is statistically predicted by using social media for coping motives and by positive reinforcement processes in individuals with high COVID-19-related stress levels.

It is important to understand the relationship between stress and problematic use of social media (PUSM). However, no study to our knowledge has yet investigated the longitudinal relationship between perceived stress and PUSM via positive and negative reinforcement processes. The present study investigated relationships between COVID-19-pandemic-related stress and PUSM and possible moderating effects of motives for using social media (positive and/or negative reinforcement) during and following a COVID-19-pandemic-related lockdown. Six-hundred-and-sixty participants initially completed a survey including self-report measures of PUSM, COVID-19-pandemic-related stress, and motives for using social media (i.e., for negative reinforcement involving coping and conformity or positive reinforcements involving enhancement and social motives). During the COVID-19 outbreak recovery period, 117 participants again completed the survey. Bayesian analyses revealed that PUSM was associated with higher COVID-19-pandemic-related stress levels and use of social media for coping, conformity, and enhancement purposes. Longitudinally, PUSM symptom worsening was associated with increased use of social media for coping motives regardless of levels of perceived stress. Use of social media for conformity and enhancement purposes moderated relationships between stress levels during lockdown and PUSM symptoms worsening after lockdown. Our findings corroborate the hypothesis that negative reinforcement processes may be key factors in PUSM symptom worsening regardless of perceived stress. Concurrently, high levels of stress may worsen PUSM through positive reinforcement processes.

Heterogeneity of smartphone impact on everyday life and its relationship with personality and psychopathology: A latent profile analysis.

BACKGROUND: The relationships between problematic smartphone use and psychological factors have been extensively investigated. However, previous studies generally used variable-centered approaches, which hinder an examination of the heterogeneity of smartphone impact on everyday life. OBJECTIVE: In the present study, we capitalized on latent profile analysis to identify various classes of smartphone owners based on the impact associated with smartphone use (e.g., unregulated usage, preference for smartphone-mediated social relationships) and to compare these classes in terms of established psychological risk factors for problematic smartphone use. METHOD: We surveyed 934 young adults with validated psychometric questionnaires to assess the impact of smartphones, psychopathological symptoms, self-esteem and impulsivity traits. RESULTS: Smartphone users fall into four latent profiles: users with low smartphone impact, users with average smartphone impact, problematic smartphone users, and users favoring online interactions. Individuals distributed in the problematic smartphone user profile were characterized by heightened psychopathological symptoms (stress, anxiety, depression, obsessive-compulsive tendencies) and impulsivity traits. Moreover, users who preferred online interactions exhibited the highest symptoms of social anxiety and the lowest levels of self-esteem. CONCLUSIONS: These findings further demonstrate the multidimensionality and heterogeneity of the impact of smartphone use, calling for tailored prevention and intervention strategies.

Emotion regulation strategies differentially modulate neural activity across affective prediction stages: An HD-EEG investigation.

Emotion regulation (ER) strategies can influence how affective predictions are constructed by the brain (generation stage) to prearrange action (implementation stage) and update internal models according to incoming stimuli (updating stage). However, neurocomputational mechanisms by which this is achieved are unclear. We investigated through high-density EEG if different ER strategies (expressive suppression vs. cognitive reappraisal) predicted event-related potentials (ERPs) and brain source activity across affective prediction stages, as a function of contextual uncertainty. An S1-S2 paradigm with emotional faces and pictures as S1s and S2s was presented to 36 undergraduates. Contextual uncertainty was manipulated across three blocks with 100, 75, or 50% S1-S2 affective congruency. The effects of ER strategies, as assessed through the Emotion Regulation Questionnaire, on ERP and brain source activity were tested for each prediction stage through linear mixed-effects models. No ER strategy affected prediction generation. During implementation, in the 75% block, a higher tendency to suppress emotions predicted higher activity in the left supplementary motor area at 1,500-2,000 ms post-stimulus, and smaller amplitude of the Contingent Negative Variation at 2,000-2,500 ms. During updating, in the 75% block, a higher tendency to cognitively reappraise emotions predicted larger P2, Late Positive Potential, and right orbitofrontal cortex activity. These results suggest that both ER strategies interact with the levels of contextual uncertainty by differently modulating ERPs and source activity, and that different strategies are deployed in a moderately predictive context, supporting the efficient updating of affective predictive models only in the context in which model updating occurs.

