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1.
Diabetes Obes Metab ; 25(12): 3621-3631, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37667658

RESUMO

AIM: This study assessed the impact of dapagliflozin on food intake, eating behaviour, energy expenditure, magnetic resonance imaging (MRI)-determined brain response to food cues and body composition in patients with type 2 diabetes mellitus (T2D). MATERIALS AND METHODS: Patients were given dapagliflozin 10 mg once daily in a randomized, double-blind, placebo-controlled trial with short-term (1 week) and long-term (12 weeks) cross-over periods. The primary outcome was the difference in test meal food intake between long-term dapagliflozin and placebo treatment. Secondary outcomes included short-term differences in test meal food intake, short- and long-term differences in appetite and eating rate, energy expenditure and functional MRI brain activity in relation to food images. We determined differences in glycated haemoglobin, weight, liver fat (by 1 H magnetic resonance spectroscopy) and subcutaneous/visceral adipose tissue volumes (by MRI). RESULTS: In total, 52 patients (43% were women) were randomized; with the analysis of 49 patients: median age 58 years, weight 99.1 kg, body mass index 35 kg/m2 , glycated haemoglobin 49 mmol/mol. Dapagliflozin reduced glycated haemoglobin by 9.7 mmol/mol [95% confidence interval (CI) 3.91-16.27, p = .004], and body weight (-2.84 vs. -0.87 kg) versus placebo. There was no short- or long-term difference in test meal food intake between dapagliflozin and placebo [mean difference 5.7 g (95% CI -127.9 to 139.3, p = .933); 15.8 g (95% CI -147.7 to 116.1, p = .813), respectively] nor in the rate of eating, energy expenditure, appetite, or brain responses to food cues. Liver fat (median reduction -4.7 vs. 1.95%), but not subcutaneous/visceral adipose tissue, decreased significantly with 12 weeks of dapagliflozin. CONCLUSIONS: The reduction in body weight and liver fat with dapagliflozin was not associated with compensatory adaptations in food intake or energy expenditure.


Assuntos
Diabetes Mellitus Tipo 2 , Humanos , Feminino , Pessoa de Meia-Idade , Masculino , Diabetes Mellitus Tipo 2/tratamento farmacológico , Diabetes Mellitus Tipo 2/metabolismo , Hipoglicemiantes/uso terapêutico , Hemoglobinas Glicadas , Estudos Cross-Over , Compostos Benzidrílicos/uso terapêutico , Fígado/diagnóstico por imagem , Fígado/metabolismo , Peso Corporal , Metabolismo Energético , Método Duplo-Cego , Resultado do Tratamento , Glicemia/metabolismo
2.
Appetite ; 157: 104986, 2021 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-33039507

RESUMO

Theoretical models suggest that food-related visual attentional bias (AB) may be related to appetitive motivational states and individual differences in body weight; however, findings in this area are equivocal. We conducted a systematic review and series of meta-analyses to determine if there is a positive association between food-related AB and: (1.) body mass index (BMI) (number of effect sizes (k) = 110), (2.) hunger (k = 98), (3.) subjective craving for food (k = 35), and (4.) food intake (k = 44). Food-related AB was robustly associated with craving (r = 0.134 (95% CI 0.061, 0.208); p < .001), food intake (r = 0.085 (95% CI 0.038, 0.132); p < .001), and hunger (r = 0.048 (95% CI 0.016, 0.079); p = .003), but these correlations were small. Food-related AB was unrelated to BMI (r = 0.008 (95% CI -0.020, 0.035); p = .583) and this result was not moderated by type of food stimuli, method of AB assessment, or the subcomponent of AB that was examined. Furthermore, in a between-groups analysis (k = 22) which directly compared participants with overweight/obesity to healthy-weight control groups, there was no evidence for an effect of weight status on food-related AB (Hedge's g = 0.104, (95% CI -0.050, 0.258); p = .186). Taken together, these findings suggest that food-related AB is sensitive to changes in the motivational value of food, but is unrelated to individual differences in body weight. Our findings question the traditional view of AB as a trait-like index of preoccupation with food and have implications for novel theoretical perspectives on the role of food AB in appetite control and obesity.


