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1.
Hum Brain Mapp ; 45(12): e26807, 2024 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-39185739

RESUMO

Enactive cognition emphasizes co-constructive roles of humans and their environment in shaping cognitive processes. It is specifically engaged in the mental simulation of behaviors, enhancing the connection between perception and action. Here we investigated the core network of brain regions involved in enactive cognition as applied to mental simulations of physical exercise. We used a neuroimaging paradigm in which participants (N = 103) were required to project themselves running or plogging (running while picking-up litter) along an image-guided naturalistic trail. Using both univariate and multivariate brain imaging analyses, we find that a broad spectrum of brain activation discriminates between the mental simulation of plogging versus running. Critically, we show that self-reported ratings of daily life running engagement and the quality of mental simulation (how well participants were able to imagine themselves running) modulate the brain reactivity to plogging versus running. Finally, we undertook functional connectivity analyses centered on the insular cortex, which is a key region in the dynamic interplay between neurocognitive processes. This analysis revealed increased positive and negative patterns of insular-centered functional connectivity in the plogging condition (as compared to the running condition), thereby confirming the key role of the insular cortex in action simulation involving complex sets of mental mechanisms. Taken together, the present findings provide new insights into the brain networks involved in the enactive mental simulation of physical exercise.


Assuntos
Mapeamento Encefálico , Encéfalo , Imageamento por Ressonância Magnética , Corrida , Humanos , Masculino , Corrida/fisiologia , Feminino , Adulto Jovem , Adulto , Encéfalo/diagnóstico por imagem , Encéfalo/fisiologia , Imaginação/fisiologia , Vias Neurais/fisiologia , Vias Neurais/diagnóstico por imagem
2.
Addict Biol ; 29(3): e13389, 2024 03.
Artigo em Inglês | MEDLINE | ID: mdl-38516877

RESUMO

With the advent of digital technologies, online sports betting is spurring a fast-growing expansion. In this study, we examined how sports betting availability modulates the brain connectivity of frequent sports bettors with [problem bettors (PB)] or without [non-problem bettors (NPB)] problematic sports betting. We conducted functional connectivity analyses centred on the ventral anterior insular cortex (vAI), a brain region playing a key role in the dynamic interplay between reward-based processes. We re-analysed a dataset on sports betting availability undertaken in PB (n = 30) and NPB (n = 35). Across all participants, we observed that sports betting availability elicited positive vAI coupling with extended clusters of brain activation (encompassing the putamen, cerebellum, occipital, temporal, precentral and central operculum regions) and negative vAI coupling with the orbitofrontal cortex. Between-group analyses showed increased positive vAI coupling in the PB group, as compared with the NPB group, in the left lateral occipital cortex, extending to the left inferior frontal gyrus, the anterior cingulate gyrus and the right frontal pole. Taken together, these results are in line with the central assumptions of triadic models of addictions, which posit that the insular cortex plays a pivotal role in promoting the drive and motivation to get a reward by 'hijacking' goal-oriented processes toward addiction-related cues. Taken together, these findings showed that vAI functional connectivity is sensitive not only to gambling availability but also to the status of problematic sport betting.


Assuntos
Jogo de Azar , Esportes , Humanos , Córtex Insular , Encéfalo , Motivação
3.
J Gambl Stud ; 39(1): 159-182, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35397748

RESUMO

Psychological theories consider autonomic arousal to be a reinforcer for problem gambling. Structural characteristics such as near-misses, which are non-win events that come close to a real win, have been shown to elicit win-like responses while increasing motivation and gambling persistence. This study investigated the autonomic and subjective responses of young adults to different gambling outcomes. This study also investigated sex differences in autonomic and subjective responses to different gambling outcomes.Participants from Sweden (n = 270) performed a computerized slot machine task that produced wins, near-misses (before and after payline) and full-misses. Phasic measurements of heart rate (HR) and skin conductance responses (SCR) were recorded during gambling performance and ratings of perceived chance of winning, pleasure and motivation to play were collected following each gambling outcome.Autonomic responses differed across slot machine outcomes as indicated by HR and SCR. Compared with other gambling outcomes, near-misses elicited the largest HR accelerations, and they also elicited larger HR decelerations and SCRs relative to full-misses. Near-misses before and after payline elicited differential psychophysiological responses and subjective reports, suggesting different emotional processing of near-miss subtypes. Females showed increased SCRs and motivation following win outcomes compared with males.In conclusion, wins, near-misses and full-misses generate differential physiological and subjective responses among young adults. Autonomic responses to wins differed between male and female players, emphasizing the need to consider sex differences when investigating the role of autonomic arousal in gambling.


