Index Of Impulsivity Research Articles

Variable Presence of an Evolutionarily New Brain Structure is Related to Trait Impulsivity

BackgroundImpulsivity is a multidimensional construct reflecting poor constraint over one’s behaviors. Clinical psychology research identifies separable impulsivity dimensions that are each unique transdiagnostic indicators for psychopathology. Yet, despite this apparent clinical importance, the shared and unique neuroanatomical correlates of these factors remain largely unknown. Concomitantly, neuroimaging research identifies variably present human brain structures implicated in cognition and disorder: the folds (sulci) of the cerebral cortex located in the latest developing and most evolutionarily expanded hominoid-specific association cortices. MethodsWe tethered these two fields to test whether variability in one such structure in anterior cingulate cortex (ACC)—the paracingulate sulcus (PCGS)—was related to individual differences in trait impulsivity. 120 adult participants with internalizing or externalizing psychopathology completed a magnetic resonance imaging scan and the Three-Factor Impulsivity Index. Using precision imaging techniques, we manually identified the PCGS, when present, and acquired quantitative folding metrics (PCGS length and ACC local gyrification index). ResultsNeuroanatomical-behavioral analyses revealed that participants with leftward or symmetrical PCGS patterns had greater severity of Lack of Follow Through (LFT)—which captures inattention and lack of perseverance—than those with rightward asymmetry. Neuroanatomical-functional analyses identified that the PCGS co-localized with a focal locus found in a neuroimaging meta-analysis on a feature underlying LFT. Both quantitative folding metrics did not relate to any impulsivity dimension. ConclusionsThis study advances understanding of the neuroanatomical correlates of impulsivity and establishes the notion that the topographical organization of distinct, hominoid-specific cortical expanses underlie separable impulsivity dimensions with robust, transdiagnostic implications for psychopathology.

Variable Presence of an Evolutionarily New Brain Structure is Related to Trait Impulsivity.

Impulsivity is a multidimensional construct reflecting poor constraint over one's behaviors. Clinical psychology research identifies separable impulsivity dimensions that are each unique transdiagnostic indicators for psychopathology. Yet, despite this apparent clinical importance, the shared and unique neuroanatomical correlates of these factors remain largely unknown. Concomitantly, neuroimaging research identifies variably present human brain structures implicated in cognition and disorder: the folds (sulci) of the cerebral cortex located in the latest developing and most evolutionarily expanded hominoid-specific association cortices. We tethered these two fields to test whether variability in one such structure in anterior cingulate cortex (ACC)-the paracingulate sulcus (PCGS)-was related to individual differences in trait impulsivity. 120 adult participants with internalizing or externalizing psychopathology completed a magnetic resonance imaging scan and the Three-Factor Impulsivity Index. Using precision imaging techniques, we manually identified the PCGS, when present, and acquired quantitative folding metrics (PCGS length and ACC local gyrification index). Neuroanatomical-behavioral analyses revealed that participants with leftward or symmetrical PCGS patterns had greater severity of Lack of Follow Through (LFT)-which captures inattention and lack of perseverance-than those with rightward asymmetry. Neuroanatomical-functional analyses identified that the PCGS co-localized with a focal locus found in a neuroimaging meta-analysis on a feature underlying LFT. Both quantitative folding metrics did not relate to any impulsivity dimension. This study advances understanding of the neuroanatomical correlates of impulsivity and establishes the notion that the topographical organization of distinct, hominoid-specific cortical expanses underlie separable impulsivity dimensions with robust, transdiagnostic implications for psychopathology.

Original article: adolescent dietary patterns derived using principal component analysis and neuropsychological functions: a cross-sectional analysis of Walnuts Smart Snack cohort.

