Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 137
Filtrar
1.
Nutrients ; 16(5)2024 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-38474866

RESUMO

The neural mechanisms underlying susceptibility to eating more in response to large portions (i.e., the portion size effect) remain unclear. Thus, the present study examined how neural responses to portion size relate to changes in weight and energy consumed as portions increase. Associations were examined across brain regions traditionally implicated in appetite control (i.e., an appetitive network) as well as the cerebellum, which has recently been implicated in appetite-related processes. Children without obesity (i.e., BMI-for-age-and-sex percentile < 90; N = 63; 55% female) viewed images of larger and smaller portions of food during fMRI and, in separate sessions, ate four meals that varied in portion size. Individual-level linear and quadratic associations between intake (kcal, grams) and portion size (i.e., portion size slopes) were estimated. The response to portion size in cerebellar lobules IV-VI was associated with the quadratic portion size slope estimated from gram intake; a greater response to images depicting smaller compared to larger portions was associated with steeper increases in intake with increasing portion sizes. Within the appetitive network, neural responses were not associated with portion size slopes. A decreased cerebellar response to larger amounts of food may increase children's susceptibility to overeating when excessively large portions are served.


Assuntos
Sinais (Psicologia) , Tamanho da Porção , Criança , Humanos , Feminino , Masculino , Ingestão de Energia , Comportamento Alimentar/fisiologia , Refeições , Cerebelo
2.
Appetite ; 196: 107289, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38423300

RESUMO

Larger portions of food elicit greater intake than smaller portions of food, particularly when foods are high in energy density (kcal/g; ED). The neural mechanisms underlying this effect remain unclear. The present study used fMRI to assess brain activation to food (higher-ED, lower-ED) and non-food (office supplies) images presented in larger and smaller (i.e., age-appropriate) amounts in 61, 7-8-year-olds (29 male, 32 female) without obesity. Larger amounts of food increased activation in bilateral visual and right parahippocampal areas compared to smaller amounts; greater activation to food amount (larger > smaller) in this cluster was associated with smaller increases in food intake as portions increased. Activation to amount (larger > smaller) was stronger for food than office supplies in primary and secondary visual areas, but, for office supplies only, extended into bilateral parahippocampus, inferior parietal cortex, and additional visual areas (e.g., V7). Activation was greater for higher-vs. lower-ED food images in ventromedial prefrontal cortex for both larger and smaller amounts of food; however, this activation extended into left lateral orbital frontal cortex for smaller amounts only. Activation to food cues did not differ by familial risk for obesity. These results highlight potentially distinct neural pathways for encoding food energy content and quantity.


Assuntos
Encéfalo , Sinais (Psicologia) , Humanos , Masculino , Feminino , Encéfalo/diagnóstico por imagem , Encéfalo/fisiologia , Alimentos , Obesidade , Córtex Pré-Frontal/diagnóstico por imagem , Córtex Pré-Frontal/fisiologia , Imageamento por Ressonância Magnética
3.
JAMA Psychiatry ; 81(4): 414-425, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38324323

RESUMO

Importance: In the last 25 years, functional magnetic resonance imaging drug cue reactivity (FDCR) studies have characterized some core aspects in the neurobiology of drug addiction. However, no FDCR-derived biomarkers have been approved for treatment development or clinical adoption. Traversing this translational gap requires a systematic assessment of the FDCR literature evidence, its heterogeneity, and an evaluation of possible clinical uses of FDCR-derived biomarkers. Objective: To summarize the state of the field of FDCR, assess their potential for biomarker development, and outline a clear process for biomarker qualification to guide future research and validation efforts. Evidence Review: The PubMed and Medline databases were searched for every original FDCR investigation published from database inception until December 2022. Collected data covered study design, participant characteristics, FDCR task design, and whether each study provided evidence that might potentially help develop susceptibility, diagnostic, response, prognostic, predictive, or severity biomarkers for 1 or more addictive disorders. Findings: There were 415 FDCR studies published between 1998 and 2022. Most focused on nicotine (122 [29.6%]), alcohol (120 [29.2%]), or cocaine (46 [11.1%]), and most used visual cues (354 [85.3%]). Together, these studies recruited 19 311 participants, including 13 812 individuals with past or current substance use disorders. Most studies could potentially support biomarker development, including diagnostic (143 [32.7%]), treatment response (141 [32.3%]), severity (84 [19.2%]), prognostic (30 [6.9%]), predictive (25 [5.7%]), monitoring (12 [2.7%]), and susceptibility (2 [0.5%]) biomarkers. A total of 155 interventional studies used FDCR, mostly to investigate pharmacological (67 [43.2%]) or cognitive/behavioral (51 [32.9%]) interventions; 141 studies used FDCR as a response measure, of which 125 (88.7%) reported significant interventional FDCR alterations; and 25 studies used FDCR as an intervention outcome predictor, with 24 (96%) finding significant associations between FDCR markers and treatment outcomes. Conclusions and Relevance: Based on this systematic review and the proposed biomarker development framework, there is a pathway for the development and regulatory qualification of FDCR-based biomarkers of addiction and recovery. Further validation could support the use of FDCR-derived measures, potentially accelerating treatment development and improving diagnostic, prognostic, and predictive clinical judgments.