Unbalanced functional connectivity at rest affects the ERP correlates of affective prediction in high intolerance of uncertainty individuals: A high density EEG investigation.

In a recent study we outlined the link between Intolerance of Uncertainty (IU) and the neural correlates of affective predictions, as constructed by the brain (generation stage) to prepare to relevant stimuli (implementation stage), and update predictive models according to incoming stimuli (updating stage). In this study we further explored whether the brain's functional organization at rest can modulate neural activity elicited within an emotional S1-S2 paradigm as a function of IU and uncertainty of S1-S2 contingencies. We computed resting state functional connectivity (RS-FC) from a 3-min resting period recorded with high density EEG, and we tested whether RS graph theory nodal measures (i.e., strength, clustering coefficient, betweenness centrality) predicted in-task ERP modulation as a function of IU. We found that RS-FC differently predicted in-task ERPs within the generation and updating stages. Higher IU levels were associated to altered RS-FC patterns within both domain-specific (i.e., right superior temporal sulcus) and domain-general regions (i.e., right orbitofrontal cortex), predictive of a reduced modulation of in-task ERPs in the generation and updating stages. This is presumably ascribable to an unbalancing between synchronization and integration within these regions, which may disrupt the exchange of information between top-down and bottom-up pathways. This altered RS-FC pattern may in turn result in the construction of less efficient affective predictions and a reduced ability to deal with contextual uncertainty in individuals high in IU.

Tracing 20 years of research on problematic use of the internet and social media: Theoretical models, assessment tools, and an agenda for future work.

Over the past two decades, there has been increasing interest in the impact of internet use and growing concern about whether problematic use of the internet (PUI) constitutes an addiction. Despite the growing number of studies investigating PUI and PUI subtypes, its conceptualization and inclusion in a classification system have not been possible yet. Several models aimed at inspiring clinical research and practice have proposed possible mechanisms involved in PUI and problematic use of social media, and multiple self-report instruments have been consequentially developed. The diversity of theoretical models and instruments currently hinders standardized assessment procedures across studies and, in turn, their comparability. The purpose of the present overview is to highlight the current conceptualization and assessment of both PUI and problematic use of social media, in order to critically discuss the existing fragmentation in the field and the need to achieve conceptual convergence. Two suggestions for future directions are also provided, i.e., define diagnostic criteria by bottom-up and top-down processes and develop a psychobiological hypothesis including the description of higher-order mechanisms involved in PUI and not other psychopathological conditions (e.g., the multiple available internet-related cues and outcomes that may lead to parallel forms of associative learning; probabilities of obtaining internet-related reinforcements; and intrinsic motivation processes).

The Relationship Between Affective and Obsessive-Compulsive Symptoms in Internet Use Disorder.

We investigated the relationships and diagnostic power of symptoms associated with affective disorders, obsessive-compulsive disorder, and drug addictions on Internet use disorder. Moreover, we tested whether Internet use disorder is characterized by a specific network of symptoms. One-hundred-and-four young adults (78 women) were assessed in laboratory using self-report measures of Internet addiction, alcohol use disorder, cannabis abuse, depression, anxiety, and stress symptoms, impulsiveness, and obsessive-compulsive symptoms. Only hoarding, obsessing, and depression symptoms were positively linked to Internet use disorder severity, with hoarding having greater power and accuracy than other obsessive-compulsive and affective symptoms. Only individuals with mild-moderate Internet use disorder were characterized by a network of strong and positive associations of affective and obsessive-compulsive symptoms. These findings may encourage future longitudinal studies aimed at identifying potential clinical criteria for the diagnosis of Internet use disorder and treatment targets.

Dealing with uncertainty: A high-density EEG investigation on how intolerance of uncertainty affects emotional predictions.