Assuntos
Jogo de Azar , Humanos , Feminino , Masculino , Adulto Jovem , Jogo de Azar/psicologia , Nível de Alerta , Emoções , Frequência Cardíaca , Motivação
4.
Addict Biol ; 27(1): e13070, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34263512

RESUMO

Reduced anticipatory reward-related activity, especially in the ventral striatum (VS), may underly adolescent vulnerability to develop nicotine dependence. It remains unclear whether nicotine uptake caused by environmental tobacco smoke (ETS) exposure, known to be associated with future smoking, might prompt similar changes in the brain's reward system, rendering adolescents vulnerable for development of nicotine dependence. To address this question, we tested whether current ETS exposure and monthly smoking are associated with VS hypoactivity for non-drug rewards in experimental smoking adolescents. One-hundred adolescents performed a monetary incentive delay task while brain activity was measured using fMRI. To test the hypothesized relationship, we used a variety of approaches: (1) a whole-brain voxel-wise approach, (2) an region-of-interest approach in the VS using frequentist and Bayesian statistics and (3) a small volume voxel-wise approach across the complete striatum. The results converged in revealing no significant relationships between monthly smoking, ETS exposure and reward-related brain activation across the brain or in the (ventral) striatum specifically. However, Bayesian statistics showed only anecdotal evidence for the null hypothesis in the VS, providing limited insight into the (non-)existence of the hypothesized relationship. Based on these results, we speculate that blunted VS reward-related activity might only occur after relatively high levels of exposure or might be associated with more long term effects of smoking. Future studies would benefit from even larger sample sizes to reliably distinguish between the null and alternative models, as well as more objective measures of (environmental) smoking via using devices such as silicone wristbands.


Assuntos
Recompensa , Fumantes/estatística & dados numéricos , Poluição por Fumaça de Tabaco/estatística & dados numéricos , Fumar Tabaco/epidemiologia , Estriado Ventral/diagnóstico por imagem , Adolescente , Teorema de Bayes , Relação Dose-Resposta a Droga , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Motivação , Tabagismo , Adulto Jovem
5.
Neuroimage ; 242: 118478, 2021 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-34403744

RESUMO

Understanding how the brain processes reward is an important and complex endeavor, which has involved the use of a range of complementary neuroimaging tools, including electroencephalography (EEG). EEG has been praised for its high temporal resolution but, because the signal recorded at the scalp is a mixture of brain activities, it is often considered to have poor spatial resolution. Besides, EEG data analysis has most often relied on event-related potentials (ERPs) which cancel out non-phase locked oscillatory activity, thus limiting the functional discriminative power of EEG attainable through spectral analyses. Because these three dimensions -temporal, spatial and spectral- have been unequally leveraged in reward studies, we argue that the full potential of EEG has not been exploited. To back up our claim, we first performed a systematic survey of EEG studies assessing reward processing. Specifically, we report on the nature of the cognitive processes investigated (i.e., reward anticipation or reward outcome processing) and the methods used to collect and process the EEG data (i.e., event-related potential, time-frequency or source analyses). A total of 359 studies involving healthy subjects and the delivery of monetary rewards were surveyed. We show that reward anticipation has been overlooked (88% of studies investigated reward outcome processing, while only 24% investigated reward anticipation), and that time-frequency and source analyses (respectively reported by 19% and 12% of the studies) have not been widely adopted by the field yet, with ERPs still being the dominant methodology (92% of the studies). We argue that this focus on feedback-related ERPs provides a biased perspective on reward processing, by ignoring reward anticipation processes as well as a large part of the information contained in the EEG signal. Finally, we illustrate with selected examples how addressing these issues could benefit the field, relying on approaches combining time-frequency analyses, blind source separation and source localization.


