Hyperactivation of the cognitive control network in cocaine use disorders during a multisensory Stroop task

Altered integrated and segregated states in cocaine use disorder

Introduction

Cocaine use disorder (CUD) is a chronic brain condition that severely impairs cognitive function and behavioral control. The neural mechanisms underlying CUD, particularly its impact on brain integration-segregation dynamics, remain unclear.

Methods

In this study, we integrate dynamic functional connectivity and graph theory to compare the brain state properties of healthy controls and CUD patients.

Results

We find that CUD influences both integrated and segregated states, leading to distinct alterations in connectivity patterns and network properties. CUD disrupts connectivity involving the default mode network, frontoparietal network, and subcortical structures. In addition, integrated states show distinct sensorimotor connectivity alterations, while segregated states exhibit significant alterations in frontoparietal-subcortical connectivity. Regional connectivity alterations among both states are significantly associated with MOR and H3 receptor distributions, with integrated states showing more receptor-connectivity couplings. Furthermore, CUD alters the positive-negative correlation balance, increases functional complexity at threshold 0, and reduces mean betweenness centrality and modularity in the critical subnetworks. Segregated states in CUD exhibit lower normalized clustering coefficients and functional complexity at a threshold of 0.3. We also identify network properties in integrated states that are reliably correlated with cocaine consumption patterns.

Discussion

Our findings reveal temporal effects of CUD on brain integration and segregation, providing novel insights into the dynamic neural mechanisms underlying cocaine addiction.

The auditory stimulus facilitates memory guidance in distractor suppression in males with substance use disorder

Introduction

Representations in working memory can affect distractor suppression in human visual search, and this process is modulated by a separate top-down cognitive control. An increasing body of research has demonstrated that patients with substance use disorder (SUD) have deficits in cognitive control over filtering interference by perceptual distractors. However, their ability to resist proactive interference from working memory has received comparatively less attention.

Methods

Here, we investigate this issue by employing a working memory/visual search dual-task paradigm. An intervening gap-location search task was instructed to be performed while participants memorized a written color word, with congruent auditory information present during the memory encoding phase on half of the trials.

Results

Results showed that there was a reliable response time (RT) advantage when the meaning of the memory sample agreed with the color of one of the distractors under the visual alone condition. However, such a result was only found in the control group. More importantly, both groups exhibited comparable facilitation under the audiovisual condition, with the facilitation effect appearing later in the SUD group. Furthermore, the facilitation effect was superior in magnitude and time course under the audiovisual condition to the visual alone condition.

Discussion

These findings highlight how patients with SUD resist distractor interference at the memory level and extend our understanding of how working memory, selective attention, and audiovisual enhancement interact to optimize perceptual decisions in patients with SUD.

The Effects of Digital Addiction on Brain Function and Structure of Children and Adolescents: A Scoping Review

The escalating prevalence of studies investigating digital addiction (DA) and its detrimental impact on the human brain's structure and functionality has been noticeable in recent years. Yet, an overwhelming majority of these reviews have been predominantly geared towards samples comprising college students or adults and have only inspected a single variant of DA, such as internet gaming disorder, internet addiction disorder, problematic smartphone use, tablet overuse, and so forth. Reviews focusing on young children and adolescents (ages 0-18), or those which amalgamate various types of DA, are decidedly scarce. Given this context, summarizing the effects of DA on brain structure and functionality during the vital developmental stage (0-18 years) is of immense significance. A scoping review, complying with the PRISMA extension for such reviews, was conducted to amalgamate findings from 28 studies spanning a decade (2013-2023) and to examine the influence of assorted forms of DA on the brains of children and adolescents (0-18 years). The synthesized evidence indicated two primary results: (1) DA exerts harmful effects on the structure and functionality of the brains of children and adolescents, and (2) the prefrontal lobe is the region most consistently reported as impacted across all research. Furthermore, this review discerned a notable void of studies investigating the neural indices of digital addiction, along with a shortage of studies focusing on young children (0-6 years old) and longitudinal evidence. This research could provide the necessary theoretical basis for the thwarting and intervention of digital addiction, a measure indispensable for ensuring healthy brain development in children and adolescents.