Assuntos
Comportamento Aditivo , Transtornos Relacionados ao Uso de Substâncias , Humanos , Imageamento por Ressonância Magnética , Sinais (Psicologia) , Transtornos Relacionados ao Uso de Substâncias/diagnóstico por imagem , Biomarcadores
4.
Obesity (Silver Spring) ; 31(12): 2998-3007, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37794530

RESUMO

OBJECTIVE: The objective of this study was to determine whether children with healthy weight who vary by familial risk for obesity differ in executive functioning. METHODS: Children (age 7-8 years) without obesity (n = 93, 52% male) who differed by familial risk for obesity (based on maternal weight status) completed go/no-go and stop-signal tasks to assess inhibitory control and an N-back task to assess working memory. Dual energy x-ray absorptiometry measured adiposity. Linear and mixed-effect models assessed unique effects and relative importance analysis-quantified relative effects of familial risk and percent body fat. RESULTS: Children at high compared with low familial risk showed worse inhibitory control; however, child adiposity was not associated with inhibitory control. Both high familial risk and greater child adiposity were associated with worse N-back performance when cognitive demand was high (2-back), but not low (0- and 1-back). The relative effect of familial risk on executive functioning was 2.7 to 16 times greater than the relative effect of percent body fat. CONCLUSIONS: These findings provide initial evidence that deficits in executive functioning may precede the development of obesity in children at high familial risk for this disease. Additional family risk studies are needed to elucidate the pathways through which maternal obesity influences child executive functioning and risk for obesity.


Assuntos
Obesidade Infantil , Gravidez , Humanos , Masculino , Criança , Feminino , Obesidade Infantil/complicações , Obesidade Infantil/genética , Predisposição Genética para Doença , Função Executiva , Adiposidade , Aumento de Peso
5.
Appetite ; 186: 106569, 2023 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-37059397

RESUMO

Deficits in executive functions (EFs), a set of cognitive processes related to self-regulation, are associated with the development of obesity. Prior studies from our group showed that lower food-cue related activation in brain regions implicated in self-regulation was related to a larger portion size effect. We tested the hypothesis that lower EFs in children would be positively related to the portion size effect. Healthy weight children aged 7-8 y (n = 88), who varied by maternal obesity status, participated in a prospective study. At baseline, the parent primarily in charge of feeding completed the Behavior Rating Inventory of Executive Function (BRIEF2) to assess child EFs, including Behavioral (BRI), Emotional (ERI), and Cognitive (CRI) indices. At 4 baseline sessions, children consumed meals in which the portion sizes of foods (pasta, chicken nuggets, broccoli, and grapes) varied by visit (total meal weight of 769, 1011, 1256, or 1492g). Intake increased with increasing portions in a linear trajectory (p < 0.001). EFs moderated the portion size effect such that lower BRI (p = 0.003) and ERI (p = 0.006) were associated with steeper increases in intake as portions increased. As amount of food increased, children in the lowest functioning tertiles for BRI and ERI increased intake by 35% and 36%, respectively, compared to children in the higher tertiles. Increases in intake among children with lower EFs were for higher- but not lower-energy-dense foods. Thus, in healthy weight children who varied by obesity risk, lower parentally reported EFs were associated with a larger portion size effect, and these results were independent of child and parent weight status. Therefore, EFs may be target behaviors that could be strengthened to help children moderate excess intake in response to large portions of energy-dense foods.


