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1.
Annu Int Conf IEEE Eng Med Biol Soc ; 2020: 2548-2551, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-33018526

RESUMO

People make decisions multiple times on a daily basis. However, some decisions are easier to make than others and perhaps require more attention to ensure a positive outcome. During gambling, one should attempt to compute the expected rewards and risks associated with decisions. Failing to allocate attention and neural resources to estimate these values can be costly, and in some cases can lead to bankruptcy. Alpha-band (8-12 Hz) oscillatory power in the brain is thought to reflect attention, but how this influences financial decision making is not well understood. Using local field potential recordings in nine human subjects performing a gambling task, we compared alpha-band power from the cingulate cortex (CC) during trials of low and high attention. We found that alpha-band power tended to be higher during a 2 second window after a fixation cue was shown in low attention trials.


Assuntos
Jogo de Azar , Giro do Cíngulo , Encéfalo , Mapeamento Encefálico , Humanos , Recompensa
2.
Annu Int Conf IEEE Eng Med Biol Soc ; 2020: 3086-3089, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-33018657

RESUMO

Brain-Machine Interface (BMI) provides a promising way to help disabled people restore their motor functions. The patients are able to control the external devices directly from their neural signals by the decoder. Due to various reasons such as mental fatigue and distraction, the distribution of the neural signals might change, which might lead to poor performance for the decoder. In this case, we need to calibrate the parameters before each session, which needs the professionals to label the data and is not convenient for the patient's usage at home. In this paper, we propose a covariant cluster transfer mechanism for the kernel reinforcement learning (RL) algorithm to speed up the adaptation across sessions. The parameters of the decoder will adaptively change according to a reward signal, which could be easily set by the patient. More importantly, we cluster the neural patterns in previous sessions. The cluster represents the conditional distribution from neural patterns to actions. When a distinct neural pattern appears in the new session, the nearest cluster will be transferred. In this way, the knowledge from the old session could be utilized to accelerate the learning in the new session. Our proposed algorithm is tested on the simulated neural data where the neural signal's distribution differs across sessions. Compared with the training from random initialization and a weight transfer policy, our proposed cluster transfer mechanism maintains a significantly higher success rate and a faster adaptation when the conditional distribution from neural signals to actions remains similar.


Assuntos
Interfaces Cérebro-Computador , Algoritmos , Humanos , Aprendizagem , Reforço Psicológico , Recompensa
3.
Annu Int Conf IEEE Eng Med Biol Soc ; 2020: 3351-3354, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-33018722

RESUMO

Reinforcement learning (RL) algorithm interprets neural signals into movement intentions with the guidance of the reward in Brain-machine interfaces (BMIs). Current RL algorithms generally work for the tasks with immediate rewards delivery, and lack of efficiency in delayed reward task. Prefrontal cortex, including medial prefrontal cortex(mPFC), has been demonstrated to assign credit to intermediate steps, which reinforces preceding action more efficiently. In this paper, we propose to simulate the functionality of mPFC activities as intermediate rewards to train a RL based decoder in a two-step movement task. A support vector machine (SVM) is adopted to verify if the subject expects a reward due to the accomplishment of a subtask from mPFC activity. Then this discrimination result will be utilized to guide the training of the RL decoder for each step respectively. Here, we apply the Sarsa-style attention-gated reinforcement learning (SAGREL) as the decoder to interpret motor cortex(M1) activity to action states. We test on in vivo primary motor cortex (M1) and mPFC data collected from rats, where the rats need to first trigger the start and then press lever for rewards using M1 signals. SAGREL using intermediate rewards from mPFC activities achieves a prediction accuracy of 66.8% ± 2.0.% (mean ± std) %, which is significantly better than the one using the reward by the end of trial (45.9.% ± 1.2%). This reveals the potentials of modelling mPFC activities as intermediate rewards for the delayed reward tasks.


Assuntos
Interfaces Cérebro-Computador , Animais , Aprendizagem , Córtex Pré-Frontal , Ratos , Reforço Psicológico , Recompensa
4.
Nat Commun ; 11(1): 4448, 2020 09 07.
Artigo em Inglês | MEDLINE | ID: mdl-32895370

RESUMO

Substance abuse disorders are linked to alteration of circadian rhythms, although the molecular and neuronal pathways implicated have not been fully elucidated. Addictive drugs, such as cocaine, induce a rapid increase of dopamine levels in the brain. Here, we show that acute administration of cocaine triggers reprogramming in circadian gene expression in the striatum, an area involved in psychomotor and rewarding effects of drugs. This process involves the activation of peroxisome protein activator receptor gamma (PPARγ), a nuclear receptor involved in inflammatory responses. PPARγ reprogramming is altered in mice with cell-specific ablation of the dopamine D2 receptor (D2R) in the striatal medium spiny neurons (MSNs) (iMSN-D2RKO). Administration of a specific PPARγ agonist in iMSN-D2RKO mice elicits substantial rescue of cocaine-dependent control of circadian genes. These findings have potential implications for development of strategies to treat substance abuse disorders.