Assuntos
Viés de Atenção , Peso Corporal , Sinais (Psicologia) , Humanos , Fome , Motivação
3.
J Nutr ; 150(6): 1619-1630, 2020 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-32271923

RESUMO

BACKGROUND: The reward value of palatable foods is often cited as an important influence on eating behaviors, including intake of sugars. However, human neuroimaging studies have generated conflicting evidence on the basic neural representation of taste and reward responses to caloric sweeteners (sucrose and glucose), and most relevant studies have used small subject numbers. OBJECTIVE: We conducted a systematic review and a coordinate-based meta-analysis of studies reporting brain responses to oral sugar solutions. METHODS: A systematic search of MEDLINE, Scopus, and PsycINFO through October 2019 identified fMRI studies (in healthy human adults, including those with overweight or obesity) assessing differences in responses to purified sweet and nonsweet taste stimuli. Data were extracted with the primary objective of quantifying evidence for the activation of brain regions associated with caloric sweet taste sensation. We used activation likelihood estimation meta-analysis methods. We also performed multiple sensitivity analyses to assess the generality of effects. RESULTS: Of 455 unique articles, 15 met the criteria for inclusion. These contributed to 2 primary meta-analyses: 1) sucrose (13 experiments, 179 coordinates, n = 241) and 2) sucrose + glucose (16 experiments, 209 coordinates, n = 262). Consistent activation was apparent in primary taste areas: insula (69.2% of studies) and opercular cortex (76.9% of studies), precentral gyri (53.9% of studies), and globus pallidus and postcentral gyrus (30.8% of studies for each). Evidence of reward activity (caudate) was seen in the primary analyses (30.8% of studies) but not in sensitivity analysis. CONCLUSIONS: We confirm the importance of primary taste areas for gustatory processing in human adults. We also provide tentative evidence for reward-related caudate activity in relation to the sweet taste of caloric sugars. A number of factors affect the observation and interpretation of brain responses, including reward-related activity. Firm conclusions require confirmation with large data set studies.


Assuntos
Imageamento por Ressonância Magnética/métodos , Edulcorantes , Paladar , Humanos , Funções Verossimilhança , Sacarose
4.
Eur Arch Psychiatry Clin Neurosci ; 269(1): 59-71, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30706169

RESUMO

Regular cannabis use is associated with adverse cognitive and mental health outcomes that have been ascribed to aberrant neuroanatomy in brain regions densely innervated with cannabinoid receptors. Neuroanatomical differences between cannabis users and controls have been assessed in multiple structural magnetic resonance imaging (sMRI) studies. However, there is heterogeneity in the results leading to cautious interpretation of the data so far. We examined the sMRI evidence to date in human cannabis users, to establish more definitely whether neuroanatomical alterations are associated with regular cannabis use. The regional specificity and association with cannabis use indices (i.e. cumulative dosage, duration) were also explored. We systematically reviewed and meta-analysed published sMRI studies investigating regional brain volumes (cortical, subcortical and global) in cannabis users and non-user controls. Three electronic databases were searched (PubMed, Scopus, and PsycINFO). A total of 17 meta-analyses were conducted (one for each cortical, subcortical and global volume) using the generic inverse variance method, whereby standardised mean difference in volume was calculated between users and non-users. Exploratory meta-regressions were conducted to investigate the association between cannabis use indices and regional brain volumes. A total of 30 articles were eligible for inclusion, contributing 106 effect sizes across 17 meta-analyses. Regular cannabis users had significantly smaller volumes of the hippocampus (SMD = 0.14, 95% CIs [0.02, 0.27]; Z = 2.29, p = 0.02, I2 = 74%) and orbitofrontal cortex {medial (SMD = 0.30, 95% CIs [0.15, 0.45]; Z = 3.89, p = 0.0001, I2 = 51%), lateral (SMD = 0.19, 95% CIs [0.07, 0.32]; Z = 3.10, p = 0.002, I2 = 26%)} relative to controls. The volumes of the hippocampus and orbitofrontal cortex were not significantly associated with cannabis duration and dosage. Our findings are consistent with evidence of aberrance in brain regions involved in reward, learning and memory, and motivation circuits in the regular use of substances other than cannabis, pointing to commonality in neurobiological abnormalities between regular users of cannabis and of other substances.


Assuntos
Cannabis/efeitos adversos , Hipocampo , Neuroimagem/estatística & dados numéricos , Córtex Pré-Frontal , Hipocampo/diagnóstico por imagem , Hipocampo/efeitos dos fármacos , Hipocampo/patologia , Humanos , Córtex Pré-Frontal/diagnóstico por imagem , Córtex Pré-Frontal/efeitos dos fármacos , Córtex Pré-Frontal/patologia
5.
Hum Psychopharmacol ; 32(3)2017 05.
Artigo em Inglês | MEDLINE | ID: mdl-28631348

