ResearchPad - young-adults https://www.researchpad.co Default RSS Feed en-us © 2020 Newgen KnowledgeWorks <![CDATA[Recreational drug use among Nigerian university students: Prevalence, correlates and frequency of use]]> https://www.researchpad.co/article/elastic_article_15734 Given the paucity of data on recreational drug use and the recent media attention on the abuse of drugs such as codeine cough syrups and tramadol, in Nigeria, our study examined the prevalence and frequency of recreational drug use among young adults from two Nigerian universities. We drew from the Socio-ecological Model to examine the influence of factors at the individual and family level on recreational drug use among adolescents and young adults.MethodsThis cross-sectional study was conducted between February and March 2018 among a final sample of 784 male and female university students selected using stratified random sampling. Binary logistic regression was used to identify significant predictors of ever use and current use of drugs.ResultsOur analyses showed that 24.5% of students had ever used drugs for recreational purposes, and 17.5% are current users. The median drug use frequency over the past month was six days among current users (n = 137). In the multivariable analyses, living in the same household as one's mother (AOR 0.28 95% CI 0.16–0.49), adequate family support (AOR 0.48 95% CI 0.26–0.89) and frequent attendance of religious fellowships (AOR 0.13 95% CI 0.07–0.25) were significantly associated with a lower likelihood of recreational drug use. However, male sex (AOR 1.52 95% CI 1.05–2.21) was associated with higher odds of recreational drug use.ConclusionThe family should be considered as an important unit to sensitize young people on the harmful effects of drug use. It is also vital that religious leaders speak against drug use in their various fellowships. There is a need to address recreational drug use on Nigerian campuses by educating students about its adverse impacts. ]]> <![CDATA[Dynamic stability and stepping strategies of young healthy adults walking on an oscillating treadmill]]> https://www.researchpad.co/article/5c6dc9dad5eed0c48452a314

Understanding how people modify their stepping to maintain gait stability may provide information on fall risk and help to understand strategies used to reduce loss of balance. The purpose of this study was to identify the stepping strategies healthy young individuals select to maintain balance while walking on a destabilizing surface in various directions. A treadmill mounted on top of a 6 degree-of-freedom motion base was used to generate support surface oscillations in different degrees of freedom and amplitudes. Fifteen healthy young adults (21.3 ± 1.4 years) walked at self-selected speeds while continuous sinusoidal oscillations were imposed to the support surface in a one degree of freedom: rotation or translation in the mediolateral (ML) direction and rotation or translation in the anteroposterior (AP) direction, with each condition repeated at three different amplitudes. We compared step width, length, and frequency and the mean and variability of margin of stability (MoS) during each experimental walking condition with a control condition, in which the support surface was stationary. Subjects chose a common strategy of increasing step width (p < 0.001) and decreasing step length (p = 0.008) while increasing mediolateral MoS (p < 0.001), particularly during oscillations that challenged frontal plane control, with rotations of the walking surface producing the greatest changes to stepping.

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<![CDATA[The impact of bilingualism on executive functions and working memory in young adults]]> https://www.researchpad.co/article/5c6dc9a6d5eed0c484529f7c

A bilingual advantage in a form of a better performance of bilinguals in tasks tapping into executive function abilities has been reported repeatedly in the literature. However, recent research defends that this advantage does not stem from bilingualism, but from uncontrolled factors or imperfectly matched samples. In this study we explored the potential impact of bilingualism on executive functioning abilities by testing large groups of young adult bilinguals and monolinguals in the tasks that were most extensively used when the advantages were reported. Importantly, the recently identified factors that could be disrupting the between groups comparisons were controlled for, and both groups were matched. We found no differences between groups in their performance. Additional bootstrapping analyses indicated that, when the bilingual advantage appeared, it very often co-occurred with unmatched socio-demographic factors. The evidence presented here indicates that the bilingual advantage might indeed be caused by spurious uncontrolled factors rather than bilingualism per se. Secondly, bilingualism has been argued to potentially affect working memory also. Therefore, we tested the same participants in both a forward and a backward version of a visual and an auditory working memory task. We found no differences between groups in either of the forward versions of the tasks, but bilinguals systematically outperformed monolinguals in the backward conditions. The results are analysed and interpreted taking into consideration different perspectives in the domain-specificity of the executive functions and working memory.

