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The objective of this study was to investigate the effect of dietary fatty acid (FA) composition on bile acid (BA) metabolism in a pig model of NAFLD, by using a multiomics approach combined with histology and serum biochemistry. Thirty 20-day-old Iberian pigs pair-housed in pens were randomly assigned to receive 1 of 3 hypercaloric diets for 10 wk: 1) lard-enriched (LAR; n = 5 pens), 2) olive oil-enriched (OLI; n = 5), and 3) coconut oil-enriched (COC; n = 5). Animals were euthanized on week 10 after blood sampling, and liver, colon, and distal ileum (DI) were collected for histology, metabolomics, and transcriptomics. Data were analyzed by multivariate and univariate statistics. Compared with OLI and LAR, COC increased primary and secondary BAs in liver, plasma, and colon. In addition, both COC and OLI reduced circulating fibroblast growth factor 19, increased hepatic necrosis, composite lesion score, and liver enzymes in serum, and upregulated genes involved in hepatocyte proliferation and DNA repair. The severity of liver disease in COC and OLI pigs was associated with increased levels of phosphatidylcholines, medium-chain triacylglycerides, trimethylamine-N-oxide, and long-chain acylcarnitines in the liver, and the expression of profibrotic markers in DI, but not with changes in the composition or size of BA pool. In conclusion, our results indicate a role of dietary FAs in the regulation of BA metabolism and progression of NAFLD. Interventions that aim to modify the composition of dietary FAs, rather than to regulate BA metabolism or signaling, may be more effective in the treatment of NAFLD.NEW & NOTEWORTHY Bile acid homeostasis and signaling is disrupted in NAFLD and may play a central role in the development of the disease. However, there are no studies addressing the impact of diet on bile acid metabolism in patients with NAFLD. In juvenile Iberian pigs, we show that fatty acid composition in high-fat high-fructose diets affects BA levels in liver, plasma, and colon but these changes were not associated with the severity of the disease.
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Ácidos e Sais Biliares , Gorduras na Dieta , Fígado , Hepatopatia Gordurosa não Alcoólica , Animais , Dieta Hiperlipídica , Ácidos Graxos , Humanos , Modelos Animais , SuínosRESUMO
A link between diet and avian intestinal anatomy is generally assumed. We collated the length of intestinal sections and body mass of 390 bird species and tested relationships with diet, climate and locomotion. There was a strong phylogenetic signal in all datasets. The total and small intestine scaled more-than-geometrically (95%CI of the scaling exponent > 0.33). The traditional dietary classification (faunivore, omnivore and herbivore) had no significant effect on total intestine (TI) length. Significant dietary proxies included %folivory, %frugi-nectarivory and categories (frugi-nectarivory, granivory, folivory, omnivory, insectivory and vertivory). Individual intestinal sections were affected by different dietary proxies. The best model indicates that higher consumption of fruit and nectar, drier habitats, and a high degree of flightedness are linked to shorter TI length. Notably, the length of the avian intestine depends on other biological factors as much as on diet. Given the weak dietary signal in our datasets, the diet intestinal length relationships lend themselves to narratives of flexibility (morphology is not destiny) rather than of distinct adaptations that facilitate using one character (intestine length) as proxy for another (diet). Birds have TIs of about 85% that of similar-sized mammals, corroborating systematic differences in intestinal macroanatomy between vertebrate clades.