Assuntos
Antecipação Psicológica/fisiologia , Eletroencefalografia/métodos , Recompensa , Encéfalo/fisiologia , Potenciais Evocados/fisiologia , Humanos , Motivação
6.
Addict Biol ; 26(4): e12996, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-35394691

RESUMO

The unprecedented development and ubiquity of sports betting constitute an emerging public health concern. It is crucial to provide markers that could help to better identify people experiencing sports betting-related harms. The current study investigated whether problem gambling status, sports betting passion, and trait-self-control modulate brain reactivity to sports betting cues. Sixty-five frequent sports bettors (35 "nonproblem bettors" and 30 "problem bettors") were exposed to cues representing real upcoming sport events (with varying levels of winning confidence) that were made available or blocked for betting, during functional magnetic resonance imaging (fMRI) recording. Sports betting passion and trait-self-control were assessed using self-report scales. Sport events nonavailable for betting elicited higher insular and striatal activation in problem bettors, as compared with nonproblem bettors. Within a large cluster encompassing the ventral striatum, hippocampus, and amygdala, lower trait-self-control was associated with increased brain reactivity to sport events with high levels of winning confidence that were nonavailable for betting. No significant effect of sports betting passion was observed. These findings suggest that sports bettors' brain reactivity to gambling unavailability might be a relevant marker of sports betting-related harms, as well as of blunted trait-self-control.


Assuntos
Jogo de Azar , Esportes , Encéfalo/diagnóstico por imagem , Emoções , Jogo de Azar/diagnóstico por imagem , Humanos , Imageamento por Ressonância Magnética
7.
Eur J Neurosci ; 51(6): 1491-1503, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31498505

RESUMO

Alcohol is mainly consumed in social settings, in which people often adapt their drinking behaviour to that of others, also called imitation of drinking. Yet, it remains unclear what drives this drinking in a social setting. In this study, we expected to see stronger brain and behavioural responses to social compared to non-social alcohol cues, and these responses to be associated with drinking in a social setting. The sample consisted of 153 beer-drinking males, aged 18-25 years. Brain responses to social alcohol cues were measured during an alcohol cue-exposure task performed in an fMRI scanner. Behavioural responses to social alcohol cues were measured using a stimulus-response compatibility task, providing an index of approach bias towards these cues. Drinking in a social setting was measured in a laboratory mimicking a bar environment. Specific brain responses to social alcohol cues were observed in the bilateral superior temporal sulcus and the left inferior parietal lobe. There was no approach bias towards social alcohol cues specifically; however, we did find an approach bias towards alcohol (versus soda) cues in general. Brain responses and approach bias towards social alcohol cues were unrelated and not associated with actual drinking. Thus, we found no support for a relation between drinking in a social setting on the one hand, and brain cue-reactivity or behavioural approach biases to social alcohol cues on the other hand. This suggests that, in contrast to our hypothesis, drinking in a social setting may not be driven by brain or behavioural responses to social alcohol cues.


Assuntos
Consumo de Bebidas Alcoólicas , Sinais (Psicologia) , Adolescente , Adulto , Viés , Encéfalo/diagnóstico por imagem , Etanol , Humanos , Masculino , Adulto Jovem
8.
J Sex Med ; 17(9): 1761-1769, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32690426