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<![CDATA[Development of a preliminary in vitro drug screening assay based on a newly established culturing system for pre-adult fifth-stage Onchocerca volvulus worms]]> https://www.researchpad.co/article/5c4a305ed5eed0c4844bfe74

Background

The human filarial parasite Onchocerca volvulus is the causative agent of onchocerciasis (river blindness). It causes blindness in 270,000 individuals with an additional 6.5 million suffering from severe skin pathologies. Current international control programs focus on the reduction of microfilaridermia by annually administering ivermectin for more than 20 years with the ultimate goal of blocking of transmission. The adult worms of O. volvulus can live within nodules for over 15 years and actively release microfilariae for the majority of their lifespan. Therefore, protracted treatment courses of ivermectin are required to block transmission and eventually eliminate the disease. To shorten the time to elimination of this disease, drugs that successfully target macrofilariae (adult parasites) are needed. Unfortunately, there is no small animal model for the infection that could be used for discovery and screening of drugs against adult O. volvulus parasites. Here, we present an in vitro culturing system that supports the growth and development of O. volvulus young adult worms from the third-stage (L3) infective stage.

Methodology/Principal findings

In this study we optimized the culturing system by testing several monolayer cell lines to support worm growth and development. We have shown that the optimized culturing system allows for the growth of the L3 worms to L5 and that the L5 mature into young adult worms. Moreover, these young O. volvulus worms were used in preliminary assays to test putative macrofilaricidal drugs and FDA-approved repurposed drugs.

Conclusion

The culture system we have established for O. volvulus young adult worms offers a promising new platform to advance drug discovery against the human filarial parasite, O. volvulus and thus supports the continuous pursuit for effective macrofilaricidal drugs. However, this in vitro culturing system will have to be further validated for reproducibility before it can be rolled out as a drug screen for decision making in macrofilaricide drug development programs.

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<![CDATA[Magnitude of road traffic accident related injuries and fatalities in Ethiopia]]> https://www.researchpad.co/article/5c59fea3d5eed0c4841351e4

Background

In many developing countries there is paucity of evidence regarding the epidemiology of road traffic accidents (RTAs). The study determines the rates of injuries and fatalities associated with RTAs in Ethiopia based on the data of a recent national survey.

Methods

The study is based on the secondary data of the Ethiopian Demographic and Health Survey conducted in 2016. The survey collected information about occurrence injuries and accidents including RTAs in the past 12 months among 75,271 members of 16,650 households. Households were selected from nine regions and two city administrations of Ethiopia using stratified cluster sampling procedure.

Results

Of the 75,271 household members enumerated, 123 encountered RTAs in the reference period and rate of RTA-related injury was 163 (95% confidence interval (CI): 136–195) per 100,000 population. Of the 123 causalities, 28 were fatal, making the fatality rate 37 (95% CI: 25–54) per 100,000 population. The RTA-related injuries and fatalities per 100,000 motor vehicles were estimated as 21,681 (95% CI: 18,090–25,938) and 4,922 (95% CI: 3325–7183), respectively. Next to accidental falls, RTAs were the second most common form of accidents and injuries accounting for 22.8% of all such incidents. RTAs contributed to 43.8% of all fatalities secondary to accidents and injuries. Among RTA causalities, 21.9% were drivers, 35.0% were passenger vehicle occupants and 36.0% were vulnerable road users including: motorcyclists (21.0%), pedestrians (12.1%) and cyclists (2.9%). Approximately half (47.1%) of the causalities were between 15–29 years of age and 15.3% were either minors younger than 15 years or seniors older than 64 years of age. Nearly two-thirds (65.0%) of the victims were males.

Conclusion

RTA-related causalities are extremely high in Ethiopia. Male young adults and vulnerable road users are at increased risk of RTAs. There is a urgent need for bringing road safety to the country's public health agenda.