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Aves , Intestinos , Animais , Aves/anatomia & histologia , Dieta/veterinária , Ecossistema , Mamíferos , Filogenia , Especificidade da EspécieRESUMO
An often-stated ecomorphological assumption that has the status of 'textbook knowledge' is that the dimensions of the digestive tract correlate with diet, where herbivores-consuming diets of lower digestibility-have longer intestinal tracts than faunivores-consuming diets of higher digestibility. However, statistical approaches have so far failed to demonstrate this link. Here, we collated data on the length of intestinal sections and body mass of 519 mammal species, and test for various relationships with trophic, climatic and other biological characteristics. All models showed a strong phylogenetic signal. Scaling relationships with body mass showed positive allometry at exponents greater than 0.33, except for the caecum, which is particularly large in smaller species. Body mass was more tightly linked to small intestine than to large intestine length. Adding a diet proxy to the relationships increased model fit for all intestinal sections, except for the small intestine when accounting for phylogeny. Thus, the diet has a main effect on the components of the large intestine, with longer measures in herbivores. Additionally, measures of habitat aridity had a positive relationship with large intestine length. The small intestine was longer in species from colder habitats at higher latitudes, possibly facilitating the processing of peak intake rates during the growing season. This study corroborates intuitive expectations on digestive tract anatomy, while the dependence of significant results on large sample sizes and inclusion of specific taxonomic groups indicates that the relationships cannot be considered fixed biological laws.
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Intestinos , Mamíferos , Animais , Dieta , Digestão , Trato Gastrointestinal , FilogeniaRESUMO
BACKGROUND: Fructose consumption has been linked to nonalcoholic fatty liver disease (NAFLD) in children. However, the effect of high-fructose corn syrup (HFCS) compared with sucrose in pediatric NAFLD has not been investigated. OBJECTIVES: We tested whether the isocaloric substitution of dietary sucrose by HFCS would increase the severity of NAFLD in juvenile pigs, and whether this effect would be associated with changes in gut histology, SCFA production, and microbial diversity. METHODS: Iberian pigs, 53-d-old and pair-housed in pens balanced for weight and sex, were randomly assigned to receive a mash diet top-dressed with increasing amounts of sucrose (SUC; n = 3 pens; 281.6-486.8 g/kg diet) or HFCS (n = 4; 444.3-724.8 g/kg diet) during 16 wk. Diets exceeded the animal's energy requirements by providing sugars in excess, but met the requirements for all other nutrients. Animals were killed at 165 d of age after blood sampling, and liver, muscle, and gut were collected for histology, metabolome, and microbiome analyses. Data were analyzed by multivariate and univariate statistics. RESULTS: Compared with SUC, HFCS increased subcutaneous fat, triacylglycerides in plasma, and butyrate in colon (P ≤ 0.05). In addition, HFCS decreased UMP and short-chain acyl carnitines in liver, and urea nitrogen and creatinine in serum (P ≤ 0.05). Microbiome analysis showed a 24.8% average dissimilarity between HFCS and SUC associated with changes in SCFA-producing bacteria. Body weight gain, intramuscular fat, histological and serum markers of liver injury, and circulating hormones, glucose, and proinflammatory cytokines did not differ between diets. CONCLUSIONS: Fructose consumption derived from HFCS promoted butyrate synthesis, triglyceridemia, and subcutaneous lipid deposition in juvenile Iberian pigs, but did not increase serum and histological markers of NAFLD compared with a sucrose-enriched diet. Longer studies could be needed to observe differences in liver injury among sugar types.
