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1.
Sci Rep ; 14(1): 8717, 2024 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-38622142

RESUMO

Work shows that sexually-diverse individuals face high rates of early life adversity and in turn increased engagement in behavioral outcomes traditionally associated with adversity, such as sexual risk taking. Recent theoretical work suggests that these associations may be attributable to heightened sexual reward sensitivity among adversity-exposed women. We aimed to test these claims using a combination of self-report and EEG measures to test the relationship between early adversity, sexual reward sensitivity (both self-reported and EEG measured) and sexual risk taking in a sexually diverse sample of cis-gender women (N = 208) (Mage = 27.17, SD = 6.36). Results showed that childhood SES predicted self-reported sexual reward sensitivity which in turn predicted numbers of male and female sexual partners. In contrast we found that perceived childhood unpredictability predicted neurobiological sexual reward sensitivity as measured by EEG which in turn predicted male sexual partner number. The results presented here provide support for the notion that heightened sexual reward sensitivity may be a pathway through which early life adversity augments future sexual behavior, and underscores the importance of including greater attention to the dynamics of pleasure and reward in sexual health promotion.


Assuntos
Comportamento Sexual , Parceiros Sexuais , Humanos , Masculino , Feminino , Criança , Autorrelato , Identidade de Gênero , Recompensa
2.
Soc Sci Res ; 119: 103000, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38609308

RESUMO

Studies often attribute the persistent gender pay gap to different labor force experiences between men and women. Yet, attitudes formed in earlier life stages also critically shape individual outcomes. Using longitudinal data from Taiwan, this study examines whether and how adolescents' gender attitudes are related to income in young adulthood. We test two pathways that mediate this relationship at different time points: the attitude continuity pathway from adolescence to young adulthood, hypothesized by the path-dependence theory, and the occupational pathway during young adulthood, hypothesized by the gender socialization perspective. The findings show that girls with egalitarian attitudes are rewarded, as both pathways facilitate higher income in adulthood. However, boys with egalitarian attitudes are simultaneously rewarded and penalized based on different occupational characteristics, resulting in an overall null effect. This study highlights the importance of adolescent gender attitudes and the differential consequences for men and women in the labor market.


Assuntos
Renda , Recompensa , Masculino , Humanos , Adolescente , Feminino , Adulto Jovem , Adulto , Estudos Longitudinais , Socialização
3.
J Psychopathol Clin Sci ; 133(3): 245-256, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38619460

RESUMO

As a neural indicator of reward responsiveness (RR), reward positivity (RewP) has been demonstrated to moderate the association between stress exposure and depressive symptoms. However, extant research has primarily (a) focused on life stress rather than early maltreatment, (b) ignored the time-frequency components, and (c) has been based on a traditional perspective of diathesis stress. The present study aimed to comprehensively examine whether and how neurophysiological (RewP and its time-frequency decomposition components) and self-reported measures of RR interact with childhood emotional abuse on young adult depressive symptoms. The sample of 192 Chinese university students aged 18-25 (Mage = 21.08 ± 1.91 years; 59.4% girls) completed self-reported questionnaires of emotional abuse, depressive symptoms and RR. The RewP and its time-frequency components delta and theta were elicited via a monetary reward task. The results demonstrated that RewP significantly moderated the association between emotional abuse and young adult depressive symptoms in a differential susceptibility but not diathesis-stress manner. However, gain-related delta, loss-related theta, or self-reported RR did not drive such moderation effects. These findings were robust and survived a series of rigorous sensitivity analyses. The current findings provide preliminary evidence that heightened RewP may function as a plasticity factor moderating the association between early maltreatment exposure and depression, and highlight the effect specific to emotional abuse. However, caution should be paid to the generalizability of these findings in high-risk clinical samples, in light of the current high-functioning sample features and low rates of high symptom and abuse levels. (PsycInfo Database Record (c) 2024 APA, all rights reserved).


