Decreased reward-related brain function prospectively predicts increased substance use

The path from mood symptoms to substance use: A longitudinal examination in individuals with and at risk for bipolar spectrum disorders

BACKGROUND

Adolescent substance use poses a critical public health challenge, intertwined with risk-taking behavior, criminality, functional impairment, and comorbid mental and physical health issues. Adolescents with bipolar spectrum disorders (BSD) exhibit heightened susceptibility to substance use, necessitating a nuanced exploration of the bipolar-substance use relationship.

METHODS

This study addressed gaps in the literature by employing a prospective, longitudinal design with 443 Philadelphia-area adolescents, tracking BSD symptoms and substance use. We predicted that BSD symptoms would be associated with increases in substance use, and that these effects would be more pronounced for individuals with a BSD and those with high reward sensitivity.

RESULTS

Hypomanic symptoms predicted subsequent substance use, with a stronger association observed in individuals diagnosed with BSD. Contrary to expectations, depressive symptoms did not exhibit a similar relationship. Although the hypothesized moderating role of reward sensitivity was not supported, higher reward sensitivity predicted increased substance use.

LIMITATIONS

Symptoms and substance use are only captured for the month prior to each session due to the assessment timeline. This highlights the benefits of frequent assessments over a shorter time frame to monitor real-time changes. Alternative classification methods for reward sensitivity, such as brain or behavior-based assessments, might yield different results.

CONCLUSIONS

This study's contributions include evaluating substance use broadly, utilizing a longitudinal design for temporal clarity, and shifting the focus from substance use predicting mood symptoms to the inverse. The findings underscore the need for continued exploration of mood symptom predictors of substance use, emphasizing the role of reward sensitivity.

Trait reward sensitivity modulates connectivity with the temporoparietal junction and Anterior Insula during strategic decision making

Many decisions happen in social contexts such as negotiations, yet little is understood about how people balance fairness versus selfishness. Past investigations found that activation in brain areas involved in executive function and reward processing was associated with people offering less with no threat of rejection from their partner, compared to offering more when there was a threat of rejection. However, it remains unclear how trait reward sensitivity may modulate activation and connectivity patterns in these situations. To address this gap, we used task-based fMRI to examine the relation between reward sensitivity and the neural correlates of bargaining choices. Participants (N = 54) completed the Sensitivity to Punishment (SP)/Sensitivity to Reward (SR) Questionnaire and the Behavioral Inhibition System/Behavioral Activation System scales. Participants performed the Ultimatum and Dictator Games as proposers and exhibited strategic decisions by being fair when there was a threat of rejection, but being selfish when there was not a threat of rejection. We found that strategic decisions evoked activation in the Inferior Frontal Gyrus (IFG) and the Anterior Insula (AI). Next, we found elevated IFG connectivity with the Temporoparietal junction (TPJ) during strategic decisions. Finally, we explored whether trait reward sensitivity modulated brain responses while making strategic decisions. We found that people who scored lower in reward sensitivity made less strategic choices when they exhibited higher AI-Angular Gyrus connectivity. Taken together, our results demonstrate how trait reward sensitivity modulates neural responses to strategic decisions, potentially underscoring the importance of this factor within social and decision neuroscience.

Trait Reward Sensitivity Modulates Connectivity with the Temporoparietal Junction and Anterior Insula during Strategic Decision Making