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Adiposidade/efeitos dos fármacos , Sacarose Alimentar/efeitos adversos , Xarope de Milho Rico em Frutose/efeitos adversos , Hepatopatia Gordurosa não Alcoólica/etiologia , Triglicerídeos/sangue , Animais , Sacarose Alimentar/administração & dosagem , Ácidos Graxos Voláteis/metabolismo , Feminino , Microbioma Gastrointestinal , Trato Gastrointestinal/anatomia & histologia , Trato Gastrointestinal/efeitos dos fármacos , Xarope de Milho Rico em Frutose/administração & dosagem , Masculino , Distribuição Aleatória , SuínosRESUMO
To investigate the role of bile acids (BAs) in the pathogenesis of diet-induced nonalcoholic steatohepatitis (NASH), we fed a "Western-style diet" [high fructose, high fat (HFF)] enriched with fructose, cholesterol, and saturated fat for 10 wk to juvenile Iberian pigs. We also supplemented probiotics with in vitro BA deconjugating activity to evaluate their potential therapeutic effect in NASH. Liver lipid and function, cytokines, and hormones were analyzed using commercially available kits. Metabolites, BAs, and fatty acids were measured by liquid chromatography-mass spectrometry. Histology and gene and protein expression analyses were performed using standard protocols. HFF-fed pigs developed NASH, cholestasis, and impaired enterohepatic Farnesoid-X receptor (FXR)-fibroblast growth factor 19 (FGF19) signaling in the absence of obesity and insulin resistance. Choline depletion in HFF livers was associated with decreased lipoprotein and cholesterol in serum and an increase of choline-containing phospholipids in colon contents and trimethylamine-N-oxide in the liver. Additionally, gut dysbiosis and hyperplasia increased with the severity of NASH, and were correlated with increased colonic levels of choline metabolites and secondary BAs. Supplementation of probiotics in the HFF diet enhanced NASH, inhibited hepatic autophagy, increased excretion of taurine and choline, and decreased gut microbial diversity. In conclusion, dysregulation of BA homeostasis was associated with injury and choline depletion in the liver, as well as increased biliary secretion, gut metabolism and excretion of choline-based phospholipids. Choline depletion limited lipoprotein synthesis, resulting in hepatic steatosis, whereas secondary BAs and choline-containing phospholipids in colon may have promoted dysbiosis, hyperplasia, and trimethylamine synthesis, causing further damage to the liver.NEW & NOTEWORTHY Impaired Farnesoid-X receptor (FXR)-fibroblast growth factor 19 (FGF19) signaling and cholestasis has been described in nonalcoholic fatty liver disease (NAFLD) patients. However, therapeutic interventions with FXR agonists have produced contradictory results. In a swine model of pediatric nonalcoholic steatohepatitis (NASH), we show that the uncoupling of intestinal FXR-FGF19 signaling and a decrease in FGF19 levels are associated with a choline-deficient phenotype of NASH and increased choline excretion in the gut, with the subsequent dysbiosis, colonic hyperplasia, and accumulation of trimethylamine-N-oxide in the liver.
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Ácidos e Sais Biliares/metabolismo , Colina/metabolismo , Colo/metabolismo , Colo/microbiologia , Fatores de Crescimento de Fibroblastos/metabolismo , Microbioma Gastrointestinal , Fígado/metabolismo , Hepatopatia Gordurosa não Alcoólica/metabolismo , Receptores Citoplasmáticos e Nucleares/metabolismo , Fatores Etários , Animais , Colo/patologia , Modelos Animais de Doenças , Disbiose , Feminino , Hiperplasia , Fígado/patologia , Masculino , Hepatopatia Gordurosa não Alcoólica/microbiologia , Hepatopatia Gordurosa não Alcoólica/patologia , Hepatopatia Gordurosa não Alcoólica/prevenção & controle , Probióticos/administração & dosagem , Transdução de Sinais , Sus scrofaRESUMO
Few studies have focussed on the link between anxiety and inhibitory control in the absence of stimulus-driven external threat. This two-part experiment examined the interactions between (1) somatic trait anxiety, somatic situational stress (i.e. threat of electric shock), and effort, and (2) cognitive trait anxiety, cognitive situational stress (i.e. ego-threat instructions), and effort, on inhibitory processes using a Go-No-Go paradigm. Trait anxiety was operationalised using questionnaire scores and effort was operationalised using a visual analogue scale. Performance effectiveness was measured using the d' parameter from signal detection theory and processing efficiency was indexed by the ratio of d' to response time on correct trials. Results indicated that somatic trait anxiety and stress did not predict effectiveness or efficiency. Cognitive trait anxiety and stress were associated with both inhibitory effectiveness and efficiency deficits; however, contrary to expectations these deficits were evident at higher rather than lower mental effort. Results suggest a distinction between how somatic and cognitive anxiety manifest on tasks involving inhibitory control.
