Sample Of Healthy Young Adults Research Articles

Lessons Learned from a Preliminary Study of Non-Treadmill-Based Trip Training

Falls are the leading cause of non-fatal injuries, and trips account for a high percentage of falls. Trip training is a form of perturbation-based balance training that involves exposing individuals to trip-like treadmill perturbations to improve reactive balance and thus reduce fall risk. However, significant costs and space requirements associated with specialized treadmills for this training may hinder its adoption. In this preliminary study, we evaluated a novel non-treadmill training (NT) protocol that would alleviate these requirements. We compared NT to the more common treadmill training (TT) and a control intervention among a convenience sample of healthy young adults. Results showed some promise for NT, while also providing valuable lessons for an upcoming similar study involving adults aged 65 and older.

Anger, Fear, and Sadness: Relations to Socioeconomic Status and the Amygdala.

Here, we test three often proposed hypotheses about socioeconomic status (SES), affect, and the brain, for which evidence is mixed or lacking. The first hypothesis, that negative affect is more common at lower levels of SES, has ample evidence from studies of psychiatric symptoms but is tested for the first time here across multiple measures of negative emotions in healthy young adults. The second hypothesis is actually a set of hypotheses, that SES is associated with three structural and functional properties of the amygdala. Third, and most important for the affective neuroscience of SES, is the hypothesis that SES differences in the amygdala are responsible for the affective differences. Despite the intuitive appeal of this hypothesis, it has rarely been tested and has never been confirmed. Here, we review the literature for evidence on each of these hypotheses and find in a number of cases that the evidence is weak or nonexistant. We then subject each hypothesis to a new empirical test with a large sample of healthy young adults. We confirm that negative affect is more common at lower levels of SES and we find a positive relation between SES and amygdala volume. However, evidence is weak on the relation of SES to functional properties of amygdala. Finally, the tendency toward negative affect in lower SES individuals cannot be accounted for by the structural or functional characteristics of the amygdala measured here.

Same same, but different: A psychometric examination of three frequently used experimental tasks for cognitive bias assessment in a sample of healthy young adults

Cognitive bias research draws upon the notion that altered information processing is key for understanding psychological functioning and well-being. However, little attention has been paid to the question of whether the frequently used experimental paradigms hold adequate psychometric properties. The present study examined the psychometric properties of three widely used cognitive bias tasks: the Approach-Avoidance Task (AAT), the visual dot-probe-task, and the Implicit Association Test (IAT). Approach, attentional, and association biases towards valenced stimuli were repeatedly measured at five different time points in a sample of 79 healthy young adults. Two different devices were used for assessment: a personal computer (PC) and a touchscreen-based tablet. Reliability estimates included internal consistency and temporal stability. Validity was inferred from convergence across different behavioral tasks and correlations between bias scores and self-reported psychological traits. Reliability ranged widely amongst tasks, assessment devices, and measurement time points. While the dot-probe-task appeared to be completely unreliable, bias scores obtained from the PC-based version of the AAT and both (PC and touchscreen) versions of the IAT showed moderate reliability. Almost no associations were found across information processing tasks or between implicit and explicit measures. Cognitive bias research should adopt a standard practice to routinely estimate and report psychometric properties of experimental paradigms, investigate feasible ways to develop more reliable tools, and use tasks that are suitable to answer the precise research question asked.

Wrist pressure and angulation during keyboarding: Comparison between two common wrist supports.