Assuntos
Maus-Tratos Infantis , Depressão , Abuso Emocional , Recompensa , Adolescente , Adulto , Criança , Feminino , Humanos , Masculino , Adulto Jovem , Bases de Dados Factuais , Depressão/epidemiologia , População do Leste Asiático
4.
BMC Psychiatry ; 24(1): 251, 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38566048

RESUMO

BACKGROUND: The Quick Delay Questionnaire (QDQ) is a short questionnaire designed to assess delay-related difficulties in adults. This study aimed to examine the reliability and validity of the Chinese version of the QDQ (C-QDQ) in Chinese adults, and explore the ecological characteristics of delay-related impulsivity in Chinese adults with attention-deficit/hyperactivity disorder (ADHD). METHODS: Data was collected from 302 adults, including ADHD (n = 209) and healthy controls (HCs) (n = 93). All participants completed the C-QDQ. The convergent validity, internal consistency, retest reliability and confirmatory factor analysis (CFA) of the C-QDQ were analyzed. The correlations between C-QDQ and two laboratory measures of delay-related difficulties and Barratt Impulsiveness Scale-11 (BIS-11), the comparison of C-QDQ scores between ADHD subgroups and HCs were also analyzed. RESULTS: The Cronbach's α of C-QDQ was between 0.83 and 0.89. The intraclass correlation coefficient of C-QDQ was between 0.80 and 0.83. The results of CFA of C-QDQ favoured the original two-factor model (delay aversion and delay discounting). Significant positive associations were found between C-QDQ scores and BIS-11 total score and performance on the laboratory measure of delay-related difficulties. Participants with ADHD had higher C-QDQ scores than HCs, and female ADHD reported higher scores on delay discounting subscale than male. ADHD-combined type (ADHD-C) reported higher scores on delay aversion subscale than ADHD-inattention type (ADHD-I). CONCLUSION: The C-QDQ is a valid and reliable tool to measure delay-related responses that appears to have clinical utility. It can present the delay-related impulsivity of patients with ADHD. Compared to HCs, the level of reward-delay impulsivity was higher in ADHD.


Assuntos
Transtorno do Deficit de Atenção com Hiperatividade , Adulto , Humanos , Masculino , Feminino , Transtorno do Deficit de Atenção com Hiperatividade/diagnóstico , Psicometria , Reprodutibilidade dos Testes , Comportamento Impulsivo , Recompensa , Inquéritos e Questionários
5.
Elife ; 122024 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-38567902

RESUMO

Dopamine and orexins (hypocretins) play important roles in regulating reward-seeking behaviors. It is known that hypothalamic orexinergic neurons project to dopamine neurons in the ventral tegmental area (VTA), where they can stimulate dopaminergic neuronal activity. Although there are reciprocal connections between dopaminergic and orexinergic systems, whether and how dopamine regulates the activity of orexin neurons is currently not known. Here we implemented an opto-Pavlovian task in which mice learn to associate a sensory cue with optogenetic dopamine neuron stimulation to investigate the relationship between dopamine release and orexin neuron activity in the lateral hypothalamus (LH). We found that dopamine release can be evoked in LH upon optogenetic stimulation of VTA dopamine neurons and is also naturally evoked by cue presentation after opto-Pavlovian learning. Furthermore, orexin neuron activity could also be upregulated by local stimulation of dopaminergic terminals in the LH in a way that is partially dependent on dopamine D2 receptors (DRD2). Our results reveal previously unknown orexinergic coding of reward expectation and unveil an orexin-regulatory axis mediated by local dopamine inputs in the LH.


Assuntos
Região Hipotalâmica Lateral , Área Tegmentar Ventral , Camundongos , Animais , Orexinas , Área Tegmentar Ventral/fisiologia , Dopamina , Receptores de Dopamina D2 , Neurônios Dopaminérgicos , Recompensa
6.
Nat Commun ; 15(1): 2976, 2024 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-38582905

RESUMO

Natural fluctuations in cardiac activity modulate brain activity associated with sensory stimuli, as well as perceptual decisions about low magnitude, near-threshold stimuli. However, little is known about the relationship between fluctuations in heart activity and other internal representations. Here we investigate whether the cardiac cycle relates to learning-related internal representations - absolute and signed prediction errors. We combined machine learning techniques with electroencephalography with both simple, direct indices of task performance and computational model-derived indices of learning. Our results demonstrate that just as people are more sensitive to low magnitude, near-threshold sensory stimuli in certain cardiac phases, so are they more sensitive to low magnitude absolute prediction errors in the same cycles. However, this occurs even when the low magnitude prediction errors are associated with clearly suprathreshold sensory events. In addition, participants exhibiting stronger differences in their prediction error representations between cardiac cycles exhibited higher learning rates and greater task accuracy.