Assuntos
Ingestão de Energia , Tamanho da Porção , Gravidez , Criança , Humanos , Feminino , Tamanho da Porção/psicologia , Função Executiva , Estudos Prospectivos , Obesidade , Refeições
6.
Cogn Affect Behav Neurosci ; 23(2): 440-456, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36788202

RESUMO

Although the use of nondrug rewards (e.g., money) to facilitate smoking cessation is widespread, recent research has found that such rewards may be least effective when people who smoke cigarettes are tempted to do so. Specifically, among people who smoke, the neural response to nondrug rewards appears blunted when access to cigarettes is anticipated, and this blunting is linked to a decrease in willingness to refrain from smoking to earn a monetary incentive. Accordingly, methods to enhance the value of nondrug rewards may be theoretically and clinically important. The current proof-of-concept study tested if real-time fMRI neurofeedback training augments the ability to upregulate responses in reward-related brain areas relative to a no-feedback control condition in people who smoke. Adults (n = 44, age range = 20-44) who reported smoking >5 cigarettes per day completed the study. Those in the intervention group (n = 22, 5 females) were trained to upregulate brain responses using feedback of ongoing striatal activity (i.e., a dynamic "thermometer" that reflected ongoing changes of fMRI signal intensity in the striatum) in a single neurofeedback session with three training runs. The control group (n = 22, 5 females) underwent a nearly identical procedure but received no neurofeedback. Those who received neurofeedback training demonstrated significantly greater increases in striatal BOLD activation while attempting to think about something rewarding compared to controls, but this effect was present only during the first training run. Future neurofeedback research with those who smoke should explore how to make neurofeedback training more effective for the self-regulation of reward-related brain activities.


Assuntos
Encéfalo , Imageamento por Ressonância Magnética , Adulto , Feminino , Humanos , Adulto Jovem , Imageamento por Ressonância Magnética/métodos , Encéfalo/diagnóstico por imagem , Encéfalo/fisiologia , Recompensa , Mapeamento Encefálico/métodos , Fumar
7.
Psychol Assess ; 35(4): 311-324, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36656726

RESUMO

Interpersonal theory organizes social behavior along dominant (vs. submissive) and warm (vs. cold) dimensions. There is a growing interest in assessing these behaviors in naturalistic settings to maximize ecological validity and to study dynamic social processes. Studies that have assessed interpersonal behavior in daily life have primarily relied on behavioral checklists. Although checklists have advantages, they are discrepant with techniques used to capture constructs typically assessed alongside warmth and dominance, such as affect, which typically rely on adjective descriptors. Further, these checklists are distinct from the methodologies used at the dispositional level, such as personality inventories, which rarely rely on behavioral checklists. The present study evaluates the psychometric performance of interpersonal adjectives presented on a visual analog scale in five different samples. Validity of the Visual Interpersonal Analog scale (VIAS) approach to momentary assessment was evaluated by comparing its performance with an interpersonal behavior checklist and by examining associations among the VIAS Warmth and Dominance scales and other momentary and dispositional constructs. Results were generally consistent with an existing interpersonal behavior checklist at the within-person level but diverged somewhat at the dispositional level. Across the five samples, the VIAS generally performed as hypothesized at both the within- and between-person levels. (PsycInfo Database Record (c) 2023 APA, all rights reserved).


Assuntos
Relações Interpessoais , Comportamento Social , Humanos , Psicometria , Escala Visual Analógica , Personalidade
8.
Drug Alcohol Depend ; 243: 109717, 2023 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-36542962

