Where alcohol use disorder meets interoception: A meta-analytic view on structural and functional neuroimaging data

Alcohol use disorder (AUD) has been associated with changes in the processing of internal body signals, known as interoception. Changes in brain structure, particularly in the insula, are thought to underlie impaired interoception. As studies specifically investigating this association are largely lacking, this analysis takes an approach that compares meta-analytic results on interoception with recently published meta-analytic results on gray matter reduction in AUD. A systematic literature search identified 25 eligible interoception studies. Activation likelihood estimation (ALE) was used to test for spatial convergence of study results. Overlap between interoception and AUD clusters was tested using conjunction analysis. Meta-analytic connectivity modeling (MACM) and resting-state functional connectivity were used to identify the functional network of interoception and to test where this network overlapped with AUD meta-analytic clusters. The results were characterized using behavioral domain analysis. The interoception ALE identified a cluster in the left middle insula. There was no overlap with clusters of reduced gray matter in AUD. MACM analysis of the interoception cluster revealed a large network located in the insulae, thalami, basal nuclei, cingulate and medial frontal cortices, and pre- and postcentral gyri. Resting state analysis confirmed this result, showing the strongest connections to nodes of the salience- and somatomotor network. Five of the eight clusters that showed a structural reduction in AUD were located within these networks. The behavioral profiles of these clusters were suggestive of higher-level processes such as salience control, somatomotor functions, and skin sensations. The results suggest an altered salience mapping of interoceptive signals in AUD, consistent with current models. Connections to the somatomotor network may be related to action control and integration of skin sensations. Mindfulness-based interventions, pleasurable touch, and (deep) transcranial magnetic stimulation may be targeted interventions that reduce interoceptive deficits in AUD and thus contribute to drug use reduction and relapse prevention.

Neural underpinnings of response inhibition in substance use disorders: weak meta-analytic evidence for a widely used construct

RATIONALE

Substance use disorders (SUDs) rank among the most severely debilitating psychiatric conditions. Among others, decreased response inhibition capacities could make it more difficult for patients to abstain from drug use and maintain abstinence. However, meta-analyses on the neural basis of response inhibition in SUDs yielded conflicting results.

OBJECTIVE

In this study, we revisited the neuroimaging research field and summarized the existing fMRI literature on overt response inhibition (Go/NoGo and stop-signal paradigms) across different SUDs.

METHODS

We performed a systematic literature review and an activation likelihood estimation (ALE) meta-analysis to investigate the actual convergence of functional deviations observed in SUD samples. Results were further supplied by consecutive robustness measures and a post-hoc random-effects meta-analysis of behavioural data.

RESULTS

We identified k = 21 eligible studies for our analysis. The ALE analysis indicated a significant cluster of convergence with its statistical peak in the right anterior insula. Consecutive analyses, however, indicated this result was not robust and susceptible towards publication bias. Additionally, a post-hoc random effects meta-analysis of the behavioural parameters of Go/NoGo and stop-signal paradigms reported by the included studies revealed no significant differences in task performance comparing SUD samples and controls.

CONCLUSION

We discuss that the role of task-based response inhibition may require some refinement as an overarching marker for SUD pathology. Finally, we give a few prospects for future research that should be further explored in this context.

A Four-Item Questionnaire to Measure Problematic Social Media Use: The Social Media Disorder Test

While the use of video games and social media is an enjoyable recreational activity for most users, a minority develop problematic patterns of use. In the ICD-11, for the first time, there is a category of "disorders due to addictive behaviors" (including gaming disorder). The scientific literature also suggests a potential for the problematic use of social media. Economic screening tools for this are still needed. A very economical questionnaire to record gaming disorder is the ICD-11-based Gaming Disorder Test (GDT). The purpose of the present survey was to investigate the psychometric properties of an adapted questionnaire (Social Media Disorder Test, SMDT) to assess problematic social media use (PSMU). Therefore, 443 youths (mean age: 20.11 years) were examined with the SMDT and other measures regarding PSMU, self-control, and psychopathology. A confirmatory factor analysis (CFA) and reliability and correlation analyses were conducted. For the SMDT, we observed very good fit indices in the CFA, suggesting a one-factor structure; the reliability coefficient was 0.90, and we found the first indications for criterion validity. If the results can be confirmed, the SMDT, with its four questions, would be a very economical instrument to measure PSMU based on the ICD-11 criteria for behavioral addictions.

The Big Five Personality Domains and Their Facets: Empirical Relations to Problematic Use of Video Games, Social Media and Alcohol

Relatively common behavioral patterns in adolescence are problematic use of video games (PG), social media (PSMU) or alcohol (PAU). According to theoretical models, personality traits are relevant for Internet-related problematic behaviors. In the present study, associations of the Big Five personality domains and their 15 facets with PG, PSMU and PAU were compared for the first time. Therefore, 492 adolescents (mean age: 16.83 years) were examined with the established Big Five Inventory-2 as well as other standardized questionnaires on PG, PSMU and PAU. For statistical evaluation, correlation analyses were used as bivariate procedures and multiple regression analyses as multivariable procedures. At the personality domain level, consistently in bivariate and multivariate analyses, statistically significant associations between higher Negative Emotionality (Neuroticism) and PG, PSMU and PAU as well as between lower Open-Mindedness and PG and PAU were observed. At the level of facets, higher Anxiety (facet of Negative Emotionality) was related to PG and PSMU as well as lower Aesthetic Sensitivity (facet of Open-Mindedness) and lower Productiveness (facet of Conscientiousness) to PG. Considering the overlap of 95% confidence intervals, very comparable patterns of associations between PG, PSMU and PAU and the Big Five and their facets were observed in adolescence (indicating similarities in etiology).

A coordinate-based meta-analysis of white matter alterations in patients with alcohol use disorder

INTRODUCTION

Besides the commonly described gray matter (GM) deficits, there is growing evidence of significant white matter (WM) alterations in patients with alcohol use disorder (AUD). WM changes can be assessed using volumetric and diffusive magnetic resonance imaging methods, such as voxel-based morphometry (VBM) and diffusion tensor imaging (DTI). The aim of the present meta-analysis is to investigate the spatial convergence of the reported findings on WM alterations in AUD.

METHODS

Systematic literature search on PubMed and further databases revealed 18 studies eligible for inclusion, entailing a total of 462 AUD patients and 416 healthy controls (up to January 18, 2021). All studies that had used either VBM or DTI whole-brain analyzing methods and reported results as peak-coordinates in standard reference space were considered for inclusion. We excluded studies using approaches non-concordant with recent guidelines for neuroimaging meta-analyses and studies investigating patient groups with Korsakoff syndrome or other comorbid substance use disorders (except tobacco).

RESULTS

Anatomical likelihood estimation (ALE) revealed four significant clusters of convergent macro- and microstructural WM alterations in AUD patients that were assigned to the genu and body of the corpus callosum, anterior and posterior cingulum, fornix, and the right posterior limb of the internal capsule.

DISCUSSION

The changes in WM could to some extent explain the deteriorations in motor, cognitive, affective, and perceptual functions seen in AUD. Future studies are needed to clarify how WM alterations vary over the course of the disorder and to what extent they are reversible with prolonged abstinence.

Effect of different exercise protocols on histone acetyltransferases and histone deacetylases activities in rat hippocampus

Regular and moderate exercise has been considered an interesting neuroprotective strategy. Although the mechanisms by which physical exercise alters brain function are not clear, it appears that neuroprotective properties of exercise could be related to chromatin remodeling, specifically the induction of histone acetylation through modulation of histone deacetylases (HDAC) and histone acetyltransferases (HAT) activities. The aim of the present work was to investigate the effect of exercise on HDAC and HAT activities in rat whole hippocampus at different times after treadmill. Adult male Wistar rats were assigned to non-exercised (sedentary) and exercised groups on different protocols: a single session of treadmill exercise (running for 20 min) and a chronic treadmill protocol (running once daily for 20 min, for 2 weeks). The effects of exercise on HDAC and HAT activities were measured immediately, 1 h and 18 h after the single session or the last training session of chronic treadmill exercise using specific assay kits. The single session of treadmill exercise reduced HDAC activity, increased HAT activity and increased the HAT/HDAC balance in rat hippocampus immediately and 1 h after exercise, an indicative of histone hyperacetylation status. The acetylation balance was also influenced by the circadian rhythm, since the HAT/HDAC ratio was significantly decreased in the early morning in all groups when compared to the afternoon. These data support the hypothesis that exercise neuroprotective effects may be related, at least in part, to acetylation levels through modulation of HAT and HDAC activities. We also demonstrated circadian changes in the HAT and HDAC activities and, consequently, in the acetylation levels.