RESUMO

AIMS/OBJECTIVES: Cognitive deficits are now well documented in ecstasy (MDMA) users with type and relative demand of task emerging as important factors. The updating component of executive processes appears to be particularly affected. The study reported here used functional near infrared spectroscopy imaging to investigate changes in cortical haemodynamics during memory updating. METHOD: Twenty ecstasy users and 20 non-users completed verbal and spatial memory updating tasks and brain blood oxygenation and deoxygenation change was measured using functional near infrared spectroscopy. RESULTS: There was no interaction between group and difficulty on the updating tasks, though there was a significant main effect of difficulty on both tasks. The effects of group approached significance on the verbal updating task. There were significant differences in blood oxygenation and deoxygenation change at optodes centred over the right and left dorsolateral prefrontal cortex, with ecstasy users showing greater blood oxygenation than the other groups. DISCUSSION: The lack of a behavioural difference on both tasks but presence of blood oxygenation and deoxygenation changes in letter updating provides support for the notion that ecstasy-polydrug users are investing more effort to achieve the same behavioural output. Total lifetime dose was high, and recency of use was significantly related to most changes, suggesting that heavy and recent use may be particularly detrimental.


Assuntos
Drogas Ilícitas/efeitos adversos , Memória de Curto Prazo/efeitos dos fármacos , N-Metil-3,4-Metilenodioxianfetamina/efeitos adversos , Espectroscopia de Luz Próxima ao Infravermelho/métodos , Transtornos Relacionados ao Uso de Substâncias/diagnóstico , Transtornos Relacionados ao Uso de Substâncias/metabolismo , Adolescente , Adulto , Córtex Cerebral/efeitos dos fármacos , Córtex Cerebral/metabolismo , Usuários de Drogas/psicologia , Feminino , Humanos , Masculino , Memória de Curto Prazo/fisiologia , Estimulação Luminosa/métodos , Adulto Jovem
6.
BMJ Open ; 14(2): e071776, 2024 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-38382965

RESUMO

OBJECTIVES: Occupational moral injury and post-traumatic embitterment disorder (PTED) describe the psychological distress caused by exposure to injustice at work. This meta-analysis aims to determine the prevalence of occupational moral injury and PTED and establish whether prevalence estimates differ depending on occupation. DESIGN: A systematic review and meta-analysis. DATA SOURCES: Google Scholar, PubMed, APA PsycINFO, Web of Science Core Collection, Scopus, ScienceDirect and Sage Journals Online were searched in June 2020 and updated in November 2022. ELIGIBILITY CRITERIA FOR SELECTING STUDIES: Observational studies that measured prevalence or average scores of moral injury, or PTED in any occupational group and any geographical location. DATA EXTRACTION AND SYNTHESIS: Two independent reviewers screened and coded eligible studies. Study design, participant demographics, sampling method, location, measurement tool and prevalence or average scores were extracted. Risk of bias was assessed using the Quality Assessment Checklist for Prevalence Studies tool. Meta-analysis was conducted using random effects models. Results that could not be combined were summarised qualitatively in a narrative synthesis using the Guidance for Systematic Reviews. RESULTS: In total, 88 studies across armed forces and veterans, healthcare, first responders, educators, journalists, child protection service employees, the unemployed, public-sector employees and mixed occupations were included. Studies included in each separate meta-analysis based on the measure used ranged from 2 to 30. The pooled prevalence of clinically relevant moral injury in healthcare professionals was 45%, and exposure to any potentially morally injurious event (PMIE) across occupations was 67%. Exposure to transgressions by others and betrayal was significantly lower in the armed forces than civilian occupations. Pooled prevalence of PTED across occupations was 26%. CONCLUSION: Exposure to PMIEs, moral injury symptoms and PTED are prevalent at work and exposure to transgressions by others and betrayal are more likely in civilian occupations than the armed forces. PROSPERO REGISTRATION NUMBER: CRD42020191766.


Assuntos
Doenças Profissionais , Exposição Ocupacional , Traumatismos Ocupacionais , Transtornos de Estresse Pós-Traumáticos , Criança , Humanos , Transtornos de Estresse Pós-Traumáticos/etiologia , Transtornos de Estresse Pós-Traumáticos/complicações , Doenças Profissionais/etiologia , Prevalência , Exposição Ocupacional/análise , Efeitos Psicossociais da Doença , Organização Mundial da Saúde , Traumatismos Ocupacionais/epidemiologia , Traumatismos Ocupacionais/complicações
7.
Obes Rev ; 25(1): e13643, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37766661