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<![CDATA[HIV prevalence and determinants of loss-to-follow-up in adolescents and young adults with tuberculosis in Cape Town]]> https://www.researchpad.co/article/5c63392bd5eed0c484ae6139

TB remains a leading cause of mortality and morbidity in sub-Saharan Africa, due to the HIV epidemic. As TB treatment is lengthy, the completion of the full course of treatment may be especially challenging for young people. We therefore aimed to identify the extent of and reasons underlying loss to follow-up from TB treatment among young people in Cape Town. Accordingly, we reviewed the outcomes of young people treated for TB in Cape Town during 2009–2013, across three age groups: younger adolescents (10–14 years); older adolescents; (15–19 years) and young adults (20–24 years). We employed logistic regression analysis to identify risk factors for loss from TB care. 23,737 patients aged 10–24 were treated for drug sensitive TB over the study period. Of these, the HIV co-infection prevalence was 18.5% for younger adolescents, 12.9% for older adolescents and 33.1% for young adults. From age 16, HIV prevalence increased disproportionately among young women: by age 22, over 50% of women were TB/HIV co-infected compared to 14% of men. TB treatment success (cure plus completion) was 84.4%, while 1.7% of patients died, 9.5% were lost-to follow-up and 0.4% failed treatment. Being an older adolescent (aOR 1.75 [95% CI: 1.38–2.21]) or young adult (aOR: 1.96 [95% CI: 1.57–2.45]) increased the risk of loss-to-follow up, relative to being a younger adolescent. Further risk factors for loss from TB care were male gender (aOR: 1.33 [95% CI:1.20–1.46]), being a TB/HIV co-infected young person (aOR 1.74 [95% CI: 1.57–1.93]) and having had prior treatment for TB (aOR 3.17 [95% CI 2.87–3.51]). We identified risk factors for loss to follow-up and highlighted the need to focus on HIV prevention and retention in TB care among young people. TB care tailored to the needs of young people could improve patient retention, similar to improved outcomes reported by youth friendly HIV clinics.

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<![CDATA[Association of attitudes towards genetically modified food among young adults and their referent persons]]> https://www.researchpad.co/article/5c61e900d5eed0c48496f613

Most research on consumer attitudes does not consider that attitudes are likely influenced by people with whom we have some relationship even though socioeconomic, psychological and political theories recognize the importance of referent individuals’ opinions in attitude formation. Knowledge on the role of referent individuals’ opinions in attitude formation could improve the understanding of consumer acceptance of foods frequently associated with health or other concerns. This article examines the association of attitudes towards genetically modified (GM) crops and foods between young adults and their referent individuals using data collected in 2016 via surveys from the Czech Republic, Russia and Ukraine. Loglinear models of cell counts in contingency tables reveal a positive association of GM food attitudes between young adults and their referent individuals. This association was stronger in Russia and the Czech Republic than it was in Ukraine and stronger between female young adults and their referent individuals than between males and their referent individuals. Concordance in GM food attitudes with mothers is significantly stronger than concordance with best friends but not significantly different from concordance with fathers.

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<![CDATA[Results from e-KISS: electronic-KIOSK Intervention for Safer Sex: A pilot randomized controlled trial of an interactive computer-based intervention for sexual health in adolescents and young adults]]> https://www.researchpad.co/article/5c521801d5eed0c484795fee

Introduction

Interactive computer-based interventions (ICBI) are potentially scalable tools for use in real-world settings to promote sexual health and prevent sexually transmitted infections (STIs) and unintended pregnancies. We developed and assessed the feasibility and acceptability of an ICBI for promoting adolescent and young adult sexual health, and the effectiveness of the intervention in reducing unprotected sex, STIs, and unintended pregnancy.

Methods

This pilot randomized controlled trial enrolled STI Clinic patients, in Seattle, Washington, who were 14–24 years old and reported unprotected vaginal sex during the last 2 months. Both the control and intervention group used a computerized survey to enter their sexual health and only the intervention group received the ICBI. The ICBI included personalized sexual health feedback from a physician avatar; instructive video modules advocating sexual health; and identification of one behavior to change. At 3-month follow-up, participants reported on interim sexual and pregnancy histories and underwent repeat STI testing. We assessed intervention impact on unprotected vaginal sex, number of sexual partners, incident STIs, and unintended pregnancy.

Results

Of 272 participants, 242 (89%) completed the study, of whom 65% were female. While these findings did not reach statistical significance, at 3-month follow-up, the intervention group reported a 33% lower rate of unprotected vaginal sex (no condom use) [IRR = 0.67, 95% CI: 0.44–1.02]; 29% fewer sex partners [IRR = 0.71, 95% CI: 0.50–1.03]; and 48% fewer STIs [IRR = 0.52, 95% CI: 0.25–1.08] when compared to the control group. Similarly, as compared to the control group, intervention females reported a lower rate of unprotected vaginal sex (no birth control) [IRR = 0.80, 95% CI: 0.47–1.35] and half as many unintended pregnancies (n = 5) versus control females (n = 10) [IRR = 0.51, 95% CI: 0.17–1.58]. In exploratory analyses, intervention females reported fewer partners [IRR = 0.71, 95% CI: 0.50–1.00] and a significantly lower rate of vaginal sex without condoms [IRR = 0.50, 95% CI: 0.30–0.85].