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Ansiedade , Cognição , Inibição Psicológica , Esforço Físico , Estresse Psicológico/psicologia , Adolescente , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Inventário de Personalidade , Tempo de Reação , Detecção de Sinal Psicológico , Adulto JovemRESUMO
The present study explored relationships between alexithymia-a trait characterized by difficulties identifying and describing feelings and an external thinking style-and negative moods, negative mood regulation expectancies, facial recognition of emotions, emotional empathy, and alcohol consumption. The sample consisted of 102 university (primarily psychology) students (13 men, 89 women) aged 18 to 50 years (M = 22.18 years). Participants completed the Toronto Alexithymia Scale (TAS-20), Negative Mood Regulation Scale (NMRS), Depression Anxiety Stress Scales (DASS-21), Reading the Mind in the Eyes Test (RMET), Interpersonal Reactivity Index (IRI), and Alcohol Use Disorders Identification Test (AUDIT). Results were consistent with previous findings of positive relationships of TAS-20 alexithymia scores with both alcohol use (AUDIT) and negative moods (DASS-21) and a negative relationship with emotional self-regulation as indexed by NMRS. Predicted negative associations of both overall TAS-20 alexithymia scores and the externally oriented thinking (EOT) subscale of the TAS-20 with both RMET facial recognition of emotions and the empathic concern (EC) subscale of the IRI were supported. The mood self-regulation index NMRS fully mediated the relationship between alexithymia and negative moods. Hierarchical linear regressions revealed that, after other relevant variables were controlled for, the EOT subscale of the TAS-20 predicted RMET and EC. The concrete thinking or EDT facet of alexithymia thus appears to be associated with diminished facial recognition of emotions and reduced emotional empathy. The negative moods associated with alexithymia appear to be linked to subjective difficulties in self-regulation of emotions.
Assuntos
Sintomas Afetivos/fisiopatologia , Consumo de Bebidas Alcoólicas/fisiopatologia , Emoções/fisiologia , Empatia/fisiologia , Expressão Facial , Reconhecimento Facial/fisiologia , Autocontrole , Pensamento/fisiologia , Adolescente , Adulto , Afeto/fisiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto JovemRESUMO
Indices of mood, mood regulation, and executive functioning were examined in 61 current smokers who have smoked daily for at least one year, 36 ex-smokers who had not smoked a cigarette for at least one year, and 86 never-smokers. All participants completed the following measures online: Depression Anxiety Stress Scales (DASS-21), the Negative Mood Regulation (NMR) scale, the Frontal Systems Behavior Scale (FrSBe), the Fagerström Test for Cigarette Dependence (FTCD), and the Alcohol Use Disorders Identification Test (AUDIT). Multivariate analysis of variance (MANOVA) followed by Tukey post-hoc tests revealed significant differences (p < .01) such that current smokers indicated worse functioning than both ex-smokers and never-smokers on DASS, NMR, and FrSBe, as well as heavier drinking as measured by AUDIT. These differences remained significant even after controlling for AUDIT scores. Results most plausibly reflect a return to pre-smoking baseline brain function in long-term abstinent ex-smokers.
