Dynamic Causal Modeling of Insular, Striatal, and Prefrontal Cortex Activities During a Food-Specific Go/NoGo Task

Increased ventral anterior insular connectivity to sports betting availability indexes problem gambling

With the advent of digital technologies, online sports betting is spurring a fast-growing expansion. In this study, we examined how sports betting availability modulates the brain connectivity of frequent sports bettors with [problem bettors (PB)] or without [non-problem bettors (NPB)] problematic sports betting. We conducted functional connectivity analyses centred on the ventral anterior insular cortex (vAI), a brain region playing a key role in the dynamic interplay between reward-based processes. We re-analysed a dataset on sports betting availability undertaken in PB (n = 30) and NPB (n = 35). Across all participants, we observed that sports betting availability elicited positive vAI coupling with extended clusters of brain activation (encompassing the putamen, cerebellum, occipital, temporal, precentral and central operculum regions) and negative vAI coupling with the orbitofrontal cortex. Between-group analyses showed increased positive vAI coupling in the PB group, as compared with the NPB group, in the left lateral occipital cortex, extending to the left inferior frontal gyrus, the anterior cingulate gyrus and the right frontal pole. Taken together, these results are in line with the central assumptions of triadic models of addictions, which posit that the insular cortex plays a pivotal role in promoting the drive and motivation to get a reward by 'hijacking' goal-oriented processes toward addiction-related cues. Taken together, these findings showed that vAI functional connectivity is sensitive not only to gambling availability but also to the status of problematic sport betting.

Heightened sensitivity to high-calorie foods in children at risk for obesity: insights from behavior, neuroimaging, and genetics

Pediatric obesity is a major public health concern. Genetic susceptibility and increased availability of energy-dense food are known risk factors for obesity. However, the extent to which these factors jointly bias behavior and neural circuitry towards increased adiposity in children remains unclear. While undergoing fMRI, 108 children (ages 5-11y) performed a food-specific go/no-go task. Participants were instructed to either respond ("go") or inhibit responding ("no-go") to images of food or toys. Half of the runs depicted high-calorie foods (e.g., pizza) whereas the other half depicted low-calorie foods (e.g., salad). Children were also genotyped for a DNA polymorphism associated with energy intake and obesity (FTO rs9939609) to examine the influence of obesity risk on behavioral and brain responses to food. Participants demonstrated differences in behavioral sensitivity to high- and low-calorie food images depending on task demands. Participants were slower but more accurate at detecting high- (relative to low-) calorie foods when responding to a neutral stimulus (i.e., toys) and worse at detecting toys when responding to high-calorie foods. Inhibition failures were accompanied by salience network activity (anterior insula, dorsal anterior cingulate cortex), which was driven by false alarms to food images. Children at a greater genetic risk for obesity (dose-dependent model of the FTO genotype) demonstrated pronounced brain and behavioral relationships such that genetic risk was associated with heightened sensitivity to high-calorie food images and increased anterior insula activity. These findings suggest that high-calorie foods may be particularly salient to children at risk for developing eating habits that promote obesity.

How images of food become cravingly salient in obesity

OBJECTIVE

This case-control study was aimed at testing two main hypotheses: (i) obesity is characterized by neurofunctional alterations within the mesocorticolimbic reward system, a brain network originating from the midbrain ventral tegmental area (VTA); and (ii) these alterations are associated with a bias for food-related stimuli and craving.

METHODS

Normal-weight individuals and individuals with obesity underwent a resting-state functional magnetic resonance imaging scan and the assessment of impulsivity, food craving, appetite, and implicit bias for food and non-food stimuli. The VTA was used as a seed to map, for each participant, the strength of its functional connections with the rest of the brain. The between-group difference in functional connectivity was then computed, and brain-behavior correlations were performed.

RESULTS

Individuals with obesity showed hyper-connectivity of the VTA with part of the ventral occipitotemporal cortex, recently found to be specialized for food images, and hypo-connectivity with the left inferior frontal gyrus, devoted to cognitive control. VTA-ventral occipitotemporal cortex connectivity was positively associated with food craving and food-related bias; the reverse correlation was observed for VTA-inferior frontal gyrus connectivity.

CONCLUSIONS

These findings reveal that, in obesity, food-related visual stimuli become cravingly salient through an imbalanced connectivity of the reward system with sensory-specific regions and the frontal cortex involved in cognitive control.