A balanced diet is relevant for neuropsychological functioning. We aimed to analyze the association between dietary patterns and neuropsychological outcomes in a sample of healthy adolescents of the Walnuts Smart Snack (WSS) cohort from Barcelona city.We performed principal components analysis (PCA) to determine dietary patterns in the adolescent sample using a food frequency questionnaire (60 items). Multiple linear regression models were performed to analyze the association between PCA dietary patterns with neuropsychological outcomes: Strengths and Difficulties (SDQ) externalizing and internalizing scores, Attention Network Test (ANT) Impulsivity Index and Emotional Recognition Task (ERT) scores. We additionally adjusted the models for child sex, age, body mass index (BMI), physical activity and maternal education.Six dietary patterns were identified in PCA analyses. "low consumption of calorie-dense foods" dietary pattern had a negative association (protective) with the both SDQ outcomes (p value < 0.001) and "Nuts" dietary pattern showed a negative (protective) association with impulsivity index = -24.60, 95% CI = -36.80, -12.41, p value < 0.001).Overall, our main results suggest that healthy dietary patterns, including higher intakes of "nuts" and a preference of "low consumption of calorie-dense foods" dietary patterns, could provide a beneficial association with neuropsychological functions during the adolescence period. The associations may include improvements of externalizing and internalizing problem symptoms, and impulsivity.

The computational and neural substrates of individual differences in impulsivity under loss framework.

Numerous neuroimaging studies have identified significant individual variability in intertemporal choice, often attributed to three neural mechanisms: (1) increased reward circuit activity, (2) decreased cognitive control, and (3) prospection ability. These mechanisms that explain impulsivity, however, have been primarily studied in the gain domain. This study extends this investigation to the loss domain. We employed a hierarchical Bayesian drift-diffusion model (DDM) and the inter-subject representational similarity approach (IS-RSA) to investigate the potential computational neural substrates underlying impulsivity in loss domain across two experiments (n = 155). These experiments utilized a revised intertemporal task that independently manipulated the amounts of immediate and delayed-loss options. Behavioral results demonstrated positive correlations between the drift rate, measured by the DDM, and the impulsivity index K in Exp. 1 (n = 97) and were replicated in Exp. 2 (n = 58). Imaging analyses further revealed that the drift rate significantly mediated the relations between brain properties (e.g., prefrontal cortex activations and gray matter volume in the orbitofrontal cortex and precuneus) and K in Exp. 1. IS-RSA analyses indicated that variability in the drift rate also mediated the associations between inter-subject variations in activation patterns and individual differences in K. These findings suggest that individuals with similar impulsivity levels are likely to exhibit similar value processing patterns, providing a potential explanation for individual differences in impulsivity within a loss framework.

Neural indices of heritable impulsivity: Impact of the COMT Val158Met polymorphism on frontal beta power during early motor preparation

Studies of COMT Val158Met suggest that the neural circuitry subserving inhibitory control may be modulated by this functional polymorphism altering cortical dopamine availability, thus giving rise to heritable differences in behaviors. Using an anatomically-constrained magnetoencephalography method and stratifying the sample by COMT genotype, from a larger sample of 153 subjects, we examined the spatial and temporal dynamics of beta oscillations during motor execution and inhibition in 21 healthy Met158/Met158 (high dopamine) or 21 Val158/Val158 (low dopamine) genotype individuals during a Go/NoGo paradigm. While task performance was unaffected, Met158 homozygotes demonstrated an overall increase in beta power across regions essential for inhibitory control during early motor preparation (∼100 ms latency), suggestive of a global motor “pause” on behavior. This increase was especially evident on Go trials with slow response speed and was absent during inhibition failures. Such a pause could underlie the tendency of Met158 allele carriers to be more cautious and inhibited. In contrast, Val158 homozygotes exhibited a beta drop during early motor preparation, indicative of high response readiness. This decrease was associated with measures of behavioral disinhibition and consistent with greater extraversion and impulsivity observed in Val homozygotes. These results provide mechanistic insight into genetically-determined interindividual differences of inhibitory control with higher cortical dopamine associated with momentary response hesitation, and lower dopamine leading to motor impulsivity.