Assuntos
Afeto , Lobo Frontal/fisiopatologia , Abandono do Hábito de Fumar/psicologia , Prevenção do Hábito de Fumar , Tabagismo/terapia , Adulto , Consumo de Bebidas Alcoólicas/fisiopatologia , Consumo de Bebidas Alcoólicas/psicologia , Função Executiva , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Testes Neuropsicológicos , Escalas de Graduação Psiquiátrica , Fumar/fisiopatologia , Fumar/psicologia , Controles Informais da Sociedade , Inquéritos e Questionários , Fatores de Tempo , Tabagismo/fisiopatologia , Tabagismo/psicologia , Adulto JovemRESUMO
Cancer survivors commonly contend with concurrent cognitive difficulties such as problems with attention and concentration, and psychological distress, including anxiety and depression. However, the associations between attentional and emotional difficulties within the specific context of melanoma survivors remain relatively unexplored. Premised on attentional control theory, the current study employed a cross-sectional design to explore the interplay among trait anxiety (dispositional) and situational anxiety (cancer-related worry), depression and attentional control (ability to inhibit distractors and flexibly shift within and between tasks) in a sample of 187 melanoma survivors aged 18 to 58 years (Mage = 36.83 years, SDage = 5.44 years; 93% female). Data were analyzed using a moderated multiple regression, with anxiety, cancer worry and depression as predictors, and attentional control as the criterion variable. After statistically controlling for the variance of chemotherapy, we found that individuals with higher trait anxiety and higher cancer-related worry reported greater attentional control at low levels of depression, yet poorer attentional control at high depression, relative to individuals with low anxiety. Our findings suggest that anxiety and depression are differentially related to attentional control in melanoma survivors. The results provide a marker for clinicians addressing anxiety and depression in this population. Implications for primary healthcare are discussed.
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Although relationships between intestinal morphology between trophic groups in reptiles are widely assumed and represent a cornerstone of ecomorphological narratives, few comparative approaches actually tested this hypothesis on a larger scale. We collected data on lengths of intestinal sections of 205 reptile species for which either body mass (BM), snout-vent-length (SVL) or carapax length (CL) was recorded, transforming SVL or CL into BM if the latter was not given, and analyzed scaling patterns with BM and SVL, accounting for phylogeny, comparing three trophic guilds (faunivores, omnivores, herbivores), and comparing with a mammal dataset. Length-BM relationships in reptiles were stronger for the small than the large intestine, suggesting that for the latter, additional factors might be relevant. Adding trophic level did not consistently improve model fit; only when controlling for phylogeny, models indicated a longer large intestine in herbivores, due to a corresponding pattern in lizards. Trophic level effects were highly susceptible to sample sizes, and not considered strong. Models that linked BM to intestine length had better support than models using SVL, due to the deviating body shape of snakes. At comparable BM, reptiles had shorter intestines than mammals. While the latter finding corresponds to findings of lower tissue masses for the digestive tract and other organs in reptiles as well as our understanding of differences in energetic requirements between the classes, they raise the hitherto unanswered question what it is that reptiles of similar BM have more than mammals. A lesser effect of trophic level on intestine lengths in reptiles compared to mammals may stem from lesser selective pressures on differentiation between trophic guilds, related to the generally lower food intake and different movement patterns of reptiles, which may not similarly escalate evolutionary arms races tuned to optimal agility as between mammalian predators and prey.
Assuntos
Intestinos/anatomia & histologia , Mamíferos/anatomia & histologia , Répteis/anatomia & histologia , Anatomia Comparada , Animais , Tamanho Corporal , Carnivoridade , Ingestão de Energia , Herbivoria , Intestino Grosso/anatomia & histologia , Intestino Delgado/anatomia & histologia , Mamíferos/classificação , Tamanho do Órgão , Répteis/classificaçãoRESUMO
Octodon degus are herbivorous rodents that are adapted anatomically and behaviorally to utilize a fibrous diet with moderate-to-low levels of nonstructural carbohydrate. Captive degus should consume foods containing nutrients comparable to those consumed by free-ranging animals. The species is highly social, demonstrating a broad array of communication methods that make them appealing as a companion animal species. Controlled research studies with degus have produced a wealth of information that facilitates the care of this species in captivity.
Assuntos
Fenômenos Fisiológicos da Nutrição Animal/fisiologia , Comportamento Animal/fisiologia , Fibras na Dieta/metabolismo , Necessidades Nutricionais , Octodon/fisiologia , Ração Animal , Criação de Animais Domésticos/normas , Animais , Animais Domésticos , Fibras na Dieta/administração & dosagem , Feminino , Masculino , Especificidade da EspécieRESUMO
Kinkajous are not suitable pets for most people, because the species takes considerable resources to accommodate their needs. They are often overlooked in zoo collections and in field research, because they are not considered threatened or endangered. The authors have presented an overview of the diets and enrichment methods that sustain reproduction, growth, and longevity in captive kinkajous. It is important, however, to recognize that kinkajous' nutritional needs are as poorly understood as almost everything else about their natural history.