State-specific alterations in the neural computations underlying inhibitory control in women remitted from bulimia nervosa

The neurocomputational processes underlying bulimia nervosa and its primary symptoms, out-of-control overeating and purging, are poorly understood. Research suggests that the brains of healthy individuals form a dynamic internal model to predict whether control is needed in each moment. This study tested the hypothesis that this computational process of inhibitory control is abnormally affected by metabolic state (being fasted or fed) in bulimia nervosa. A Bayesian ideal observer model was fit to behavioral data acquired from 22 women remitted from bulimia nervosa and 20 group-matched controls who completed a stop-signal task during two counterbalanced functional MRI sessions, one after a 16 h fast and one after a meal. This model estimates participants' trial-by-trial updating of the probability of a stop signal based on their experienced trial history. Neural analyses focused on control-related Bayesian prediction errors, which quantify the direction and degree of "surprise" an individual experiences on any given trial. Regardless of group, metabolic state did not affect behavioral performance on the task. However, metabolic state modulated group differences in neural activation. In the fed state, women remitted from bulimia nervosa had attenuated prediction-error-dependent activation in the left dorsal caudate. This fed-state activation was lower among women with more frequent past binge eating and self-induced vomiting. When they are in a fed state, individuals with bulimia nervosa may not effectively process unexpected information needed to engage inhibitory control. This may explain the difficulties these individuals have stopping eating after it begins.

The neural correlates of value representation: From single items to bundles

One of the core questions in Neuro-economics is to determine where value is represented. To date, most studies have focused on simple options and identified the ventromedial prefrontal cortex (VMPFC) as the common value region. We report the findings of an fMRI study in which we asked participants to make pairwise comparisons involving options of varying complexity: single items (Control condition), bundles made of the same two single items (Scaling condition) and bundles made of two different single items (Bundling condition). We construct a measure of choice consistency to capture how coherent the choices of a participant are with one another. We also record brain activity while participants make these choices. We find that a common core of regions involving the left VMPFC, the left dorsolateral prefrontal cortex (DLPFC), regions associated with complex visual processing and the left cerebellum track value across all conditions. Also, regions in the DLPFC, the ventrolateral prefrontal cortex (VLPFC) and the cerebellum are differentially recruited across conditions. Last, variations in activity in VMPFC and DLPFC value-tracking regions are associated with variations in choice consistency. This suggests that value based decision-making recruits a core set of regions as well as specific regions based on task demands. Further, correlations between consistency and the magnitude of signal change with lateral portions of the PFC suggest the possibility that activity in these regions may play a causal role in decision quality.

Theoretical conceptualization of online privacy-related decision making – Introducing the tripartite self-disclosure decision model

Self-disclosures on online social networks have received increased attention in the last two decades. Researchers from different disciplines investigated manifold influencing variables, and studies applied different theories to explain why many users share very sensitive and personal information despite potential risks and negative consequences, whereas others do not. Oftentimes, it is argued that self-disclosure decisions result from a kind of rational “calculus” of risks and benefits. However, such an assumption of rationality can and has been criticized. Nevertheless, fundamental cognitive and affective mechanisms that underlie self-disclosure decision making on social networks are still under-explored. By building upon previous self-disclosure theories and models, dual-and tripartite-system perspectives of decision making, and former empirical findings, we propose a Tripartite Self-Disclosure Decision (TSDD) model that conceptualizes inner processes of online self-disclosure decision making. Central to this model is the proposed interaction of three neural and cognitive/affective systems: a reflective, an impulsive, and an interoceptive system. We further highlight individual and environmental features, which can impact individuals’ online self-disclosure decisions by (interactively) influencing the proposed inner decision-making processes targeting the aforementioned three systems. Possible short- and long-term consequences are also discussed, which in turn can affect certain model components in subsequent self-disclosure decision situations. By taking such a neurocognitive perspective, we expand current research and models, which helps to better understand potentially risky information sharing on online social networks and can support attempts to prevent users from incautious self-disclosures.