Many decisions happen in social contexts such as negotiations, yet little is understood about how people balance fairness versus selfishness. Past investigations found that activation in brain areas involved in executive function and reward processing was associated with people offering less with no threat of rejection from their partner, compared to offering more when there was a threat of rejection. However, it remains unclear how trait reward sensitivity may modulate activation and connectivity patterns in these situations. To address this gap, we used task-based fMRI to examine the relation between reward sensitivity and the neural correlates of bargaining choices. Participants (N = 54) completed the Sensitivity to Punishment (SP)/Sensitivity to Reward (SR) Questionnaire and the Behavioral Inhibition System/Behavioral Activation System scales. Participants performed the Ultimatum and Dictator Games as proposers and exhibited strategic decisions by being fair when there was a threat of rejection, but being selfish when there was not a threat of rejection. We found that strategic decisions evoked activation in the Inferior Frontal Gyrus (IFG) and the Anterior Insula (AI). Next, we found elevated IFG connectivity with the Temporoparietal junction (TPJ) during strategic decisions. Finally, we explored whether trait reward sensitivity modulated brain responses while making strategic decisions. We found that people who scored lower in reward sensitivity made less strategic choices when they exhibited higher AI-Angular Gyrus connectivity. Taken together, our results demonstrate how trait reward sensitivity modulates neural responses to strategic decisions, potentially underscoring the importance of this factor within social and decision neuroscience.

Higher substance use is associated with low executive control neural activity and higher inflammation

Individuals with substance use problems show lower executive control and alterations in prefrontal brain systems supporting emotion regulation and impulse control. A separate literature suggests that heightened inflammation also increases risk for substance use, in part, through targeting brain systems involved in executive control. Research on neural and inflammatory signaling in substance use, however, has occurred in parallel. Drawing on recent neuroimmune network models, we used fMRI to examine the relationships between executive control-related brain activity (as elicited by an n-back working memory task), peripheral inflammation, as quantified by inflammatory cytokines and C-reactive protein (CRP), and substance use for the past month in 93 participants [mean age = 24.4 (SD = 0.6)]. We operationalized low executive control as a neural inefficiency during the n-back task to achieve normative performance, as reflected in higher working memory-related brain activity and lower activity in the default mode network (DMN). Consistent with prediction, individuals with low executive control and high inflammation reported more substance use over the past month, controlling for behavioral performance on the n-back, sex, time between assessments, body-mass-index (BMI), and personal socioeconomic status (SES) (interaction between inflammation and working memory-related brain activity, b = 0.210, p = 0.005; interaction between inflammation and DMN, b = -0.219, p < 0.001). Findings suggest that low executive control and high inflammation may be associated with higher substance use. This has implications for understanding psychological, neural, and immunological risk for substance use problems and the development of interventions to target each of these components.

Corticostriatal responses to social reward are linked to trait reward sensitivity and subclinical substance use in young adults

Aberrant levels of reward sensitivity have been linked to substance use disorder and are characterized by alterations in reward processing in the ventral striatum (VS). Less is known about how reward sensitivity and subclinical substance use relate to striatal function during social rewards (e.g. positive peer feedback). Testing this relation is critical for predicting risk for development of substance use disorder. In this pre-registered study, participants (N = 44) underwent fMRI while completing well-matched tasks that assess neural response to reward in social and monetary domains. Contrary to our hypotheses, aberrant reward sensitivity blunted the relationship between substance use and striatal activation during receipt of rewards, regardless of domain. Moreover, exploratory whole-brain analyses showed unique relations between substance use and social rewards in temporoparietal junction. Psychophysiological interactions demonstrated that aberrant reward sensitivity is associated with increased connectivity between the VS and ventromedial prefrontal cortex during social rewards. Finally, we found that substance use was associated with decreased connectivity between the VS and dorsomedial prefrontal cortex for social rewards, independent of reward sensitivity. These findings demonstrate nuanced relations between reward sensitivity and substance use, even among those without substance use disorder, and suggest altered reward-related engagement of cortico-VS responses as potential predictors of developing disordered behavior.