Conclusion

The intervention was acceptable to both males and females, and at 3-month follow-up, there were non-significant reductions in risk behavior for all outcomes. Among females, exploratory analysis showed a significant reduction in vaginal sex without condoms.

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<![CDATA[Methodologic approach to sampling and field-based data collection for a large-scale in-depth interview study: The Social Position and Family Formation (SPAFF) project]]> https://www.researchpad.co/article/5c478c74d5eed0c484bd26a6

Over the past several decades there have been dramatic shifts in demographic patterns pertaining to family formation, with declining and delayed marriage and childbearing, and increased cohabitation in the United States and other Western industrialized nations. These trends in family demography have been predominantly studied using large-scale datasets, which have identified total population and subgroup trends over time, including differences by age, gender, racial/ethnic, economic, educational, religious, and other characteristics. However, there is limited knowledge and understanding of how individuals across different levels of social position, as well as other important characteristics, make decisions around forming families. This lack of qualitative data on contemporary attitudes regarding family formation has hampered our ability to more completely understand the factors driving behaviors pertaining to the large-scale (ie, international) shifts in demographic trends. The Social Position and Family Formation (SPAFF) project is an in-depth interview study that used quantitative data to guide recruitment of a large sample for qualitative interview data collection on factors influencing different aspects of family formation among heterosexual females and males (18–35 years) in the context of individuals’ social position. This methodological paper describes the use of a ‘quantitatively-informed’ purposive sampling approach in a large metropolitan area to collect qualitative data (through in-depth interviews) from a large sample (n = 200), utilizing web-based tools for successful community-based recruitment and project management.

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<![CDATA[Depressive and socially anxious symptoms, psychosocial maturity, and risk perception: Associations with risk-taking behaviour]]> https://www.researchpad.co/article/5b8acded40307c144d0de059

Risk-taking behaviour and onset of mental illness peak in adolescence and young adulthood. This study evaluated the interconnectedness of the domains of risk-taking behaviour, mental health (symptoms of depression and social anxiety), psychosocial maturity, risk perception, age, and gender in a sample of 306 adolescents and young adults. Participants between the ages of 16 and 35 completed online self-report measures assessing risk-taking behaviour, depressive symptoms, socially anxious symptoms, psychosocial maturity and risk perception. Socially anxious symptoms, psychosocial maturity, and risk perception were directly associated with risk-taking behaviour. Correlations between depressive symptoms, socially anxious symptoms, and psychosocial maturity were found. Psychosocial maturity proved a better predictor of risk-taking behaviour than age in this cohort. The findings indicate that mental health impacts upon risk-taking behaviour and that consideration should be given to psychosocial maturity in attempts to reduce adolescent and young adult risk-taking behaviour.

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<![CDATA[More push from your push-off: Joint-level modifications to modulate propulsive forces in old age]]> https://www.researchpad.co/article/5b87837040307c3c45097670

Introduction

Compared to young adults, older adults walk with smaller propulsive forces and a redistribution to more proximal leg muscles for power generation during push-off. Despite this deficit in propulsive function, older adults can increase push-off intensity when encouraged to via real-time biofeedback. However, the specific joint-level modifications used by older adults to enhance propulsive force generation has yet to be elucidated. The purpose of this study was to identify the joint-level modifications used by young and older adults to modulate propulsive forces when walking at their preferred speed.

Methods

9 young and 16 older adults walked at their preferred speed while visual biofeedback prompted them to modulate their propulsive forces using targets prescribed at ±10% and ±20% of their preferred value. Older adults were then divided into groups exhibiting relatively larger or smaller baseline redistribution to more proximal leg muscles for power generation.

Results

Neither young nor either older adult cohort modulated propulsive forces by altering their peak ankle power generation. Instead, subjects increased trailing limb extension and attenuated mechanical power demands at the hip during push-off. Older adults that had a larger baseline redistribution exhibited larger responses to enhanced push-off intensity than their peers–for example, walking with 11% less hip flexor power and 10% more trailing limb extension during push-off when exerting larger than preferred propulsive forces.