Functional connectivity gradients of the insula to different cerebral systems

The diverse functional roles of the insula may emerge from its heavy connectivity to an extensive network of cortical and subcortical areas. Despite several previous attempts to investigate the hierarchical organization of the insula by applying the recently developed gradient approach to insula-to-whole brain connectivity data, little is known about whether and how there is variability across connectivity gradients of the insula to different cerebral systems. Resting-state functional MRI data from 793 healthy subjects were used to discover and validate functional connectivity gradients of the insula, which were computed based on its voxel-wise functional connectivity profiles to distinct cerebral systems. We identified three primary patterns of functional connectivity gradients of the insula to distinct cerebral systems. The connectivity gradients to the higher-order transmodal associative systems, including the prefrontal, posterior parietal, temporal cortices, and limbic lobule, showed a ventroanterior-dorsal axis across the insula; those to the lower-order unimodal primary systems, including the motor, somatosensory, and occipital cortices, displayed radiating transitions from dorsoanterior toward both ventroanterior and dorsoposterior parts of the insula; the connectivity gradient to the subcortical nuclei exhibited an organization along the anterior-posterior axis of the insula. Apart from complementing and extending previous literature on the heterogeneous connectivity patterns of insula subregions, the presented framework may offer ample opportunities to refine our understanding of the role of the insula in many brain disorders.

Improved food Go/No-Go scores after transcranial direct current stimulation (tDCS) to prefrontal cortex in a randomized trial

OBJECTIVE

Reduced dorsolateral prefrontal cortex (dlPFC) activity and inhibitory control may contribute to obesity. The study objective was to assess effects of repeated transcranial direct current stimulation (tDCS) on food Go/No-Go (GNG), food Stroop performance, and snack food intake.

METHODS

Twenty-nine individuals with obesity (12 male; mean [SD], age 42 [11] years; BMI 39 [8]) participated in a combined inpatient/outpatient randomized parallel-design trial and received 15 sessions of anodal or sham tDCS to the left dlPFC. Food-related inhibitory control (GNG), attentional bias (Stroop), and snack food intake were assessed at baseline, completion of inpatient sessions (day 7), and follow-up (day 31).

RESULTS

GNG performance improved in the anodal group by day 31, compared with sham (p = 0.01), but Stroop scores did not differ by intervention. Greater snack food intake was associated with lower GNG scores (p = 0.01), driven by the sham group (p < 0.001) and higher food and palatable bias scores on the Stroop (all p = 0.02) across both groups. Changes on tasks were not associated with changes in intake.

CONCLUSIONS

Anodal tDCS to the left dlPFC improved performance on a food-related inhibitory control task, providing evidence of potential for therapeutic benefit of neuromodulation in areas controlling executive function. Results showed that tDCS to the dlPFC reduced snack food intake and hunger; however, underlying neurocognitive mechanisms remain uncertain.

Task-Dependent Effective Connectivity of the Reward Network During Food Cue-Reactivity: A Dynamic Causal Modeling Investigation

Neural reactivity to food cues may play a central role in overeating and excess weight gain. Functional magnetic resonance imaging (fMRI) studies have implicated regions of the reward network in dysfunctional food cue-reactivity, but neural interactions underlying observed patterns of signal change remain poorly understood. Fifty overweight and obese participants with self-reported cue-induced food craving viewed food and neutral cues during fMRI scanning. Regions of the reward network with significantly greater food versus neutral cue-reactivity were used to specify plausible models of task-related neural interactions underlying the observed blood oxygenation level-dependent (BOLD) signal, and a bi-hemispheric winning model was identified in a dynamic causal modeling (DCM) framework. Neuro-behavioral correlations are investigated with group factor analysis (GFA) and Pearson's correlation tests. The ventral tegmental area (VTA), amygdalae, and orbitofrontal cortices (OFC) showed significant food cue-reactivity. DCM suggests these activations are produced by largely reciprocal dynamic signaling between these regions, with food cues causing regional disinhibition and an apparent shifting of activity to the right amygdala. Intrinsic self-inhibition in the VTA and right amygdala is negatively correlated with measures of food craving and hunger and right-amygdalar disinhibition by food cues is associated with the intensity of cue-induced food craving, but no robust cross-unit latent factors were identified between the neural group and behavioral or demographic variable groups. Our results suggest a rich array of dynamic signals drive reward network cue-reactivity, with the amygdalae mediating much of the dynamic signaling between the VTA and OFCs. Neuro-behavioral correlations suggest particularly crucial roles for the VTA, right amygdala, and the right OFC-amygdala connection but the more robust GFA identified no cross-unit factors, so these correlations should be interpreted with caution. This investigation provides novel insights into dynamic circuit mechanisms with etiologic relevance to obesity, suggesting pathways in biomarker development and intervention.