Annual Research Review: Neuroimmune network model of depression: a developmental perspective

Depression is a serious public health problem, and adolescence is an 'age of risk' for the onset of Major Depressive Disorder. Recently, we and others have proposed neuroimmune network models that highlight bidirectional communication between the brain and the immune system in both mental and physical health, including depression. These models draw on research indicating that the cellular actors (particularly monocytes) and signaling molecules (particularly cytokines) that orchestrate inflammation in the periphery can directly modulate the structure and function of the brain. In the brain, inflammatory activity heightens sensitivity to threats in the cortico-amygdala circuit, lowers sensitivity to rewards in the cortico-striatal circuit, and alters executive control and emotion regulation in the prefrontal cortex. When dysregulated, and particularly under conditions of chronic stress, inflammation can generate feelings of dysphoria, distress, and anhedonia. This is proposed to initiate unhealthy, self-medicating behaviors (e.g. substance use, poor diet) to manage the dysphoria, which further heighten inflammation. Over time, dysregulation in these brain circuits and the inflammatory response may compound each other to form a positive feedback loop, whereby dysregulation in one organ system exacerbates the other. We and others suggest that this neuroimmune dysregulation is a dynamic joint vulnerability for depression, particularly during adolescence. We have three goals for the present paper. First, we extend neuroimmune network models of mental and physical health to generate a developmental framework of risk for the onset of depression during adolescence. Second, we examine how a neuroimmune network perspective can help explain the high rates of comorbidity between depression and other psychiatric disorders across development, and multimorbidity between depression and stress-related medical illnesses. Finally, we consider how identifying neuroimmune pathways to depression can facilitate a 'next generation' of behavioral and biological interventions that target neuroimmune signaling to treat, and ideally prevent, depression in youth and adolescents.

Corticostriatal Responses to Social Reward are Linked to Trait Reward Sensitivity and Subclinical Substance Use in Young Adults

Aberrant levels of reward sensitivity have been linked to substance use disorder and are characterized by alterations in reward processing in the ventral striatum (VS). Less is known about how reward sensitivity and subclinical substance use relate to striatal function during social rewards (e.g., positive peer feedback). Testing this relation is critical for predicting risk for development of substance use disorder. In this pre-registered study, participants (N=44) underwent fMRI while completing well-matched tasks that assess neural response to reward in social and monetary domains. Contrary to our hypotheses, aberrant reward sensitivity blunted the relationship between substance use and striatal activation during receipt of rewards, regardless of domain. Moreover, exploratory whole-brain analyses showed unique relations between substance use and social rewards in temporoparietal junction. Psychophysiological interactions demonstrated that aberrant reward sensitivity is associated with increased connectivity between the VS and ventromedial prefrontal cortex during social rewards. Finally, we found that substance use was associated with decreased connectivity between the VS and dorsomedial prefrontal cortex for social rewards, independent of reward sensitivity. These findings demonstrate nuanced relations between reward sensitivity and substance use, even among those without substance use disorder, and suggest altered reward-related engagement of cortico-VS responses as potential predictors of developing disordered behavior.

Examination of reward processing dysfunctions in the left dorsal striatum and other brain regions among psychiatric inpatients with substance use

BACKGROUND

Substance misuse is a major public health issue and research has established attenuated reward responses to drug cues in those who misuse substances. Yet, little is known about whether the expectation of natural reinforcers engages distinct brain regions in substance misuse.

METHODS

Using functional magnetic resonance imaging (fMRI), we delivered juice at expected and unexpected times to examine reward processing dysfunctions. We focused on the responses within the left dorsal striatum (DS) in individuals with high-risk substance use (HRU, n = 65), low-risk substance use (psychiatric controls, PC, n = 65), and healthy controls (HC, n = 65). Additionally, we investigated whether the dysfunction in reward processing within the left DS is correlated with other common psychiatric symptoms. Finally, we conducted a comprehensive analysis of the whole brain to investigate other non-hypothesized brain regions.

RESULTS

Compared to HC, HRU displayed lower responses to juice delivery (i.e., reward) in the left DS (p <.05). The whole-brain analysis demonstrated that compared to HC, HRU displayed significantly lower responses to reward stimuli in various brain regions, including the bilateral caudate, temporal gyrus, left frontal gyrus, middle frontal gyrus, and right thalamus.