Conclusion

Propulsive force biofeedback that elicits larger than preferred propulsive forces also increases trailing limb extension and attenuates mechanical power demands at the hip in older adults most exhibiting a distal-to-proximal redistribution. Our results suggest that considering baseline redistribution may be important in the personalized prescription of interventions aimed at enhancing walking performance by improving push-off intensity.

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<![CDATA[Walking the walk? Experiments on the effect of pledging to vote on youth turnout]]> https://www.researchpad.co/article/5b28b14b463d7e116be9c9ad

Psychological theories of political behavior suggest that commitments to perform a certain action can significantly increase the likelihood of such action, but this has rarely been tested in an experimental context. Does pledging to vote increase turnout? In cooperation with the Environmental Defense Fund during the 2016 election, we conduct the first randomized controlled trials testing whether young people who pledge to vote are more likely to turn out than those who are contacted using standard Get-Out-the-Vote materials. Overall, pledging to vote increased voter turnout by 3.7 points among all subjects and 5.6 points for people who had never voted before. These findings lend support for theories of commitment and have practical implications for mobilization efforts aimed at expanding the electorate.

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<![CDATA[Prevalence of Chlamydia in Young Adulthood and Association with Life Course Socioeconomic Position: Birth Cohort Study]]> https://www.researchpad.co/article/5989d9f1ab0ee8fa60b6e8b3

Background

Few estimates are available of chlamydia prevalence in the general population. Existing studies have limited scope to explore potential selection bias or associations with socioeconomic position.

Methods

We examined the prevalence of Chlamydia trachomatis infection and associations with life-course socioeconomic position in the Avon Longitudinal Study of Parents and Children in England. Chlamydia infection was measured through nucleic acid amplification test of urine specimens.

Results

4864 (51%) of those invited attended the clinic (mean age 17.8; SD 0.37 years). (60%) provided a urine specimen. Prevalence was 1.0% (95% CI 0.6 to 1.6) among participants reporting sexual activity. Risk of infection was strongly associated with life course social disadvantage and with recent sexual behaviour. After adjustment for other measures of disadvantage and for sexual behaviour the strongest risk factors for infection were lower maternal educational attainment (OR 9.1 (1.1, 76.7)) and lower participant educational attainment at age 11 (OR 5.0 (1.5, 16.5)). Both clinic attendance and agreement to test were lower amongst the disadvantaged. Adjustment for selective participation based on detailed information on non-participants approximately doubled prevalence estimates. Prevalence was higher in sexually active women (1.4% (0.7 to 2.4) than men (0.5% (0.1 to 1.3)).

Conclusions

Chlamydia prevalence in this general population sample was low even after adjustment for selective participation in testing. These estimates of prevalence and patterns of association with socioeconomic position may both reflect recent screening efforts. Prevalence was higher amongst the disadvantaged who were also less likely to engage in testing. Our results reveal the importance of monitoring and addressing inequalities in screening programme participation and outcomes.

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<![CDATA[Exposure to digital marketing enhances young adults’ interest in energy drinks: An exploratory investigation]]> https://www.researchpad.co/article/5989db51ab0ee8fa60bdc307

Young adults experience faster weight gain and consume more unhealthy food than any other age groups. The impact of online food marketing on “digital native” young adults is unclear. This study examined the effects of online marketing on young adults’ consumption behaviours, using energy drinks as a case example. The elaboration likelihood model of persuasion was used as the theoretical basis. A pre-test post-test experimental research design was adopted using mixed-methods. Participants (aged 18–24) were randomly assigned to control or experimental groups (N = 30 each). Experimental group participants’ attitudes towards and intended purchase and consumption of energy drinks were examined via surveys and semi-structured interviews after their exposure to two popular energy drink brands’ websites and social media sites (exposure time 8 minutes). Exposure to digital marketing contents of energy drinks improved the experimental group participants’ attitudes towards and purchase and consumption intention of energy drinks. This study indicates the influential power of unhealthy online marketing on cognitively mature young adults. This study draws public health attentions to young adults, who to date have been less of a focus of researchers but are influenced by online food advertising.