Intolerance of uncertainty (IU) can influence emotional predictions, constructed by the brain (generation stage) to prearrange action (implementation stage), and update internal models according to incoming stimuli (updating stage). However, neurocomputational mechanisms by which IU affects emotional predictions are unclear. This high-density EEG study investigated if IU predicted event-related potentials (ERPs) and brain sources activity developing along the stages of emotional predictions, as a function of contextual uncertainty. Thirty-six undergraduates underwent a S1-S2 paradigm, with emotional faces and pictures as S1s and S2s, respectively. Contextual uncertainty was manipulated across three blocks, each with 100%, 75%, or 50% S1-S2 emotional congruency. ERPs, brain sources and their relationship with IU scores were analyzed for each stage. IU did not affect prediction generation. During prediction implementation, higher IU predicted larger Contingent Negative Variation in the 75% block, and lower left anterior cingulate cortex and supplementary motor area activations. During prediction updating, as IU increased P2 to positive S2s decreased, along with P2 and Late Positive Potential in the 75% block, and right orbito-frontal cortex activity to emotional S2s. IU was therefore associated with altered uncertainty assessment and heightened attention deployment during implementation, and to uncertainty avoidance, reduced attention to safety cues and disrupted access to emotion regulation strategies during prediction updating.

Motivated attention to stimuli related to social networking sites: A cue-reactivity study.

BACKGROUND AND AIMS: It has been argued that similar to addictive behaviors, problematic Social Network sites use (PSNSU) is characterized by sensitized reward processing and cue-reactivity. However, no study to our knowledge has yet investigated cue-reactivity in PSNSU. The present study aims at investigating cue-reactivity to Social Network sites (i.e., Facebook)-related visual cues in individuals identified as problematic vs. non-problematic Facebook users by the Problematic Facebook Use Scale. METHODS: The Event-Related Potentials (ERPs) were recorded during the passive viewing of Facebook-related, pleasant, unpleasant, and neutral pictures in 27 problematic and 26 non-problematic users. Moreover, craving for Facebook usage was collected using a Likert scale. RESULTS: Despite problematic users were more likely to endorse higher craving than non-problematic ones, Facebook-related cues elicited larger ERP positivity (400-600 ms) than neutral, and comparable to unpleasant stimuli, in all Facebook users. Only in problematic users we found larger positivity (600-800 ms) to pleasant than unpleasant cues and higher craving to be related with lower later positivity (800-1,000 ms) to pleasant and unpleasant cues. DISCUSSION: Regardless of whether Facebook usage is problematic or non-problematic, Facebook-related cues seem to be motivationally relevant stimuli that capture attentional resources in the earlier stages of "motivated" attentional allocation. Moreover, our results support the view that in higher-craving problematic users, reduced abilities to experience emotions would be the result of defective emotion regulation processes that allow craving states to capture more motivational/attentional resources at the expense of other emotional states.

What's next? Neural correlates of emotional predictions: A high-density EEG investigation.

Emotions were recently reconsidered as predictions, constructed by the brain (generation stage) to prearrange action (implementation stage), and update internal models according to incoming stimuli (updating stage). However, it is unclear how emotional predictions are shaped by stimuli predictability. This study investigated the role of stimuli predictability on emotional predictions through high-density EEG. Twenty-six undergraduates underwent a S1-S2 paradigm, with emotional faces as S1s and emotional pictures as S2s. Stimuli predictability was manipulated across three blocks, in which S1 valence was predictive of S2 in the 100%, 75%, or 50% of trials. ERPs and brain sources were analyzed for each stage. During prediction generation, a larger N170/superior temporal sulcus activity emerged to fearful faces in blocks with full (100%) and medium (75%) predictive ratios. During implementation, the random block (50%) elicited a valence-independent pre-allocation of resources, reflected by a larger CNV and activation of a wide left network. In the updating stage, emotional pictures always elicited a larger LPP, while a larger P2 to neutral stimuli and a higher activity of the orbitofrontal cortex signaled early valence-dependent and late block-dependent prediction errors. These findings provide the first evidence of how stimuli predictability shape each neurocomputational stage of emotional predictions construction.

Response inhibition in problematic social network sites use: an ERP study.