Assuntos
Eletroencefalografia , Recompensa , Humanos , Análise e Desempenho de Tarefas
7.
eNeuro ; 11(4)2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38569920

RESUMO

Most neuroeconomic research seeks to understand how value influences decision-making. The influence of reward type is less well understood. We used functional magnetic resonance imaging (fMRI) to investigate delay discounting of primary (i.e., food) and secondary rewards (i.e., money) in 28 healthy, normal-weighted participants (mean age = 26.77; 18 females). To decipher differences in discounting behavior between reward types, we compared how well-different option-based statistical models (exponential, hyperbolic discounting) and attribute-wise heuristic choice models (intertemporal choice heuristic, dual reasoning and implicit framework theory, trade-off model) captured the reward-specific discounting behavior. Contrary to our hypothesis of different strategies for different rewards, we observed comparable discounting behavior for money and food (i.e., exponential discounting). Higher k values for food discounting suggest that individuals decide more impulsive if confronted with food. The fMRI revealed that money discounting was associated with enhanced activity in the right dorsolateral prefrontal cortex, involved in executive control; the right dorsal striatum, associated with reward processing; and the left hippocampus, involved in memory encoding/retrieval. Food discounting, instead, was associated with higher activity in the left temporoparietal junction suggesting social reinforcement of food decisions. Although our findings do not confirm our hypothesis of different discounting strategies for different reward types, they are in line with the notion that reward types have a significant influence on impulsivity with primary rewards leading to more impulsive choices.


Assuntos
Desvalorização pelo Atraso , Feminino , Humanos , Adulto , Desvalorização pelo Atraso/fisiologia , Recompensa , Encéfalo/diagnóstico por imagem , Encéfalo/fisiologia , Comportamento Impulsivo/fisiologia , Hipocampo , Imageamento por Ressonância Magnética/métodos , Comportamento de Escolha/fisiologia
8.
Anim Cogn ; 27(1): 31, 2024 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-38592559

RESUMO

We studied how different types of social demonstration improve house sparrows' (Passer domesticus) success in solving a foraging task that requires both operant learning (opening covers) and discrimination learning (preferring covers of the rewarding colour). We provided learners with either paired demonstration (of both cover opening and colour preference), action-only demonstration (of opening white covers only), or no demonstration (a companion bird eating without covers). We found that sparrows failed to learn the two tasks with no demonstration, and learned them best with a paired demonstration. Interestingly, the action of cover opening was learned faster with paired rather than action-only demonstration despite being equally demonstrated in both. We also found that only with paired demonstration, the speed of operant (action) learning was related to the demonstrator's level of activity. Colour preference (i.e. discrimination learning) was eventually acquired by all sparrows that learned to open covers, even without social demonstration of colour preference. Thus, adding a demonstration of colour preference was actually more important for operant learning, possibly as a result of increasing the similarity between the demonstrated and the learned tasks, thereby increasing the learner's attention to the actions of the demonstrator. Giving more attention to individuals in similar settings may be an adaptive strategy directing social learners to focus on ecologically relevant behaviours and on tasks that are likely to be learned successfully.


Assuntos
Aprendizagem por Discriminação , Aprendizagem , Humanos , Animais , Cor , Recompensa
9.
PLoS One ; 19(4): e0300842, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38598429

RESUMO

Maze-solving is a classical mathematical task, and is recently analogously achieved using various eccentric media and devices, such as living tissues, chemotaxis, and memristors. Plasma generated in a labyrinth of narrow channels can also play a role as a route finder to the exit. In this study, we experimentally observe the function of maze-route findings in a plasma system based on a mixed discharge scheme of direct-current (DC) volume mode and alternative-current (AC) surface dielectric-barrier discharge, and computationally generalize this function in a reinforcement-learning model. In our plasma system, we install two electrodes at the entry and the exit in a square lattice configuration of narrow channels whose cross section is 1×1 mm2 with the total length around ten centimeters. Visible emissions in low-pressure Ar gas are observed after plasma ignition, and the plasma starting from a given entry location reaches the exit as the discharge voltage increases, whose route converging level is quantified by Shannon entropy. A similar short-path route is reproduced in a reinforcement-learning model in which electric potentials through the discharge voltage is replaced by rewards with positive and negative sign or polarity. The model is not rigorous numerical representation of plasma simulation, but it shares common points with the experiments along with a rough sketch of underlying processes (charges in experiments and rewards in modelling). This finding indicates that a plasma-channel network works in an analog computing function similar to a reinforcement-learning algorithm slightly modified in this study.