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<![CDATA[Larval crowding accelerates C. elegans development and reduces lifespan]]> https://www.researchpad.co/article/5989db5aab0ee8fa60bdf2c7

Environmental conditions experienced during animal development are thought to have sustained impact on maturation and adult lifespan. Here we show that in the model organism C. elegans developmental rate and adult lifespan depend on larval population density, and that this effect is mediated by excreted small molecules. By using the time point of first egg laying as a marker for full maturity, we found that wildtype hermaphrodites raised under high density conditions developed significantly faster than animals raised in isolation. Population density-dependent acceleration of development (Pdda) was dramatically enhanced in fatty acid β-oxidation mutants that are defective in the biosynthesis of ascarosides, small-molecule signals that induce developmental diapause. In contrast, Pdda is abolished by synthetic ascarosides and steroidal ligands of the nuclear hormone receptor DAF-12. We show that neither ascarosides nor any known steroid hormones are required for Pdda and that another chemical signal mediates this phenotype, in part via the nuclear hormone receptor NHR-8. Our results demonstrate that C. elegans development is regulated by a push-pull mechanism, based on two antagonistic chemical signals: chemosensation of ascarosides slows down development, whereas population-density dependent accumulation of a different chemical signal accelerates development. We further show that the effects of high larval population density persist through adulthood, as C. elegans larvae raised at high densities exhibit significantly reduced adult lifespan and respond differently to exogenous chemical signals compared to larvae raised at low densities, independent of density during adulthood. Our results demonstrate how inter-organismal signaling during development regulates reproductive maturation and longevity.

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<![CDATA[Tissue- and Time-Specific Expression of Otherwise Identical tRNA Genes]]> https://www.researchpad.co/article/5989d9dcab0ee8fa60b67ec1

Codon usage bias affects protein translation because tRNAs that recognize synonymous codons differ in their abundance. Although the current dogma states that tRNA expression is exclusively regulated by intrinsic control elements (A- and B-box sequences), we revealed, using a reporter that monitors the levels of individual tRNA genes in Caenorhabditis elegans, that eight tryptophan tRNA genes, 100% identical in sequence, are expressed in different tissues and change their expression dynamically. Furthermore, the expression levels of the sup-7 tRNA gene at day 6 were found to predict the animal’s lifespan. We discovered that the expression of tRNAs that reside within introns of protein-coding genes is affected by the host gene’s promoter. Pairing between specific Pol II genes and the tRNAs that are contained in their introns is most likely adaptive, since a genome-wide analysis revealed that the presence of specific intronic tRNAs within specific orthologous genes is conserved across Caenorhabditis species.

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<![CDATA[Marijuana Use Is Associated with Behavioral Approach and Depressive Symptoms in Adolescents and Emerging Adults]]> https://www.researchpad.co/article/5989daf0ab0ee8fa60bc0fbd

Background

Repeated CB1 binding due to THC results in downregulation of the endocannabinoid system in cortex and limbic regions, perhaps disrupting frontolimbic functioning. This is particularly a concern in young adults who are still undergoing neurodevelopment in frontal and limbic regions. Such disruptions may be linked to increased depressive symptoms, anxiety symptoms, and executive dysfunction, and decreased behavioral approach.

Objectives

Here we examine the influence of young adult marijuana use on anxiety, depressive symptoms, behavioral approach, and executive dysfunction. The influence of alcohol and gender were also assessed.

Methods

84 participants (42 MJ, 42 controls) aged 18–25 were balanced for gender (39 F). Exclusion criteria included: MRI contraindications, left handed, comorbid Axis-I disorders, major medical or neurologic disorders, prenatal issues, or prenatal alcohol/illicit drug exposure, or excessive other drug use. Participants completed the FrsBE, BIS/BAS, State-Trait Anxiety Inventory (State), and BDI-II. Multiple regressions were run to predict anxiety, depressive symptoms, behavioral approach, and executive dysfunction from MJ group status, past year alcohol use, gender, and MJ*gender interactions, controlling for cotinine and ecstasy.

Results

MJ group predicted increased depressive symptoms (p =.049). Decreased fun-seeking (p =.04), reward response (p =.01), and BAS total (p =.01) were predicted by MJ group. Gender predicted decreased reward responsiveness in females (p =.049) and decreased BIS in females (p =.03). Female marijuana users had increased anxiety symptoms (p =.04) and increased disinhibition (p =.04). Increased cotinine predicted increased drive (p =.046), reward responsiveness (p =.008) and BAS Total (p =.02). Apathy and Executive Dysfunction were not predicted by any measures. All results had small effect sizes.