Assuntos
Ração Animal/análise , Fenômenos Fisiológicos da Nutrição Animal/fisiologia , Dieta/veterinária , Necessidades Nutricionais , Procyonidae/fisiologia , Ração Animal/normas , Animais , Animais Domésticos , Animais Recém-Nascidos , Feminino , MasculinoRESUMO
Given the well-established associations of the personality traits alexithymia, impulsivity, and reward sensitivity with problematic use of a variety of substances, including alcohol and cannabis, the present study sought to determine whether daily tobacco smoking is similarly linked to these traits. Male and female adults aged 18 to 40 years were recruited from the local Australian community, allowing comparison of demographically similar samples of current daily smokers (n = 47) to never-smokers (n = 59) on the relevant self-report measures. Multivariate analysis of covariance revealed that current smokers scored significantly higher than never-smokers on indices of negative mood, impulsiveness, and risky alcohol use, after controlling for social desirability. No significant group differences were found on indices of alexithymia, reward sensitivity, or punishment sensitivity. Results suggest that chronic daily cigarette smoking may be an exception to the maladaptive behaviors associated with alexithymia, and is driven primarily by mood regulation and poor impulse control.
Assuntos
Afeto/fisiologia , Fumar Cigarros/psicologia , Comportamento Impulsivo , Fumantes/psicologia , Adolescente , Adulto , Sintomas Afetivos/epidemiologia , Consumo de Bebidas Alcoólicas/epidemiologia , Austrália , Fumar Cigarros/epidemiologia , Feminino , Humanos , Masculino , Análise Multivariada , Recompensa , Adulto JovemRESUMO
Research in semantic word list-learning paradigms suggests that presentation modality during encoding may influence word recognition at test. Given these findings, it is argued that some previous misinformation effect research might contain methodologies which are problematic. Misleading information groups typically receive erroneous information in written narratives, which may be further impeded by written tests. Results may therefore be explained by misinformation or encoding specificity. In two experiments, participants received restated, neutral, and misleading post-event information through auditory or written modalities. Participants' recognition and recall of critical details about the source event were tested. In a recognition test using the standard testing procedure, there were no condition differences for post-event information presented via an auditory modality. However, for post-event information presented in the text modality, recognition performance was more accurate for restated information relative to neutral information, which in-turn was better than the misled condition. Using the modified testing procedure, the differences were again limited to the text condition. Better performance was evident in the restated condition relative to the average of the neutral and the misled conditions, and there was no difference in performance between the neutral and the misled conditions. Using a recall test, however, there was no effect of modality. Memory was significantly better for restated information than for the average of the neutral and the misled conditions and poorer in the misled condition relative to the neutral condition. Results are discussed in terms of the effects of contextual cues at test, and methodological and interpretational limitations associated with previous research.