“Sound” Decisions: The Combined Role of Ambient Noise and Cognitive Regulation on the Neurophysiology of Food Cravings

Our ability to evaluate long-term goals over immediate rewards is manifested in the brain’s decision circuit. Simplistically, it can be divided into a fast, impulsive, reward “system 1” and a slow, deliberate, control “system 2.” In a noisy eating environment, our cognitive resources may get depleted, potentially leading to cognitive overload, emotional arousal, and consequently more rash decisions, such as unhealthy food choices. Here, we investigated the combined impact of cognitive regulation and ambient noise on food cravings through neurophysiological activity. Thirty-seven participants were recruited for an adapted version of the Regulation of Craving (ROC) task. All participants underwent two sessions of the ROC task; once with soft ambient restaurant noise (∼50 dB) and once with loud ambient restaurant noise (∼70 dB), while data from electroencephalography (EEG), electrodermal activity (EDA), and self-reported craving were collected for all palatable food images presented in the task. The results indicated that thinking about future (“later”) consequences vs. immediate (“now”) sensations associated with the food decreased cravings, which were mediated by frontal EEG alpha power. Likewise, “later” trials also increased frontal alpha asymmetry (FAA) —an index for emotional motivation. Furthermore, loud (vs. soft) noise increased alpha, beta, and theta activity, but for theta activity, this was solely occurring during “later” trials. Similarly, EDA signal peak probability was also higher during loud noise. Collectively, our findings suggest that the presence of loud ambient noise in conjunction with prospective thinking can lead to the highest emotional arousal and cognitive load as measured by EDA and EEG, respectively, both of which are important in regulating cravings and decisions. Thus, exploring the combined effects of interoceptive regulation and exteroceptive cues on food-related decision-making could be methodologically advantageous in consumer neuroscience and entail theoretical, commercial, and managerial implications.

The Hunger Games: Homeostatic State-Dependent Fluctuations in Disinhibition Measured with a Novel Gamified Test Battery

Food homeostatic states (hunger and satiety) influence the cognitive systems regulating impulsive responses, but the direction and specific mechanisms involved in this effect remain elusive. We examined how fasting, and satiety, affect cognitive mechanisms underpinning disinhibition using a novel framework and a gamified test-battery. Thirty-four participants completed the test-battery measuring three cognitive facets of disinhibition: attentional control, information gathering and monitoring of feedback, across two experimental sessions: one after overnight fasting and another after a standardised meal. Homeostatic state was assessed using subjective self-reports and biological markers (i.e., blood-derived liver-expressed antimicrobial protein 2 (LEAP-2), insulin and leptin). We found that participants who experienced greater subjective hunger during the satiety session were more impulsive in the information gathering task; results were not confounded by changes in mood or anxiety. Homeostatic state did not significantly influence disinhibition mechanisms linked to attentional control or feedback monitoring. However, we found a significant interaction between homeostatic state and LEAP-2 on attentional control, with higher LEAP-2 associated with faster reaction times in the fasted condition only. Our findings indicate lingering hunger after eating increases impulsive behaviour via reduced information gathering. These findings identify a novel mechanism that may underpin the tendency to overeat and/or engage in broader impulsive behaviours.

Diminished prefrontal cortex activation in patients with binge eating disorder associates with trait impulsivity and improves after impulsivity-focused treatment based on a randomized controlled IMPULS trial

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Persons with binge eating disorder show increased impulsivity.

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We investigated cognitive control to food cues using fNIRS.

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Compared to healthy controls, binge eaters show weaker activation of the prefrontal cortex.

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After behavioral therapy, binge eaters increase prefrontal cortex activation.

Background

Behavioral and cognitive control are vital for healthy eating behavior. Patients with binge eating disorder (BED) suffer under recurrent binge eating episodes accompanied by subjective loss of control that results, among other factors, from increased impulsivity.