RESUMO

Food marketing impacts the food behaviors of children and adults, but the underpinning neural mechanisms are poorly understood. This systematic review and meta-analysis pooled evidence from neuroimaging studies of exposure to food marketing stimuli (vs. control) on brain activations in children and adults to clarify regions associated with responding. Databases were searched for articles published to March 2022. Inclusion criteria included human functional magnetic resonance imaging (fMRI) studies employing a contrast between a food marketing stimulus and a non-food/non-exposure control, published in English in a peer-reviewed journal, reporting whole brain (not Region of Interest [ROI] only) co-ordinates. Eleven studies met inclusion criteria, of which eight were included in the quantitative synthesis (Activation Likelihood Estimation [ALE] meta-analysis). Food marketing exposures (vs. controls) produced greater activation in two clusters lying across the middle occipital gyrus, lingual gyrus, and cuneus (cluster 1), and the postcentral gyrus, precentral gyrus, and the inferior parietal lobule/supramarginal gyrus (cluster 2). Brain responses to food marketing are most consistently observed in areas relating to visual processing, attention, sensorimotor activity, and emotional processing. Subgroup analyses (e.g., adults vs. children) were not possible because of the paucity of data, and sensitivity analyses highlighted some instability in the clusters; therefore, conclusions remain tentative pending further research.


Assuntos
Encéfalo , Emoções , Adulto , Criança , Humanos , Funções Verossimilhança , Encéfalo/diagnóstico por imagem , Mapeamento Encefálico/métodos , Imageamento por Ressonância Magnética , Bebidas
8.
Behav Brain Res ; 465: 114932, 2024 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-38437921

RESUMO

Previous research investigated cross-modal influence of olfactory stimuli on perception and evaluation of faces. However, little is known about the neural dynamics underpinning this multisensory perception, and no research examined perception for images of oneself, and others, in presence of fragrances. This study investigated the neural mechanisms of olfactory-visual processing using electroencephalography (EEG) and subjective evaluations of self- and other-images. 22 female participants evaluated images of female actors and themselves while being exposed to the fragrance of a commercially available body wash or clean air delivered via olfactometer. Participants rated faces for attractiveness, femininity, confidence and glamorousness on visual analogue scales. EEG data was recorded and event-related potentials (ERPs) associated with onset of face stimuli were analysed to consider effects of fragrance presence on face processing, and interactions between fragrance and self-other image-type. Subjective ratings of confidence, attractiveness and femininity were increased for both image-types in pleasant fragrance relative to clean air condition. ERP components covering early-to-late stages of face processing were modulated by the presence of fragrance. Findings also revealed a cross-modal fragrance-face interaction, with pleasant fragrance particularly affecting ERPs to self-images in mid-latency ERP components. Results showed that the pleasant fragrance of the commercially available body wash impacted how participants perceived faces of self and others. Self- and other-image faces were subjectively rated as more attractive, confident and feminine in the presence of the pleasant fragrance compared to an un-fragranced control. The pleasant fragrance also modulated underlying electrophysiological activity. For the first time, an effect of pleasant fragrance on face perception was observed in the N1 component, suggesting impact within 100 ms. Pleasant fragrance also demonstrated greater impact on subsequent neural processing for self, relative to other-faces. The findings have implications for understanding multisensory integration during evaluations of oneself and others.


Assuntos
Feminilidade , Odorantes , Humanos , Feminino , Beleza , Potenciais Evocados/fisiologia , Eletroencefalografia
9.
Artigo em Inglês | MEDLINE | ID: mdl-38498015

RESUMO

Background: Males and females who consume cannabis can experience different mental health and cognitive problems. Neuroscientific theories of addiction postulate that dependence is underscored by neuroadaptations, but do not account for the contribution of distinct sexes. Further, there is little evidence for sex differences in the neurobiology of cannabis dependence as most neuroimaging studies have been conducted in largely male samples in which cannabis dependence, as opposed to use, is often not ascertained. Methods: We examined subregional hippocampus and amygdala volumetry in a sample of 206 people recruited from the ENIGMA Addiction Working Group. They included 59 people with cannabis dependence (17 females), 49 cannabis users without cannabis dependence (20 females), and 98 controls (33 females). Results: We found no group-by-sex effect on subregional volumetry. The left hippocampal cornu ammonis subfield 1 (CA1) volumes were lower in dependent cannabis users compared with non-dependent cannabis users (p<0.001, d=0.32) and with controls (p=0.022, d=0.18). Further, the left cornu ammonis subfield 3 (CA3) and left dentate gyrus volumes were lower in dependent versus non-dependent cannabis users but not versus controls (p=0.002, d=0.37, and p=0.002, d=0.31, respectively). All models controlled for age, intelligence quotient (IQ), alcohol and tobacco use, and intracranial volume. Amygdala volumetry was not affected by group or group-by-sex, but was smaller in females than males. Conclusions: Our findings suggest that the relationship between cannabis dependence and subregional volumetry was not moderated by sex. Specifically, dependent (rather than non-dependent) cannabis use may be associated with alterations in selected hippocampus subfields high in cannabinoid type 1 (CB1) receptors and implicated in addictive behavior. As these data are cross-sectional, it is plausible that differences predate cannabis dependence onset and contribute to the initiation of cannabis dependence. Longitudinal neuroimaging work is required to examine the time-course of the onset of subregional hippocampal alterations in cannabis dependence, and their progression as cannabis dependence exacerbates or recovers over time.