Assuntos
Sinais (Psicologia) , Memória/fisiologia , Rememoração Mental/fisiologia , Comunicação Persuasiva , Reconhecimento Psicológico/fisiologia , Adulto , Feminino , Humanos , Masculino , Narração , Estudantes/psicologia , Sugestão , Comportamento Verbal/fisiologia , Gravação de VideoteipeRESUMO
Attentional control theory (ACT) describes the mechanisms associated with the relationship between anxiety and cognitive performance. We investigated the relationship between cognitive trait anxiety, situational stress and mental effort on phonological performance using a simple (forward-) and complex (backward-) word span task. Ninety undergraduate students participated in the study. Predictor variables were cognitive trait anxiety, indexed using questionnaire scores; situational stress, manipulated using ego threat instructions; and perceived level of mental effort, measured using a visual analogue scale. Criterion variables (a) performance effectiveness (accuracy) and (b) processing efficiency (accuracy divided by response time) were analyzed in separate multiple moderated-regression analyses. The results revealed (a) no relationship between the predictors and performance effectiveness, and (b) a significant 3-way interaction on processing efficiency for both the simple and complex tasks, such that at higher effort, trait anxiety and situational stress did not predict processing efficiency, whereas at lower effort, higher trait anxiety was associated with lower efficiency at high situational stress, but not at low situational stress. Our results were in full support of the assumptions of ACT and implications for future research are discussed. (PsycINFO Database Record
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Ansiedade/psicologia , Atenção/fisiologia , Memória de Curto Prazo/fisiologia , Estresse Psicológico/psicologia , Adulto , Feminino , Humanos , Masculino , Adulto JovemRESUMO
The present study sought to determine whether certain personality traits associated with problematic substance use may also characterize young adults who report problematic internet use. An index of internet addiction as well as measures of traits previously linked to problematic substance use were administered to a sample of 86 young adults aged 18-30 years. Measures included the Internet Addiction Test (IAT), Sensitivity to Punishment and Sensitivity to Reward Questionnaire (SPSRQ), Depression Anxiety and Stress Scales (DASS-21), Toronto Alexithymia Scale (TAS-20), and the Fear of Intimacy Scale (FIS). Results indicated that IAT scores were significantly positively correlated with TAS-20, DASS-21, SPSRQ and FIS scores, as predicted. When age, gender and negative mood were controlled in a hierarchical regression, sensitivity to punishment (SP), sensitivity to reward (SR) and FIS significantly contributed to variance in IAT in the final model. SP partially mediated the relationship between TAS-20 and IAT, whereas no such mediation was indicated for SR or FIS. Present findings suggest that alexithymia and reward sensitivity may be important risk factors for internet addiction as for problematic substance use, whereas sensitivity to punishment may account for at least part of the association between alexithymia and problematic use of the internet.
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Attentional control theory (ACT) predicts that trait anxiety and situational stress interact to impair performance on tasks that involve attentional shifting. The theory suggests that anxious individuals recruit additional effort to prevent shortfalls in performance effectiveness (accuracy), with deficits becoming evident in processing efficiency (the relationship between accuracy and time taken to perform the task). These assumptions, however, have not been systematically tested. The relationship between cognitive trait anxiety, situational stress, and mental effort in a shifting task (Wisconsin Card Sorting Task) was investigated in 90 participants. Cognitive trait anxiety was operationalized using questionnaire scores, situational stress was manipulated through ego threat instructions, and mental effort was measured using a visual analogue scale. Dependent variables were performance effectiveness (an inverse proportion of perseverative errors) and processing efficiency (an inverse proportion of perseverative errors divided by response time on perseverative error trials). The predictors were not associated with performance effectiveness; however, we observed a significant 3-way interaction on processing efficiency. At higher mental effort (+1 SD), higher cognitive trait anxiety was associated with poorer efficiency independently of situational stress, whereas at lower effort (-1 SD), this relationship was highly significant and most pronounced for those in the high-stress condition. These results are important because they provide the first systematic test of the relationship between trait anxiety, situational stress, and mental effort on shifting performance. The data are also consistent with the notion that effort moderates the relationship between anxiety and shifting efficiency, but not effectiveness.