LIMITATIONS

Participants were individuals with polysubstance use; therefore, we were not able to examine the effects of individual substances.

CONCLUSIONS

Our findings suggest that HRU displays lower responses to reward stimuli within the left DS and other non-hypothesized brain regions. Our findings may help further elucidate reward processing dysfunctions related to substance misuse.

Developmental Changes in Habenular and Striatal Social Reinforcement Responsivity Across Adolescence Linked With Substance Use

BACKGROUND

Habenula (HB) function is implicated in substance use disorders and is involved in inhibiting dopamine release in the ventral striatum (VS). While blunted VS reward responsivity is implicated in risk for later substance use, links between HB reinforcement processing and progression of use have not, to our knowledge, been examined among adolescents. In the present study, we longitudinally assessed HB and VS responsivity to social rewards and punishments across adolescence and examined associations with substance use.

METHODS

Within a longitudinal design, 170 adolescents (53.5% female) completed 1 to 3 functional magnetic resonance imaging scans across 6th to 9th grade and reported yearly substance use across 6th to 11th grade. We examined VS and HB responsivity to social reinforcement during a social incentive delay task in which adolescents received social rewards (smiling faces) and punishments (scowling faces).

RESULTS

We observed increased VS responsivity to social rewards (vs. reward omissions) and increased VS, but decreased HB, responsivity to social punishment avoidance versus receipt. However, contrary to hypotheses, the HB displayed increased responsivity to social rewards (vs. reward omissions). Further, adolescents reporting regular substance use displayed longitudinally declining HB responsivity to social rewards (vs. reward omissions), whereas adolescents reporting no substance use displayed longitudinally increasing HB responsivity. In contrast, whereas VS responsivity to punishment avoidance versus receipt increased longitudinally among regular substance users, it stayed relatively stable among nonusers.

CONCLUSIONS

These results suggest that differential HB and VS social reinforcement processing trajectories across adolescence are associated with substance use.

Neurological, Behavioral, and Pathophysiological Characterization of the Co-Occurrence of Substance Use and HIV: A Narrative Review

Combined antiretroviral therapy (cART) has greatly reduced the severity of HIV-associated neurocognitive disorders in people living with HIV (PLWH); however, PLWH are more likely than the general population to use drugs and suffer from substance use disorders (SUDs) and to exhibit risky behaviors that promote HIV transmission and other infections. Dopamine-boosting psychostimulants such as cocaine and methamphetamine are some of the most widely used substances among PLWH. Chronic use of these substances disrupts brain function, structure, and cognition. PLWH with SUD have poor health outcomes driven by complex interactions between biological, neurocognitive, and social factors. Here we review the effects of comorbid HIV and psychostimulant use disorders by discussing the distinct and common effects of HIV and chronic cocaine and methamphetamine use on behavioral and neurological impairments using evidence from rodent models of HIV-associated neurocognitive impairments (Tat or gp120 protein expression) and clinical studies. We also provide a biopsychosocial perspective by discussing behavioral impairment in differentially impacted social groups and proposing interventions at both patient and population levels.

Parsing patterns of reward responsiveness: Initial evidence from latent profile analysis