RESUMO

BACKGROUNDS: The classification of addictions and impulse control disorders is changing as reflected in the 11th version of International Classification of Disorders (WHO, 2018). However, studies focusing on direct comparison of structural brain differences in behavioral and substance addictions are limited. AIM: Here, we contrast gray matter volumes (GMVs) across groups of individuals with compulsive sexual behavior disorder (CSBD), gambling disorder (GD), and alcohol use disorder (AUD) with those with none of these disorders (healthy controls participants; HCs). METHODS: Voxel-based morphometry was used to study brain structure, and severities of addiction symptoms were assessed with questionnaires. To identify brain regions related to severities of addictions, correlations between questionnaire scores and GMVs were computed. MAIN OUTCOME: We collected magnetic resonance imaging (GMVs) data from 26 patients with CSBD, 26 patients with GD, 21 patients with AUD, and 25 HC participants (all heterosexual males; age: 24-60; mean = 34.5, standard deviation = 6.48). RESULTS: Affected individuals (CSBD, GD, AUD) compared with HC participants showed smaller GMVs in the left frontal pole, specifically in the orbitofrontal cortex. The most pronounced differences were observed in the GD and AUD groups, and the least in the CSBD group. In addition, a negative correlation was found between GMVs and disorder severity in the CSBD group. Higher severity of CSBD symptoms was correlated with decreased GMVs in the right anterior cingulate gyrus. CLINICAL IMPLICATIONS: Our findings suggest similarities between CSBD and addictions. STRENGHS AND LIMITIATIONS: This study is the first showing smaller GMVs in 3 clinical groups of CSBD, GD, and AUD. But the study was limited only to heterosexual men. Longitudinal studies should examine the extent to which ventral prefrontal decrements in volume may represent preexisting vulnerability factors or whether they may develop with disorder progression. CONCLUSIONS: Our research extends prior findings in substance use disorders of lower GMVs in prefrontal cortical volumes among 3 clinical groups of patients with specific impulse control (CSBD) and behavioral (GD) and substance (AUD) addictive disorders. The negative correlation between CSBD symptoms and GMV of right anterior cingulate gyrus suggests a link with clinical symptomatology. Draps M, Sescousse G, Potenza MN, et al. Gray Matter Volume Differences in Impulse Control and Addictive Disorders-An Evidence From a Sample of Heterosexual Males. J Sex Med 2020;17:1761-1769.


Assuntos
Comportamento Aditivo , Substância Cinzenta , Adulto , Comportamento Aditivo/diagnóstico por imagem , Córtex Cerebral , Substância Cinzenta/diagnóstico por imagem , Heterossexualidade , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Adulto Jovem
9.
Alcohol Alcohol ; 55(1): 112-120, 2020 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-31603188

RESUMO

AIMS: Psychotic symptoms can occur in the general population, and alcohol use disorder (AUD) is an identified vulnerability factor. However, it remains unclear how AUD is associated with psychotic symptoms, depending on the underlying psychiatric condition.We aimed to compare the prevalence of psychotic symptoms among subjects with different types of psychiatric disorders, i.e. unipolar or bipolar disorders, anxiety disorders, psychotic disorders or no psychiatric disorder, depending on whether or not there was an underlying AUD. METHODS: In a 38,694-subject general population study, we compared the likelihood of occurrence of seven types of psychotic symptoms, depending on the AUD status and the underlying psychiatric disorders, after adjustment for age, sex, marital status, education and income levels. RESULTS: In unipolar depression and anxiety disorders, almost all types of psychotic symptoms were found associated with AUD (odds ratios (ORs) between 1.98 and 2.19). In contrast, in bipolar disorder, only auditory hallucinations were associated with AUD (OR = 2.50). In psychotic disorders, only thought broadcasting was more frequent among subjects with AUD (OR = 1.78). CONCLUSION: Our findings in depression and anxiety disorders are in line with the 'dual diagnosis' concept, which posits that comorbid psychiatric/addictive disorders form distinctive entities that are more frequently associated with non-specific severity factors, here psychotic symptoms. The co-occurrence of AUD in bipolar/psychotic disorders was not associated with a generalized increased occurrence of psychotic symptoms but altered their manifestations with an increased risk of auditory hallucinations for bipolar disorder and thought broadcasting for psychotic disorders.