Wrist pressure and angulation while working at a computer workstation have been associated with cumulative trauma disorders (CTDs) like carpal tunnel syndrome (CTS). This quantitative, comparative study analyzed wrist pressure and angulation between two common wrist supports while typing at a standardized computer workstation. A convenience sample of healthy young adults completed a five-minute typing task at a standardized workstation with no wrist support, with the ErgoBeads™ wrist support, and with an Elzo™ (memory foam) wrist support. Pressure mapping (Tekscan™)) and goniometry were used as quantitative measures to examine wrist pressure and wrist angulation during the typing task; descriptive and inferential statistics were performed to compare wrist angulation and wrist pressure between two supports. For the sample (n = 54), both wrist supports demonstrated a significant (p < 0.001) reduction in wrist extension as well as pressure compared to typing at the workstation with no support. There was no statistically significant difference in peak or mean pressure between the ErgoBeads™ and Elzo™ wrist supports (p = 0.99). Significant difference was identified ((p < 0.001) for wrist angle as participants exhibited less wrist extension using the ErgoBeads™ (x¯=12.56∘; SD = 3.32°) support as compared to the Elzo™ (x¯=19.25∘; SD = 3.77°) support. The results suggest that the ErgoBeads™ and Elzo™ memory foam wrist supports are effective for reducing pressure between the wrist and work surface while the ErgoBeads™ support may promote a more neutral angle of the wrist while typing.

Reliability of quantitative multiparameter maps is high for magnetization transfer and proton density but attenuated for R1 and R2* in healthy young adults

We investigate the reliability of individual differences of four quantities measured by magnetic resonance imaging‐based multiparameter mapping (MPM): magnetization transfer saturation (MT), proton density (PD), longitudinal relaxation rate (R1), and effective transverse relaxation rate (R2*). Four MPM datasets, two on each of two consecutive days, were acquired in healthy young adults. On Day 1, no repositioning occurred and on Day 2, participants were repositioned between MPM datasets. Using intraclass correlation effect decomposition (ICED), we assessed the contributions of session‐specific, day‐specific, and residual sources of measurement error. For whole‐brain gray and white matter, all four MPM parameters showed high reproducibility and high reliability, as indexed by the coefficient of variation (CoV) and the intraclass correlation (ICC). However, MT, PD, R1, and R2* differed markedly in the extent to which reliability varied across brain regions. MT and PD showed high reliability in almost all regions. In contrast, R1 and R2* showed low reliability in some regions outside the basal ganglia, such that the sum of the measurement error estimates in our structural equation model was higher than estimates of between‐person differences. In addition, in this sample of healthy young adults, the four MPM parameters showed very little variability over four measurements but differed in how well they could assess between‐person differences. We conclude that R1 and R2* might carry only limited person‐specific information in some regions of the brain in healthy young adults, and, by implication, might be of restricted utility for studying associations to between‐person differences in behavior in those regions.

Suprathreshold Auditory Measures for Detecting Early-Stage Noise-Induced Hearing Loss in Young Adults.

Over 1 billion young adults are at risk for developing noise-induced hearing loss (NIHL) due to their habit of listening to music at loud levels. The gold standard for detecting NIHL is the audiometric notch around 3,000 to 6,000 Hz observed in pure tone audiogram. However, recent studies suggested that suprathreshold auditory measures might be more sensitive to detect early-stage NIHL in young adults. The present study compared suprathreshold measures in individuals with high and low noise exposure backgrounds (NEBs). We hypothesized that individuals with high NEB would exhibit reduced performance on suprathreshold measures than those with low NEB. An initial sample of 100 English-speaking healthy adults (18-35 years; females = 70) was obtained from five university classes. We identified 15 participants with the lowest NEB scores (10 females) and 15 participants with the highest NEB scores (10 females). We selected a sample of healthy young adults with no history of middle ear infection, and those in the low NEB group were selected with no history of impulse noise exposure. The study included conventional audiometry, extended high-frequency audiometry, middle ear muscle reflex (MEMR) thresholds, distortion-product otoacoustic emissions (DPOAEs), QuickSIN, and suprathreshold auditory brainstem response (ABR) measures. We used independent sample t-tests, correlation coefficients, and linear mixed model analysis to compare the audiometric measures between the NEB groups. The prevalence of audiometric notch was low in the study sample, even for individuals with high NEB. We found that: (1) individuals with high NEB revealed significantly reduced QuickSIN performance than those with low NEB; (2) music exposure via earphone revealed a significant association with QuickSIN; (3) individuals with high NEB revealed significantly reduced DPOAEs and ABR wave I amplitude compared with individuals with low NEB; (4) MEMR and ABR latency measures showed a modest association with NEB; and (5) audiometric thresholds across the frequency range did not show statistically significant association with NEB. Our results suggest that young adults with high NEB might exhibit impaired peripheral neural coding deficits leading to reduced speech-in-noise (SIN) performance despite clinically normal hearing thresholds. SIN measures might be more sensitive than audiometric notch for detecting early-stage NIHL in young adults.