Choice impulsivity after repeated social stress is associated with increased perineuronal nets in the medial prefrontal cortex

Repeated stress can predispose to substance abuse. However, behavioral and neurobiological adaptations that link stress to substance abuse remain unclear. This study investigates whether intermittent social defeat (ISD), a stress protocol that promotes drug-seeking behavior, alters intertemporal decision-making and cortical inhibitory function in the medial prefrontal cortex (mPFC). Male long evans rats were trained in a delay discounting task (DDT) where rats make a choice between a fast (1 s) small reward (1 sugar pellet) and a large reward (3 sugar pellets) that comes with a time delay (10 s or 20 s). A decreased preference for delayed rewards was used as an index of choice impulsivity. Rats were exposed to ISD and tested in the DDT 24 h after each stress episode, and one- and two-weeks after the last stress episode. Immunohistochemistry was performed in rat’s brains to evaluate perineuronal nets (PNNs) and parvalbumin GABA interneurons (PV) labeling as markers of inhibitory function in mPFC. ISD significantly decreased the preference for delayed large rewards in low impulsive, but not high impulsive, animals. ISD also increased the density of PNNs in the mPFC. These results suggest that increased choice impulsivity and cortical inhibition predispose animals to seek out rewards after stress.

Gender differences in the pathway of childhood trauma, impulsivity and adult eating behaviour: a cross-sectional study

Objective: The current cross-sectional study aimed to examine the association between childhood trauma, impulsivity, binge eating symptoms, and body mass index (BMI) in a sample of males and females. We also aimed to investigate the indirect association of childhood trauma with binge eating through impulsivity while controlling for BMI. Method: Participants were 410 young adults (mean age = 20.9 years, range 18–24; female = 73.9%) who completed online measures of childhood trauma, impulsivity, binge eating symptoms, and self-reported height and weight. Mediation models were tested using multi-group structural equation modelling. Results: Childhood trauma and impulsivity were associated with an increased risk of binge eating symptoms in females but not males, corroborating previous studies. There was a significant difference in the binge eating symptoms index between sexes, but not regarding the index of childhood trauma and impulsivity. Additionally, adverse childhood experiences were associated with impulsivity and the association of childhood trauma with binge eating was mediated by impulsivity in the female sample. Conclusions: Our results suggest sex-dependent patterns and risk factors that may impact binge eating symptoms. The implications of our results suggest that impulsivity might be a vulnerability factor for binge eating, especially for females.

Fault diagnosis of air compressor set-up using decision tree based J48 classification algorithm

This paper describes an air compressor fault diagnosis method based on the acquisition of audio signals pertaining to seven faulty and one healthy condition. These audio signals are processed using Local Mean Decomposition (LMD) signal processing technique. Further, statistical indicators have been evaluated for feature extraction considering the decomposed signals. From different statistical indictors mean, variance, root mean square (RMS), root mean amplitude (RMA), absolute mean amplitude (AMA), kurtosis, peak to peak index, waveform index, peak index, impulse index, margin index, skewness, Shannon entropy, standard deviation, log energy entropy, log detector and CPT has been selected for decision tree based J48 classification algorithm. Decision tree based J48 classification algorithm more accurately identified healthy and faulty bearing state in an air compressor with the help of all statistical indicators. Data set consists of 360 instances having 17 attributes with 2 classes (healthy and bearing fault). Higher classification accuracy of J48 algorithm (96.66 %) has been obtained for healthy and faulty bearing conditions. LMD along with decision tree based J48 classification algorithm is quite suitable for processing and monitoring in situ fault features in air compressor set-up.

Different topological patterns in structural covariance networks between high and low delay discounters.

People prefer immediate over future rewards because they discount the latter's value (a phenomenon termed "delay discounting," used as an index of impulsivity). However, little is known about how the preferences are implemented in brain in terms of the coordinated pattern of large-scale structural brain networks. To examine this question, we classified high discounting group (HDG) and low discounting group (LDG) in young adults by assessing their propensity for intertemporal choice. We compared global and regional topological properties in gray matter volume-based structural covariance networks between two groups using graph theoretical analysis. HDG had less clustering coefficient and characteristic path length over the wide sparsity range than LDG, indicating low network segregation and high integration. In addition, the degree of small-worldness was more significant in HDG. Locally, HDG showed less betweenness centrality (BC) in the parahippocampal gyrus and amygdala than LDG. These findings suggest the involvement of structural covariance network topology on impulsive choice, measured by delay discounting, and extend our understanding of how impulsive choice is associated with brain morphological features.