Assuntos
Alcoolismo/epidemiologia , Transtornos Mentais/epidemiologia , Transtornos Psicóticos/epidemiologia , Fatores Etários , Comorbidade , Feminino , França/epidemiologia , Inquéritos Epidemiológicos , Humanos , Masculino , Prevalência
10.
Addict Biol ; 25(3): e12766, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-31066137

RESUMO

Impaired brain processing of alcohol-related rewards has been suggested to play a central role in alcohol use disorder. Yet, evidence remains inconsistent and mainly originates from studies in which participants passively observe alcohol cues or taste alcohol. Here, we designed a protocol in which beer consumption was predicted by incentive cues and contingent on instrumental action closer to real life situations. We predicted that anticipating and receiving beer (compared with water) would elicit activity in the brain reward network and that this activity would correlate with drinking level across participants. The sample consisted of 150 beer-drinking males, aged 18 to 25 years. Three groups were defined based on alcohol use disorders identification test (AUDIT) scores: light drinkers (n = 39), at-risk drinkers (n = 64), and dependent drinkers (n = 47). fMRI measures were obtained while participants engaged in the beer incentive delay task involving beer- and water-predicting cues followed by real sips of beer or water. During anticipation, outcome notification and delivery of beer compared with water, higher activity was found in a reward-related brain network including the dorsal medial prefrontal cortex, orbitofrontal cortex, and amygdala. Yet, no activity was observed in the striatum, and no differences were found between the groups. Our results reveal that anticipating, obtaining, and tasting beer activates parts of the brain reward network, but that these brain responses do not differentiate between different drinking levels.


Assuntos
Consumo de Bebidas Alcoólicas/fisiopatologia , Alcoolismo/diagnóstico por imagem , Antecipação Psicológica/fisiologia , Cerveja , Encéfalo/diagnóstico por imagem , Motivação , Recompensa , Adolescente , Alcoolismo/fisiopatologia , Tonsila do Cerebelo/diagnóstico por imagem , Tonsila do Cerebelo/fisiopatologia , Encéfalo/fisiopatologia , Corpo Estriado/diagnóstico por imagem , Corpo Estriado/fisiopatologia , Sinais (Psicologia) , Água Potável , Neuroimagem Funcional , Humanos , Imageamento por Ressonância Magnética , Masculino , Vias Neurais/diagnóstico por imagem , Vias Neurais/fisiopatologia , Córtex Pré-Frontal/diagnóstico por imagem , Córtex Pré-Frontal/fisiopatologia , Adulto Jovem
11.
Neuroimage ; 193: 67-74, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30851446

RESUMO

Most studies that have investigated the brain mechanisms underlying learning have focused on the ability to learn simple stimulus-response associations. However, in everyday life, outcomes are often obtained through complex behavioral patterns involving a series of actions. Parallel learning systems might be important to reduce the complexity of the learning problem in such scenarios, as proposed in the framework of hierarchical reinforcement learning (HRL). The key feature of HRL is the decomposition of complex sets of action into subgoals. These subgoals are associated with the computation of pseudo-reward prediction errors (PRPEs), which allow the reinforcement of actions that led to a subgoal before the final goal itself is achieved. Here we wanted to test the hypothesis that, despite not carrying any rewarding value per se, pseudo-rewards might generate a bias in choice behavior in the absence of any advantage. Second, we also hypothesized that this bias might be related to the strength of PRPE striatal representations. In order to test these ideas, we developed a novel decision-making paradigm to assess reward prediction errors (RPEs) and PRPEs in two studies (fMRI study: n = 20; behavioral study: n = 19). Our results show that the participants developed a preference for the most pseudo-rewarding option throughout the task, even though it did not lead to more monetary rewards. fMRI analyses revealed that this preference was predicted by individual differences in the relative striatal sensitivity to PRPEs vs RPEs. Together, our results indicate that pseudo-rewards generate learning signals in the striatum and subsequently bias choice behavior despite their lack of association with actual reward.