The Resting-State Neural Network of Delay Discounting.

Delay discounting is a common phenomenon in daily life, which refers to the subjective value of a future reward decreasing as a function of time. Previous studies have identified several cortical regions involved in delay discounting, but the neural network constructed by the cortical regions of delay discounting is less clear. In this study, we employed resting-state functional magnetic resonance imaging (RS-fMRI) to measure the spontaneous neural activity in a large sample of healthy young adults and used the Monetary Choice Questionnaire to directly measure participants’ level of delay discounting. To identify the neural network of delay discounting at rest, we used an individual difference approach to explore brain regions whose spontaneous activities were related to delay discounting across the whole brain. Then, these brain regions served as seeds to identify the neural network of delay discounting. We found that the fractional amplitude of low-frequency fluctuations (fALFF) of the left insula were positively correlated to delay discounting. More importantly, its connectivity to the anterior cingulate cortex was read out for participants’ behavioral performance in the task of delay discounting. In short, our study provides empirical evidence that insula-anterior cingulate cortex connectivity may serve as a part of the neural network for delay discounting.

Intra-rater reliability of goniometry to measure scapular protraction and retraction

Study DesignObservational, descriptive design. BackgroundDespite scapular mobility being essential for the completion of activities of daily living (ADLs), there is currently no established, a reliable goniometric technique to measure scapular protraction and retraction. A proposed method has shown clinically significant inter-rater reliability for a goniometric technique for these measurements. PurposeThis observational descriptive study examined the intra-rater reliability of a goniometric technique to assess scapular protraction and retraction among a sample of healthy adults. MethodsAn occupational therapist who is a certified hand therapist (CHT) and an occupational therapy student used goniometry to measure the neutral (resting), protracted, and retracted positions of the right and left scapula for a sample of healthy young adults (n = 54; a total of 108 data points for each measurement). These measurements were compared to analyze intra-rater and inter-rater reliability. ResultsFor measurements of the scapula in neutral, protraction, and retraction, the standard error of measure (SEM) for repeat measures by the expert and novice raters was < 4.5° and < 3.9° respectively and ICC values ranged from poor to moderate (0.37-0.63). The SEM for measures between evaluators was < 5.0° and the ICC was poor (0.16-0.35). Minimum detectable change (MDC) values as a percentage of the mean (% MDC) ranged between 15.9 and 43.7% for intra-rater reliability and 21.9-52.8% for inter-rater reliability. DiscussionThe results of the study were mixed; variance of less than 5° for repeat measures by the same rater and measures between raters suggest clinically acceptable reliability. However, variance as a proportion of available motion (%MDC) demonstrates a broader range both above and below the threshold of 30% suggested for rehabilitation assessments. ConclusionThere are few efficient, reliable techniques to measure scapular mobility in clinical practice. The absolute reliability of goniometry to measure scapular protraction and retraction is similar to measurements of other joints. However, additional research and possible refinement of the technique is recommended to further address relative reliability and validity.

Frontostriatal functional connectivity underlies self-enhancement during social evaluation.