Methods

In the current study, we investigated the frontal network using functional near-infrared spectroscopy (fNIRS) during a food specific go/nogo task to assess response inhibition in 24 patients with BED (BMI range 22.6–59.7 kg/m²) compared to 12 healthy controls (HC) (BMI range 20.9–27 kg/m²). Patients with BED were invited to undergo fNIRS measurements before an impulsivity-focused cognitive behavioral group treatment, directly after this treatment and 3 months afterwards. As this was a planned subgroup analysis of the randomized controlled IMPULS trial, patients with BED were randomized either to the treatment group (n = 14) or to a control group (n = 10). The treatment group received 8 weekly sessions of the IMPULS treatment.

Results

We found a significant response inhibition effect (nogo minus go), in terms of an increased oxygenated hemoglobin response in the bilateral prefrontal cortex in both groups. The greatest response was observed when participants were instructed to go for healthy and withhold their response to unhealthy high caloric food cues. The healthy nogo condition failed to show a significant prefrontal inhibitory response, which was probably related to the task design, as the condition was considered more demanding. BED patients, especially those with higher trait impulsivity, showed a weaker activation of the prefrontal cortex during response inhibition, predominantly in the right hemisphere. Interestingly, three months after the treatment, patients of the treatment group increased their right prefrontal cortex activity during response inhibition. Likewise, increased prefrontal cortex activation correlated with decreased trait impulsivity after treatment.

Conclusions

Our results suggest that patients with BED have limited resources to activate the prefrontal cortex when asked to inhibit a reaction onto food-specific stimuli. However, this effect could be partly driven by differences in BMI between the HC and BED group. Cognitive-behavioral therapy targeting impulsive eating behavior may improve prefrontal cortex recruitment during response inhibition.

The Relationship between Overweight/Obesity and Executive Control in College Students: The Mediating Effect of BDNF and 5-HT

The main aim of this study was to explore the association between overweight/obesity and executive control (EC) in young adults, and to further analyze the mediating effect of brain-derived neurotrophic factor (BDNF) and serotonin (5-hydroxytryptamine (5-HT)) on the relationship between overweight/obesity and EC. A total of 449 college students aged between 18 and 20 years were recruited for the study between March and December 2019. Their height and weight were then measured professionally. Subsequently, body mass index (BMI) was calculated as weight (kg) divided by the square of height (m). The EC of the participants was then estimated using the Flanker task, while their serum BDNF levels and 5-HT levels were measured using an enzyme-linked immunosorbent assay (ELISA) kit. Finally, the multiple intermediary models in SPSS were used to analyze the mediating effect of 5-HT and BDNF between overweight/obesity and EC. The result show that the overweight/obesity of college students was positively correlated with the response of EC (p ≤ 0.005). However, it was negatively correlated with BDNF (p ≤ 0.05) and 5-HT (p ≤ 0.05). Moreover, BDNF (p ≤ 0.001) and 5-HT (p ≤ 0.001) were negatively correlated with the response of EC. The BDNF level played a partial mediating role between overweight/obesity and EC that accounted for 7.30% of the total effect value. Similarly, the 5-HT of college students played a partial mediating role between overweight/obesity and EC that accounted for 8.76% of the total effect value. Gender and age had no regulatory effect on the relationship between overweight/obesity, BDNF, 5-HT, and EC. This study provides the evidence that 5-HT and BDNF mediated the association between overweight/obesity and executive control. It is indicated that 5-HT and BDNF might be the biological pathways underpinning the link between overweight/obesity and executive control.

The role of the insula in internet gaming disorder

Internet gaming disorder (IGD) is a concerning issue that requires further research. Here, we seek to examine its neural etiology with an emphasis on the role of the insula. To do so, we relied on the tripartite neurocognitive model of addictive behaviors as applied to IGD. We hypothesized that (a) video game cues will elicit stronger reward system activation and weaker prefrontal activation in gamers vs controls, (b) the IGD scores of gamers will be positively associated with activation of the reward system and negatively with activation of prefrontal regions, (c) deprivation from video gaming will result in increased activation of the insula, when gamers are exposed to video game cues vs to neutral cues, and (d) in deprivation conditions, there will be positive and negative coupling, respectively, between activation of the insula and the reward and prefrontal regions in gamers. We tested these hypotheses with a design with one between-subjects factor (gamers vs controls) and two within-subjects factors: stimuli (gaming vs neutral; for all participants) and session (deprivation vs satiety; only for gamers). Findings based on functional magnetic resonance imaging (fMRI; applied to all 52 subjects, 26 gamers, and 26 controls) and psychophysiological interaction (PPI; applied to the 26 gamers) engaged in a video reactivity task supported our assertions. The IGD score positively correlated with activity in the right ventral striatum and negatively with activity in the right dorsolateral prefrontal cortex (DLPFC). Left insular cortex activity was the highest when observing video gaming cues under deprivation. Lastly, there was an increased coupling between the left insula and left ventral striatum and a decreased coupling with left DLPFC when observing video gaming cues compared with when watching control videos in the deprivation condition.