Stroop-related cerebellar and temporal activation is correlated with negative affect and alcohol use disorder severity

Impairment in cognitive control in alcohol use disorder (AUD) contributes to difficulty controlling alcohol use and, in many populations, difficulties with emotion regulation. However, the most reliable and robust marker of clinically-relevant deficits in cognitive control in AUD is unclear. Our aims were to measure relationships between BOLD signal during a Stroop task and AUD severity and change in BOLD signal and change in drinking over three weeks. We also aimed to explore the relationships between BOLD signal and subjective negative affect. Thirty-three individuals with AUD underwent a multisensory Stroop task during functional magnetic resonance imaging (fMRI), as well as a battery of neuropsychological tests and self-report assessments of negative affect and AUD severity. Greater activation in temporal gyrus and cerebellum during incongruent trials compared to congruent trials was observed, and percent signal change (incongruent minus congruent) in both clusters was positively correlated with AUD severity and self-reported negative affect. Neuropsychological task performance and self-reported impulsivity were not highly correlated with AUD severity. Hierarchical regression analyses indicated that percent signal change (incongruent minus congruent) in cerebellum was independently associated with negative affect after controlling for recent and chronic drinking. In a subset of individuals (n = 23) reduction in cerebellar percent signal change (incongruent minus congruent) was correlated with increases in percent days abstinent over 3 weeks. BOLD activation during this Stroop task may therefore be an important objective marker of AUD severity and negative affect. The potential importance of the cerebellum in emotion regulation and AUD severity is highlighted.

Effects of attentional bias modification therapy on the cue reactivity and cognitive control networks in participants with cocaine use disorders

BACKGROUND

While attentional bias modification therapy (ABMT) alters drug-related behaviors in some substance users, results have been mixed in individuals with cocaine use disorders (CUD).

OBJECTIVES

The current study examined whether ABMT affected brain functioning during independent measures of cue reactivity (i.e., cocaine versus food cues) and cognitive control (i.e., incongruent versus congruent trials), and whether brain activity was associated with baseline or post-intervention cocaine use.

METHODS

37 participants (62% male) were randomly assigned to ABMT or control therapy. Clinical and neuroimaging assessments occurred at baseline and immediately post-intervention, with additional clinical testing at 2 weeks and 3 months following intervention. Cocaine use was assessed through self-report.

RESULTS

Slower reaction times and increased functional activation (prefrontal cortex, posterior parietal cortex) were observed for incongruent versus congruent stimuli and increased functional activation for cocaine relative to food videos (ventral striatum, dorsolateral prefrontal cortex and orbitofrontal cortex). The default-mode network (DMN) was not deactivated during exposure to cocaine videos. The degree of activation during cocaine relative to food cues was associated with baseline cocaine use (insula only) and reduction in use following treatment (insula and anterior DMN) above and beyond clinical variables. Cognitive control network activity was not associated with cocaine use at baseline or following treatment. ABMT therapy did not differentially affect cocaine use or functional activation during either task.

CONCLUSION

Current results suggest a relationship between cue reactivity network activation and cocaine use, but question the efficacy of ABMT in changing brain function during cue reactivity or cognitive control tasks.