Self-enhancement, the tendency to view oneself positively, is a pervasive social motive widely investigated in the psychological sciences. Relatively little is known about the neurocognitive mechanisms underlying this motive, specifically in social-evaluative situations. To investigate whether positive emotion regulation circuitry, circuitry involved in modulating positive affect, relates to the self-enhancement motive in social contexts, we conducted an functional magnetic resonance imaging (fMRI) study in a healthy young adult sample. We hypothesized that self-enhancement indices (state and trait self-esteem) would relate to greater functional connectivity between right ventrolateral prefrontal cortex (RVLPFC), a region implicated in emotion regulation, and the ventral striatum (VS), a region associated with reward-related affect, during a social feedback task. Following social evaluation, participants experienced stable or decreased state self-esteem. Results showed that stable state self-esteem from pre- to post-scan and higher trait self-esteem related to greater RVLPFC–VS connectivity during positive evaluation. Stable-state self-esteem also related to greater RVLPFC–VS connectivity during negative evaluation. Moreover, RVLPFC activation during all types of feedback processing and left VS activation during negative feedback processing was greater for participants with stable-state self-esteem. These findings implicate neurocognitive mechanisms underlying emotion regulation in the self-enhancement motive and highlight a pathway through which self-enhancement may restore feelings of self-worth during threatening situations.

Brain structures and activity during a working memory task associated with internet addiction tendency in young adults: A large sample study.

The structural and functional brain characteristics associated with the excessive use of the internet have attracted substantial research attention in the past decade. In current study, we used voxel-based morphometry (VBM) and multiple regression analysis to assess the relationship between internet addiction tendency (IAT) score and regional gray and white matter volumes (rGMVs and rWMVs) and brain activity during a WM task in a large sample of healthy young adults (n = 1,154, mean age, 20.71 ± 1.78 years). We found a significant positive correlation between IAT score and gray matter volume (GMV) of right supramarginal gyrus (rSMG) and significant negative correlations with white matter volume (WMV) of right temporal lobe (sub-gyral and superior temporal gyrus), right sublobar area (extra-nuclear and lentiform nucleus), right cerebellar anterior lobe, cerebellar tonsil, right frontal lobe (inferior frontal gyrus and sub-gyral areas), and the pons. Also, IAT was significantly and positively correlated with brain activity in the default-mode network (DMN), medial frontal gyrus, medial part of the superior frontal gyrus, and anterior cingulate cortex during a 2-back working memory (WM) task. Moreover, whole-brain analyses of rGMV showed significant effects of interaction between sex and the IAT scores in the area spreading around the left anterior insula and left lentiform. This interaction was moderated by positive correlation in women. These results indicate that IAT is associated with (a) increased GMV in rSMG, which is involved in phonological processing, (b) decreased WMV in areas of frontal, sublobar, and temporal lobes, which are involved in response inhibition, and (c) reduced task-induced deactivation of the DMN, indicative of altered attentional allocation.

The Association between Body Mass Index and Intra-Cortical Myelin: Findings from the Human Connectome Project.

Intra-cortical myelin is a myelinated part of the cerebral cortex that is responsible for the spread and synchronization of neuronal activity in the cortex. Recent animal studies have established a link between obesity and impaired oligodendrocyte maturation vis-à-vis cells that produce and maintain myelin; however, the association between obesity and intra-cortical myelination remains to be established. To investigate the effects of obesity on intra-cortical myelin in living humans, we employed a large, demographically well-characterized sample of healthy young adults drawn from the Human Connectome Project (n = 1066). Intra-cortical myelin was assessed using a novel T1-w/T2-w ratio method. Linear regression analysis was used to investigate the association between body mass index (BMI), an indicator of obesity, and intra-cortical myelination, adjusting for covariates of no interest. We observed BMI was related to lower intra-cortical myelination in regions previously identified to be involved in reward processing (i.e., medial orbitofrontal cortex, rostral anterior cingulate cortex), attention (i.e., visual cortex, inferior/middle temporal gyrus), and salience detection (i.e., insula, supramarginal gyrus) in response to viewing food cues (corrected p < 0.05). In addition, higher BMIs were associated with more intra-cortical myelination in regions associated with somatosensory processing (i.e., the somatosensory network) and inhibitory control (i.e., lateral inferior frontal gyrus, frontal pole). These findings were also replicated after controlling for key potential confounding factors including total intracranial volume, substance use, and fluid intelligence. Findings suggested that altered intra-cortical myelination may represent a novel microstructure-level substrate underlying prior abnormal obesity-related brain neural activity, and lays a foundation for future investigations designed to evaluate how living habits, such as dietary habit and physical activity, affect intra-cortical myelination.