RESUMO

BACKGROUND: Very light daily smoking (1-5 cigarettes/day) is associated with adverse consequences and is prevalent among young adults. Evidence suggests that perceived smoking opportunity modulates links between affect and craving in adults with heavier smoking patterns (e.g., > 10 cigarettes per day), but there is a lack of similar data in young adults with very light daily smoking patterns. This study addresses this gap by investigating the associations between affect and craving as a function of perceived smoking opportunity under naturalistic conditions. METHODS: Forty-one young adults aged 18-25 (M=21.03, SD=1.75) who reported smoking 1-5 cigarettes per day (M=3.2, SD=1.2) completed intermittent ratings of momentary affective valence and arousal, smoking craving, and perceived smoking opportunity on smartphones five times per day for seven days. RESULTS: Multilevel analyses suggested that when participants felt more pleasant or unpleasant, they were likely to report more intense craving. When smoking opportunity was perceived as high, affective arousal was positively associated with craving; this association was not observed when opportunity to smoke was perceived as low. CONCLUSIONS: These findings indicate that higher momentary intensity of affective valence (both negative and positive) is linked to stronger momentary craving in young adults who report very light daily smoking. Anticipating an opportunity to satisfy craving by smoking may strengthen the association between reported affective arousal and craving in this population. These results highlight the potential benefits of coping with craving (e.g., by regulating affect) for those who engage in light tobacco use, especially in environments with high cigarette availability.


Assuntos
Fissura , Produtos do Tabaco , Humanos , Adulto Jovem , Adolescente , Adulto , Avaliação Momentânea Ecológica , Adaptação Psicológica , Fumar , Afeto
9.
J Neurosci Res ; 101(5): 563-574, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-34139025

RESUMO

Sex hormones, especially androgens, contribute to sex and gender differences in the brain and behavior. Organizational effects are particularly important because they are thought to be permanent, reflecting hormone exposure during sensitive periods of development. In human beings, they are often studied with natural experiments in which sex hormones are dissociated from other biopsychosocial aspects of development, such as genes and experiences. Indeed, the greatest evidence for organizational effects on sex differences in human behavior comes from studies of females with congenital adrenal hyperplasia (CAH), who have heightened prenatal androgen exposure, female-typical rearing, and masculinized toy play, activity and career interests, spatial skills, and some personal characteristics. Interestingly, however, neuroimaging studies of females with CAH have revealed few neural mechanisms underlying these hormone-behavior links, with the exception of emotion processing; studies have instead shown reduced gray matter volumes and reduced white matter integrity most consistent with other disease-related processes. The goals of this narrative review are to: (a) describe methods for studying prenatal androgen influences, while offering a brief overview of behavioral outcomes; (b) provide a critical methodological review of neuroimaging research on females with CAH; (c) present an illustrative analysis that overcomes methodological limitations of previous work, focusing on person-specific neural reward networks (and their associations with sensation seeking) in women with CAH and their unaffected sisters in order to inform future research questions and approaches that are most likely to reveal organizational hormone effects on brain structure and function.


Assuntos
Hiperplasia Suprarrenal Congênita , Gravidez , Humanos , Feminino , Masculino , Hiperplasia Suprarrenal Congênita/psicologia , Androgênios , Caracteres Sexuais , Encéfalo , Aprendizagem
10.
Curr Dir Psychol Sci ; 31(4): 347-354, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-36213317

RESUMO

Craving (a strong desire to ingest a substance or engage in an activity) is an important topic of study in the field of psychology. Along with being a key symptom of addiction, craving is a potent source of motivation for a wide range of appetitive behaviors. In this article, I offer a perspective regarding the nature of craving that is rooted in the theory of constructed emotion, a contemporary model of how emotions are created by the brain. According to this perspective, craving states emerge when the brain makes predictions that categorize sensory inputs as an instance of craving based on prior experience and the context in which the inputs occur. Using the theory of constructed emotion as a guiding framework, I review various lines of evidence that provide support for this idea. In addition, I offer recommendations for future research that stem from the hypothesis that instances of craving are constructed by the brain in an experience-dependent and situation-specific manner.