Assuntos
Líquidos Corporais , Reforço Psicológico , Recompensa , Plasma , Algoritmos
10.
Sci Rep ; 14(1): 8422, 2024 04 10.
Artigo em Inglês | MEDLINE | ID: mdl-38600089

RESUMO

Recent studies suggest that depression and anxiety are associated with unique aspects of EEG responses to reward and punishment, respectively; also, abnormal responses to punishment in depressed individuals are related to anxiety, the symptoms of which are comorbid with depression. In a non-clinical sample, we aimed to investigate the relationships between reward processing and anxiety, between punishment processing and anxiety, between reward processing and depression, and between punishment processing and depression. Towards this aim, we separated feedback-related brain activity into delta and theta bands to isolate activity that indexes functionally distinct processes. Based on the delta/theta frequency and feedback valence, we then used machine learning (ML) to classify individuals with high severity of depressive symptoms and individuals with high severity of anxiety symptoms versus controls. The significant difference between the depression and control groups was driven mainly by delta activity; there were no differences between reward- and punishment-theta activities. The high severity of anxiety symptoms was marginally more strongly associated with the punishment- than the reward-theta feedback processing. The findings provide new insights into the differences in the impacts of anxiety and depression on reward and punishment processing; our study shows the utility of ML in testing brain-behavior hypotheses and emphasizes the joint effect of theta-RewP/FRN and delta frequency on feedback-related brain activity.


Assuntos
Depressão , Eletroencefalografia , Humanos , Punição , Ansiedade , Recompensa , Potenciais Evocados/fisiologia
11.
PLoS One ; 19(4): e0299511, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38626247

RESUMO

Delay discounting is a phenomenon strongly associated with impulsivity. However, in order for a measured discounting rate in an experiment to meaningfully generalize to choices made elsewhere in life, participants must provide thoughtful, engaged answers during the assessment. Classic discounting tasks may not optimize intrinsic motivation or enjoyment, and a participant who is disengaged from the task is likely to behave in a way that provides a biased estimate of their discounting function. We assessed degree of delay discounting in a task intended to vary level of participant motivation. This was accomplished by introducing varying levels of gamification, the application of game design principles to a non-game context. Experiment 1 compared three versions of the delay discounting task with differing degrees of gamification and compared performance and task enjoyment across those variations, while Experiment 2 used two conditions (one gamified, one not). Participants found more gamified versions of the task more enjoyable than the other conditions, without producing substantial between-group differences in most cases. Thus, more polished task gameplay can provide a more enjoyable experience for participants without undermining delay discounting effects commonly reported in the literature. We also found that in all experimental conditions, higher levels of interest in or enjoyment of the task tended to be associated with more rapid discounting. This may suggest that low task motivation may result in less impulsive choice and suggests that participants who find delay discounting experiments sufficiently boring may bias assessments of value across delays.


Assuntos
Desvalorização pelo Atraso , Humanos , Gamificação , Comportamento Impulsivo , Motivação , Felicidade , Recompensa , Comportamento de Escolha
12.
eNeuro ; 11(4)2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38565297

RESUMO

In many real-life scenarios, our decisions could lead to multiple outcomes that conflict with value. Hence, an appropriate neural representation of the net experienced value of conflicting outcomes, which play a crucial role in guiding future decisions, is critical for adaptive behavior. As some recent functional neuroimaging work has primarily focused on the concurrent processing of monetary gains and aversive information, very little is known regarding the integration of conflicting value signals involving monetary losses and appetitive information in the human brain. To address this critical gap, we conducted a functional MRI study involving healthy human male participants to examine the nature of integrating positive emotion and monetary losses. We employed a novel experimental design where the valence (positive or neutral) of an emotional stimulus indicated the type of outcome (loss or no loss) in a choice task. Specifically, we probed two plausible integration patterns while processing conflicting value signals involving positive emotion and monetary losses: interactive versus additive. We found overlapping main effects of positive (vs neutral) emotion and loss (vs no loss) in multiple brain regions, including the ventromedial prefrontal cortex, striatum, and amygdala, notably with a lack of evidence for interaction. Thus, our findings revealed the additive integration pattern of monetary loss and positive emotion outcomes, suggesting that the experienced value of the monetary loss was not modulated by the valence of the image signaling those outcomes. These findings contribute to our limited understanding of the nature of integrating conflicting outcomes in the healthy human brain with potential clinical relevance.