Early auditory cortical processing predicts auditory speech in noise identification and lipreading

Individuals typically exhibit better cross-sensory perception following unisensory loss, demonstrating improved perception of information available from the remaining senses and increased cross-sensory use of neural resources. Even individuals with no sensory loss will exhibit such changes in cross-sensory processing following temporary sensory deprivation, suggesting that the brain's capacity for recruiting cross-sensory sources to compensate for degraded unisensory input is a general characteristic of the perceptual process. Many studies have investigated how auditory and visual neural structures respond to within- and cross-sensory input. However, little attention has been given to how general auditory and visual neural processing relates to within and cross-sensory perception. The current investigation examines the extent to which individual differences in general auditory neural processing accounts for variability in auditory, visual, and audiovisual speech perception in a sample of young healthy adults. Auditory neural processing was assessed using a simple click stimulus. We found that individuals with a smaller P1 peak amplitude in their auditory-evoked potential (AEP) had more difficulty identifying speech sounds in difficult listening conditions, but were better lipreaders. The results suggest that individual differences in the auditory neural processing of healthy adults can account for variability in the perception of information available from the auditory and visual modalities, similar to the cross-sensory perceptual compensation observed in individuals with sensory loss.

Smartphone-based evaluation of awake bruxism behaviours in a sample of healthy young adults: findings from two University centres.

A smartphone‐based ecological momentary assessment (EMA) strategy was used to assess the frequency of awake bruxism behaviours, based on the report of five oral conditions (ie relaxed jaw muscles, teeth contact, mandible bracing, teeth clenching and teeth grinding). One hundred and fifty‐three (N = 153) healthy young adults (mean ± SD age = 22.9 ± 3.2 years), recruited in two different Italian Universities, used a dedicated smartphone application that sent 20 alerts/day at random times for seven days. Upon alert receipt, the subjects had to report in real‐time one of the above five possible oral conditions. Individual data were used to calculate an average frequency of the study population for each day. For each condition, a coefficient of variation (CV) of frequency data was calculated as the ratio between SD and mean values over the seven recording days. Average frequency of the different behaviours over the seven days was as follows: relaxed jaw muscle, 76.4%; teeth contact, 13.6%; mandible bracing, 7.0%; teeth clenching, 2.5%; and teeth grinding, 0.5%. No significant differences were found in frequency data between the two University samples. The relaxed jaw muscles condition was more frequent in males (80.7 ± 17.7) than in females (73.4 ± 22.2). The frequency of relaxed jaw muscles condition over the period of observation had a very low coefficient of variation (0.27), while for the different awake bruxism behaviours, CV was in a range between 1.5 (teeth contact) and 4.3 (teeth grinding). Teeth contact was the most prevalent behaviour (57.5–69.7). Findings from this investigation suggest that the average frequency of AB behaviours over one week, investigated using EMA‐approach, is around 23.6%.