Mentalizing in Adolescents and Young Adults with Attention Deficit Hyperactivity Disorder: Associations with Age and Attention Problems

Introduction: Growing, albeit heterogenous evidence questions whether attention deficit/hyperactivity disorder (ADHD) is associated with socio-cognitive impairments, especially beyond childhood. This study focuses on mentalizing – the socio-cognitive ability to attribute and reason in terms of mental states. We aimed to characterize mentalizing performance in terms of correct scores and types of errors in adolescents and young adults with ADHD. Methods: Forty-nine adolescents and adults with ADHD and 49 healthy controls matched for age and gender completed a computerized naturalistic mentalizing task, the Movie for Assessment of Social Cognition (MASC). Repeated measures analyses of variance examined the effects of age group and ADHD diagnosis on MASC performance. Additionally, associations between mentalizing scores, the severity of attention problems, and the presence of comorbidity were explored in the ADHD group. Results: Results showed an increased prevalence of hypomentalizing errors in adolescents with ADHD. Lower mentalizing scores in adolescents with ADHD were correlated with indices of inattentiveness, impulsivity, and vigilance problems. Hypomentalizing errors in adolescents showed to be particularly associated with inattentiveness, after controlling for age and comorbidity. In contrast, adults with ADHD performed similarly to controls and their scores on the mentalizing task were not correlated to attention problems. Conclusion: These findings highlight potential developmental differences in mentalizing abilities in ADHD youths and their association with attentional impairments.

Effect of real-world fear on risky decision-making in medical school-based students: A quasi-experimental study.

Objective: To explore the effect of real-world fear on risky decision-making under certainty and uncertainty. Methods: This quasi-experimental study enrolled non-psychology undergraduate volunteers aged between 17 and 20 years old from the Preventive Medical Institute medical school in Xi'an. Participants were randomly divided into two groups, and each group received a two-stage crossover design intervention (of a calm and fearful situation) and completed the tasks of risky decision-making under uncertainty (the balloon analog risk task: BART) and certainty (the Cambridge gambling task: CGT), respectively. The primary outcomes included the behavioral impulsivity measured by the BART value, and the speed of decision-making, the quality of decisions, the adventure index, behavioral impulsivity, and risk adjustment measured by CGT. The secondary outcome was the concentration of cortisol in the saliva. Results: A total of 60 questionnaires and data were obtained from 60 participants (28 males and 32 females, aged 19.55 ± 0.75). Compared with the calm situation, participants were more likely to have a lower BART value (p = 0.013), slower speed of decision-making (p < 0.05), and higher adventure index (p = 0.018) in the fearful situation. The quality of decisions (p = 0.189), behavioral impulsivity index (p = 0.182), and risk adjustment (p = 0.063) between subjects in the fearful and calm situations were comparable. Furthermore, the mean value of the adventure index of CGT in male subjects was significantly higher than that in female subjects (p < 0.05), and the cortisol concentration in saliva during the fearful situation was significantly higher compared to the calm situation (p < 0.05). Conclusion: Fear might reduce behavioral impulsivity under uncertainty, and increase the adventure index under certainty in risky decision-making. Risky behavior might be influenced by gender: under certainty in risky decision-making, men were more adventurous. Additionally, fear increased the secretion of cortisol in saliva.

Effect of Impulsive Noise on IRS-Aided Communication Systems

Recent studies have explored the potential benefits of the intelligent reflecting surface (IRS) in different wireless communication scenarios. However, no work has quantitatively analyzed the performance of IRS-aided communication systems impaired by non-Gaussian noise. In this article, motivated by this research gap, we study the effect of impulsive noise on IRS-aided communication systems. Specifically, the channel impairments are modeled by Middleton's class A noise (MCA) and Weibull fading. By leveraging the Laguerre series, accurate channel distributions are derived. Building upon these expressions, new closed-form expressions of average bit-error-rate (BER), average channel capacity (ACC), and outage probability (OP) are obtained. To gain further insight into the system performance at high signal-to-noise ratio (SNR) regime, the asymptotic expressions of BER, OP, and ACC are derived. In addition, a tight upper bound of ACC is obtained. The effect of the impulsive index <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><tex-math notation="LaTeX">$ (A)$</tex-math></inline-formula> on the systems performance metrics is investigated for different parameter settings. Moreover, it is shown that IRS-assisted communication systems outperforms a multi-hop relaying network impaired by impulsive noise. The results reveal that the system performance impaired by impulsive noise can be significantly improved by increasing the reflecting elements (REs). The derived expressions are in excellent agreement with Monte-Carlo simulations.