Assuntos
Encéfalo , Emoções , Humanos , Masculino , Tonsila do Cerebelo , Córtex Pré-Frontal , Mapeamento Encefálico , Imageamento por Ressonância Magnética/métodos , Recompensa
13.
Dev Psychobiol ; 66(4): e22495, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38643359

RESUMO

Most studies of adolescent and adult behavior involved one age group of each, whereas the dynamic changes in brain development suggest that there may be behavioral flux in adolescence. In two studies, we investigated developmental changes in social reward motivation in female and male Long-Evans rats from prepuberty to early adulthood in a social operant conditioning task. Given the earlier onset of puberty in females than in males, we predicted the course of social reward development would differ between the sexes. Overall, the pattern of results from both studies suggests that the trajectory of social motivation across adolescence is characterized by upward and downward shifts that do not depend on the sex of the rats. During training, in both studies, the mean number of social gate openings and percentage of social gate openings was higher at P30 (prepubertal, early adolescence) and P50 (late adolescence) than at P40 (mid adolescence) and P70 (adulthood) irrespective of sex. Nevertheless, the specific age comparisons that were significant depended on the study. In both studies, P30 rats had greater levels of social motivation than did adults in accessing a social reward when increased effort was required (progressive ratio tests). In an extinction test, only P30 and P50 rats continued to show more nose-pokes at the previously social gate than at the nonsocial gate, suggesting resistance to extinction. The results highlight the importance of characterizing behavior at several timepoints in adolescence to understand the neural mechanisms, many of which show similar discontinuities as they develop across adolescence.


Assuntos
Motivação , Maturidade Sexual , Masculino , Ratos , Feminino , Animais , Ratos Long-Evans , Recompensa , Condicionamento Operante
14.
PLoS One ; 19(4): e0301539, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38574098

RESUMO

Aberrant reward processing and poor self-regulation have a crucial role in the development of several adverse outcomes in youth, including mental health disorders and risky behaviours. This scoping review aims to map and summarise the evidence for links between aspects and measures of reward processing and self-regulation among children and adolescents in the general population. Specifically, it examined the direct associations between self-regulation (emotional or cognitive regulation) and reward processing. Studies were included if participants were <18 years and representative of the general population. Quantitative measures were used for self-regulation, and gambling tasks were used for reward processing. Of the eighteen studies included only two were longitudinal. Overall, the direction of the significant relationships identified depended on the gambling task used and the self-regulation aspect explored. Emotional regulation was measured with self-report questionnaires only, and was the aspect with the most significant associations. Conversely, cognitive regulation was mainly assessed with cognitive assessments, and most associations with reward processing were non-significant, particularly when the cognitive regulation aspects included planning and organisational skills. Nonetheless, there was some evidence of associations with attention, cognitive control, and overall executive functioning. More longitudinal research is needed to draw accurate conclusions on the direction of the association between self-regulation and reward processing.


Assuntos
Jogo de Azar , Autocontrole , Criança , Humanos , Adolescente , Jogo de Azar/psicologia , Função Executiva , Atenção , Recompensa
15.
PLoS One ; 19(4): e0301781, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38578791

RESUMO

Our mental representation of the passage of time is structured by concepts of spatial motion, including an ego-moving perspective in which the self is perceived as approaching future events and a time-moving perspective in which future events are perceived as approaching the self. While previous research has found that processing spatial information in one's environment can preferentially activate either an ego-moving or time-moving temporal perspective, potential downstream impacts on everyday decision-making have received less empirical attention. Based on the idea people may feel closer to positive events they see themselves as actively approaching rather than passively waiting for, in this pre-registered study we tested the hypothesis that spatial primes corresponding to an ego-moving (vs. time-moving) perspective would attenuate temporal discounting by making future rewards feel more proximal. 599 participants were randomly assigned to one of three spatial prime conditions (ego-moving, time-moving, control) resembling map-based tasks people may engage with on digital devices, before completing measures of temporal perspective, perceived wait time, perceived control over time, and temporal discounting. Partly consistent with previous research, the results indicated that the time-moving prime successfully activated the intended temporal perspective-though the ego-moving prime did not. Contrary to our primary hypotheses, the spatial primes had no effect on either perceived wait time or temporal discounting. Processing spatial information in a map-based task therefore appears to influence how people conceptualise the passage of time, but there was no evidence for downstream effects on intertemporal preferences. Additionally, exploratory analysis indicated that greater perceived control over time was associated with lower temporal discounting, mediated by a reduction in perceived wait time, suggesting a possible area for future research into individual differences and interventions in intertemporal decision-making.