11.
Brain Res Bull ; 188: 30-37, 2022 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-35901983

RESUMO

BACKGROUND: Many smokers report attempting to quit each year, yet most relapse, in part due to exposure to smoking-related cues. It is hypothesized that extinction of the cue-drug association could be facilitated through random nicotine delivery (RND), thus making it easier for smokers to quit. The current study aimed to evaluate the effects of RND on smoking cessation-related outcomes including cigarettes per day (CPD) and exhaled carbon monoxide (CO). METHODS: Participants were current smokers (>9 CPD) interested in quitting. Novel trans-mucosal, orally dissolving nicotine films, developed by Bionex Pharmaceuticals, were used in the study. The pharmacokinetic profile of these films was assessed in single (Experiment 1) and multiple-dose (Experiment 2) administrations prior to the smoking cessation study (Experiment 3). In Experiment 3, participants were randomized 1:1:1 to recieve 4 nicotine films per day of either: placebo delivery (0 mg), steady-state delivery (2 mg), or random nicotine delivery (RND) (0 mg or 4 mg). After two weeks, participants were advised to quit (target quit date, TQD) and were followed up 4 weeks later to collect CPD and CO and to measure dependence (Penn State Cigarette Dependence Index; PSCDI) and craving (Questionnaire of Smoking Urges; QSU-Brief). Means and frequencies were used to describe the data and repeated measures ANOVA was used to determine differences between groups. RESULTS: The pharmacokinetic studies (Experiment 1 and 2) demonstrated that the films designed for this study delivered nicotine as expected, with the 4 mg film delivering a nicotine boost of approximately 12.4 ng/mL across both the single and the multiple dose administration studies. The films reduced craving for a cigarette and were well-tolerated, overall, and caused no changes in blood pressure or heart rate. Using these films in the cessation study (Experiment 3) (n = 45), there was a significant overall reduction in cigarettes smoked per day (CPD) and in exhaled CO, with no significant differences across groups (placebo, steady-state, RND). In addition, there were no group differences in dependence or craving. Adverse events included heartburn, hiccups, nausea, and to a lesser extent, vomiting and anxiety and there were no differences across groups. CONCLUSION: Overall, this pilot study found that RND via orally dissolving films was feasible and well tolerated by participants. However, RND participants did not experience a greater reduction in self-reported CPD and exhaled CO, compared with participants in the steady-state and placebo delivery groups. Future studies to evaluate optimal RND parameters with larger sample sizes are needed to fully understand the effect of RND on smoking cessation-related outcomes.


Assuntos
Sistemas Eletrônicos de Liberação de Nicotina , Abandono do Hábito de Fumar , Produtos do Tabaco , Humanos , Nicotina , Projetos Piloto , Fumaça
12.
Sci Transl Med ; 13(594)2021 05 19.
Artigo em Inglês | MEDLINE | ID: mdl-34011629

RESUMO

Genotype-phenotype relationships shape health and population fitness but remain difficult to predict and interpret. Here, we apply an evolutionary action method to de novo missense variants in whole-exome sequences of individuals with autism spectrum disorder (ASD) to unravel genes and pathways connected to ASD. Evolutionary action predicts the impact of missense variants on protein function by measuring the fitness effect based on phylogenetic distances and substitution odds in homologous gene sequences. By examining de novo missense variants in 2384 individuals with ASD (probands) compared to matched siblings without ASD, we found missense variants in 398 genes representing 23 pathways that were biased toward higher evolutionary action scores than expected by random chance; these pathways were involved in axonogenesis, synaptic transmission, and neurodevelopment. The predicted fitness impact of de novo and inherited missense variants in candidate genes correlated with the IQ of individuals with ASD, even for new gene candidates. Taking an evolutionary action method, we detected those missense variants most likely to contribute to ASD pathogenesis and elucidated their phenotypic impact. This approach could be applied to integrate missense variants across a patient cohort to identify genes contributing to a shared phenotype in other complex diseases.


Assuntos
Transtorno do Espectro Autista , Transtorno Autístico , Transtorno do Espectro Autista/genética , Transtorno Autístico/genética , Exoma/genética , Predisposição Genética para Doença , Humanos , Fenótipo , Filogenia
13.
Sci Rep ; 11(1): 4689, 2021 02 25.
Artigo em Inglês | MEDLINE | ID: mdl-33633330

RESUMO

Electronic cigarette use-vaping-is increasingly popular. Various product factors may influence an individual's choice of e-cigarette. To provide an evidence base for e-cigarette regulation, a better understanding of the role different product attributes play in product preferences is needed. Here, we used conjoint analysis to quantify different factors that influence e-cigarettes choices, including flavors, nicotine level, customizability, or use of e-cigarettes to manage appetite/food craving. Young adults completed a set of choice-based conjoint tasks online. Choice Based Conjoint analysis (CBC) was used to determine utility scores for each attribute. Young adults (n = 587) who vaped at least once per week were included in analyses; gender differences were explored. Flavor was the most important attribute (48.1%), followed by product messaging (21.0%) and nicotine level (15.3%). Within flavor, confectionery and fruit flavors had the highest utility scores, while classic menthol and tobacco flavors had the lowest. Men and women differed in flavors, nicotine levels, and product messaging that appealed most. Among young adults who vape weekly, flavor is the most important factor in e-cigarette preferences. Gender also factors into e-cigarette preferences, especially for preferred nicotine level. Understanding why individuals choose particular e-cigarette products will help inform public health efforts and policy making.