10.
Physiol Behav ; 271: 114350, 2023 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-37714323

RESUMO

BACKGROUND: Prior research suggests naturalistic single-trial appetitive conditioning may be a potent phenomenon in humans, capable of modulating both motivation and attention. In this study, we aimed to characterise the neural correlates of this phenomenon using functional Magnetic Resonance Imaging (fMRI) paradigms METHODS: Twenty-three healthy adults (12 males) underwent conditioning during which they ate a novel 3D object made from white chocolate (CS+) and handled a similar object made from plastic (CS-). Brain activity was recorded before and after conditioning during a passive viewing paradigm RESULTS: A naturalistic CS+ was rated as more highly craved, better-liked and elicited greater expectancies for chocolate than the CS- after conditioning. An exploration of the interaction between time (pre- and post-conditioning) and CS type (CS+, CS-) during the passive viewing task suggested enhanced activation from pre- to post-conditioning in the right superior frontal gyrus (R.SFG) in response to the CS-. CONCLUSION: Results reveal neural correlates of single-trial appetitive conditioning and highlight a possible role of response inhibition during learning about non-rewards, perhaps optimizing motivated behaviour. These findings contribute to our understanding of the neural mechanisms underpinning rapid reward and non-reward learning, and may inform development of behavioural interventions for reward-driven overeating.


Assuntos
Condicionamento Clássico , Aprendizagem , Adulto , Masculino , Humanos , Condicionamento Clássico/fisiologia , Aprendizagem/fisiologia , Emoções/fisiologia , Motivação , Córtex Pré-Frontal , Imageamento por Ressonância Magnética , Recompensa , Sinais (Psicologia)
11.
Cannabis Cannabinoid Res ; 8(1): 184-196, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-35443799

RESUMO

Introduction: Cannabis use has a high prevalence in young youth and is associated with poor psychosocial outcomes. Such outcomes have been ascribed to the impact of cannabis exposure on the developing brain. However, findings from individual studies of volumetry in youth cannabis users are equivocal. Objectives: Our primary objective was to systematically review the evidence on brain volume differences between young cannabis users and nonusers aged 12-26 where profound neuromaturation occurs, accounting for the role of global brain volumes (GBVs). Our secondary objective was to systematically integrate the findings on the association between youth age and volumetry in youth cannabis users. Finally, we aimed to evaluate the quality of the evidence. Materials and Methods: A systematic search was run in three databases (PubMed, Scopus, and PsycINFO) and was reported using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. We run meta-analyses (with and without controlling for GBV) of brain volume differences between young cannabis users and nonusers. We conducted metaregressions to explore the role of age on volumetric differences. Results: Sixteen studies were included. The reviewed samples included 830 people with mean age 22.5 years (range 14-26 years). Of these, 386 were cannabis users (with cannabis use onset at 15-19 years) and 444 were controls. We found no detectable group differences in any of the GBVs (intracranium, total brain, total white matter, and total gray matter) and regional brain volumes (i.e., hippocampus, amygdala, orbitofrontal cortex, and total cerebellum). Age and cannabis use level did not predict (standardized mean) volume group differences in metaregression. We found little evidence of publication bias (Egger's test p>0.1). Conclusions: Contrary to evidence in adult samples (or in samples mixing adults and youth), previous single studies in young cannabis users, and meta-analyses of brain function in young cannabis users, this early evidence suggests nonsignificant volume differences between young cannabis users and nonusers. While prolonged and long-term exposure to heavy cannabis use may be required to detect gross volume alterations, more studies in young cannabis users are needed to map in detail cannabis-related neuroanatomical changes.


