Salience network coupling is linked to both tobacco smoking and symptoms of attention deficit hyperactivity disorder (ADHD)

Data-driven connectivity profiles relate to smoking cessation outcomes

At a group level, nicotine dependence is linked to differences in resting-state functional connectivity (rs-FC) within and between three large-scale brain networks: the salience network (SN), default mode network (DMN), and frontoparietal network (FPN). Yet, individuals may display distinct patterns of rs-FC that impact treatment outcomes. This study used a data-driven approach, Group Iterative Multiple Model Estimation (GIMME), to characterize shared and person-specific rs-FC features linked with clinically-relevant treatment outcomes. 49 nicotine-dependent adults completed a resting-state fMRI scan prior to a two-week smoking cessation attempt. We used GIMME to identify group, subgroup, and individual-level networks of SN, DMN, and FPN connectivity. Regression models assessed whether within- and between-network connectivity of individual rs-FC models was associated with baseline cue-induced craving, and craving and use of regular cigarettes (i.e., "slips") during cessation. As a group, participants displayed shared patterns of connectivity within all three networks, and connectivity between the SN-FPN and DMN-SN. However, there was substantial heterogeneity across individuals. Individuals with greater within-network SN connectivity experienced more slips during treatment, while individuals with greater DMN-FPN connectivity experienced fewer slips. Individuals with more anticorrelated DMN-SN connectivity reported lower craving during treatment, while SN-FPN connectivity was linked to higher craving. In conclusion, in nicotine-dependent adults, GIMME identified substantial heterogeneity within and between the large-scale brain networks. Individuals with greater SN connectivity may be at increased risk for relapse during treatment, while a greater positive DMN-FPN and negative DMN-SN connectivity may be protective for individuals during smoking cessation treatment.

Cue-reactivity targeted smoking cessation intervention in individuals with tobacco use disorder: a scoping review

Objectives

Cue-reactivity is a critical step leading to the emergence of addictive psychology and the triggering of addictive behaviors within the framework of addiction theory and is considered a significant risk factor for addiction-related behaviors. However, the effect of cue-reactivity targeted smoking cessation intervention and the cue-reactivity paradigms used in the randomized controlled trials varies, which introduces more heterogeneity and makes a side-by-side comparison of cessation responses difficult. Therefore, the scoping review aims to integrate existing research and identify evidence gaps.

Methods

We searched databases in English (PubMed and Embase) and Chinese (CNKI and Wanfang) using terms synonymous with 'cue' and 'tobacco use disorder (TUD)' to April 2023, and via hand-searching and reference screening of included studies. Studies were included if they were randomized controlled trials taking cue-reactivity as an indicator for tobacco use disorder (TUD) defined by different kinds of criteria.

Results

Data were extracted on each study's country, population, methods, timeframes, outcomes, cue-reactivity paradigms, and so on. Of the 2,944 literature were retrieved, 201 studies met the criteria and were selected for full-text screening. Finally, 67 pieces of literature were selected for inclusion and data extraction. The results mainly revealed that non-invasive brain stimulation and exercise therapy showed a trend of greater possibility in reducing subjective craving compared to the remaining therapies, despite variations in the number of research studies conducted in each category. And cue-reactivity paradigms vary in materials and mainly fall into two main categories: behaviorally induced craving paradigm or visually induced craving paradigm.

Conclusion

The current studies are still inadequate in terms of comparability due to their heterogeneity, cue-reactivity can be conducted in the future by constructing a standard library of smoking cue materials. Causal analysis is suggested in order to adequately screen for causes of addiction persistence, and further explore the specific objective cue-reactivity-related indicators of TUD.

Structural differences among children, adolescents, and adults with attention-deficit/hyperactivity disorder and abnormal Granger causality of the right pallidum and whole-brain