Assuntos
Comportamento de Escolha , Sistemas Eletrônicos de Liberação de Nicotina , Paladar , Adolescente , Adulto , Feminino , Humanos , Masculino , Adulto Jovem
14.
Alzheimers Dement ; 17(5): 831-846, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33576571

RESUMO

The strongest genetic risk factor for idiopathic late-onset Alzheimer's disease (LOAD) is apolipoprotein E (APOE) ɛ4, while the APOE ɛ2 allele is protective. However, there are paradoxical APOE ɛ4 carriers who remain disease-free and APOE ɛ2 carriers with LOAD. We compared exomes of healthy APOE ɛ4 carriers and APOE ɛ2 Alzheimer's disease (AD) patients, prioritizing coding variants based on their predicted functional impact, and identified 216 genes with differential mutational load between these two populations. These candidate genes were significantly dysregulated in LOAD brains, and many modulated tau- or ß42-induced neurodegeneration in Drosophila. Variants in these genes were associated with AD risk, even in APOE ɛ3 homozygotes, showing robust predictive power for risk stratification. Network analyses revealed involvement of candidate genes in brain cell type-specific pathways including synaptic biology, dendritic spine pruning and inflammation. These potential modifiers of LOAD may constitute novel biomarkers, provide potential therapeutic intervention avenues, and support applying this approach as larger whole exome sequencing cohorts become available.


Assuntos
Doença de Alzheimer/genética , Apolipoproteína E2/genética , Apolipoproteína E4/genética , Encéfalo/patologia , Fenótipo , Animais , Drosophila , Heterozigoto , Homozigoto , Humanos , Mutação/genética
15.
Addict Biol ; 26(4): e13001, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33508880

RESUMO

Quitting smoking is notoriously difficult. Models of nicotine dependence posit that strength of cognitive control contributes to maintaining smoking abstinence during smoking cessation attempts. We examine the role for large-scale functional brain systems associated with cognitive control in smoking lapse using a novel adaption of a well-validated behavioral paradigm. We use data from 17 daily smokers (five females) after 12 h of smoking abstinence. Participants completed up to 10 sequential 5-min functional magnetic resonance imaging (fMRI) runs, within a single scanning session. After each run, participants decided whether to stay in the scanner in order to earn additional money or to terminate the session in order to smoke a cigarette (i.e., lapse) and forego additional monetary reward. Cox regression results indicate that decreased segregation of the default mode system from the frontoparietal system undermines the ability to resist smoking. This study demonstrates the feasibility of modifying an established behavioral model of smoking lapse behavior for use in the neuro imaging environment, and it provides initial evidence that this approach yields valuable information regarding fine-grained, time-varying changes in patterns of neural activity in the moments leading up to a decision to smoke. Specifically, results lend support to the hypothesis that the time-varying interplay between large-scale functional brain systems associated with cognitive control is implicated in smoking lapse behavior.


Assuntos
Imageamento por Ressonância Magnética/métodos , Abandono do Hábito de Fumar/psicologia , Adulto , Fumar Cigarros/psicologia , Cognição , Fissura , Estudos de Viabilidade , Feminino , Lobo Frontal/diagnóstico por imagem , Humanos , Masculino , Motivação , Recidiva , Recompensa , Fumantes/psicologia , Tabagismo/psicologia
16.
Brain Imaging Behav ; 15(5): 2254-2268, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33405095