Segregation, integration, and balance of large-scale resting brain networks configure different cognitive abilities

Diverse cognitive processes set different demands on locally segregated and globally integrated brain activity. However, it remains an open question how resting brains configure their functional organization to balance the demands on network segregation and integration to best serve cognition. Here we use an eigenmode-based approach to identify hierarchical modules in functional brain networks and quantify the functional balance between network segregation and integration. In a large sample of healthy young adults (n = 991), we combine the whole-brain resting state functional magnetic resonance imaging (fMRI) data with a mean-filed model on the structural network derived from diffusion tensor imaging and demonstrate that resting brain networks are on average close to a balanced state. This state allows for a balanced time dwelling at segregated and integrated configurations and highly flexible switching between them. Furthermore, we employ structural equation modeling to estimate general and domain-specific cognitive phenotypes from nine tasks and demonstrate that network segregation, integration, and their balance in resting brains predict individual differences in diverse cognitive phenotypes. More specifically, stronger integration is associated with better general cognitive ability, stronger segregation fosters crystallized intelligence and processing speed, and an individual's tendency toward balance supports better memory. Our findings provide a comprehensive and deep understanding of the brain's functioning principles in supporting diverse functional demands and cognitive abilities and advance modern network neuroscience theories of human cognition.

Macular Thickness Profile and Its Association With Best-Corrected Visual Acuity in Healthy Young Adults.

PurposeTo describe the thickness profiles of the full retinal and outer retinal layers (ORL) at the macula in healthy young adults, and associations with best-corrected visual acuity (BCVA).MethodsIn total, 1604 participants (19–30 years) underwent an eye examination that included measurements of their BCVA, axial length, and autorefraction. The retinal thickness at the foveal pit and at the nine Early Treatment of Diabetic Retinopathy Study macular regions (0.5-mm radius around the fovea, and superior, inferior, temporal, and nasal quadrants of the inner and outer rings of the macula) were obtained using spectral-domain optical coherence tomography imaging. A custom program was used to correct for transverse magnification effects because of different axial lengths.ResultsThe median full retinal and ORL thicknesses at the central macula were 285 µm and 92 µm. The full retina was thinnest centrally and thickest at the inner macula ring, whereas the ORL was thickest centrally and gradually decreased in thickness with increasing eccentricity. There was no association between axial length and the full retinal or ORL thickness. Increased thicknesses of the full retina at the central macula was associated with better BCVA; however, the effect size was small and not clinically significant.ConclusionsThis article mapped the full retinal and ORL thickness profile in a population-based sample of young healthy adults.Translational RelevanceThickness values presented in this article could be used as a normative reference for future studies on young adults and in clinical practice.

Are nutrition and physical activity associated with gut microbiota? A pilot study on a sample of healthy young adults.

The literature shows that gut microbiota composition is related with health, and a lot of individual and outer factors may determine its variability. In particular, nutrition and exercise seem to influence the presence in the gut of the two major bacterial phyla of Firmicutes and Bacteroidetes. An ongoing cross-sectional investigation is aimed to explore these associations in humans. Healthy Caucasian young adults were asked to provide a fecal sample in order to analyze their gut microbiome considering their Body Mass Index (BMI), adherence to Mediterranean diet and Physical Activity (PA) level. A total of 59 participants (49.1% males, mean age 23.1 ± 3.14 years) were enrolled so far. Firmicutes (61.6±14.6) and Bacteroidetes (30.7 ± 13.3) showed the highest relative abundance in fecal samples. The Pearson's analysis showed a significant negative correlation between PA and Firmicutes (r =-0.270, p = 0.03). Linear regression confirmed a significant decrease of this phylum with the increase of PA (R2 = 0.07, p = 0.03). These preliminary results suggest the association between physical activity and gut microbiota composition in healthy humans.