The ups and downs of relating nondrug reward activation to substance use risk in adolescents

Purpose of review

A wealth of epidemiological and cohort research, together with a healthy dose of anecdote, has characterized late-adolescence and emerging adulthood as a time of increased substance use and other risky behaviors. This review will address whether differences between adolescents or between adolescents and other age groups in dopaminergic mesolimbic recruitment by (non-drug) rewards inferred from functional magnetic resonance imaging (fMRI) could partially explain morbidity and mortality from risky-behavior-related causes in adolescents.

Recent findings

Recent findings do not suggest a definitive directionality with regard to whether increased vs decreased mesolimbic responsiveness to nondrug rewards correlates with real-world risk-taking. Inconsistent relationships between reward-activation and real-world risky behavior in these reports reflect in part methodological differences as well as conceptual differences between populations in terms of whether tepid mesolimbic recruitment by rewards is a marker of psychiatric health.

Summary

There are several potential reasons why the directionality of relationships between reward-elicited brain activation and substance use risk (specifically) might differ. These factors include differences between adolescents in histories/exposure of substance use, motivation for substance use, the component of the instrumental behavior being studied, and the cognitive demands of the incentive tasks. Systematic manipulation of these discrepant study factors might offer a way forward to clarify how motivational neurocircuit function relates to addiction risk in adolescents.

Cross-Hemispheric Complementary Prefrontal Mechanisms during Task Switching under Perceptual Uncertainty

Flexible adaptation to changing environments is a representative executive control function implicated in the frontoparietal network that requires appropriate extraction of goal-relevant information through perception of the external environment. It remains unclear, however, how the flexibility is achieved under situations where goal-relevant information is uncertain. To address this issue, the current study examined neural mechanisms for task switching in which task-relevant information involved perceptual uncertainty. Twenty-eight human participants of both sexes alternated behavioral tasks in which they judged motion direction or color of visually presented colored dot stimuli that moved randomly. Task switching was associated with frontoparietal regions in the left hemisphere, and perception of ambiguous stimuli involved contralateral homologous frontoparietal regions. On the other hand, in stimulus-modality-dependent occipitotemporal regions, task coding information was increased during task switching. Effective connectivity analysis revealed that the frontal regions signaled toward the modality-dependent occipitotemporal regions when a relevant stimulus was more ambiguous, whereas the occipitotemporal regions signaled toward the frontal regions when the stimulus was more distinctive. These results suggest that complementary prefrontal mechanisms in the left and right hemispheres help to achieve a behavioral goal when the external environment involves perceptual uncertainty.SIGNIFICANCE STATEMENT In our daily life, environmental information to achieve a goal is not always certain, but we make judgments in such situations, and change our behavior accordingly. This study examined how the flexibility of behavior is achieved in a situation where goal-relevant information involves perceptual uncertainty. fMRI revealed that the lateral prefrontal cortex (PFC) in the left hemisphere is associated with behavioral flexibility, and the perception of ambiguous stimuli involves the PFC in the right hemisphere. These bilateral PFC signaled to stimulus-modality-dependent occipitotemporal regions, depending on perceptual uncertainty and the task to be performed. These top-down signals supplement task coding in the occipitotemporal regions, and highlight interhemispheric prefrontal mechanisms involved in executive control and perceptual decision-making.

Higher Trait Impulsivity and Altered Frontostriatal Connectivity in Betel-Quid Dependent Individuals

Objective: Betel quid dependency (BQD) is characterized by functional and structural brain alterations. Trait impulsivity may influence substance dependence by impacting its neurobiological underpinnings in the frontostriatal circuit. However, little is known about the trait impulsivity and its neural correlates in individuals with BQD.