Variation in reward responsiveness has been linked to psychopathology. Reward responsiveness is a complex phenomenon that encompasses different temporal dimensions (i.e., reward anticipation or consumption) that can be measured using multiple appetitive stimuli. Furthermore, distinct measures, such as neural and self-report measures, reflect related but distinct aspects of reward responsiveness. To understand reward responsiveness more comprehensively and better identify deficits in reward responsiveness implicated in psychopathology, we examined ways multiple measures of reward responsiveness jointly contribute to distinct psychological problems by using latent profile analysis. Specifically, we identified three profiles of reward responsiveness among 139 female participants based on their neural responses to money, food, social acceptance, and erotic images and self-reported responsiveness to reward anticipation and consumption. Profile 1 (n = 30) exhibited blunted neural responses to social rewards and erotic images, low self-reported reward responsiveness, but average neural responses to monetary and food rewards. Profile 2 (n = 71) showed elevated neural response to monetary rewards, average neural responses to other stimuli, and average self-reported reward responsiveness. Profile 3 (n = 38) showed more variable neural responses to reward (e.g., hypersensitivity to erotic images, hyposensitivity to monetary rewards), and high self-reported reward responsiveness. These profiles were differentially associated with variables generally linked to aberrations in reward responsiveness. For example, Profile 1 was most strongly associated with anhedonic depression and social dysfunction, whereas Profile 3 was associated with risk-taking behaviors. These preliminary findings may help to elucidate ways different measures of reward responsiveness manifest within and across individuals and identify specific vulnerabilities for distinct psychological problems.

Predictors of polysubstance use in patients with severe alcohol use disorder: the role of reward craving

BACKGROUND

Different craving typologies (i.e., reward, relief, obsessive) have been identified in alcohol use disorder (AUD) but have been less investigated in specific populations like AUD patients with polysubstance use (PSU). The role of dysfunctional personality traits and reward pathways has been reported in both AUD and PSU. We hypothesized that patients with AUD-PSU might show a prevalent reward craving, alongside specific sociodemographic, clinical, and personality features, and aimed at investigating differences in 423 severe AUD outpatients with and without PSU.

METHODS

One hundred fifteen patients (27.1% of the sample, 67% males, 42 ± 11.6 years old) displayed PSU. Sociodemographic, clinical features and psychopathological/personality dimensions were assessed through: Craving Typologies Questionnaire (CTQ); Obsessive-Compulsive Drinking Scale (OCDS); UPPS-P Impulsive Behavior Scale (S-UPPS-P); Difficulties in Emotion Regulation Scale (DERS). A binomial logistic regression explored factors associated with PSU.

RESULTS

We found higher CTQ 'reward' scores (p < 0.001) in AUD-PSU patients, and a significant association between reward craving and PSU through logistic regression (OR:1.13; p = 0.005). Earlier AUD onset (p < 0.001), greater rates of binge drinking (p = 0.029), more legal problems (p = 0.015), but no significantly higher S-UPPS-S and DERS scores, were detected in AUD-PSU patients.

CONCLUSIONS

Reward craving was associated with increased risk for PSU in severe AUD patients. Given AUD-PSU participants greater severity and detrimental treatment responses imputed to PSU, identifying prevalent craving types among risk factors for PSU in AUD may help to implement therapeutic strategies. Addressing neurobiological and behavioral mechanisms through combined psychotherapies, pharmacological and neuromodulation treatments could support tailored interventions with better long-term outcome.

Circadian, Reward, and Emotion Systems in Teens prospective longitudinal study: protocol overview of an integrative reward-circadian rhythm model of first onset of bipolar spectrum disorder in adolescence

BACKGROUND

Bipolar spectrum disorders (BSDs) are associated with a heightened sensitivity to rewards and elevated reward-related brain function in cortico-striatal circuitry. A separate literature documents social and circadian rhythm disruption in BSDs. Recently, integrated reward-circadian models of BSDs have been proposed. These models draw on work indicating that the two systems influence each other and interact to affect mood functioning. When dysregulated, reward and circadian system signaling may combine to form a positive feedback loop, whereby dysregulation in one system exacerbates dysregulation in the other. Project CREST (Circadian, Reward, and Emotion Systems in Teens) provides a first systematic test of reward-circadian dysregulation as a synergistic and dynamic vulnerability for first onset of BSD and increases in bipolar symptoms during adolescence.