Assuntos
Desvalorização pelo Atraso , Percepção do Tempo , Humanos , Recompensa , Desvalorização pelo Atraso/fisiologia , Percepção do Tempo/fisiologia , Emoções , Individualidade
16.
Nat Commun ; 15(1): 2948, 2024 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-38580626

RESUMO

Intertemporal choices - decisions that play out over time - pervade our life. Thus, how people make intertemporal choices is a fundamental question. Here, we investigate the role of attribute latency (the time between when people start to process different attributes) in shaping intertemporal preferences using five experiments with choices between smaller-sooner and larger-later rewards. In the first experiment, we identify attribute latencies using mouse-trajectories and find that they predict individual differences in choices, response times, and changes across time constraints. In the other four experiments we test the causal link from attribute latencies to choice, staggering the display of the attributes. This changes attribute latencies and intertemporal preferences. Displaying the amount information first makes people more patient, while displaying time information first does the opposite. These findings highlight the importance of intra-choice dynamics in shaping intertemporal choices and suggest that manipulating attribute latency may be a useful technique for nudging.


Assuntos
Desvalorização pelo Atraso , Humanos , Animais , Camundongos , Fatores de Tempo , Recompensa , Tempo de Reação , Comportamento de Escolha/fisiologia
17.
Chaos ; 34(3)2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38442233

RESUMO

Vaccination is the most effective way to control the epidemic spreading. However, the probability of people getting vaccinated changes with the epidemic situation due to personal psychology. Facing various risks, some people are reluctant to vaccinate and even prefer herd immunity. To encourage people to get vaccinated, many countries set up reward mechanisms. In this paper, we propose a disease transmission model combining vaccination behaviors based on the SIR (Susceptible-Infected-Recovered) model and introduce three vaccination mechanisms. We analyze the impact of the infection rate and the recovery rate on the total cost and the epidemic prevalence. Numerical simulations fit with our intuitive feelings. Then, we study the impact of vaccination rewards on the total social cost. We find that when vaccination rewards offset vaccination costs, both the total cost and the epidemic prevalence reach the lowest levels. Finally, this paper suggests that encouraging people to get vaccinated at the beginning of an epidemic has the best effect.


Assuntos
Emoções , Epidemias , Humanos , Recompensa , Vacinação , Percepção
18.
Neuroimage ; 290: 120574, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38467346

RESUMO

Obesity has a profound impact on metabolic health thereby adversely affecting brain structure and function. However, the majority of previous studies used a single structural index to investigate the link between brain structure and body mass index (BMI), which hinders our understanding of structural covariance between regions in obesity. This study aimed to examine the relationship between macroscale cortical organization and BMI using novel morphometric similarity networks (MSNs). The individual MSNs were first constructed from individual eight multimodal cortical morphometric features between brain regions. Then the relationship between BMI and MSNs within the discovery sample of 434 participants was assessed. The key findings were further validated in an independent sample of 192 participants. We observed that the lateral non-reward orbitofrontal cortex (lOFC) exhibited decoupling (i.e., reduction in integration) in obesity, which was mainly manifested by its decoupling with the cognitive systems (i.e., DMN and FPN) while the medial reward orbitofrontal cortex (mOFC) showed de-differentiation (i.e., decrease in distinctiveness) in obesity, which was mainly represented by its de-differentiation with the cognitive and attention systems (i.e., DMN and VAN). Additionally, the lOFC showed de-differentiation with the visual system in obesity, while the mOFC showed decoupling with the visual system and hyper-coupling with the sensory-motor system in obesity. As an important first step in revealing the role of underlying structural covariance in body mass variability, the present study presents a novel mechanism that underlies the reward-control interaction imbalance in obesity, thus can inform future weight-management approaches.