Assuntos
Cannabis , Adulto , Adolescente , Humanos , Adulto Jovem , Imageamento por Ressonância Magnética , Encéfalo , Substância Cinzenta , Neuroimagem
12.
PLoS One ; 18(7): e0286969, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37428744

RESUMO

Forming and comparing subjective values (SVs) of choice options is a critical stage of decision-making. Previous studies have highlighted a complex network of brain regions involved in this process by utilising a diverse range of tasks and stimuli, varying in economic, hedonic and sensory qualities. However, the heterogeneity of tasks and sensory modalities may systematically confound the set of regions mediating the SVs of goods. To identify and delineate the core brain valuation system involved in processing SV, we utilised the Becker-DeGroot-Marschak (BDM) auction, an incentivised demand-revealing mechanism which quantifies SV through the economic metric of willingness-to-pay (WTP). A coordinate-based activation likelihood estimation meta-analysis analysed twenty-four fMRI studies employing a BDM task (731 participants; 190 foci). Using an additional contrast analysis, we also investigated whether this encoding of SV would be invariant to the concurrency of auction task and fMRI recordings. A fail-safe number analysis was conducted to explore potential publication bias. WTP positively correlated with fMRI-BOLD activations in the left ventromedial prefrontal cortex with a sub-cluster extending into anterior cingulate cortex, bilateral ventral striatum, right dorsolateral prefrontal cortex, right inferior frontal gyrus, and right anterior insula. Contrast analysis identified preferential engagement of the mentalizing-related structures in response to concurrent scanning. Together, our findings offer succinct empirical support for the core structures participating in the formation of SV, separate from the hedonic aspects of reward and evaluated in terms of WTP using BDM, and show the selective involvement of inhibition-related brain structures during active valuation.


Assuntos
Encéfalo , Córtex Pré-Frontal , Humanos , Encéfalo/diagnóstico por imagem , Encéfalo/fisiologia , Córtex Pré-Frontal/fisiologia , Comportamento de Escolha/fisiologia , Giro do Cíngulo/fisiologia , Mapeamento Encefálico , Imageamento por Ressonância Magnética
13.
Obes Rev ; 24(9): e13596, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37393517

RESUMO

Dietary temptations and lapses challenge control over eating and act as barriers toward successful weight loss. These are difficult to assess in laboratory settings or with retrospective measures as they occur momentarily and driven by the current environment. A better understanding of how these experiences unfold within real-world dieting attempts could help inform strategies to increase the capacity to cope with the changes in appetitive and affective factors that surround these experiences. We performed a narrative synthesis on the empirical evidence of appetitive and affective outcomes measured using ecological momentary assessment (EMA) during dieting in individuals with obesity and their association with dietary temptations and lapses. A search of three databases (Scopus, Medline, and PsycInfo) identified 10 studies. Within-person changes in appetite and affect accompany temptations and lapses and are observable in the moments precipitating a lapse. Lapsing in response to these may be mediated through the strength of a temptation. Negative abstinence-violation effects occur following a lapse, which negatively impact self-attitudes. Engagement in coping strategies during temptations is effective for preventing lapses. These findings indicate that monitoring changes in sensations during dieting could help identify the crucial moments when coping strategies are most effective for aiding with dietary adherence.


Assuntos
Apetite , Avaliação Momentânea Ecológica , Humanos , Estudos Retrospectivos , Dieta Redutora , Redução de Peso
14.
Exp Neurol ; 347: 113888, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34624331

RESUMO

3,4 Methylenedioxymethamphetamine generally referred to as MDMA or 'ecstasy' is a ring-substituted phenethylamine stimulant which produces powerful empathogenic effects. Use of MDMA remains popular despite prohibition, and potential long-term negative consequences of repeated use. MDMA produces its acute subjective effects primarily by stimulating the release of serotonin via action at the serotonin transporter (SERT). There is evidence that MDMA administration may lead to long lasting neurotoxic effects on serotonin neurons in primates, and reductions in markers of central serotonin axons, and axon terminals in animals. In humans, demonstration of serotonergic neurotoxicity is much more difficult to identify, and much of the research is complicated by confounding issues of polysubstance use, genetic and environmental factors and reliance on self-reports of previous drug use. We do not review the mechanisms for neurotoxicity in detail as they are covered elsewhere in this special issue. There is a large body of literature, however, which has investigated potential cognitive and neurocognitive consequences of repeated MDMA use. Here we review the literature on cognition, and neuroimaging studies that have investigated structural and functional brain changes associated with ecstasy use.