METHODS

This NIMH-funded R01 study is a 3-year prospective, longitudinal investigation of approximately 320 community adolescents from the broader Philadelphia area, United States of America. Eligible participants must be 13-16 years old, fluent in English, and without a prior BSD or hypomanic episode. They are being selected along the entire dimension of self-reported reward responsiveness, with oversampling at the high tail of the dimension in order to increase the likelihood of BSD onsets. At Times 1-6, every 6 months, participants will complete assessments of reward-relevant and social rhythm disruption life events and self-report and diagnostic assessments of bipolar symptoms and episodes. Yearly, at Times 1, 3, and 5, participants also will complete self-report measures of circadian chronotype (morningness-eveningness) and social rhythm regularity, a salivary dim light melatonin onset (DLMO) procedure to assess circadian phase, self-report, behavioral, and neural (fMRI) assessments of monetary and social reward responsiveness, and a 7-day ecological momentary assessment (EMA) period. During each EMA period, participants will complete continuous measures of sleep/wake and activity (actigraphy), a daily sleep diary, and three within-day (morning, afternoon, evening) measures of life events coded for reward-relevance and social rhythm disruption, monetary and social reward responsiveness, positive and negative affect, and hypo/manic and depressive symptoms. The fMRI scan will occur on the day before and the DLMO procedure will occur on the first evening of the 7-day EMA period.

DISCUSSION

This study is an innovative integration of research on multi-organ systems involved in reward and circadian signaling in understanding first onset of BSD in adolescence. It has the potential to facilitate novel pharmacological, neural, and behavioral interventions to treat, and ideally prevent, bipolar conditions.

Reward and Immune Systems in Emotion (RISE) prospective longitudinal study: Protocol overview of an integrative reward-inflammation model of first onset of major depression in adolescence

Background

Depression is associated with a reduced sensitivity to rewards and low reward-related brain function in cortico-striatal circuitry. A separate literature documents elevated peripheral inflammation in depression. Recently, integrated reward-inflammation models of depression have been proposed. These models draw on work indicating that peripheral inflammatory proteins access the brain, where they lower reward responsiveness. This blunted reward responsiveness is proposed to initiate unhealthy behaviors (substance use, poor diet), as well as sleep disruption and stress generation, which further heighten inflammation. Over time, dysregulation in reward responsiveness and immune signaling may synergize in a positive feedback loop, whereby dysregulation in each system exacerbates dysregulation in the other. Project RISE (Reward and Immune Systems in Emotion) provides a first systematic test of reward-immune dysregulation as a synergistic and dynamic vulnerability for first onset of major depressive disorder and increases in depressive symptoms during adolescence.

Methods

This NIMH-funded R01 study is a 3-year prospective, longitudinal investigation of approximately 300 community adolescents from the broader Philadelphia area, United States of America. Eligible participants must be 13-16 years old, fluent in English, and without a prior major depressive disorder. They are being selected along the entire dimension of self-reported reward responsiveness, with oversampling at the low tail of the dimension in order to increase the likelihood of major depression onsets. At Time 1 (T1), T3, and T5, each a year apart, participants complete blood draws to quantify biomarkers of low-grade inflammation, self-report and behavioral measures of reward responsiveness, and fMRI scans of reward neural activity and functional connectivity. At T1-T5 (with T2 and T4 six months between the yearly sessions), participants also complete diagnostic interviews and measures of depressive symptoms, reward-relevant life events, and behaviors that increase inflammation. Adversity history is assessed at T1 only.

Discussion

This study is an innovative integration of research on multi-organ systems involved in reward and inflammatory signaling in understanding first onset of major depression in adolescence. It has the potential to facilitate novel neuroimmune and behavioral interventions to treat, and ideally prevent, depression.

The differential neural substrates for reward choice under gain-loss contexts and risk in alcohol use disorder: Evidence from a voxel-based meta-analysis

BACKGROUND

Making a risky decision is a complex process that involves the evaluation of both the values of the options and the associated risk level; this process is distinct from reward processing in gain versus loss contexts. Although disrupted reward processing in mesolimbic dopamine circuitry is suggested to underlie pathological incentive processing in patients with alcohol use disorder (AUD), the differential neural processes subserving these motivational tendencies for risk situations or gain/loss choices in decision-making have not been identified.