Assuntos
Comportamento de Escolha/fisiologia , Corpo Estriado/fisiologia , Tomada de Decisões/fisiologia , Reforço Psicológico , Recompensa , Feminino , Humanos , Imageamento por Ressonância Magnética/métodos , Masculino , Adulto Jovem
12.
Eur J Neurosci ; 47(9): 1081-1086, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29514419

RESUMO

Dopamine is central to a number of cognitive functions and brain disorders. Given the cost of neurochemical imaging in humans, behavioural proxy measures of dopamine have gained in popularity in the past decade, such as spontaneous eye blink rate (sEBR). Increased sEBR is commonly associated with increased dopamine function based on pharmacological evidence and patient studies. Yet, this hypothesis has not been validated using in vivo measures of dopamine function in humans. To fill this gap, we measured sEBR and striatal dopamine synthesis capacity using [18 F]DOPA PET in 20 participants (nine healthy individuals and 11 pathological gamblers). Our results, based on frequentist and Bayesian statistics, as well as region-of-interest and voxel-wise analyses, argue against a positive relationship between sEBR and striatal dopamine synthesis capacity. They show that, if anything, the evidence is in favour of a negative relationship. These results, which complement findings from a recent study that failed to observe a relationship between sEBR and dopamine D2 receptor availability, suggest that caution and nuance are warranted when interpreting sEBR in terms of a proxy measure of striatal dopamine.


Assuntos
Piscadela/fisiologia , Corpo Estriado/metabolismo , Dopamina/metabolismo , Receptores de Dopamina D2/metabolismo , Adulto , Olho/metabolismo , Jogo de Azar/metabolismo , Humanos , Masculino , Pessoa de Meia-Idade , Tomografia por Emissão de Pósitrons/métodos
13.
J Neurosci ; 35(4): 1648-58, 2015 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-25632140

RESUMO

Experienced value representations within the human orbitofrontal cortex (OFC) are thought to be organized through an antero-posterior gradient corresponding to secondary versus primary rewards. Whether this gradient depends upon specific morphological features within this region, which displays considerable intersubject variability, remains unknown. To test the existence of such relationships, we performed a subject-by-subject analysis of fMRI data taking into account the local morphology of each individual. We tested 38 subjects engaged in a simple incentive delay task manipulating both monetary and visual erotic rewards, focusing on reward outcome (experienced value signal). The results showed reliable and dissociable primary (erotic) and secondary (monetary) experienced value signals at specific OFC sulci locations. More specifically, experienced value signal induced by monetary reward outcome was systematically located in the rostral portion of the medial orbital sulcus. Experienced value signal related to erotic reward outcome was located more posteriorly, that is, at the intersection between the caudal portion of the medial orbital sulcus and transverse orbital sulcus. Thus, the localizations of distinct experienced value signals can be predicted from the organization of the human orbitofrontal sulci. This study provides insights into the anatomo-functional parcellation of the anteroposterior OFC gradient observed for secondary versus primary rewards because there is a direct relationship between value signals at the time of reward outcome and unique OFC sulci locations.


Assuntos
Mapeamento Encefálico , Motivação/fisiologia , Córtex Pré-Frontal/anatomia & histologia , Córtex Pré-Frontal/fisiologia , Recompensa , Adulto , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Imageamento por Ressonância Magnética , Masculino , Oxigênio/sangue , Estimulação Luminosa , Comportamento Sexual/psicologia , Adulto Jovem
15.
J Neurosci ; 33(45): 17617-23, 2013 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-24198353

RESUMO

Gambling is pertinent to neuroscience research for at least two reasons. First, gambling is a naturalistic and pervasive example of risky decision making, and thus gambling games can provide a paradigm for the investigation of human choice behavior and "irrationality." Second, excessive gambling involvement (i.e., pathological gambling) is currently conceptualized as a behavioral addiction, and research on this condition may provide insights into addictive mechanisms in the absence of exogenous drug effects. This article is a summary of topics covered in a Society for Neuroscience minisymposium, focusing on recent advances in understanding the neural basis of gambling behavior, including translational findings in rodents and nonhuman primates, which have begun to delineate neural circuitry and neurochemistry involved.