Assuntos
Encéfalo/efeitos dos fármacos , Cognição/efeitos dos fármacos , Alucinógenos/efeitos adversos , N-Metil-3,4-Metilenodioxianfetamina/efeitos adversos , Humanos
15.
Addiction ; 117(12): 2986-3003, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-35638379

RESUMO

BACKGROUND AND AIMS: An initial dose of alcohol can motivate-or prime-further drinking and may precipitate (re)lapse and bingeing. Lab-based studies have investigated the alcohol priming effect; however, heterogeneity in designs has resulted in some inconsistent findings. The aims of this meta-analysis were to (i) determine the pooled effect size for motivation to drink following priming, measured by alcohol consumption and craving, and (ii) examine whether design characteristics influenced any priming effect. METHODS: Literature searches of PsycINFO, PubMed and Scopus in October 2020 (updated October 2021) identified lab-based alcohol priming studies that assessed effect of priming on motivation to drink. A tailored risk-of-bias tool assessed quality of lab-based studies. Random effects meta-analyses were computed on outcome data from 38 studies comparing the effect of a priming dose of alcohol against control on subsequent alcohol consumption/self-reported craving. Study characteristics that might have affected outcomes were design type (within/between-participant), dose of prime, time of motivation assessment, type of control drink (placebo alcohol/soft drink). RESULTS: Relative to control, alcohol had a small-to-moderate priming effect on subsequent alcohol consumption (standardised mean difference [SMD] = 0.336 [95% CI, 0.171, 0.500]) and craving (SMD = 0.431 [95% CI, 0.306, 0.555]). Aspects of study design differentially affected consumption and craving. The size of the priming dose had no effect on consumption, but larger doses were sometimes associated with greater craving (with craving generally following the blood alcohol curve). Alcohol priming effects for consumption, but not craving, were smaller when compared with placebo, relative to soft drink, control. CONCLUSIONS: Lab-based alcohol priming studies are a valid paradigm from which to investigate the impact of acute intoxication on alcohol motivation. Designs are needed that assess the impact of acute consumption on motivation to drink in more varied and realistic ways.


Assuntos
Fissura , Motivação , Humanos , Etanol , Consumo de Bebidas Alcoólicas , Autorrelato
16.
Eur J Intern Med ; 93: 3-7, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-33461826

RESUMO

Weight regain following weight loss is frequent problem that people with obesity face. This weight recidivism is often attributed to the lack of compliance with appropriate food habits and exercise. On the contrary, it is known that body weight and fat mass are regulated by numerous physiological mechanisms, far beyond voluntary food intake and physical exercise. Thus, the aim of this paper is to review the main peripheral and central mechanisms involved in weight regain. Gut hormone secretion profiles impact upon predisposition to weight regain according to an individual variability, although it is recognised a usual pattern of compensatory changes: a reduction in anorectic hormones secretion and an increase in orexigenic hormone. These changes lead to both increased appetite and reward value of food leading to increased energye intake. In addition, resting energy expenditure after weight loss is lower than expected according to body composition changes. This gap between observed and predicted energy expenditure following weight loss is named metabolic adaptation, which has been suggested to explain partly weight regain. This complicated scenario, beyond patient motivation, makes weight regain a challenge in long-term management interventions in patients with obesity.


Assuntos
Ingestão de Energia , Redução de Peso , Peso Corporal , Metabolismo Energético , Humanos , Obesidade , Aumento de Peso
17.
Drug Alcohol Depend ; 226: 108913, 2021 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-34315105

RESUMO

BACKGROUND: Coronavirus (COVID-19) resulted in lockdown measures in the UK, which has impacted alcohol use. Alcohol is often used as a coping mechanism and there are public health concerns regarding excessive consumption due to the pandemic. We aimed to longitudinally assess drinking behaviors, and associated factors, during the first UK government-mandated lockdown. METHODS: An online survey was distributed through social media (8th April 2020, onwards). Fortnightly follow up surveys were emailed to participants. The primary outcome measure was 'weekly unit consumption' and data was collected on a range of potentially related factors: demographics, factors relating to COVID-19 (e.g., health, work status), drinking motives, context of drinking, drinking intentions, mood, depression and anxiety. FINDINGS: A total of 539 self-selected participants completed the baseline survey, with 186 completing at least 3 follow up surveys for multilevel modelling analysis. Personal coping motives, anxiety, drinking at home alone, and drinking at home with others were positively associated with alcohol consumption during lockdown. The following baseline measures also predicted increased consumption: male gender, lower education, and higher AUDIT scores (based on behavior prior to lockdown). Findings were consistent when utilizing an inverse probability weight to account for predictors of attrition (female, younger age, higher baseline AUDIT scores). CONCLUSIONS: Those already drinking at hazardous levels were more likely to increase their consumption, as were those who were drinking to cope. As we recover from the pandemic, there is a need for widespread alcohol support, and certain groups may need targeted support.