Given the current literature debate on whether or not Problematic Social Network Sites Use (PSNSU) can be considered a behavioral addiction, the present study was designed to test whether, similarly to addictive behaviors, PSNSU is characterized by a deficit in inhibitory control in emotional and addiction-related contexts. Twenty-two problematic Facebook users and 23 nonproblematic users were recruited based on their score on the Problematic Facebook Use Scale. The event-related potentials were recorded during an emotional Go/Nogo Task, including Facebook-related, unpleasant, pleasant, and neutral pictures. The amplitudes of the Nogo-N2 and the Nogo-P3 were computed as measures of the detection of response conflict and response inhibition, respectively. Reaction times and accuracy also were measured. The results showed that problematic users were less accurate on both Go and Nogo trials than nonproblematic users, irrespective of picture content. For problematic users only, the Nogo-P3 amplitude was lower to Facebook-related, pleasant, and neutral than to unpleasant stimuli, suggesting less efficient inhibition with natural and Facebook-related rewards. Of note, all participants were slower to respond to Facebook-related and pleasant Go trials compared with unpleasant and neutral pictures. Consistently, the Nogo-N2 amplitude was larger to Facebook-related than all other picture contents in both groups. Overall, the findings suggest that PSNSU is associated with reduced inhibitory control. These results should be considered in the debate about the neural correlates of PSNSU, suggesting more similarities than differences between PSNSU and addictive behaviors.

A test of the pathway model of problematic smartphone use.

BACKGROUND AND AIMS: Problematic smartphone use (PSU) has been described as a growing public health issue. In the current study, we aimed to provide a unique and comprehensive test of the pathway model of PSU. This model posits three distinct developmental pathways leading to PSU: (1) the excessive reassurance pathway, (2) the impulsive pathway and (3) the extraversion pathway. METHODS: Undergraduate students (n = 795, 69.8% female, mean age = 23.80 years, sd = 3.02) completed online self-report measures of PSU (addictive use, antisocial use and dangerous use) and the psychological features (personality traits and psychopathological symptoms) underlying the three pathways. RESULTS: Bayesian analyses revealed that addictive use is mainly driven by the excessive reassurance pathway and the impulsive pathway, for which candidate etiopathological factors include heightened negative urgency, a hyperactive behavioural inhibition system and symptoms of social anxiety. Dangerous and antisocial use are mainly driven by the impulsive pathway and the extraversion pathway, for which candidate etiopathological factors include specific impulsivity components (lack of premeditation and sensation seeking) and primary psychopathy (inclination to lie, lack of remorse, callousness and manipulativeness). DISCUSSION AND CONCLUSIONS: The present study constitutes the first comprehensive test of the pathway model of PSU. We provide robust and original results regarding the psychological dimensions associated with each of the postulated pathways of PSU, which should be taken into account when considering regulation of smartphone use or tailoring prevention protocols to reduce problematic usage patterns.

Attention and affect in dysphoria: Insights from startle reflex modulation and cardiac deceleration.

The present study investigated the interplay between attention and affective disposition during emotional processing in dysphoria. Attentional and affective startle modulation and cardiac deceleration were assessed during the viewing of emotional pictures in 38 individuals with dysphoria and in 52 controls. Startle probes during picture viewing were presented at 300, 1500, 3500, 4500 ms after picture onset. Whereas controls showed the expected startle potentiation to unpleasant stimuli as compared to neutral and pleasant ones, individuals with dysphoria did not show any significant increase in startle reflex amplitude in response to unpleasant stimuli. Of note, startle potentiation during the viewing of unpleasant stimuli was significantly attenuated in the group with dysphoria relative to controls. Conversely, no significant effect concerning attentional startle modulation was noted. However, whereas individuals with dysphoria showed a prolonged cardiac deceleration when viewing unpleasant compared to neutral stimuli, the same effect was observed in controls only in the initial stage of stimuli processing. This study suggests that dysphoria is characterized by underactivation of the defensive motivational system and by prolonged attentional allocation to unpleasant stimuli. The assessment of affective startle modulation and cardiac deceleration is a valuable paradigm for unraveling dysfunctions in affective disposition and attention in dysphoria.

Appetitive and aversive motivation in depression: The temporal dynamics of task-elicited asymmetries in alpha oscillations.