Assuntos
Comportamento Aditivo/fisiopatologia , Encéfalo/fisiopatologia , Comportamento de Escolha/fisiologia , Jogo de Azar/fisiopatologia , Humanos , Motivação/fisiologia , Rede Nervosa/fisiopatologia , Neurônios/fisiologia , Recompensa
16.
Brain ; 136(Pt 8): 2527-38, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23757765

RESUMO

Pathological gambling is an addictive disorder characterized by a persistent and compulsive desire to engage in gambling activities. This maladaptive behaviour has been suggested to result from a decreased sensitivity to experienced rewards, regardless of reward type. Alternatively, pathological gambling might reflect an imbalance in the sensitivity to monetary versus non-monetary incentives. To directly test these two hypotheses, we examined how the brain reward circuit of pathological gamblers responds to different types of rewards. Using functional magnetic resonance imaging, we compared the brain responses of 18 pathological gamblers and 20 healthy control subjects while they engaged in a simple incentive task manipulating both monetary and visual erotic rewards. During reward anticipation, the ventral striatum of pathological gamblers showed a differential response to monetary versus erotic cues, essentially driven by a blunted reactivity to cues predicting erotic stimuli. This differential response correlated with the severity of gambling symptoms and was paralleled by a reduced behavioural motivation for erotic rewards. During reward outcome, a posterior orbitofrontal cortex region, responding to erotic rewards in both groups, was further recruited by monetary gains in pathological gamblers but not in control subjects. Moreover, while ventral striatal activity correlated with subjective ratings assigned to monetary and erotic rewards in control subjects, it only correlated with erotic ratings in gamblers. Our results point to a differential sensitivity to monetary versus non-monetary rewards in pathological gambling, both at the motivational and hedonic levels. Such an imbalance might create a bias towards monetary rewards, potentially promoting addictive gambling behaviour.


Assuntos
Encéfalo/fisiopatologia , Jogo de Azar/fisiopatologia , Recompensa , Adulto , Gânglios da Base/fisiopatologia , Neuroimagem Funcional , Jogo de Azar/psicologia , Humanos , Processamento de Imagem Assistida por Computador , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Motivação , Vias Neurais/fisiopatologia , Estimulação Luminosa
17.
Bull Acad Natl Med ; 198(7): 1309-24; discussion 1324-5, 2014 Oct.
Artigo em Francês | MEDLINE | ID: mdl-27120904

RESUMO

Although most people consider gambling as a recreational activity, some individuals lose control and enter into a spiral of compulsive gambling with dramatic consequences. The many similarities with substance addiction have led psychiatrists to redefine pathological gambling as a behavioural addiction. A number of neurobiological hypotheses originating from this framework have been tested in the past ten years, in particular using neuroimaging. Similarly to substance addiction, a number of observations indicate a central role for dopamine in pathological gambling. However the underlying mechanism seems to be different and is still poorly understood. Neuropsychological studies have shown decision-making deficits in pathological gamblers, accompanied by a lack of inhibition and cognitive flexibility. This disruption of so-called "executive functions" is typical of frontal lobe dysfunction. Finally, functional MRI studies have revealed abnormal reactivity within the brain regions of the " reward system ", including the striatum and ventro-medial prefrontal cortex. These regions are over-activated by gambling cues, and under-activated by monetary gains. However, the scarcity and heterogeneity of brain imaging studies currently hinders the development of a coherent neurobiological model of pathological gambling. Further replications and diversification of approaches will be needed in the coming years in order to produce such a model that will have the ability to inform prevention and treatment strategies.


Assuntos
Comportamento Aditivo , Jogo de Azar , Neuroimagem , Neurociências/tendências , Comportamento Aditivo/diagnóstico , Comportamento Aditivo/prevenção & controle , Comportamento Aditivo/psicologia , Comportamento Aditivo/terapia , Encéfalo/patologia , Jogo de Azar/diagnóstico , Jogo de Azar/prevenção & controle , Jogo de Azar/psicologia , Jogo de Azar/terapia , Humanos , Imageamento por Ressonância Magnética , Neuroimagem/métodos , Recompensa
18.
Schizophrenia (Heidelb) ; 10(1): 38, 2024 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-38503766