Synergistic effects of marijuana abuse and HIV infection on neural activation during a cognitive interference task

Marijuana use, which is disproportionately prevalent among human immunodeficiency virus (HIV)-infected persons, can alter activity in fronto-parietal regions during cognitively demanding tasks. While HIV is also associated with altered neural activation, it is not known how marijuana may further affect brain function in this population. Our study examined the independent and additive effects of HIV infection and regular marijuana use on neural activation during a cognitive interference task. The sample included 93 adults who differed on marijuana (MJ) and HIV statuses (20 MJ+/HIV+, 19 MJ+/HIV-, 29 MJ-/HIV+, 25 MJ-/HIV-). Participants completed a counting Stroop task during a functional magnetic resonance imaging scan. Main and interactive effects on neural activation during interference versus neutral blocks were examined using a mixed-effects analysis. The sample showed the expected Stroop effect for both speed and accuracy. There were main effects of MJ in the right and left inferior parietal lobules, with the left cluster extending into the posterior middle temporal gyrus and a main effect of HIV in the dorsal anterior cingulate cortex. There was an interaction in the left fronto-insular cortex, such that the MJ+/HIV+ group had the largest increase in activation compared with other groups. Among MJ+, signal change in this cluster correlated positively with cumulative years of regular marijuana use. These results suggest that comorbid HIV and marijuana use is associated with complex neural alterations in multiple brain regions during cognitive interference. Follow-up research is needed to determine how marijuana-related characteristics may moderate HIV neurologic disease and impact real-world functioning.

fMRI Stroop and behavioral treatment for cocaine-dependence: Preliminary findings in methadone-maintained individuals

BACKGROUND

Although behavioral treatment for cocaine use disorders is common, the use of cognitive neuroscience methods to investigate these treatments' mechanisms of action remains limited. Cognitive control (e.g., as measured by the Stroop task) has been proposed to be central to cocaine-use disorders, including treatment response.

METHODS

Participants were methadone-maintained, cocaine-dependent individuals who were participating in a randomized clinical trial (RCT) of 8 weeks of treatment for cocaine-use disorder and randomized to outpatient treatment as usual (TAU) or computer-based cognitive-behavioral therapy (CBT4CBT) plus TAU. Participants completed fMRI Color-Word Stroop task at beginning-of-treatment (N = 19) and post-treatment (N = 10). Analyses assessed correlations between beginning-of-treatment Stroop effect with methadone dose or within-treatment cocaine abstinence, change in Stroop-effect at post- versus beginning-of-treatment, and correlations between 'change in Stroop effect' with methadone dose or within-treatment cocaine abstinence.

RESULTS

Higher methadone dose was associated with higher beginning-of-treatment Stroop-related activity in the declive, culmen, and lingual gyrus. Stroop-related activity was reduced at post-treatment relative to beginning-of-treatment in the medial frontal gyrus/cingulate gyrus and thalamus/midbrain/culmen. Greater reduction in Stroop-related activity was associated with better within-treatment abstinence.

CONCLUSIONS

Diminished Stroop-related activity following treatment may be consistent with improved efficiency of cognitive-control-related activity. Although preliminary, this study is the first to demonstrate a relationship between better treatment outcomes (lower cocaine use during treatment) and greater reduction in Stroop-related activity at post- versus beginning-of-treatment in cocaine users. These findings extend prior work.

The long-term effects of cocaine use on cognitive functioning: A systematic critical review

BACKGROUND

The predominant view of chronic cocaine use maintains that it causes a broad range of cognitive deficits. However, concerns about the possibly deleterious impact of cocaine on cognitive functioning have yet to be thoroughly vetted. This review addresses the impact of cocaine use on such cognitive domains as executive function, memory, language, and psychomotor speed. Additionally, relevant neuroimaging data is considered to understand the neural basis underlying cocaine-related effects on cognitive functioning.

METHODS

We searched PubMed, Google Scholar, and Embase using the search terms "cocaine and cognition," "cocaine and cognitive functioning," and "cocaine and cognitive deficits or impairment." To meet inclusion criteria we evaluated only cognitive and neuroimaging studies describing the long-term effects of cocaine on cognitive functioning published from 1999 to 2016.

RESULTS

The majority of studies reported statistically significant differences between cocaine users and non-drug-using controls in brain structures, blood-oxygen-level dependent signals, and brain metabolism. However, differences in cognitive performance were observed on a minority of measures. Additionally, the majority of studies were not compared against normative data.