Attention-deficit/hyperactivity disorder (ADHD) is a childhood mental health disorder that often persists to adulthood and is characterized by inattentive, hyperactive, or impulsive behaviors. This study investigated structural and effective connectivity differences through voxel-based morphometry (VBM) and Granger causality analysis (GCA) across child, adolescent, and adult ADHD patients. Structural and functional MRI data consisting of 35 children (8.64 ± 0.81 years), 40 adolescents (14.11 ± 1.83 years), and 39 adults (31.59 ± 10.13 years) was obtained from New York University Child Study Center for the ADHD-200 and UCLA dataset. Structural differences in the bilateral pallidum, bilateral thalamus, bilateral insula, superior temporal cortex, and the right cerebellum were observed among the three ADHD groups. The right pallidum was positively correlated with disease severity. The right pallidum as a seed precedes and granger causes the right middle occipital cortex, bilateral fusiform, left postcentral gyrus, left paracentral lobule, left amygdala, and right cerebellum. Also, the anterior cingulate cortex, prefrontal cortex, left cerebellum, left putamen, left caudate, bilateral superior temporal pole, middle cingulate cortex, right precentral gyrus, and the left supplementary motor area demonstrated causal effects on the seed region. In general, this study showed the structural differences and the effective connectivity of the right pallidum amongst the three ADHD age groups. Our work also highlights the evidence of the frontal-striatal-cerebellar circuits in ADHD and provides new insights into the effective connectivity of the right pallidum and the pathophysiology of ADHD. Our results further demonstrated that GCA could effectively explore the interregional causal relationship between abnormal regions in ADHD.

The clinical, neuropsychological, and brain functional characteristics of the ADHD restrictive inattentive presentation

Objectives

There is an ongoing debate about the restrictive inattentive (RI) presentation of attention deficit hyperactivity disorder (ADHD). The current study aimed to systematically investigate the clinical, neuropsychological, and brain functional characteristics of children with ADHD restrictive inattentive presentation.

Methods

A clinical sample of 789 children with or without ADHD participated in the current study and finished clinical interviews, questionnaires, and neuropsychological tests. Those individuals with a diagnosis of ADHD were further divided into three subgroups according to the presentation of inattentive and/or hyperactive/impulsive symptoms, the ADHD-RI, the ADHD-I (inattentive), and the ADHD-C (combined) groups. Between-group comparisons were carried out on each clinical and neuropsychological measure using ANCOVA, with age and sex as covariates. Bonferroni corrections were applied to correct for multiple comparisons. Two hundred twenty-seven of the subjects also went through resting-state functional magnetic resonance imaging scans. Five ADHD-related brain functional networks, including the default mode network (DMN), the dorsal attention network (DAN), the ventral attention network, the executive control network, and the salience network, were built using predefined regions of interest (ROIs). Voxel-based group-wise comparisons were performed.

Results

Compared with healthy controls, all ADHD groups presented more clinical problems and weaker cognitive function. Among the ADHD groups, the ADHD-C group had the most clinical problems, especially delinquent and aggressive behaviors. Regarding cognitive function, the ADHD-RI group displayed the most impaired sustained attention, and the ADHD-C group had the worst response inhibition function. In terms of brain functional connectivity (FC), reduced FC in the DMN was identified in the ADHD-C and the ADHD-I groups but not the ADHD-RI group, compared to the healthy controls. Subjects with ADHD-I also presented decreased FC in the DAN in contrast to the control group. The ADHD-RI displayed marginally significantly lower FC in the salience network compared to the ADHD-I and the control groups.

Conclusion

The ADHD-RI group is distinguishable from the ADHD-I and the ADHD-C groups. It is characterized by fewer externalizing behaviors, worse sustained attention, and better response inhibition function. The absence of abnormally high hyperactive/impulsive symptoms in ADHD-RI might be related to less impaired brain function in DMN, but potentially more impairment in the salience network.

Trait dialectical thinking is associated with the strength of functional coupling between the dACC and the default mode network

Dialectical thinking is an overarching and sophisticated thinking style that involves accepting and resolving contradictions. The current study examined whether the dispositional tendency of dialectical thinking is mediated by organizational patterns of intrinsic brain networks. Based on previous theoretical and empirical works, we hypothesized that the dorsal anterior cingulate cortex (dACC), the hub for conflict processing, shows increased couplings with nodes in the default mode network (DMN). A sample of 380 young and healthy participants completed a self-reported measure of dialectical thinking and underwent resting-state functional magnetic resonance imaging scanning. Results of seed-based correlational ROI and whole-brain analyses supported our hypothesis that trait dialectical thinking was positively correlated with the strength of the dACC-DMN couplings. These findings demonstrate the possibility of identifying network-level neural representations of sociocultural orientations.