Red blood cell omega-3 fatty acids and attention scores in healthy adolescents

Omega-3 fatty acids are critical for brain function. Adolescence is increasingly believed to entail brain vulnerability to dietary intake. In contrast to the abundant research on the omega-3 docosahexaenoic acid (DHA) in cognition, research on DHA and attention in healthy adolescents is scarce. In addition, the role of alpha-linolenic acid (ALA), the vegetable omega-3 fatty acid, is unexplored. We examined associations between DHA and ALA and attention function among a healthy young population. In this cross-sectional study conducted in 372 adolescents (13.8 ± 0.9 years-old), we determined the red blood cell proportions of DHA and ALA by gas chromatography (objective biomarkers of their long-term dietary intake) and measured attention scores through the Attention Network Test. We constructed multivariable linear regression models to analyze associations, controlling for known confounders. Compared to participants at the lowest DHA tertile (reference), those at the highest DHA tertile showed significantly lower hit reaction time-standard error (higher attentiveness) (28.13 ms, 95% confidence interval [CI] = – 52.30; – 3.97), lower hit reaction time ( – 38.30 ms, 95% CI = – 73.28; – 3.33) and lower executive conflict response ( – 5.77 ms, 95% CI = – 11.44; – 0.09). In contrast, higher values were observed in those at the top tertile of ALA in hit reaction time compared to the lowest one (46.14 ms, 95% CI = 9.90; 82.34). However, a beneficial association was observed for ALA, with decreasing impulsivity index across tertiles. Overall, our results suggest that DHA (reflecting its dietary intake) is associated with attention performance in typically developing adolescents. The role of dietary ALA in attention is less clear, although higher blood levels of ALA appear to result in lower impulsivity. Future intervention studies are needed to determine the causality of these associations and to better shape dietary recommendations for brain health during the adolescence period.

Neuroanatomical Correlates of Emotion-Related Impulsivity

BackgroundEmotion-related impulsivity (ERI) refers to chronically poor self-control during periods of strong emotion. ERI robustly predicts psychiatric disorders and related problems, yet its neuroanatomical correlates are largely unknown. We tested whether local brain morphometry in targeted brain regions that integrate emotion and control could explain ERI severity. MethodsOne hundred twenty-two adults (ages 18–55 years) with internalizing or externalizing psychopathology completed a structural magnetic resonance imaging (MRI) scan, the Three-Factor Impulsivity Index, and the Structured Clinical Interview for DSM-5. The Three-Factor Impulsivity Index measures two types of ERI and a third type of impulsivity not linked to emotion. Cortical reconstruction yielded cortical thickness and local gyrification measurements. We evaluated whether morphometry in the orbitofrontal cortex (OFC), insula, amygdala, and nucleus accumbens was associated with ERI severity. Hypotheses and analyses were preregistered. ResultsLower cortical gyrification in the right lateral OFC was associated with high ERI severity in a full, preregistered model. Separate examinations of local gyrification and cortical thickness also showed a positive association between gyrification in the left lateral OFC and ERI. An integrated measure of hemispheric imbalance in lateral OFC gyrification (right < left) correlated with ERI severity. These findings were specific to ERI and did not appear with non–emotion-related impulsivity. ConclusionsLocal gyrification in the lateral OFC is associated with ERI severity. The current findings fit with existing theories of OFC function, strengthen the connections between the transdiagnostic literature in psychiatry and neuroscience, and may guide future treatment development.