Conclusions/Importance

Depressive symptoms were greater in MJ users, while behavioral approach was decreased. Cotinine levels predicted increased behavioral approach. Female MJ users also had greater anxiety and disinhibition. In sum, these findings suggest sub-clinical threshold deficits related to regular marijuana use that are indicative of a need to prevent marijuana use in adolescents and young adults.

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<![CDATA[Investigating the Role of Assessment Method on Reports of Déjà Vu and Tip-of-the-Tongue States during Standard Recognition Tests]]> https://www.researchpad.co/article/5989da07ab0ee8fa60b76127

Déjà vu and tip-of-the-tongue (TOT) are retrieval-related subjective experiences whose study relies on participant self-report. In four experiments (ns = 224, 273, 123 and 154), we explored the effect of questioning method on reported occurrence of déjà vu and TOT in experimental settings. All participants carried out a continuous recognition task, which was not expected to induce déjà vu or TOT, but were asked about their experiences of these subjective states. When presented with contemporary definitions, between 32% and 58% of participants nonetheless reported experiencing déjà vu or TOT. Changing the definition of déjà vu or asking participants to bring to mind a real-life instance of déjà vu or TOT before completing the recognition task had no impact on reporting rates. However, there was an indication that changing the method of requesting subjective reports impacted reporting of both experiences. More specifically, moving from the commonly used retrospective questioning (e.g. “Have you experienced déjà vu?) to free report instructions (e.g. “Indicate whenever you experience déjà vu.) reduced the total number of reported déjà vu and TOT occurrences. We suggest that research on subjective experiences should move toward free report assessments. Such a shift would potentially reduce the presence of false alarms in experimental work, thereby reducing the overestimation of subjective experiences prevalent in this area of research.

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<![CDATA[Improving posture-motor dual-task with a supraposture-focus strategy in young and elderly adults]]> https://www.researchpad.co/article/5989db51ab0ee8fa60bdc44b

In a postural-suprapostural task, appropriate prioritization is necessary to achieve task goals and maintain postural stability. A “posture-first” principle is typically favored by elderly people in order to secure stance stability, but this comes at the cost of reduced suprapostural performance. Using a postural-suprapostural task with a motor suprapostural goal, this study investigated differences between young and older adults in dual-task cost across varying task prioritization paradigms. Eighteen healthy young (mean age: 24.8 ± 5.2 years) and 18 older (mean age: 68.8 ± 3.7 years) adults executed a designated force-matching task from a stabilometer board using either a stabilometer stance (posture-focus strategy) or force-matching (supraposture-focus strategy) as the primary task. The dual-task effect (DTE: % change in dual-task condition; positive value: dual-task benefit, negative value: dual-task cost) of force-matching error and reaction time (RT), posture error, and approximate entropy (ApEn) of stabilometer movement were measured. When using the supraposture-focus strategy, young adults exhibited larger DTE values in each behavioral parameter than when using the posture-focus strategy. The older adults using the supraposture-focus strategy also attained larger DTE values for posture error, stabilometer movement ApEn, and force-matching error than when using the posture-focus strategy. These results suggest that the supraposture-focus strategy exerted an increased dual-task benefit for posture-motor dual-tasking in both healthy young and elderly adults. The present findings imply that the older adults should make use of the supraposture-focus strategy for fall prevention during dual-task execution.

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<![CDATA[Emotional Modulation of the Late Positive Potential during Picture Free Viewing in Older and Young Adults]]> https://www.researchpad.co/article/5989da01ab0ee8fa60b743c9

Hedonic bias during free viewing of novel emotional and neutral scenes was investigated in older adults and college students. A neurophysiological index of emotional picture processing–the amplitude of the centroparietal late positive potential (LPP)–was recorded from the scalp using a dense sensor array while participants (29 older adults; 21 college students) viewed emotionally engaging or mundane natural scenes that varied in specific content. Both students and older adults showed LPP enhancement when viewing affective, compared to neutral, scenes, and there was no difference in LPP amplitude between older individuals and college students when viewing neutral everyday scenes. However, compared to the college students, older individuals showed attenuated LPP amplitude when viewing emotional scenes, regardless of hedonic valence or specific content. Age related differences could be mediated by a reduction in reactive emotional arousal with age, possible mediated by repeated life exposure to emotional stimuli.

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