CONCLUSIONS

The current evidence does not support the view that chronic cocaine use is associated with broad cognitive deficits. The view that cocaine users have broad cognitive deficits is inaccurate based upon current evidence, and the perpetuation of this view may have negative implications for treatment programs and development of public policies.

Adolescent brain cognitive development (ABCD) study: Overview of substance use assessment methods

One of the objectives of the Adolescent Brain Cognitive Development (ABCD) Study (https://abcdstudy.org/) is to establish a national longitudinal cohort of 9 and 10 year olds that will be followed for 10 years in order to prospectively study the risk and protective factors influencing substance use and its consequences, examine the impact of substance use on neurocognitive, health and psychosocial outcomes, and to understand the relationship between substance use and psychopathology. This article provides an overview of the ABCD Study Substance Use Workgroup, provides the goals for the workgroup, rationale for the substance use battery, and includes details on the substance use module methods and measurement tools used during baseline, 6-month and 1-year follow-up assessment time-points. Prospective, longitudinal assessment of these substance use domains over a period of ten years in a nationwide sample of youth presents an unprecedented opportunity to further understand the timing and interactive relationships between substance use and neurocognitive, health, and psychopathology outcomes in youth living in the United States.

Alterations in functional brain networks associated with loss-chasing in gambling disorder and cocaine-use disorder

BACKGROUND

Continued, persistent gambling to recover accumulating losses, or 'loss-chasing', is a behavioral pattern linked particularly closely to gambling disorder (GD) but may reflect impaired decision-making processes relevant to drug addictions like cocaine-use disorder (CUD). However, little is known regarding the neurocognitive mechanisms of this complex, maladaptive behavior, particularly in individuals with addictive disorders.

METHODS

Seventy participants (25 GD, 18 CUD, and 27 healthy comparison (HC)) completed a loss-chase task during fMRI. Engagement of functional brain networks in response to losing outcomes and during decision-making periods preceding choices to loss-chase or to quit chasing losses were investigated using independent component analysis (ICA). An exploratory factor analysis was performed to examine patterns of coordinated engagement across identified networks.

RESULTS

In GD relative to HC and CUD participants, choices to quit chasing were associated with greater engagement of a medial frontal executive-processing network. By comparison, CUD participants exhibited altered engagement of a striato-amygdala motivational network in response to losing outcomes as compared to HC, and during decision-making as compared to GD. Several other networks were differentially engaged during loss-chase relative to quit-chasing choices, but did not differ across participant groups. Exploratory factor analysis identified a system of coordinated activity across prefrontal executive-control networks that was greater in GD and CUD relative to HC participants and was associated with increased chasing persistence across all participants.

CONCLUSIONS

Results provide evidence of shared and distinct neurobiological mechanisms in substance and behavioral addictions, and lend insight into potential cognitive interventions targeting loss-chasing behavior in GD.

Functional neural changes following behavioral therapies and disulfiram for cocaine dependence

A growing literature exists on neural correlates of treatment outcome. However, different types-or components of-treatment have distinct theorized mechanisms of action. And it is not yet known how changes in neural activity across treatment relate to engagement in different treatment components. Participants with cocaine use disorders in a randomized clinical trial received cognitive-behavioral therapy (CBT) plus, in a 2 × 2 design, contingency management (CM) or no CM, and disulfiram or placebo. Participants performed a functional MRI Stroop task, a measure of cognitive control, at the beginning of and after the 12-week treatment. Analyses assessed changes in Stroop-related neural activity within the sample overall and assessed how changes in Stroop-related activity correlated with measures of treatment process specific to each form of treatment (i.e., participation in CBT sessions, receipt of CM prizes, administration of disulfiram pills). Within the sample overall, compared with beginning of treatment, posttreatment Stroop-related neural activity was diminished in the hippocampus, thalamus, cingulate, precentral, post- and precentral gyrus, and precuneus and culmen regions (pFWE < .05). In separate whole-brain correlation analyses, greater reductions in Stroop-related activity were associated with more treatment engagement-"CBT sessions" with the precentral gyrus, inferior parietal lobule, and middle and medial frontal gyrus; "CM prizes" with the postcentral frontal gyrus. Disulfiram "medication days" were not associated with changes in Stroop-related activity. Findings suggest that key process indicators of CBT and CM may be associated with functional changes in cognitive-control-related neurocircuitry. (PsycINFO Database Record