Unraveling the Contribution of Serotonergic Polymorphisms, Prefrontal Alpha Asymmetry, and Individual Alpha Peak Frequency to the Emotion-Related Impulsivity Endophenotype

The unique contribution of the serotonin transporter-linked polymorphic region (5-HTTLPR), intronic region 2 (STin2), and monoamine oxidase A (MAO-A) genes to individual differences in personality traits has been widely explored, and research has shown that certain forms of these polymorphisms relate to impulsivity and impulsivity-related disorders. Humans showing these traits are also described as having an asymmetrical prefrontal cortical activity when compared to others. In this explorative study, we examine the relationship between serotonergic neurotransmission polymorphisms, cortical activity features (prefrontal alpha asymmetry, individual alpha peak frequency [iAPF]), emotion-related and non-emotion-related impulsivity in humans. 5-HTTLPR, MAO-A, and STin2 polymorphisms were assessed in blood taken from 91 participants with high emotion-related impulsivity levels. Sixty-seven participants completed resting electroencephalography and a more comprehensive impulsivity index. In univariate analyses, iAPF correlated with both forms of emotion-related impulsivity. In multiple linear regression models, 5-HTTLPR polymorphism (model 1, adj. R2 = 15.2%) and iAPF were significant interacting predictors of emotion-related impulsivity, explaining a large share of the results’ variance (model 2, adj. R2 = 21.2%). Carriers of the low transcriptional activity 5-HTTPLR and MAO-A phenotypes obtained higher emotion-related impulsivity scores than others did. No significant results were detected for non-emotion-related impulsivity or for a form of emotion-related impulsivity involving cognitive/motivational reactivity to emotion. Our findings support an endophenotypic approach to impulsivity, showing that tri-allelic 5-HTTLPR polymorphism, iAPF, and their interaction are relevant predictors of one form of emotion-related impulsivity.

Emotion-related impulsivity and rumination: Unique and conjoint effects on suicidal ideation, suicide attempts, and nonsuicidal self-injury across two samples.

Rumination and emotion-related impulsivity predict suicidal ideation, suicide attempts, and nonsuicidal self-injury (NSSI). Because rumination and emotion-related impulsivity, though, are highly correlated, we consider their unique vs. conjoint influence on suicidal ideation and self-harm. Across two samples of adults (N's=171 and 191), we examined how rumination and emotion-related impulsivity relate to suicidal ideation, suicide attempts, and NSSI. We assess the more general process of repetitive negative thinking and the more specific process of suicide-related rumination. Participants completed the Three-Factor Impulsivity Index and the self-report Columbia-Suicide Severity Rating Scale. Those in sample 1 completed the Perseverative Thinking Questionnaire and the Deliberate Self-Harm Inventory, and those in Sample 2 completed the Suicide Rumination Scale. Emotion-related impulsivity and both forms of rumination showed robust bivariate correlations with suicidal ideation, suicide attempts, and NSSI. Neither rumination or impulsivity related to suicide attempts controlling for ideation or to NSSI. In multivariable analyses, emotion-related impulsivity but not general rumination was tied to suicidal ideation. In contrast, suicide-related rumination was more directly tied to suicidal ideation than was impulsivity. Findings provide support for a more nuanced approach to the forms of impulsivity and rumination related to suicidal ideation.

A Developmental Perspective on Facets of Impulsivity and Brain Activity Correlates From Adolescence to Adulthood

BackgroundOn a theoretical level, impulsivity represents a multidimensional construct associated with acting without foresight, inefficient inhibitory response control, and alterations in reward processing. On an empirical level, relationships and changes in associations between different measures of impulsivity from adolescence into young adulthood and their relation to neural activity during inhibitory control and reward anticipation have not been fully understood. MethodsWe used data from IMAGEN, a longitudinal multicenter, population-based cohort study in which 2034 healthy adolescents were investigated at age 14, and 1383 were reassessed as young adults at age 19. We measured the construct of trait impulsivity using self-report questionnaires and neurocognitive indices of decisional impulsivity. With functional magnetic resonance imaging, we assessed brain activity during inhibition error processing using the stop signal task and during reward anticipation in the monetary incentive delay task. Correlations were analyzed, and mixed-effect models were fitted to explore developmental and predictive effects. ResultsAll self-report and neurocognitive measures of impulsivity proved to be correlated during adolescence and young adulthood. Further, pre-supplementary motor area and inferior frontal gyrus activity during inhibition error processing was associated with trait impulsivity in adolescence, whereas in young adulthood, a trend-level association with reward anticipation activity in the ventral striatum was found. For adult delay discounting, a trend-level predictive effect of adolescent neural activity during inhibition error processing emerged. ConclusionsOur findings help to inform theories of impulsivity about the development of its multidimensional nature and associated brain activity patterns and highlight the need for taking functional brain development into account when evaluating neuromarker candidates.