RESUMO

Human cognitive performance is often disrupted by distractions related to aversive stimuli and affective states, but, paradoxically, there is also evidence to suggest that high working memory demands reduce the impact of aversive distraction. Previous empirical work suggests this latter effect occurs because working memory demands reduce attention to off-task processes, but the brain regions that mediate this effect remain uncertain. The current study utilizes a novel distraction manipulation involving unpleasant odorants to identify neural structures that buffer performance from aversive distraction under high working memory demands, and to clarify their connectivity in this context. Twenty-one healthy young adults (12 women) completed a verbal n-back task under two levels of load and were concurrently exposed to either room air or aversive odorants. Three brain regions displayed increases in neural responses to olfactory distractors under high load only; the left dorsolateral prefrontal cortex, the left ventrolateral prefrontal cortex and right cerebellar Crus I. Of these regions, only the ventrolateral prefrontal cortex also displayed context-specific connectivity with a region thought to be involved in off-task processes: the dorsomedial prefrontal cortex. Overall, results suggest that, under high working memory demands, areas of the prefrontal cortex and cerebellum shield cognition from aversive distraction, potentially through interactions with brain structures involved in off-task processes.


Assuntos
Imageamento por Ressonância Magnética , Memória de Curto Prazo , Encéfalo/diagnóstico por imagem , Mapeamento Encefálico , Feminino , Humanos , Córtex Pré-Frontal , Adulto Jovem
17.
Nicotine Tob Res ; 23(2): 327-333, 2021 01 22.
Artigo em Inglês | MEDLINE | ID: mdl-32877533

RESUMO

INTRODUCTION: Very light daily smoking is increasingly common among young adults. Evidence suggests that levels of nicotine dependence vary significantly among young adults who engage in very light daily smoking. However, the links between dependence and clinically relevant outcomes (eg, lapse) in this population remain unclear. The goal of this study was to address this gap by evaluating how well different nicotine dependence scales predict lapse behavior among very light daily smoking young adults. AIMS AND METHODS: Very light daily smokers (1-5 cigarettes/day) aged 18-25 participated in an initial laboratory session, during which nicotine dependence was assessed using four commonly used measures: the FagerstrÓ§m Test for Cigarette Dependence (FTCD), the Hooked On Nicotine Checklist (HONC), the Transdisciplinary Tobacco Use Research Centers (TTURC) Nicotine Dependence Inventory, and the Wisconsin Inventory of Smoking Dependence Motives (WISDM). After a baseline period, eligible participants (n = 40) completed a 10-day abstinence incentive period in which they attempted to refrain from smoking to earn monetary rewards. Cox proportional hazards models were used to test whether dependence predicted days to first lapse. RESULTS: FTCD scores significantly predicted days to lapse, as did scores on the FTCD item assessing time to first cigarette of the day (TTFC). No other dependence measures predicted time to lapse. Both the FTCD and TTFC continued to independently predict time to lapse after controlling for smoking frequency and duration. CONCLUSIONS: The FTCD may be a particularly useful tool for capturing clinically meaningful variability in nicotine dependence among young adults who engage in very light daily smoking. IMPLICATIONS: This is the first study to directly link self-reported nicotine dependence with the ability to achieve and maintain abstinence among very light daily smoking young adults. The results may aid clinicians in selecting among variable measures of nicotine dependence when assessing and treating this population.


Assuntos
Fumantes/psicologia , Fumar/epidemiologia , Produtos do Tabaco/estatística & dados numéricos , Tabagismo/epidemiologia , Adolescente , Adulto , Feminino , Humanos , Masculino , Motivação , Autorrelato , Fumar/psicologia , Abandono do Hábito de Fumar/métodos , Tabagismo/psicologia , Wisconsin/epidemiologia , Adulto Jovem
18.
Front Psychol ; 11: 1729, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32793062