0177 Measuring Sleep Health Across Survey, Actigraphy, and Diary Methods in Young Adults

Abstract Introduction Sleep health is a relatively new construct including multiple dimensions of nighttime and daytime sleep across the 24-hour day. To date, few studies have investigated sleep health across various types of sleep measures. We collected sleep health data using survey, actigraphy, and daily diary, affording the unique ability to compare the latent factor structure of the sleep health construct across methods in a single sample of healthy young adults. Methods Undergraduates (N=540; 50% female; 71% white; mean age=18) self-reported sleep health via the 6-item RUSATED survey (Buysse, 2014), which queries “typical” sleep patterns including: daytime alertness and nocturnal sleep regularity, satisfaction, timing, efficiency, and duration (0=rarely/never to 2=usually/always); total score=0–12 (higher=better sleep health). A subsample (N=114) provided 7-day actigraphy and daily diaries, which were used to derive weeklong averages of the aforementioned sleep dimensions. Confirmatory factor analysis was conducted to assess model fit of three factors (survey, actigraphy, diary), each including within-method indicators of the six sleep dimensions; note the actigraphy model included diary satisfaction. Acceptable model fit was assessed using established criteria (e.g., Bentler, 1990): RMSEA &amp;lt; .08, CFI &amp;gt; .90, and TLI &amp;gt; .90. Maximum likelihood estimation was used. Results Average RUSATED total score was 7.1 (SD=2.5). Average actigraphy [diary] sleep dimensions were: Alertness (i.e., proportion of days napped)=21% [25%]; Duration=6.2hr [7.1hr]; Timing (i.e., midpoint)=5:00am [3:30am]; Regularity (i.e., SD of midpoint)=56 min [40 min]; Efficiency= 82% [95%]; Satisfaction=“average” to “good”. The survey model demonstrated acceptable fit (RMSEA [90%CI] = .06 [.03, .09], CFI=.96, TLI=.92) after correlating regularity and timing, as suggested by modification indices; factor loadings [λ(SE)] ranged from .27(.05) for efficiency to .71(.04) for satisfaction. Fit was poor for the diary model, whereas the actigraphy model failed to converge. Conclusion Sleep health models demonstrated adequate fit using survey but not actigraphy or diary data. The lack of acceptable fit for the latter may reflect differences in the measurement timeframe (e.g., “typical” sleep vs. 7-day averages) or the smaller sample size for the actigraphy/diary measures. Determining how to best measure sleep health and ultimately apply it to health-relevant outcomes is a valuable research agenda. Support T32HL07560; T32MH018269

Serum MMP‐3 and its Association with Large Artery Stiffness

Large artery stiffness is an independent predictor of cardiovascular disease (CVD) and all‐cause mortality. Stiffening of the large arteries (e.g., the aorta) is characterized by a marked reduction in the elastin‐collagen ratio in the extracellular matrix (ECM) of the arterial wall, and is largely the result of fatigue and fragmentation of ECM components due to cyclic stress. Matrix metalloproteinases (MMPs), a family of zinc‐dependent endopeptidases, may be important in the progression of arterial stiffness due to their involvement in ECM homeostasis and arterial wall remodeling. MMP‐3 may be of particular importance in arterial wall remodeling due to its ability to degrade numerous constituents of the arterial ECM, such as elastin and collagen. Previous studies have examined the effects of MMP‐3 genotype and expression on arterial wall stiffness in different disease populations; however, none have examined the association between MMP‐3 expression and large artery stiffness in a population of healthy young adults. Thus, the purpose of this study was to examine the association between serum MMP‐3 and carotid‐femoral pulse wave velocity (cfPWV), a non‐invasive measure of large artery stiffness, in a sample of healthy young adults. It is expected that individuals with higher serum MMP‐3 levels will present with larger cfPWVs. 156 participants (n = 68 males) aged 20–25 years were recruited as part of the Niagara Longitudinal Heart Study (NLHS), and all participants were free of any clinically diagnosed CVD. cfPWV (m/s) was determined using applanation tonometry as a non‐invasive surrogate of large artery stiffness. Serum MMP‐3 concentrations (pg/mL) were measured using standard ELISA techniques. Linear regression analyses were used to investigate the cross‐sectional association between serum MMP‐3 and cfPWV. Analyses were adjusted for age, sex, mean arterial pressure (MAP), body mass index (BMI), and smoking status. Data on cfPWV and MMP‐3 were available on 139 participants (n = 63 males), and were subsequently used in analysis. After adjustment for age, sex, MAP, BMI, and smoking status, serum MMP‐3 was significantly and positively associated with cfPWV (p = 0.038). cfPWV was also significantly and positively associated with MAP and smoking status (both p &lt; 0.001), but not age (p = 0.336). The association between cfPWV and both sex and BMI showed a positive trend, but only reached borderline significance (p = 0.059 and p = 0.054, respectively). Together, MAP, smoking status and serum MMP‐3 predicted 22% of the variation in cfPWV (adjusted R2 = 0.220, p &lt; 0.001). These data suggest that greater serum MMP‐3 levels are associated with larger cfPWVs and thus, greater large artery stiffness. Physiologic MMP‐3 levels function to maintain ECM homeostasis; however, greater MMP‐3 levels may exacerbate ECM degradation and contribute to stiffening of the large arteries. Future research should examine the potential functional role of MMP‐3 in CVD progression.Support or Funding InformationThe NLHS is funded by the Canadian Institute of Health Research (CIHR #363774 and #399332). KSD is funded by CIHR Doctoral Research Award—Frederick Banting and Charles Best Canada Graduate scholarship (RFN #167014). ARRM is supported by the Ontario Graduate Scholarship program