Disrupted Control Network Connectivity in Abstinent Patients with Alcohol Dependence

OBJECTIVE

Alcohol causes damage to the brain and is associated with various functional impairments. However, much of the brain damage can be reversed by abstaining for enough time. This study aims to investigate the patterns and degrees of brain function in abstinent patients with alcohol dependence by using resting-state functional connectivity.

METHODS

26 male patients with alcohol dependence (alcohol group) and 28 age-matched male healthy volunteers (control group) were recruited from a mental hospital and the community, respectively. Using 3T MRI scan data, the resting-state functional connectivity of the task-negative and task-positive networks was determined and compared between the groups.

RESULTS

There were no significant group differences in the resting-state functional connectivity in the default mode or in the salience and sensorimotor networks. Compared with the control group, the alcohol group showed significantly lower functional connectivity in the executive control network, especially in the cingulo-opercular network and, in some regions of interest, the dorsal attention network.

CONCLUSION

This finding suggests that some brain networks do not normalize their functions after abstinence from drinking, and these results may be helpful in future research to investigate the mechanisms for craving alcohol and alcohol relapse prevention.

Top-Down Network Effective Connectivity in Abstinent Substance Dependent Individuals

Objective

We hypothesized that compared to healthy controls, long-term abstinent substance dependent individuals (SDI) will differ in their effective connectivity between large-scale brain networks and demonstrate increased directional information from executive control to interoception-, reward-, and habit-related networks. In addition, using graph theory to compare network efficiencies we predicted decreased small-worldness in SDI compared to controls.

Methods

50 SDI and 50 controls of similar sex and age completed psychological surveys and resting state fMRI. fMRI results were analyzed using group independent component analysis; 14 networks-of-interest (NOI) were selected using template matching to a canonical set of resting state networks. The number, direction, and strength of connections between NOI were analyzed with Granger Causality. Within-group thresholds were p<0.005 using a bootstrap permutation. Between group thresholds were p<0.05, FDR-corrected for multiple comparisons. NOI were correlated with behavioral measures, and group-level graph theory measures were compared.

Results

Compared to controls, SDI showed significantly greater Granger causal connectivity from right executive control network (RECN) to dorsal default mode network (dDMN) and from dDMN to basal ganglia network (BGN). RECN was negatively correlated with impulsivity, behavioral approach, and negative affect; dDMN was positively correlated with impulsivity. Among the 14 NOI, SDI showed greater bidirectional connectivity; controls showed more unidirectional connectivity. SDI demonstrated greater global efficiency and lower local efficiency.

Conclusions

Increased effective connectivity in long-term abstinent drug users may reflect improved cognitive control over habit and reward processes. Higher global and lower local efficiency across all networks in SDI compared to controls may reflect connectivity changes associated with drug dependence or remission and requires future, longitudinal studies to confirm.