Assuntos
Ansiedade/psicologia , Atenção/fisiologia , Cognição/fisiologia , Eficiência/fisiologia , Modelos Psicológicos , Estresse Psicológico , Pensamento/fisiologia , Adolescente , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Testes Neuropsicológicos , Tempo de Reação , Adulto JovemRESUMO
INTRODUCTION: Acute alcohol intoxication has been found to increase perseverative errors on the Wisconsin Card Sorting Test, a well known neuropsychological index of prefrontal cortical functioning, in both laboratory and naturalistic settings. METHOD: The present study examined the relationship between levels of alcohol consumption at campus drinking venues and performance of the Iowa Gambling Task (IGT), another neuropsychological test designed to assess prefrontal cortex dysfunction, after controlling for potential confounding variables including habitual alcohol intake (as a proxy for alcohol tolerance), trait impulsivity, and everyday executive functioning. RESULTS: The 49 participants of both genders aged 18 to 30years were recruited at the relevant venues and showed a broad range of blood alcohol concentrations (BACs) from virtually zero (.002%) to .19%. After controlling for demographic variables, habitual use of alcohol and illicit drugs, and frontal lobe related behavioural traits including impulsivity and disinhibition, BAC negatively predicted gambling money won on the last two trial blocks of the IGT. CONCLUSIONS: Trait impulsivity and habitual alcohol use were also significant predictors. Results are discussed in terms of acute effects of alcohol on brain systems and the behavioural consequences of such effects on decision making.
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Intoxicação Alcoólica/fisiopatologia , Tomada de Decisões/efeitos dos fármacos , Tolerância a Medicamentos , Jogo de Azar/fisiopatologia , Comportamento Impulsivo , Testes Neuropsicológicos/estatística & dados numéricos , Adolescente , Adulto , Intoxicação Alcoólica/sangue , Sinais (Psicologia) , Feminino , Jogo de Azar/sangue , Jogo de Azar/economia , Humanos , Masculino , Adulto JovemRESUMO
BACKGROUND AND OBJECTIVES: Attentional Control Theory (ACT) predicts that trait anxiety and situation stress combine to reduce performance efficiency on tasks requiring rapid shifts in attention. Recent evidence has also suggested that working memory capacity (WMC) might moderate this relationship. We controlled for methodological difficulties in the existing literature to investigate the relationships between trait anxiety, situational stress, and WMC on attentional shifting. DESIGN AND METHOD: Seventy undergraduate students participated in the study. Trait anxiety was operationalized using questionnaire scores, situational stress was manipulated through a pressured counting task, and WMC was based on performance on the Automated Operation Span Task (AOSPAN). The shifting task involved a modified version of the Sternberg paradigm as the primary task and an oddball tone-discrimination task as the secondary task. Dependent variables were performance effectiveness (accuracy) and processing efficiency (accuracy divided by response time) on the secondary task. RESULTS: There was no effect of anxiety, stress, or WMC in predicting performance effectiveness; however, a significant three-way interaction on processing efficiency was observed. At higher WMC, anxiety and situational stress were not associated with processing efficiency. Conversely, at lower WMC, higher trait anxiety was associated with poorer efficiency but only for those who reported higher situational stress; for those who reported lower situational stress higher trait anxiety predicted facilitated efficiency. CONCLUSIONS: Results are interpreted with respect to ACT and directions for future research are discussed.
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Ansiedade/psicologia , Atenção , Memória de Curto Prazo , Estresse Psicológico/psicologia , Adolescente , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Resolução de Problemas , Inquéritos e Questionários , Adulto JovemRESUMO
The present study examined a widely used self-report index of trait impulsiveness in relation to performance on a well-known neuropsychological executive function test in 70 university undergraduate students (50 women, 20 men) aged 18 to 24 years old. Participants completed the Barratt Impulsiveness Scale (BIS-11) and the Frontal Systems Behavior Scale (FrSBe), after which they performed the Tower Test of the Delis-Kaplan Executive Function System. Hierarchical linear regression showed that after controlling for gender, current alcohol consumption, age at onset of weekly alcohol use, and FrSBe scores, BIS-11 significantly predicted Tower Test Achievement scores, ß = -.44, p < .01. The results indicate that self-reported impulsiveness is associated with poorer executive cognitive performance even in a sample likely to be characterized by relatively high general cognitive functioning (i.e., university students). The results also support the role of inhibition as a key aspect of executive task performance. Elevated scores on the BIS-11 and FrSBe are known to be linked to risky drinking in young adults as confirmed in this sample; however, only BIS-11 predicted Tower Test performance.