The relationship between subjective sleep quality and cognitive performance in healthy young adults: Evidence from three empirical studies

The role of subjective sleep quality in cognitive performance has gained increasing attention in recent decades. In this paper, our aim was to test the relationship between subjective sleep quality and a wide range of cognitive functions in a healthy young adult sample combined across three studies. Sleep quality was assessed by the Pittsburgh Sleep Quality Index, the Athens Insomnia Scale, and a sleep diary to capture general subjective sleep quality, and the Groningen Sleep Quality Scale to capture prior night’s sleep quality. Within cognitive functions, we tested working memory, executive functions, and several sub-processes of procedural learning. To provide more reliable results, we included robust frequentist as well as Bayesian statistical analyses. Unequivocally across all analyses, we showed that there is no association between subjective sleep quality and cognitive performance in the domains of working memory, executive functions and procedural learning in healthy young adults. Our paper can contribute to a deeper understanding of subjective sleep quality and its measures, and we discuss various factors that may affect whether associations can be observed between subjective sleep quality and cognitive performance.

Identification of Tendency to Alcohol Misuse From the Structural Brain Networks.

The propensity to engage in risky behaviors including excessive alcohol consumption may impose increased medical, emotional, and psychosocial burdens. Personality and behavioral traits of individuals may contribute in part to the involvement in risky behaviors, and therefore the classification of one’s traits may help identify those who are at risk for future onset of the addictive disorder and related behavioral issues such as alcohol misuse. Personality and behavioral characteristics including impulsivity, anger, reward sensitivity, and avoidance were assessed in a large sample of healthy young adults (n = 475). Participants also underwent diffusion tensor imaging for the analysis of structural brain networks. A data-driven clustering using personality and behavioral traits of the participants identified four subtypes. As compared with individuals clustered into the neutral type, individuals with a high level of impulsivity (A subtype) and those with high levels of reward sensitivity, impulsivity, anger, and avoidance (B subtype) showed significant associations with problem drinking. In contrast, individuals with high levels of impulsivity, anger, and avoidance but not reward sensitivity (C subtype) showed a pattern of social drinking that was similar to those of the neutral subtype. Furthermore, logistic regression analysis with ridge estimators was applied to demonstrate the neurobiological relevance for the identified subtypes according to distinct patterns of structural brain connectivity within the addiction circuitry [neutral vs. A subtype, the area under the receiver operator characteristic curve (AUC) = 0.74, 95% CI = 0.67–0.81; neutral vs. B subtype, AUC = 0.74, 95% CI = 0.66–0.82; neutral vs. C subtype, AUC = 0.77, 95% CI = 0.70–0.84]. The current findings enable the characterization of individuals according to subtypes based on personality and behavioral traits that are also corroborated by neuroimaging data and may provide a platform to better predict individual risks for addictive disorders.