Methods: Forty-eight participants with BQD and 22 normal controls (NCs) were recruited and scanned on a 3T MRI scanner. Barratt impulsiveness scale (BIS) was used to measure trait impulsivity: motor, attention, and no plan impulsivity. We used voxel-based morphometry (VBM) to assess the relationship between trait impulsivity and gray matter volumes. The relevant clusters identified were served as regions of interest (ROI) seeds. The whole-volume psycho-physiological interactions (PPI) analysis was used to investigate the changes of functional connectivity related to ROI seeds in the cue-reactivity task condition (BQ and control images).

Results: Behaviorally, the BQD group showed significantly higher trait impulsivity including motor and no plan impulsivity than the NCs group. VBM analyses showed that motor impulsivity was negatively associated with gray matter volume of right caudate in the whole sample. No difference in gray matter volume between the two groups was observed. PPI analyses showed that there was a significantly decreased functional connectivity between the right caudate and right dorsolateral prefrontal cortex (DLPFC) when watching BQ related images than control images in individuals with BQD. Furthermore, functional connectivity between the right caudate and right DLPFC was negatively correlated with BQ dependency scores.

Conclusions: Our study demonstrated the structural basis of trait impulsivity in the caudate and provided evidence for abnormal interactions within frontostriatal circuitsin individuals with BQD, which may provide insight into the selection of potential novel therapeutic targets for the treatment of BQ dependency.

Directing Technology Addiction Research in Information Systems

Technology-related addictions have become common in many societies. Consequently, IS research has started examining such issues. In these embryonic stages of research, this line of work has already shown some promise in terms of understanding and tackling technology addiction problems. Nevertheless, there is a need to step back and understand the roots of technology-related addictions and how their foundations evolved in reference disciplines in order to be able to conduct more scientifically informed research on such issues. This study, therefore, explains the concept of behavioral addictions (the family of addictions to which technology-related addictions presumably belong), reviews the field's history and evolution, explains the relevant brain circuitry, and discusses similarities and differences between behavioral and substance addictions. A synthesis of this information provides eight key observations and recommendations that should help the field move forward.

Inhibitory neuromodulation of the putamen to the prefrontal cortex in Internet gaming disorder: How addiction impairs executive control

BACKGROUND AND AIMS

Individuals with addictive disorders are usually characterized by impaired executive control, persistent craving and excessive reward-seeking. However, it is unclear whether there is a deviation in the connection pattern among the neural systems implicated in these problem behaviors.

METHODS

One hundred thirty-six online gaming players were recruited in the current study (68 Internet gaming disorder (IGD) subjects and 68 recreational game users (RGUs) who served as controls matched on age, sex, years of education, and years of gaming). Dynamic interactions among the reward system (striatum), control system (prefrontal cortex), and the interoceptive awareness system (insula) were calculated and compared when subjects were facing gaming cues.

RESULTS

The results revealed that RGUs showed a significant positive correlation in the putamen-middle frontal gyrus (MFG)-insula neural pathway when facing gaming cues, which was missing in the IGD subjects. Additionally, dynamic causal modeling (DCM) analysis revealed that the MFG region was more inhibited by the putamen in the IGD subjects relative to the RGUs.

CONCLUSIONS

These findings suggest that the inhibitory neuromodulation of the putamen to the prefrontal cortex in IGD individuals undermines the balance among the tripartite systems. Our findings provide novel neurobiological evidence for understanding the internal connection bias of the addicted individual's neural system and how the addictive disorder impairs executive control; consequently, the pathway from the striatum to the prefrontal cortex may serve as a potential biomarker to predict the risk of developing an addiction.

Dysfunction of the Prefrontal Cortex in Betel-Quid-Dependent Chewers

Betel quid is the fourth most popular psychoactive agent worldwide. Imaging studies have found altered brain structure in prefrontal cortex (PFC) in betel-quid dependent (BQD) chewers. However, the brain function in PFC associated with BQ use still remains unclear. The present study aimed to examine brain functional activity in PFC in individuals with BQD. This study recruited 48 participants with BQD and 22 normal controls (NCs). Both BQ-specific cue reactivity and Go/NoGo tasks were administered with functional magnetic resonance imaging (fMRI). Behavioral results showed a deficit in the choice reaction time task in BQD group. The fMRI results of the cue reactivity task suggested that, individuals with BQD exhibited responses in right ventromedial PFC, left posterior cingulate cortex (PCC), left lateral parietal lobe (LPL), left middle temporal gyrus and left visual cortex, when seeing BQ images compared with control images. In the Go/NoGo task, relative to NCs group, individuals with BQD showed higher activity in right dorsolateral PFC, right PCC and bilateral LPL between NoGo and Go trials. Across these two tasks, we consistently found disrupted function in PFC in individuals with BQD, which might lead to impaired craving and response inhibition in BQ addiction. Results of current study might shed light on the neural mechanisms involved in BQ use, which could be used as potential guidelines for diagnosis and treatment of BQ dependence.

