Food images engage subliminal motivation to seek food

Human eating behaviour is motivated and shaped by a complex interaction of internal drives such as hunger, external influences such as environmental cues and the sensory properties of food itself. Thus, as is demonstrated by the example of sensory-specific satiety (SSS), hunger may be reduced but particular foods (for example, desserts) retain their attraction and their ability to prompt consumption. In considering consumption, and overconsumption, it is therefore important to understand the interaction between internal and external drives to eat. Using grip force as a measure of motivation, we examined this interaction using an SSS manipulation. Critically, we sought to determine whether food stimuli would exert their influence even when they were subliminally presented (and thus not accessible to consciousness), and whether this unconscious influence would be flexibly updated in response to changes in food reward value with satiety. Demonstrating that the SSS effect remains when external stimuli are not consciously perceived, our data highlight the importance of even the most subtle, fleeting and even subliminal external events in shaping our motivation towards food.     

Reserpine modulates neurotransmitter release to extend lifespan and alleviate age-dependent Aβ proteotoxicity in Caenorhabditis elegans

Aging is a debilitating process often associated with chronic diseases such as diabetes, cardiovascular and neurodegenerative diseases like Alzheimer's disease (AD). AD occurs at a very high incidence posing a huge burden to the society. Model organisms such as C. elegans become essential to understand aging or lifespan extension - the etiology, molecular mechanism and identification of new drugs against age associated diseases. The AD model, manifesting Aβ proteotoxicity, in C. elegans is well established and has provided valuable insights. Earlier, we have reported that Reserpine, an FDA-approved antihypertensive drug, increases C. elegans lifespan with a high quality of life and ameliorates Aβ toxicity in C. elegans. But reserpine does not seem to act through the known lifespan extension pathways or inhibition of its known target, vesicular monoamine transporter, VMAT. Reserpine's mode of action and the pathways it activates are not known. Here, we have evaluated the presynaptic neurotransmitter(s) release pathway and identified acetylcholine (ACh) as the crucial player for reserpine's action. The corroborating evidences are: i) lack of lifespan extension in the ACh loss of function (hypomorphic) - synthesis (cha-1) and transport (unc-17) mutants; ii) mitigation of chronic aldicarb effect; iii) lifespan extension in dopamine (cat-2) and dopamine and serotonin (bas-1) biosynthetic mutants; iv) no rescue from exogenous serotonin induced paralysis in the AD model worms; upon reserpine treatment. Thus, modulation of acetylcholine is essential for reserpine's action.     

Prevalence and correlates of alcohol use disorders in the Singapore Mental Health Survey

Aims To establish the prevalence, correlates, comorbidity and treatment gap of alcohol use disorders in the Singapore resident population. Design The Singapore Mental Health Study is a cross‐sectional epidemiological survey. Setting A nationally representative survey of the resident (citizens and permanent residents) population in Singapore. Participants A total of 6616 Singaporean adults aged 18 years and older. Measurements The diagnoses were established using the World Mental Health Composite International Diagnostic Interview (WMH‐CIDI) diagnostic modules for life‐time and 12‐month prevalence of selected mental illnesses including alcohol use disorders. Findings The life‐time prevalence of alcohol abuse and alcohol dependence was 3.1% and 0.5%, while the 12‐month prevalence of alcohol abuse and alcohol dependence was 0.5% and 0.3%, respectively. The life‐time and 12‐month prevalence of alcohol use disorders was 3.6% and 0.8%, respectively. Those with alcohol use disorder had significantly higher odds of having major depressive disorder [odds ratio (OR) 3.1] and nicotine dependence (OR 4.5). Compared to the rest of the population, those with an alcohol use disorder had significantly higher odds of having gastric ulcers (OR 3.0), respiratory conditions (OR 2.1) and chronic pain (OR 2.1). Only one in five of those with alcohol use disorder had ever sought treatment. Conclusions The prevalence of alcohol use disorders is relatively low in the Singapore adult population. Comorbidity with mental and physical disorders is significant, emphasizing the need to screen people with alcohol use disorders for these comorbidities.     

Mental disorders: employment and work productivity in Singapore

Aim

To examine the association between mental disorders and work disability in the adult resident population in Singapore.

Method

Data are from the Singapore Mental Health Study, which was a household survey of a nationally representative sample. The main instrument used was the Composite International Diagnostic Interview (CIDI). Employment-related information was collected using the modified employment module of the CIDI.

Results

A total of 6,429 respondents were included in the analysis, 71 % (n = 4,594) were employed, 24.5 % (n = 1,522) were economically inactive and 4.5 % (n = 313) were unemployed. Among the employed, 2.3 % had a 12-month prevalence of at least one mental disorder, while 5.3 % of the unemployed had at least one mental disorder. The average number of work loss days (absenteeism) per capita among those with a mental disorder was 0.5 per month that is equivalent to an annualized national projection of approximately 0.3 million productivity days. The average work-cutback days (presenteeism) were 0.4 days among this group. Of the mentally ill in the workforce, a high proportion (86.5 %) did not ever seek help for problems related to mental health.

Conclusion

Our findings provide information on the significant consequences of mental disorders on the workforce in terms of lost work productivity, which could pave the way for a more rational allocation of scarce resources.     

Variable selection for discrete survival model with frailty in presence of left truncation and right censoring: Studying association of environmental toxicants on time-to-pregnancy

Understanding the association between mixtures of environmental toxicants and time-to-pregnancy (TTP) is an important scientific question as sufficient evidence has emerged about the impact of individual toxicants on reproductive health and that individuals are exposed to a whole host of toxicants rather than an individual toxicant. Assessing mixtures of chemical effects on TTP poses significant statistical challenges, namely (i) TTP being a discrete survival outcome, typically subject to left truncation and right censoring, (ii) chemical exposures being strongly correlated, (iii) appropriate transformation to account for some lipid-binding chemicals, (iv) non-linear effects of some chemicals, and (v) high percentage of concentration below the limit of detection (LOD) for some chemicals. We propose a discrete frailty modeling framework (named Discnet) that allows selection of correlated covariates while appropriately addressing the methodological issues mentioned above. Discnet is shown to have better and stable false negative and false positive rates compared to alternative methods in various simulation settings. We did a detailed analysis of the pre-conception endocrine disrupting chemicals and TTP from the LIFE study and found that older females, female exposure to cotinine (smoking), DDT conferred a delay in getting pregnant, which was consistent across various approaches to account for LOD as well as non-linear associations.