Functional connectivity of the anterior insula during withdrawal from cigarette smoking

Currently available therapies for smoking cessation have limited efficacy, and potential treatments that target specific brain regions are under evaluation, with a focus on the insula. The ventral and dorsal anterior subregions of the insula serve distinct functional networks, yet our understanding of how these subregions contribute to smoking behavior is unclear. Resting-state functional connectivity (RSFC) provides a window into network-level function associated with smoking-related internal states. The goal of this study was to determine potentially distinct relationships of ventral and dorsal anterior insula RSFC with cigarette withdrawal after brief abstinence from smoking. Forty-seven participants (24 women; 18-45 years old), who smoked cigarettes daily and were abstinent from smoking overnight (~12 h), provided self-reports of withdrawal and underwent resting-state fMRI before and after smoking the first cigarette of the day. Correlations between withdrawal and RSFC were computed separately for ventral and dorsal anterior insula seed regions in whole-brain voxel-wise analyses. Withdrawal was positively correlated with RSFC of the right ventral anterior insula and dorsal anterior cingulate cortex (dACC) before but not after smoking. The correlation was mainly due to a composite effect of craving and physical symptoms of withdrawal. These results suggest a role of right ventral anterior insula-dACC connectivity in the internal states that maintain smoking behavior (e.g., withdrawal) and present a specific neural target for brain-based therapies seeking to attenuate withdrawal symptoms in the critical early stages of smoking cessation.

Transdiagnostic neuroimaging of reward system phenotypes in ADHD and comorbid disorders

ADHD is a disorder characterized by changes in the reward system and which is highly comorbid with other mental disorders, suggesting common neurobiological pathways. Transdiagnostic neuroimaging findings could help to understand whether a dysregulated reward pathway might be the actual link between ADHD and its comorbidities. We here synthesize ADHD neuroimaging findings on the reward system with findings in obesity, depression, and substance use disorder including their comorbid appearance regarding neuroanatomical features (structural MRI) and activation patterns (resting-state and functional MRI). We focus on findings from monetary-incentive-delay (MID) and delay-discounting (DD) tasks and then review data on striatal connectivity and volumetry. Next, for better understanding of comorbidity in adult ADHD, we discuss these neuroimaging features in ADHD, obesity, depression and substance use disorder and ask whether ADHD heterogeneity and comorbidity are reflected by a common dysregulation in the reward system. Finally, we highlight conceptual issues related to heterogeneous paradigms, different phenotyping, longitudinal prediction and highlight some promising future directions for using striatal reward functioning as a clinical biomarker.

The relationship between ambivalence, alexithymia, and salience network dysfunction in schizophrenia

Ambivalence in schizophrenia is worth investigating its association with salience processing and alexithymia using functional MRI. Twenty-two patients with schizophrenia and 22 healthy controls were scanned during the ambivalence task of matching picture (ambivalent, positive and negative) and word (positive and negative) stimuli, and the Toronto Alexithymia Scale (TAS) was rated. Patients exhibited decreased activity in the anterior cingulate cortex (ACC) and insula compared to controls, and ACC activity in the ambivalent condition was negatively correlated with the TAS score in patients. Ambivalence in schizophrenia may be based on salience network dysfunction, and this disturbance may be related to alexithymia.

The changes of brain functional networks in young adult smokers based on independent component analysis

Intrinsic functional connectivity (FC) networks, including the default mode network (DMN), central executive network (CEN), and salience network (SN), have been implicated in nicotine addiction. However, litter evidence exists about the abnormalities in the three networks in young adult smokers. Forty-eight young adult smokers and 49 age- and gender-matched non-smokers were recruited in the present study. Resting-state functional magnetic resonance imaging (fMRI) data were analyzed by a combination of independent component analysis (ICA) and dual regression to identify potential differences of FC patterns in the DMN, CEN, and SN. Compared to non-smokers, young adult smokers showed enhanced FC of the left posterior cingulate cortex (LPCC), right medial prefrontal cortex (RMPFC) and right precuneus within the DMN network, of the right dorsolateral prefrontal cortex (DLPFC) within the right CEN, and of the left anterior insula (LAI) within the SN. We also found increased FC between the DMN, CEN and key node of the SN (anterior insula, AI). Correlation analysis showed that the increased FC within the networks was significantly correlated with smoking behaviors (pack-years, smoking duration, FTND, first smoking age, and number of cigarettes per day). Our findings may provide additional evidence for conceptualizing the framework of nicotine addiction as a disease of intercommunicating brain networks.