Electrophysiological Evidence of Event-Related Potential Changes Induced by 12 h Abstinence in Young Smokers Based on the Flanker Study

The cognitive control processes may be disrupted by abstinence in smokers, which may be helpful in the development and maintenance of addictive behavior. The purpose of this study was to measure the performance of cognitive task after 12 h of smoking abstinence by using event-related potentials (ERPs), including the error-related negativity (ERN) and the error positivity (Pe). In Eriksen flanker task, electroencephalography (EEG) signals of 24 smokers were recorded in two conditions: satiety and 12 h abstinence. In the behavioral data, both conditions exhibited more errors and more time on the incongruent trials than congruence. Meantime, the Minnesota Nicotine Withdrawal Scale (MNWS) score was increased during abstinence. Smokers showed reduced ERN and Pe after 12 h of abstinence, compared with satiety condition. The results indicate that the diminished error processing in young smokers after 12 h of abstinence. It may be related to increased withdrawal symptoms. In conclusion, the disrupted neurophysiological indexes in the general behavior monitoring system may be caused by abstinence. The results of this study may provide us with new ideas about the effects of short-term abstinence on brain cognitive neuroscience and be helpful for the solution of relapse.

Functional neural changes and altered cortical-subcortical connectivity associated with recovery from Internet gaming disorder

BACKGROUND AND AIMS

Although studies have suggested that individuals with Internet gaming disorder (IGD) may have impairments in cognitive functioning, the nature of the relationship is unclear given that the information is typically derived from cross-sectional studies.

METHODS

Individuals with active IGD (n = 154) and those individuals no longer meeting criteria (n = 29) after 1 year were examined longitudinally using functional magnetic resonance imaging during performance of cue-craving tasks. Subjective responses and neural correlates were contrasted at study onset and at 1 year.

RESULTS

Subjects' craving responses to gaming cues decreased significantly at 1 year relative to study onset. Decreased brain responses in the anterior cingulate cortex (ACC) and lentiform nucleus were observed at 1 year relative to onset. Significant positive correlations were observed between changes in brain activities in the lentiform nucleus and changes in self-reported cravings. Dynamic causal modeling analysis showed increased ACC-lentiform connectivity at 1 year relative to study onset.

CONCLUSIONS

After recovery from IGD, individuals appear less sensitive to gaming cues. This recovery may involve increased ACC-related control over lentiform-related motivations in the control over cravings. The extent to which cortical control over subcortical motivations may be targeted in treatments for IGD should be examined further.

Structural and Functional Connectivity Between the Amygdala and Orbital Frontal Cortex in Burning Mouth Syndrome: An fMRI Study

Featuring a burning sensation in the tongue or other oral sites in the absence of observable lesions or laboratory findings, burning mouth syndrome (BMS) is a chronic intraoral pain disorder, which is one of the most common medically unexplained oral symptoms/syndromes. Previous studies have suggested that brain changes are involved in BMS; however, the small number of participants in these studies limited the conclusions that could be drawn. The present study aimed to further elucidate the brain anatomical and functional changes in BMS with a relatively large sample. Fifty-three patients (26 BMS patients and 27 gender- and age-matched controls) were recruited. Demographic information was collected via interviews. Visual analogue scale (VAS), anxiety, and depression scale were administered. Participants underwent an MRI scan (including one high-resolution structural scan, one diffusion tensor image, and one session of resting state scan) on the same day. The results showed that BMS patients had higher depression and anxiety levels than controls. BMS patients showed lower gray matter volume (GMV) in the bilateral ventromedial prefrontal cortex (VMPFC) and increased functional connectivity between this region and the bilateral amygdala. Region of interest (ROI) analysis suggested that the functional connectivity between the bilateral VMPFC and amygdala correlated with the years of BMS illness in patients. The brain measures could predict the years of symptoms in the BMS group. These results suggest A potential neuromarker for the diagnosis and treatment of BMS.