METHODS

To examine the common or distinct neural mechanisms in the evaluation of risk versus outcomes for AUD, we conducted two separate coordinate-based meta-analyses of functional neuroimaging studies by using Seed-Based d Mapping software to evaluate 13 studies investigating gain and loss processing and 10 studies investigating risky decision-making.

RESULTS

During gain and loss processing, relative to healthy controls, AUD patients showed reduced activation in the mesocortical-limbic circuit, including the orbital prefrontal cortex (OFC), dorsal striatum, insula, hippocampus, cerebellum, cuneus cortex and superior temporal gyrus, but hyperactivation in the inferior temporal gyrus and paracentral lobule (extending to the middle cingulate cortex (MCC) and precuneus). During decision-making under risk, AUD patients exhibited hypoactivity of the prefrontal and cingulate cortices, including the posterior cingulate cortex (extending to the MCC), middle frontal gyrus, medial prefrontal cortex, dorsolateral prefrontal cortex, OFC and anterior cingulate cortex.

CONCLUSIONS

Our results extend existing neurological evidence by showing that a reduced response in the mesocortical-limbic circuit is found in gain versus loss processing, with decreased responsivity in cortical regions in risk decision-making. Our results implicate dissociable neural circuit responses for gain-loss processing and risk decision-making, which contribute to a better understanding of the pathophysiological mechanism underlying nondrug incentive and risk processing in individuals with AUD.

Psychosocial Basis of Human Sufferings and Poverty in Patients with Neurological and Psychiatric Disorders

Neurological disorders and psychiatric ailments often lead to cognitive disabilities and low attainment of education, pivoting misconceptions, myths, and misbeliefs. Poverty and low educational attainment are intriguingly associated with poor awareness and perception of these diseases that add to the suffering. Poverty goes parallel with a low level of education and is intricately associated with neuropsychiatric ailments, which have the potential to spread transgenerationally. Robust education policies, proper government rules and regulations against the spread of disease-related myths and misconceptions, uplifting medical education in its true sense, voices against consanguinity, and programs to raise scientific perception about diseases can help to throw light at the end of this dark tunnel. In this article, the authors intend to 1) decipher the potential psychosocial basis of human suffering and poverty in patients with neurological and psychiatric disorders, and 2) discuss the apropos way-outs that would potentially mitigate suffering, and alleviate the economic burden and cognitive disabilities of families with neuropsychiatric diseases.

Fear of missing out (FOMO) associates with reduced cortical thickness in core regions of the posterior default mode network and higher levels of problematic smartphone and social media use

BACKGROUND AND AIMS

Fear of missing out (FOMO) promotes the desire or urge to stay continuously connected with a social reference group and updated on their activities, which may result in escalating and potentially addictive smartphone and social media use. The present study aimed to determine whether the neurobiological basis of FOMO encompasses core regions of the reward circuitry or social brain, and associations with levels of problematic smartphone or social media use.

METHODS

We capitalized on a dimensional neuroimaging approach to examine cortical thickness and subcortical volume associations in a sample of healthy young individuals (n = 167). Meta-analytic network and behavioral decoding analyses were employed to further characterize the identified regions.

RESULTS

Higher levels of FOMO associated with lower cortical thickness in the right precuneus. In contrast, no associations between FOMO and variations in striatal morphology were observed. Meta-analytic decoding revealed that the identified precuneus region exhibited a strong functional interaction with the default mode network (DMN) engaged in social cognitive and self-referential domains.

DISCUSSION AND CONCLUSIONS

Together the present findings suggest that individual variations in FOMO are associated with the brain structural architecture of the right precuneus, a core hub within a large-scale functional network resembling the DMN and involved in social and self-referential processes. FOMO may promote escalating social media and smartphone use via social and self-referential processes rather than reward-related processes per se.