Can impulsivity evolve in response to childhood environmental harshness?

Previous studies have suggested that human impulsivity is an adaptive response to childhood environmental harshness: individuals from families of low socioeconomic status (SES) tend to be more impulsive. However, no studies have tested the evolvability of this reaction norm. This study examined whether (a) impulsivity is associated with higher fitness among individuals from low SES families, while (b) it is associated with lower fitness among individuals from high SES families. We assessed three indices of impulsivity (temporal discounting, risk taking and fast/slow life history strategy), childhood SES and five proxy indices of fitness (number of children, lifelong singlehood, annual household income, subjective SES and life satisfaction) of 692 middle-aged participants (40-45 years old). None of the results supported the evolvability of the impulsivity reaction norm, although low childhood SES was associated with lower fitness on every proxy measure. Impulsivity (operationalised as the fast life history strategy) was associated with lower fitness regardless of childhood SES.

Prevalências de dependência de internet e sua associação à impulsividade, agressividade, depressão e ansiedade em jovens universitários

Abstract The increasing availability of the Internet, although with many positive effects for most, has triggered addictive effects for part of the population. They experience social isolation due to Internet overuse and, when deprived of it, they feel anxiety, fissure, and psychomotor agitation. This study investigated associations among Internet addiction, demographic and cognitive variables, such as impulsivity, aggression, and depressive and/or anxiety symptoms. In this study, 1,485 young adults (67.9% women) were assessed using four psychological instruments. It was found that 19.1% of the participants presented a moderate or severe internet addiction, with men having a higher prevalence (45.0%). The risk population also included individuals who use the Internet for gaming and residents of the Northeastern region of Brazil. Moreover, a higher index of motor or attentional impulsivity, or more depressive symptoms, seems to increase the prevalence of Internet Addiction, requiring greater attention in preventive strategies.

Comparative Analysis of Morphological Indicators of Street Workout Athletes with Different Training Experience

Purpose. The purpose of the article is a comparative analysis of the morphological indicators of street workout (StW) athletes with different training experience (TE). &#x0D; Materials and methods. The study involved StW athletes (n = 27). Athletes were divided into two groups: StW-1 (n = 13, age 15.15 ± 0.44 years, TE 1.56 ± 0.22 years); StW-2 (n = 14, age 16.57 ± 0.48 years, TE 2.64 ± 0.53 years). The body length and body mass were measured; the level and harmony of physical development were evaluated. The regression method was used. The handgrip was evaluated by hand dynamometry indicators Camry EH101 electronic dynamometer (China). The handgrip was measured by the maximum grip frequency in 10 s the electronic device "Kepai" (China). The content of muscle and adipose tissue were determined by the body composition monitor OMRON BF-511 (Japan). &#x0D; Results. The average value of the strength index in the StW-1 was more than 60%, and in the StW-2 was more than 70%. The StW-2 had a significant excess of the hand dynamometry, power index, impulse index of both hands; index of static and dynamic grip of the left hand; specific weight of muscles. The average level of physical development was observed in (61.54 ± 13.49)%, above the average was observed in (23.08 ± 11.69)% of StW-1. Harmonious physical development had (38.46 ± 13.49)%. In StW-2, the average level of physical development had (64.29 ± 12.81)%, above the average had (21.43 ± 10.97)%. Harmonious physical development had (50.00 ± 13.36)%. In StW-1 (46.15 ± 13.83)% had a normal fat content and a fat level below normal. In StW-2, the normal fat content had (30.77 ± 12.80)%, and the low adipose tissue content was (69.23 ± 12.80)%. &#x0D; Conclusions. All athletes had a high content of muscle tissue. It was confirmed the specific effect of StW on the body of athletes. Grip strength, specific weight of muscle component are predictors of success. The information content of the proposed indices for monitoring the functional state of athletes was confirmed.