Neural Circuitry of Impaired Emotion Regulation in Substance Use Disorders

Impaired emotion regulation contributes to the development and severity of substance use disorders (substance disorders). This review summarizes the literature on alterations in emotion regulation neural circuitry in substance disorders, particularly in relation to disorders of negative affect (without substance disorder), and it presents promising areas of future research. Emotion regulation paradigms during functional magnetic resonance imaging are conceptualized into four dimensions: affect intensity and reactivity, affective modulation, cognitive modulation, and behavioral control. The neural circuitry associated with impaired emotion regulation is compared in individuals with and without substance disorders, with a focus on amygdala, insula, and prefrontal cortex activation and their functional and structural connectivity. Hypoactivation of the rostral anterior cingulate cortex/ventromedial prefrontal cortex (rACC/vmPFC) is the most consistent finding across studies, dimensions, and clinical populations (individuals with and without substance disorders). The same pattern is evident for regions in the cognitive control network (anterior cingulate and dorsal and ventrolateral prefrontal cortices) during cognitive modulation and behavioral control. These congruent findings are possibly related to attenuated functional and/or structural connectivity between the amygdala and insula and between the rACC/vmPFC and cognitive control network. Although increased amygdala and insula activation is associated with impaired emotion regulation in individuals without substance disorders, it is not consistently observed in substance disorders. Emotion regulation disturbances in substance disorders may therefore stem from impairments in prefrontal functioning, rather than excessive reactivity to emotional stimuli. Treatments for emotion regulation in individuals without substance disorders that normalize prefrontal functioning may offer greater efficacy for substance disorders than treatments that dampen reactivity.

An fMRI study of multimodal selective attention in schizophrenia

BACKGROUND

Studies have produced conflicting evidence regarding whether cognitive control deficits in patients with schizophrenia result from dysfunction within the cognitive control network (CCN; top-down) and/or unisensory cortex (bottom-up).

AIMS

To investigate CCN and sensory cortex involvement during multisensory cognitive control in patients with schizophrenia.

METHOD

Patients with schizophrenia and healthy controls underwent functional magnetic resonance imaging while performing a multisensory Stroop task involving auditory and visual distracters.

RESULTS

Patients with schizophrenia exhibited an overall pattern of response slowing, and these behavioural deficits were associated with a pattern of patient hyperactivation within auditory, sensorimotor and posterior parietal cortex. In contrast, there were no group differences in functional activation within prefrontal nodes of the CCN, with small effect sizes observed (incongruent-congruent trials). Patients with schizophrenia also failed to upregulate auditory cortex with concomitant increased attentional demands.

CONCLUSIONS

Results suggest a prominent role for dysfunction within auditory, sensorimotor and parietal areas relative to prefrontal CCN nodes during multisensory cognitive control.

Dorsal medial prefrontal cortex (MPFC) circuitry in rodent models of cocaine use: implications for drug addiction therapies

Although the importance of the medial prefrontal cortex (MPFC) in cocaine addiction is well established, its precise contribution to cocaine seeking, taking and relapse remains incompletely understood. In particular, across two different models of cocaine self-administration, pharmacological or optogenetic activation of the dorsal MPFC has been reported to sometimes promote and sometimes inhibit cocaine seeking. We highlight important methodological differences between the two experimental paradigms and propose a framework to potentially reconcile the apparent discrepancy. We also draw parallels between these pre-clinical models of cocaine self-administration and human neuro-imaging studies in cocaine users, and argue that both lines of evidence point to dynamic interactions between cue-reactivity processes and control processes within the dorsal MPFC circuitry. From a translational perspective, these findings underscore the importance of interventions and therapeutics targeting not just a brain region, but a specific computational process within that brain region, and may have implications for the design and implementation of more effective treatments for human cocaine addiction.

Cognitive control network function in alcohol use disorder before and during treatment with lorazepam

Individuals with alcohol use disorders (AUDs) have deficits in cognitive control, but how they change with treatment is unclear. Seven patients with AUD and anxiety from an open-label trial of disulfiram plus lorazepam performed a multisensory Stroop task during fMRI (both pre and post initiation of treatment), and were compared to nine healthy controls (HCs) (n = 16; Albuquerque, NM; years 2009-2012). Evoked BOLD signal and resting state functional connectivity were compared (HC vs. AUD; Scan 1 vs. Scan 2). AUD demonstrated hyperactivity and altered connectivity in the cognitive control network compared to HC, but treatment did not normalize function.