RESUMO

Food images are routinely used to investigate the cognitive and neurobiological mechanisms of eating behaviors, but there is a lack of standardized image sets for use in children, which limits cross-study comparisons. To address this gap, we developed a set of age-appropriate images that included 30 high-energy-dense (ED) foods (>2.00 kcal/g), 30 low-ED foods (<1.75 kcal/g), and 30 office supplies photographed in two amounts (i.e., "larger" and "smaller"). Preliminary testing was conducted with children (6-10 years) to assess recognition, emotional valence (1 = very sad, 5 = very happy), and excitability (1 = very bored, 5 = very excited). After the initial testing, 10 images with low recognition were replaced; thus, differences between Image Set 1 and Image Set 2 were analyzed. Thirty (n = 30, mean age 8.3 ± 1.2 years) children rated Set 1, and a different cohort of 29 children (mean age 8.1 ± 1.1 years) rated Set 2. Changes made between image sets improved recognition of low-ED foods (Set 1 = 88.3 ± 10.5% vs. Set 2 = 95.6 ± 10.6%; p < 0.0001) and office supplies (83.7 ± 10.5 vs. 93.0 ± 10.6%; p < 0.0001). For the revised image set, children recognized more high-ED foods (98.4 ± 10.6%) than low-ED foods (95.6 ± 10.6%; p < 0.05) and office supplies (93.0 ± 10.6%; p < 0.0001). Recognition also improved with age (p < 0.001). Excitability and emotional valence scores were greater for high-ED foods compared with both low-ED foods and office supplies (p < 0.0001 for both). However, child fullness ratings influenced the relationship between excitability/emotional valence and category of item (p < 0.002). At the lowest fullness level, high-ED foods were rated the highest in both excitability and emotional valence, followed by low-ED foods and then office supplies. At the highest fullness level, high-ED foods remained the highest in excitability and emotional valence, but ratings for low-ED foods and office supplies were not different. This suggests that low-ED foods were more exciting and emotionally salient (relative to office supplies) when children were hungry. Ratings of recognition, excitability, and emotional valence did not differ by image amount. This new, freely available, image set showed high recognition and expected differences between image category for emotional valence and excitability. When investigating children's responsiveness to food cues, specifically energy density, it is essential for investigators to account for potential influences of child age and satiety level.

19.
Addict Behav Rep ; 11: 100262, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32467851

RESUMO

Choice bundling is a behavioral economic strategy designed to reduce excessive delay discounting and bolster self-control. Choice bundling entails aggregating a series of individual, identical intertemporal decisions (e.g., should I smoke today?) into a single choice (e.g., should I smoke this month?). In this brief review, we succinctly summarize delay discounting and how it has been linked to lapses in self-control, using substance use as an exemplar. Next, we describe how choice bundling may theoretically work to counter excess discounting rates. Finally, we review the extant empirical research on choice bundling and offer recommendations for future research.

20.
Artif Organs ; 44(6): 584-593, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31912510

RESUMO

With the incidence of end-stage heart failure steadily increasing, the need for a practical total artificial heart (TAH) has never been greater. Continuous flow TAHs (CFTAH) are being developed using rotary blood pumps (RBPs), leveraging their small size, mechanical simplicity, and excellent durability. To completely replace the heart with currently available RBPs, two are required; one for providing pulmonary flow and one for providing systemic flow. To prevent hazardous states, it is essential to maintain balance between the pulmonary and systemic circulation at a wide variety of physiologic states. In this study, we investigated factors determining a CFTAH's inherent ability to balance systemic and pulmonary flow passively, without active management of pump rotational speed. Four different RBPs (ReliantHeart HA5, Thoratec HMII, HeartWare HVAD, and Ventracor VentrAssist) were used in various combinations to construct CFTAHs. Each CFTAH's ability to autonomously maintain pressures and flows within defined ranges was evaluated in a hybrid mock loop as systemic and pulmonary vascular resistance (PVR) were changed. The resistance box, a method to quantify the range of vascular resistances that can be safely supported by a CFTAH, was used to compare different CFTAH configurations in an efficient and predictive way. To reduce the need for future in vitro tests and to aid in their analysis, a novel analytical evaluation to predict the resistance box of various CFTAH configurations was also performed. None of the investigated CFTAH configurations fully satisfied the predefined benchmarks for inherent flow balancing, with the VentrAssist (left) and HeartAssist 5 (right) offering the best combination. The extent to which each CFTAH was able to autonomously maintain balance was determined by the pressure sensitivity of each RPB: the sensitivity of outflow to changes in the pressure head. The analytical model showed that by matching left and right pressure sensitivity the inherent balancing performance can be improved. These findings may ultimately lead to a reduced need for manual speed changes or active control systems.


Assuntos
Circulação Sanguínea/fisiologia , Desenho de Equipamento , Insuficiência Cardíaca/cirurgia , Coração Artificial , Modelos Cardiovasculares , Hemodinâmica/fisiologia , Humanos , Circulação Pulmonar
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA