Approach-alcohol action tendencies can be inhibited by cognitive load

Rationale

Dysregulated alcohol consumption has been attributed to an imbalance between an approach-alcohol action tendency and executive control processes. However, which specific executive control processes are involved is not known. One candidate executive process is interference suppression, which refers to the suppression of task-irrelevant information through the active maintenance of task-relevant information or a cognitive load.

Objective

The present study aimed to (1) establish whether alcohol action tendency can be inhibited by interference suppression through the use of cognitive loads and (2) to assess whether individual differences in the degree of interference suppression from cognitive loads is related to individual differences in the ability to regulate alcohol consumption.

Method

Two groups of social drinkers (total N?=?58) who differed in their ability to regulate their alcohol consumption completed a novel cognitive load variant of the approach avoidance task (AAT) and an alcohol taste test.

Results

Results indicated that (1) there was a relationship between alcohol bias on the AAT and alcohol consumption under low load, but not high load, consistent with the hypothesis that the action tendency would be inhibited through interference suppression, and (2) this effect of load was not modified by drinking group, with both groups demonstrating equivalent ability to inhibit the action tendency.

Conclusions

The present findings suggest that alcohol action tendency can be inhibited through interference suppression, and that this is effective even for those that have difficulty regulating their alcohol consumption.     

Management of children exposed to Mycobacterium tuberculosis: a public health evaluation in West Java,Indonesia

Objective

To investigate qualitatively and quantitatively the performance of a programme for managing the child contacts of adult tuberculosis patients in Indonesia.

Methods

A public health evaluation framework was used to assess gaps in a child contact management programme at a lung clinic. Targets for programme performance indicators were derived from established programme indicator targets, the scientific literature and expert opinion. Compliance with tuberculosis screening, the initiation of isoniazid preventive therapy in children younger than 5 years, the accuracy of tuberculosis diagnosis and adherence to preventive therapy were assessed in 755 child contacts in two cohorts. In addition, 22 primary caregivers and 34 clinic staff were interviewed to evaluate knowledge and acceptance of child contact management. The cost to caregivers was recorded. Gaps between observed and target indicator values were quantified.

Findings

The gaps between observed and target performance indicators were: 82% for screening compliance; 64 to 100% for diagnostic accuracy, 50% for the initiation of preventive therapy, 54% for adherence to therapy and 50% for costs. Many staff did not have adequate knowledge of, or an appropriate attitude towards, child contact management, especially regarding isoniazid preventive therapy. Caregivers had good knowledge of screening but not of preventive therapy and had difficulty travelling to the clinic and paying costs.

Conclusion

The study identified widespread gaps in the performance of a child contact management system in Indonesia, all of which appear amenable to intervention. The public health evaluation framework used could be applied in other settings where child contact management is failing.     

Implicit and explicit self-esteem as concurrent predictors of suicidal ideation, depressive symptoms, and loneliness

The aim of the present study was to examine whether explicit and implicit self-esteem, the interaction between these two constructs, and their discrepancy are associated with depressive symptoms, suicidal ideation, and loneliness. Participants were 95 young female adults (M = 21.2 years, SD = 1.88) enrolled in higher education. We administered the Name Letter Task to measure implicit self-esteem, and the Rosenberg self-esteem scale to assess explicit self-esteem. The results indicated that explicit but not implicit self-esteem was negatively associated with depressive symptoms, suicidal ideation, and loneliness. The interaction of implicit and explicit self-esteem was associated with suicidal ideation, indicating that participants with high implicit self-esteem combined with a low explicit self-esteem showed more suicidal ideation. Furthermore, the size of the discrepancy between implicit and explicit self-esteem was positively associated with depressive symptoms, suicidal ideation, and loneliness. In addition, results showed that the direction of the discrepancy is an important: damaged self-esteem (high implicit self-esteem combined with low explicit self-esteem) was consistently associated with increased levels of depressive symptoms, suicidal ideation, and loneliness, while defensive or fragile self-esteem (high explicit and low implicit self-esteem) was not. Together, these findings provide new insights into the relationship of implicit and explicit self-esteem with depressive symptoms, suicidal ideation, and loneliness.     

Enhancement of selective attention by tDCS: interaction with interference in a Sternberg task

The amyloid β (Aβ) protein is believed to be the key pathological mediator of Alzheimer's disease (AD) which is the first and most well known type of dementia. Despite a growing body of evidence indicating that Aβ neurotoxicity induces changes in synaptic function, little effort, if any, has been made to investigate the effect of in vivo Aβ treatment on intrinsic neuronal properties. The present study was designed to examine the effects that in vivo Aβ treatment have on the intrinsic repetitive firing properties of CA1 pyramidal neurons, using whole cell patch clamp recording. Protective effect of cannabinoid CB1 receptor activation was also investigated against Aβ-induced alterations in evoked electrophysiological activities. The findings from present study demonstrated that a bilateral injection of Aβ into the prefrontal cortex causes robust changes in activity-dependent electrophysiological responses in hippocampal CA1 pyramidal neurons. The effects of Aβ treatment alone was almost completely prevented by combined treatment with Aβ and ACEA, a selective CB1 receptor agonist. It can be concluded Aβ treatment reduces evoked neuronal activity and activation of CB1 cannabinoid receptors may have beneficial preventative effects on Aβ-induced electrophysiological changes.     

Low cost HIV-1 quantitative RT-PCR assay in resource-limited settings: improvement and implementation

Monitoring of HIV viral load in low and middle income settings is limited by high cost of the commercial assays. Therefore, we developed a novel RT-PCR quantitative assay was developed. This assay targets the HIV-1 pol integrase gene (INT). Subsequently, the performance of the INT assay, described previously as a Long Terminal Repeat (LTR) assay and a combined INT/LTR dual target RT-PCR assay was compared. The LTR-assay was found to be sensitive and cost-effective (50-70% cheaper than commercial assays) with the lowest coefficient of variation (%CV). Introduction of an internal standard further improved assay reliability. Therefore, this LTR assay was implemented in West Java, Indonesia. Linearity and precision of the LTR assay were good: %CV ranged from 1.0% to 10.4%. The limit of quantitation was 616 copies/ml. Performance was comparable with the commercial assay (Abbott assay) (r(2)=0.01), although on average the viral loads were 0.39 log(10)copies/ml lower. In clinical practice, it had excellent capability for monitoring treatment failure, the positive predictive value was 99% and the negative predictive value was 93%. In conclusion, the implementation of the improved HIV-1 viral load LTR-assay for routine diagnosis in resource poor settings can be a good alternative when commercial assays are unaffordable.     

Alcohol-Induced Changes in Conflict Monitoring and Error Detection as Predictors of Alcohol Use in Late Adolescence

Adolescence is a vulnerable period for the development of substance use and related problems. Understanding how exposure to drugs influences the adolescent brain could reveal mechanisms underlying risk for addiction later in life. In the current study, 87 adolescents (16–20-year olds; the local legal drinking age was16, allowing the inclusion of younger subjects than usually possible) underwent EEG measurements during a Go/No-Go task with and without alcohol cues; after placebo and a low dose of alcohol (0.45 g/kg). Conflict monitoring and error detection processes were investigated with the N2 and the error-related negativity (ERN) ERP components. Participants were followed-up after 6 months to assess changes in alcohol use. The NoGo-N2 was larger for alcohol cues and acute alcohol decreased the amplitude of the NoGo-N2 for alcohol cues. ERN amplitude was blunted for alcohol cues. Acute alcohol decreased the amplitude of the ERN, specifically for control cues. Furthermore, the differences in ERN for alcohol cues between the placebo and alcohol conditions predicted alcohol use 6 months later: subjects who showed stronger blunting of the ERN after acute alcohol were more likely to return to more moderate drinking patterns. These results suggest that cues signalling reward opportunities might activate a go-response mode and larger N2 (detection of increased conflict) for these cues might be necessary for inhibition. The ERN results suggest a deficiency in the monitoring system for alcohol cues. Finally, a lack of alcohol-induced deterioration of error monitoring for cues with high salience might be a vulnerability factor for alcohol abuse in adolescents.