Diagnosis and treatment of patients with comorbid substance use disorder and adult attention-deficit and hyperactivity disorder: a review of recent publications

PURPOSE OF REVIEW

Attention-deficit and hyperactivity disorder (ADHD) often presents with comorbid substance use disorders (SUD). Due to similarities in key symptoms of both disorders and suboptimal efficacy of the available treatments, clinicians are faced with difficulties in the diagnosis and treatment of these patients with both disorders. This review addresses recent publications between 2017 and 2019 on the etiology, prevalence, diagnosis and treatment of co-occurring ADHD and SUD.

RECENT FINDINGS

ADHD is diagnosed in 15-20% of SUD patients, mostly as ADHD with combined (hyperactive/inattentive) presentation. Even during active substance use, screening with the Adult ADHD Self-Report Scale (ASRS) is useful to address whether further diagnostic evaluation is needed. After SUD treatment, the diagnosis of ADHD generally remains stable, but ADHD subtype presentations are not. Some evidence supports pharmacological treatment with long-acting stimulants in higher than usual dosages. Studies on psychological treatment remain scarce, but there are some promising findings on integrated cognitive behaviour therapy.

SUMMARY

Diagnosis and treatment of patients with comorbid ADHD and SUD remain challenging. As ADHD presentations can change during active treatment, an active follow-up is warranted to provide treatment to the individuals' personal strengths and weaknesses.

Age-Normative Pathways of Striatal Connectivity Related to Clinical Symptoms in the General Population

BACKGROUND

Altered striatal development contributes to core deficits in motor and inhibitory control, impulsivity, and inattention associated with attention-deficit/hyperactivity disorder and may likewise play a role in deficient reward processing and emotion regulation in psychosis and depression. The maturation of striatal connectivity has not been well characterized, particularly as it relates to clinical symptomatology.

METHODS

Resting-state functional connectivity with striatal subdivisions was examined for 926 participants (8-22 years of age, 44% male) from the general population who had participated in two large cross-sectional studies. Developing circuits were identified and growth charting of age-related connections was performed to obtain individual scores reflecting relative neurodevelopmental attainment. Associations of clinical symptom scales (attention-deficit/hyperactivity disorder, psychosis, depression, and general psychopathology) with the resulting striatal connectivity age-deviation scores were then tested using elastic net regression.

RESULTS

Linear and nonlinear developmental patterns occurred across 231 striatal age-related connections. Both unique and overlapping striatal age-related connections were associated with the four symptom domains. Attention-deficit/hyperactivity disorder severity was related to age-advanced connectivity across several insula subregions, but to age-delayed connectivity with the nearby inferior frontal gyrus. Psychosis was associated with advanced connectivity with the medial prefrontal cortex and superior temporal gyrus, while aberrant limbic connectivity predicted depression. The dorsal posterior insula, a region involved in pain processing, emerged as a strong contributor to general psychopathology as well as to each individual symptom domain.

CONCLUSIONS

Developmental striatal pathophysiology in the general population is consistent with dysfunctional circuitry commonly found in clinical populations. Atypical age-normative connectivity may thereby reflect aberrant neurodevelopmental processes that contribute to clinical risk.

A review of the effects of nicotine on social functioning

Many smokers are aware that smoking is a dangerous health behavior and eventually try to quit smoking. Unfortunately, most quit attempts end in failure. Traditionally, the addictive nature of smoking has been attributed to the pharmacologic effects of nicotine. In an effort to offer a more comprehensive, biobehavioral analysis of smoking behavior and motivation, some researchers have begun to consider the role of social factors in smoking. In line with recent recommendations to integrate social and pharmacological analyses of smoking, we reviewed the experimental literature examining the effects of nicotine and nicotine withdrawal on social functioning. The review identified 13 studies that experimentally manipulated nicotine and assessed social functioning, 12 of which found support for nicotine's enhancement of social functioning. Although few experiments have investigated social functioning, they nevertheless offer compelling evidence that nicotine enhances social functioning in smokers and suggest that nicotine deprivation may hamper social functioning in those dependent on nicotine. Future directions for investigating social outcomes and context in those who use nicotine products are discussed with a focus on leveraging advances in social and developmental psychology, animal research, sociology, and neuroimaging to more comprehensively understand smoking behavior. (PsycINFO Database Record (c) 2018 APA, all rights reserved).