Common and distinct neural correlates of inhibitory dysregulation: stroop fMRI study of cocaine addiction and intermittent explosive disorder

Despite the high prevalence and consequences associated with externalizing psychopathologies, little is known about their underlying neurobiological mechanisms. Studying multiple externalizing disorders, each characterized by compromised inhibition, could reveal both common and distinct mechanisms of impairment. The present study therefore compared individuals with intermittent explosive disorder (IED) (N = 11), individuals with cocaine use disorder (CUD) (N = 21), and healthy controls (N = 17) on task performance and functional magnetic resonance imaging (fMRI) activity during an event-related color-word Stroop task; self-reported trait anger expression was also collected in all participants. Results revealed higher error-related activity in the two externalizing psychopathologies as compared with controls in two subregions of the dorsolateral prefrontal cortex (DLPFC) (a region known to be involved in exerting cognitive control during this task), suggesting a neural signature of inhibitory-related error processing common to these psychopathologies. Interestingly, in one DLPFC subregion, error-related activity was especially high in IED, possibly indicating a specific neural correlate of clinically high anger expression. Supporting this interpretation, error-related DLPFC activity in this same subregion positively correlated with trait anger expression across all participants. These collective results help to illuminate common and distinct neural signatures of impaired self-control, and could suggest novel therapeutic targets for increasing self-control in clinical aggression specifically and/or in various externalizing psychopathologies more generally.

Cognitive control in alcohol use disorder: deficits and clinical relevance

Cognitive control refers to the internal representation, maintenance, and updating of context information in the service of exerting control over thoughts and behavior. Deficits in cognitive control likely contribute to difficulty in maintaining abstinence in individuals with alcohol use disorders (AUD). In this article, we define three cognitive control processes in detail (response inhibition, distractor interference control, and working memory), review the tasks measuring performance in these areas, and summarize the brain networks involved in carrying out these processes. Next, we review evidence of deficits in these processes in AUD, including both metrics of task performance and functional neuroimaging. Finally, we explore the clinical relevance of these deficits by identifying predictors of clinical outcome and markers that appear to change (improve) with treatment. We observe that individuals with AUD experience deficits in some, but not all, metrics of cognitive control. Deficits in cognitive control may predict clinical outcome in AUD, but more work is necessary to replicate findings. It is likely that performance on tasks requiring cognitive control improves with abstinence, and with some psychosocial and medication treatments. Future work should clarify which aspects of cognitive control are most important to target during treatment of AUD.

Neural responses to various rewards and feedback in the brains of adolescent Internet addicts detected by functional magnetic resonance imaging

AIM

This study aimed to examine differences in brain activation for various types of reward and feedback in adolescent Internet addicts (AIA) and normal adolescents (NA) using functional magnetic resonance imaging (fMRI).

METHODS

AIA (n = 15) and NA (n = 15) underwent fMRI while performing easy tasks for which performance feedback (PF), social reward (SR) (such as compliments), or monetary reward (MR) was given. Using the no reward (NR) condition, three types of contrasts (PF-NR, SR-NR, and MR-NR) were analyzed.

RESULTS

In NA, we observed activation in the reward-related subcortical system, self-related brain region, and other brain areas for the three contrasts, but these brain areas showed almost no activation in AIA. Instead, AIA showed significant activation in the dorsolateral prefrontal cortex for the PF-NR contrast and the negative correlation was found between the level of activation in the left superior temporal gyrus (BA 22) and the duration of Internet game use per day in AIA.

CONCLUSION

These findings suggest that AIA show reduced levels of self-related brain activation and decreased reward sensitivity irrespective of the type of reward and feedback. AIA may be only sensitive to error monitoring regardless of positive feelings, such as sense of satisfaction or achievement.