The capability model of alpha asymmetries posits that state emotional manipulations are a more powerful detector of depression-related motivational deficits than alpha activity at rest. The present study used a time-frequency approach to investigate the temporal dynamics of event-related changes in alpha power during passive viewing of emotional pictures in individuals with dysphoria (n = 23) and in individuals without dysphoria (n = 24). In the whole group, the processing of pleasant and unpleasant compared to neutral pictures was associated with a decrease in event-related alpha power (i.e., alpha desynchronization) at centro-parietal and parietal scalp sites in the 538-1400 ms post-stimulus. The group with dysphoria revealed a smaller alpha desynchronization than the group without dysphoria in response to pleasant, but not neutral and unpleasant, stimuli at frontal, fronto-central and centro-parietal sites. Interestingly, at central and centro-parietal scalp sites, the difference between groups in response to pleasant stimuli was lateralized to the right hemisphere, whereas no clear lateralization was observed at frontal and fronto-central scalp sites. These findings suggest that decreased cortical activity (i.e., reduced alpha desynchronization) in a network involving bilateral frontal and right-lateralized parietal regions may provide a specific measure of deficits in approach-related motivation in depression.

Problematic Internet Use: The Relationship Between Resting Heart Rate Variability and Emotional Modulation of Inhibitory Control.

A growing literature suggests that problematic Internet use (PIU) is associated with defective inhibitory control. In this study, we sought to investigate the ability to inhibit prepotent motor responses in an emotional context in individuals with PIU, and to examine the relationship between inhibitory control and resting heart rate variability (HRV), which is regarded as a measure of self-regulation and adaptability. Problematic users (PU, n = 20) and nonproblematic users (non-PU, n = 20) completed an emotional Go/NoGo task, involving the presentation of unpleasant, pleasant, and neutral pictures. The electrocardiogram was recorded at rest for a 3-minute period. PU showed lower resting HRV, relative to non-PU. Although reaction times (RTs) to Go task stimuli were not faster in PU, relative to non-PU, accuracy rates were significantly lower among PU, irrespective of pictures' emotional content. Only among PU did lower resting HRV predict lower response accuracy in pleasant and unpleasant Go trials and less efficient task performance (combining RTs to Go trials and accuracy to NoGo trials) upon presentation of unpleasant stimuli. Our findings suggest that reduced HRV is a potential indicator of defective inhibitory control in an emotional context in PIU.

Food processing and emotion regulation in vegetarians and omnivores: An event-related potential investigation.

The present study investigated cognitive reappraisal during exposure to vegetarian and nonvegetarian food cues in food-deprived vegetarian and omnivore participants. In particular, we were interested in clarifying the motivational meaning of the foods that vegetarians avoid, as revealed by self-reported food craving, valence, and arousal, as well as by ERP measures of neural processing during passive viewing and emotional regulation. Twenty-four vegetarians and twenty-one omnivores were instructed to either passively look at the pictures (Watch) or to change the appetitive value of the food (Increase or Decrease). In vegetarians, meat and fish dishes elicited lower desire to eat, pleasantness, and arousal during each condition as compared to both omnivores and vegetarian food. In contrast with the subjective data, no group differences were observed in any of the ERP measures, suggesting that similar neural processing of food-cues occurred in vegetarians and omnivores both during passive viewing and cognitive reappraisal. Concerning the late ERP effects during cognitive reappraisal, we found an enhancement of the P300 and LPP amplitudes during the Increase and the Decrease as compared to the Watch condition and a reduction of the SW amplitude in the Decrease as compared to Watch condition. These results suggest that in a food deprivation condition it is difficult to reduce the appetitive value of food stimuli, as this cognitive strategy appears to require greater effort and a longer time to be implemented with respect to up-regulation. Overall, our findings suggest that, in vegetarians, aversion towards nonvegetarian food prevails at the subjective level and is consistent with their personal beliefs. In contrast, at the neural level, the intrinsic motivational salience of this type of food is preserved.

Single-Session Attention Bias Modification Training in Victims of Work-Related Accidents.