Transthoracic fine-needle aspiration in the aetiological diagnosis of community-acquired pneumonia

Clin Microbiol Infect 2010; 16: 909–911

Abstract

To investigate the safety and practicability of conducting transthoracic fine‐needle aspiration (TFNA) in a general hospital setting, we applied the TFNA procedure to 20 patients hospitalized with community‐acquired pneumonia (CAP) within 36 h of admission. Also, a preliminary assessment was made of the potential value of adding TFNA to conventional methods of diagnostic microbiology. TFNA was easy to perform and caused little discomfort, and no serious adverse events were observed. In spite of ongoing antimicrobial treatment, a likely aetiological diagnosis was established for 14 of 20 (70%) of the patients. TFNA may provide important additional information on the aetiology of CAP.

Prognostic score systems and community-acquired bacteraemic pneumococcal pneumonia

The aim of this study was to evaluate the accuracy of three score systems: the pneumonia severity index (PSI); CURB-65 (confusion; urea >7 mM; respiratory rate > or =30 breaths x min(-1); blood pressure <90 mmHg systolic or < or =60 mmHg diastolic; aged > or =65 yrs old); and modified American Thoracic Society rule for predicting intensive care unit (ICU) need and mortality due to bacteraemic pneumococcal pneumonia. All adult patients (n = 114) with invasive pneumococcal pneumonia at the Karolinska University Hospital, Sweden, 1999-2000, were included in the study. Severity scores were calculated and the independent prognostic importance of different variables was analysed by multiple regression analyses. PSI > or = IV, CURB-65 > or = 2, and the presence of one major or more than one minor risk factor in mATS all had a high sensitivity, but somewhat lower specificity for predicting death and ICU need. The death rate was 12% (13 out of 114). Severity score and treatment in departments other than the Dept of Infectious Diseases were the only factors independently correlated to death. Patients treated in other departments more often had severe underlying illnesses and were more severely ill on admission. However, a significant difference in death rates remained after adjustment for severity between the two groups. In conclusion, all score systems were useful for predicting the need for intensive care unit treatment and death due to bacteremic pneumococcal pneumonia. The pneumonia severity index was the most sensitive, but CURB-65 was easier to use.

Clonal and Capsular Types Decide Whether Pneumococci Will Act as a Primary or Opportunistic Pathogen

BACKGROUND

Streptococcus pneumoniae is a major cause of morbidity and mortality worldwide. The role of the different capsular and clonal types in invasive disease severity remains to be defined.

METHODS

Disease severity and disease type were correlated to age, underlying disease, capsular serotype, and clonal type of the causative agent for 494 adult patients with invasive pneumococcal disease.

RESULTS

Pneumococcal isolates of serotypes 1 and 7F were genetically homogenous, had the highest potential to infect previously healthy individuals, and were not causing deaths. Also, type 1 isolates were only found among younger adults, whereas other serotypes were mainly found among elderly persons (e.g., type 23F). Some serotypes and/or clones were more prone to cause more-severe disease, as observed by high APACHE II scores calculated at admission, and were also associated with a high mortality (e.g., clones of type 3 and 11A). We found no evidence of an impact of penicillin resistance on disease severity and disease type.

CONCLUSIONS

We suggest that clones with capsular types 1 and 7F, which are known to have a high invasive disease potential, behave as primary pathogens, whereas clones with other capsular types with a lower relative risk of causing invasive disease are more opportunistic, primarily affecting patients with underlying disease. Disease caused by the latter group, however, was more severe, even in previously healthy individuals.