Assuntos
COVID-19 , Saúde Mental , Adaptação Psicológica , Consumo de Bebidas Alcoólicas/epidemiologia , Controle de Doenças Transmissíveis , Feminino , Humanos , Masculino , Motivação , SARS-CoV-2
18.
Artigo em Inglês | MEDLINE | ID: mdl-33716043

RESUMO

Cocaine dependence (CD) is highly comorbid with personality disorders, with implications for poorer treatment response. The neurobiological mechanisms of this comorbidity are unclear. We aimed to test the role of comorbid personality disorders in the neuroanatomy of CD. We examined 4 groups using high-resolution structural neuroimaging, psychological questionnaires and cognitive tests: CD (n = 19), CD and personality disorder type B (CD + B, n = 21), CD and personality disorder C (CD + C, n = 13) and 21 controls. We compared groups in neuroanatomy and hypothesised that (i) CD would show altered striatal areas ascribed to reward processing (i.e., accumbens, caudate and putamen), (ii) CD + B and CD + C would show altered areas supporting emotional regulation/social valuation and anxiety/avoidance (i.e., OFC and amygdala). The CD + B group had larger caudate volumes than CD (p = .01, d = 0.94) and reduced lateral OFC thickness than CD + C (p = .056, d = 0.71). Exploratory correlations showed that altered neural integrity of the OFC and of the caudate nucleus in these groups exacerbated with worse personality disorder severity and impulsivity scores. CD with and without comorbid personality disorders may have partially distinct underlying mechanisms and targets for treatment.


Assuntos
Transtornos Relacionados ao Uso de Cocaína , Comorbidade , Neuroanatomia , Neuroimagem , Transtornos da Personalidade , Adulto , Núcleo Caudado , Transtornos Relacionados ao Uso de Cocaína/epidemiologia , Transtornos Relacionados ao Uso de Cocaína/psicologia , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Testes Neuropsicológicos , Transtornos da Personalidade/epidemiologia , Transtornos da Personalidade/psicologia , Inquéritos e Questionários
19.
Neurosci Biobehav Rev ; 119: 468-480, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-33086131

RESUMO

Psychological factors may explain why some people develop obesity and others remain a normal weight during their life course. We use an umbrella review approach to build an evidence-based map of the psychological correlates of heavier body weight. Synthesising findings from 42 meta-analyses that have examined associations between psychological factors and heavier body weight, we assessed level of evidence for a range of cognitive, psychosocial and mental health individual difference factors. There is convincing evidence that impaired mental health is associated with heavier body weight and highly suggestive evidence that numerous cognitive factors are associated with heavier body weight. However, the relatively low methodological quality of meta-analyses resulted in lower evidential certainty for most psychosocial factors. Psychological correlates of heavier body weight tended to be small in statistical size and on average, people with obesity were likely to be more psychologically similar than different to people with normal weight. We consider implications for understanding the development of heavier body weight and identifying effective public health interventions to reduce obesity.


Assuntos
Saúde Mental , Obesidade , Humanos
20.
Soc Cogn Affect Neurosci ; 15(7): 709-723, 2020 09 24.
Artigo em Inglês | MEDLINE | ID: mdl-32608498

RESUMO

BACKGROUND: Empathy for pain is a complex phenomenon incorporating sensory, cognitive and affective processes. Functional neuroimaging studies indicate a rich network of brain activations for empathic processing. However, previous research focused on core activations in bilateral anterior insula (AI) and anterior cingulate/anterior midcingulate cortex (ACC/aMCC) which are also typically present during nociceptive (pain) processing. Theoretical understanding of empathy would benefit from empirical investigation of shared and contrasting brain activations for empathic and nociceptive processing. METHOD: Thirty-nine empathy for observed pain studies (1112 participants; 527 foci) were selected by systematic review. Coordinate based meta-analysis (activation likelihood estimation) was performed and novel contrast analyses compared neurobiological processing of empathy with a comprehensive meta-analysis of 180 studies of nociceptive processing (Tanasescu et al., 2016). RESULTS: Conjunction analysis indicated overlapping activations for empathy and nociception in AI, aMCC, somatosensory and inferior frontal regions. Contrast analysis revealed increased likelihood of activation for empathy, relative to nociception, in bilateral supramarginal, inferior frontal and occipitotemporal regions. Nociception preferentially activated bilateral posterior insula, somatosensory cortex and aMCC. CONCLUSION: Our findings support the likelihood of shared and distinct neural networks for empathic, relative to nociceptive, processing. This offers succinct empirical support for recent tiered or modular theoretical accounts of empathy.


Assuntos
Encéfalo/diagnóstico por imagem , Empatia/fisiologia , Rede Nervosa/diagnóstico por imagem , Dor/diagnóstico por imagem , Mapeamento Encefálico , Neuroimagem Funcional , Humanos , Imageamento por Ressonância Magnética , Dor/psicologia
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