Individuals who experienced traumatic work-related accidents frequently show cognitive deficits and biased processing of trauma-relevant information, which, in turn, could increase the risk of further accidents. The attention bias modification training (ABMT) is designed to reduce hypervigilance toward and enhance attentional disengagement from threat stimuli. The aim of the present study was to assess whether it is possible to implicitly reduce the attentional bias toward trauma-related stimuli through a single session of ABMT in individuals who experienced a traumatic occupational accident. Nineteen individuals who had experienced a traumatic work-related accident and 11 workers who never experienced a work accident (control group) underwent a preliminary assessment of cognitive performance (executive functions and sustained attention) and an evaluation of the attentional bias toward accident-related pictures by means of a dot-probe task. The results showed that injured workers performed more poorly than controls in tasks of executive functions and concentration abilities. Also, injured workers showed an attentional bias toward trauma reminders (i.e., faster reaction times to probes replacing trauma-related pictures). Injured workers were then randomly allocated to a single-session of ABMT (N = 10) or to an Attention Control Condition (ACC; N = 9). After the training, the dot-probe task was administered again to assess changes in the attentional bias toward trauma-relevant pictures. Injured workers who underwent the ABMT, but not those who underwent the ACC, showed a significant reduction of the attentional bias from pre- to post-training. Overall, these results support previous findings reporting an association between traumatic occupational accidents and cognitive dysfunctions. More importantly, these preliminary findings add to a growing body of evidence suggesting the effectiveness of a short ABMT in reducing the attentional bias after a traumatic workplace accident.

Modeling Problematic Facebook Use: Highlighting the role of mood regulation and preference for online social interaction.

A validated theoretical model of Problematic Facebook Use (PFU) is currently lacking in the literature. The cognitive-behavioral model of generalized Problematic Internet Use (PIU) proposed by Caplan (2010) may provide a conceptual basis for understanding the problematic use of Social Networking Sites. The present study aimed at contributing to the discussion on the conceptualization of PFU by testing the feasibility of the model of generalized PIU in the context of PFU. The Italian version of the Problematic Facebook Use Scale (PFUS; including five subscales, i.e., preference for online social interaction - POSI, mood regulation, cognitive preoccupation, compulsive use, and negative outcomes) was administered to 815 young Italian adults. A Structural Equation Modeling analysis was used to test the theoretical model. POSI resulted to be a positive predictor of Facebook use for mood regulation and of deficient self-regulation; using Facebook for mood regulation was a positive predictor of deficient self-regulation; and deficient self-regulation was a positive predictor of negative outcomes of Facebook use. Of note, difficulties in self-regulating Facebook use was related more strongly to using Facebook for mood regulation than to preference for online social interaction. Similarly, using Facebook for mood regulation appears to have a greater impact than preference for online social interaction on negative outcomes of PFU. The obtained results support the feasibility of the model of generalized PIU in the context of PFU and suggest that mood regulation abilities may be a potential target for prevention and treatment of PFU.

Media exposure to terrorism and people's risk perception: The role of environmental sensitivity and psychophysiological response to stress.

Terrorist attacks have a destabilizing impact on the general population, causing distress and fear. However, not all individuals are equally susceptible to the effects of terror threat. This study aimed to examine whether exposure to terrorism-related pictures interacted with individual differences in environmental sensitivity and psychophysiological response to stress to explain people's risk perception, operationalized as perceived likelihood of a terrorist attack and willingness to trade off one's privacy to increase national security. Ninety-five university students were randomly assigned to one of two conditions (terrorism-related vs. neutral pictures). After watching the pictures, they answered questions concerning risk perception and completed questionnaires. Stress was induced by the Mannheim Multicomponent Stress Test, during which heart rate was recorded. Results showed that the perceived likelihood of future attacks was affected by the interaction between exposure to terrorism pictures and psychophysiological reactivity to stress, whereas willingness to trade off one's privacy to improve national security was influenced by the interaction between exposure to terrorism pictures and environmental sensitivity. The study suggests that individuals high in sensitivity and psychophysiological stress reactivity are particularly affected by terrorism-related pictures. Psychologists should direct their efforts to raise general awareness of the negative effects, especially for some people, of such media coverage.