RESUMO

Schizophrenia is characterized by the misattribution of emotional significance to neutral faces, accompanied by overactivations of the limbic system. To understand the disorder's genetic and environmental contributors, investigating healthy first-degree relatives is crucial. However, inconsistent findings exist regarding their ability to recognize neutral faces, with limited research exploring the cerebral correlates of neutral face processing in this population. Thus, we here investigated brain responses to neutral face processing in healthy first-degree relatives through an image-based meta-analysis of functional magnetic resonance imaging studies. We included unthresholded group-level T-maps from 5 studies comprising a total of 120 first-degree relatives and 150 healthy controls. In sensitivity analyses, we ran a combined image- and coordinate-based meta-analysis including 7 studies (157 first-degree relatives, 207 healthy controls) aiming at testing the robustness of the results in a larger sample of studies. Our findings revealed a pattern of decreased brain responses to neutral faces in relatives compared with healthy controls, particularly in limbic areas such as the bilateral amygdala, hippocampus, and insula. The same pattern was observed in sensitivity analyses. These results contrast with the overactivations observed in patients, potentially suggesting that this trait could serve as a protective factor in healthy relatives. However, further research is necessary to test this hypothesis.

19.
Transl Psychiatry ; 13(1): 386, 2023 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-38092734

RESUMO

Besides playing a central role in neuroinflammation, microglia regulate synaptic development and is involved in plasticity. Converging lines of evidence suggest that these different processes play a critical role in schizophrenia. Furthermore, previous studies reported altered transcription of microglia genes in schizophrenia, while microglia itself seems to be involved in the etiopathology of the disease. However, the regional specificity of these brain transcriptional abnormalities remains unclear. Moreover, it is unknown whether brain and peripheral expression of microglia genes are related. Thus, we investigated the expression of a pre-registered list of 10 genes from a core signature of human microglia both at brain and peripheral levels. We included 9 independent Gene Expression Omnibus datasets (764 samples obtained from 266 individuals with schizophrenia and 237 healthy controls) from 8 different brain regions and 3 peripheral tissues. We report evidence of a widespread transcriptional alteration of microglia genes both in brain tissues (we observed a decreased expression in the cerebellum, associative striatum, hippocampus, and parietal cortex of individuals with schizophrenia compared with healthy controls) and whole blood (characterized by a mixed altered expression pattern). Our results suggest that brain underexpression of microglia genes may represent a candidate transcriptional signature for schizophrenia. Moreover, the dual brain-whole blood transcriptional alterations of microglia/macrophage genes identified support the model of schizophrenia as a whole-body disorder and lend weight to the use of blood samples as a potential source of biological peripheral biomarkers.


Assuntos
Microglia , Esquizofrenia , Humanos , Microglia/metabolismo , Esquizofrenia/metabolismo , Encéfalo/metabolismo , Hipocampo/metabolismo , Biomarcadores/metabolismo
20.
Sci Rep ; 13(1): 17539, 2023 10 16.
Artigo em Inglês | MEDLINE | ID: mdl-37845325

RESUMO

Given that sexual behavior is usually pleasurable and highly rewarding, it is surprising that there is as yet no known research to empirically assess how premature ejaculation (PE) patients respond to the rewarding aspect of sexual behavior. This study was designed to address this issue by evaluating how these men respond to the anticipation and hedonic experience of sexual rewards in comparison to non-sexual rewards. Thirty lifelong PE patients and thirty healthy controls (HCs) performed the incentive delay task manipulating both erotic and monetary rewards. Compared to HCs, lifelong PE patients exhibited significantly faster RTs to erotic cues than to monetary cues during reward anticipation. Meanwhile, hedonic experience ratings after obtaining the actual reward showed that erotic rewards were rated as more pleasant than monetary rewards only by lifelong PE patients, which was driven by a decreased sensitivity to experienced monetary rewards in lifelong PE patients compared to HCs. These findings indicate the existence of dysfunctional reward processing in lifelong PE patients, which is characterized by increased incentive motivation elicited by sexual cues and reduced hedonic impact of nonsexual rewards. This study may offer an insightful clue regarding how PE is related to the abnormal regulation of the rewarding aspect of sexual behavior.


Assuntos
Ejaculação Precoce , Masculino , Humanos , Comportamento Sexual , Motivação , Emoções , Recompensa , Imageamento por Ressonância Magnética , Ejaculação/fisiologia
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