Assuntos
Córtex Pré-Frontal , Recompensa , Humanos , Córtex Pré-Frontal/diagnóstico por imagem , Lobo Frontal/diagnóstico por imagem , Encéfalo , Obesidade
19.
Nature ; 627(8004): 572-578, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38448580

RESUMO

Culture refers to behaviours that are socially learned and persist within a population over time. Increasing evidence suggests that animal culture can, like human culture, be cumulative: characterized by sequential innovations that build on previous ones1. However, human cumulative culture involves behaviours so complex that they lie beyond the capacity of any individual to independently discover during their lifetime1-3. To our knowledge, no study has so far demonstrated this phenomenon in an invertebrate. Here we show that bumblebees can learn from trained demonstrator bees to open a novel two-step puzzle box to obtain food rewards, even though they fail to do so independently. Experimenters were unable to train demonstrator bees to perform the unrewarded first step without providing a temporary reward linked to this action, which was removed during later stages of training. However, a third of naive observer bees learned to open the two-step box from these demonstrators, without ever being rewarded after the first step. This suggests that social learning might permit the acquisition of behaviours too complex to 're-innovate' through individual learning. Furthermore, naive bees failed to open the box despite extended exposure for up to 24 days. This finding challenges a common opinion in the field: that the capacity to socially learn behaviours that cannot be innovated through individual trial and error is unique to humans.


Assuntos
Abelhas , Comportamento Animal , Alimentos , Conhecimento , Aprendizagem , Recompensa , Comportamento Social , Animais , Humanos , Abelhas/fisiologia , Cultura , Ensino
20.
Ann Behav Med ; 58(5): 341-352, 2024 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-38507617

RESUMO

BACKGROUND: Delay discounting is the depreciation in a reward's perceived value as a function of the time until receipt. Monetary incentive programs that provide rewards contingent on meeting daily physical activity (PA) goals may change participants' delay discounting preferences. PURPOSE: Determine if monetary incentives provided in close temporal proximity to meeting PA goals changed delay discounting, and if such changes mediated intervention effects. METHODS: Inactive adults (n = 512) wore accelerometers during a 12-month intervention where they received proximal monetary incentives for meeting daily moderate-to-vigorous PA (MVPA) goals or delayed incentives for study participation. Delay discount rate and average MVPA were assessed at baseline, end of intervention, and a 24-month follow-up. Using structural equation modeling, we tested effects of proximal versus delayed rewards on delay discounting and whether any changes mediated intervention effects on MVPA. PA self-efficacy was also evaluated as a potential mediator, and both self-efficacy and delay discounting were assessed as potential moderators of intervention effects. RESULTS: Proximal rewards significantly increased participants' delay discounting (ß = 0.238, confidence interval [CI]: -0.078, 0.380), indicating greater sensitivity to reinforcement timing. This change did not mediate incentive-associated increases in MVPA at the end of the 12-month intervention (ß = -0.016, CI: -0.053, 0.019) or at a 24-month follow-up (ß = -0.020, CI: -0.059, 0.018). Moderation effects were not found. CONCLUSIONS: Incentive-induced increases in delay discounting did not deleteriously impact MVPA. This finding may help assuage concerns about using monetary incentives for PA promotion, but further research regarding the consequences of changes in delay discounting is warranted.


This study examined the effects of providing proximal monetary incentives for meeting daily exercise goals on people's tendency to value immediate versus delayed rewards. Inactive adults (n = 512) participated in a year-long program where they wore an accelerometer each day and received either (i) small monetary rewards in close temporal proximity to instances of meeting daily exercise goals or (ii) larger rewards at 2-month intervals for ongoing participation. Those receiving proximal incentives showed an increased preference for immediate rewards, yet this reported change did not compromise long-term physical activity gains. In a comparison analysis, we found that proximal monetary incentives were not associated with changes in exercise self-efficacy. Overall, the findings suggest that monetary incentives for exercise do not negatively impact people's activity levels, though more research is needed to fully understand the implications of changes in reward timing preferences.


Assuntos
Desvalorização pelo Atraso , Motivação , Adulto , Humanos , Recompensa , Exercício Físico
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