Assuntos
Relógios Circadianos/efeitos dos fármacos , Transtornos Relacionados ao Uso de Cocaína/fisiopatologia , Cocaína/efeitos adversos , Núcleo Accumbens/efeitos dos fármacos , PPAR gama/metabolismo , Receptores de Dopamina D2/metabolismo , Administração Oral , Animais , Relógios Circadianos/fisiologia , Cocaína/administração & dosagem , Transtornos Relacionados ao Uso de Cocaína/tratamento farmacológico , Dopamina/metabolismo , Injeções Intraperitoneais , Locomoção/fisiologia , Masculino , Camundongos , Camundongos Knockout , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Núcleo Accumbens/fisiopatologia , PPAR gama/agonistas , Pioglitazona/administração & dosagem , Receptores de Dopamina D2/genética , Recompensa , Transdução de Sinais
5.
Nat Commun ; 11(1): 4217, 2020 08 31.
Artigo em Inglês | MEDLINE | ID: mdl-32868778

RESUMO

The cerebellum plays a crucial role in sensorimotor and associative learning. However, the contribution of molecular layer interneurons (MLIs) to these processes is not well understood. We used two-photon microscopy to study the role of ensembles of cerebellar MLIs in a go-no go task where mice obtain a sugar water reward if they lick a spout in the presence of the rewarded odorant and avoid a timeout when they refrain from licking for the unrewarded odorant. In naive animals the MLI responses did not differ between the odorants. With learning, the rewarded odorant elicited a large increase in MLI calcium responses, and the identity of the odorant could be decoded from the differential response. Importantly, MLIs switched odorant responses when the valence of the stimuli was reversed. Finally, mice took a longer time to refrain from licking in the presence of the unrewarded odorant and had difficulty becoming proficient when MLIs were inhibited by chemogenetic intervention. Our findings support a role for MLIs in learning valence in the cerebellum.


Assuntos
Cerebelo/fisiologia , Condicionamento Operante/fisiologia , Interneurônios/fisiologia , Aprendizagem/fisiologia , Células de Purkinje/fisiologia , Algoritmos , Animais , Cerebelo/citologia , Feminino , Masculino , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Microscopia de Fluorescência por Excitação Multifotônica , Modelos Neurológicos , Odorantes , Recompensa , Fatores de Tempo
6.
Nat Commun ; 11(1): 4669, 2020 09 16.
Artigo em Inglês | MEDLINE | ID: mdl-32938940

RESUMO

The prefrontal cortex and striatum form a recurrent network whose spiking activity encodes multiple types of learning-relevant information. This spike-encoded information is evident in average firing rates, but finer temporal coding might allow multiplexing and enhanced readout across the connected network. We tested this hypothesis in the fronto-striatal network of nonhuman primates during reversal learning of feature values. We found that populations of neurons encoding choice outcomes, outcome prediction errors, and outcome history in their firing rates also carry significant information in their phase-of-firing at a 10-25 Hz band-limited beta frequency at which they synchronize across lateral prefrontal cortex, anterior cingulate cortex and anterior striatum when outcomes were processed. The phase-of-firing code exceeds information that can be obtained from firing rates alone and is evident for inter-areal connections between anterior cingulate cortex, lateral prefrontal cortex and anterior striatum. For the majority of connections, the phase-of-firing information gain is maximal at phases of the beta cycle that were offset from the preferred spiking phase of neurons. Taken together, these findings document enhanced information of three important learning variables at specific phases of firing in the beta cycle at an inter-areally shared beta oscillation frequency during goal-directed behavior.


Assuntos
Corpo Estriado/fisiologia , Giro do Cíngulo/fisiologia , Aprendizagem/fisiologia , Neurônios/fisiologia , Córtex Pré-Frontal/fisiologia , Animais , Análise por Conglomerados , Corpo Estriado/citologia , Sincronização de Fases em Eletroencefalografia , Eletrofisiologia/métodos , Eletrofisiologia/estatística & dados numéricos , Giro do Cíngulo/citologia , Macaca mulatta , Masculino , Rede Nervosa , Córtex Pré-Frontal/citologia , Recompensa
7.
PLoS One ; 15(9): e0237914, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32886684

RESUMO

Factors beyond a person's control, such as demographic characteristics at birth, often influence the availability of rewards an individual can expect for their efforts. We know surprisingly little how such differences in opportunities impact human motivation. To test this, we designed a study in which we arbitrarily varied the reward offered to each participant in a group for performing the same task. Participants then had to decide whether or not they were willing to exert effort to receive their reward. Across three experiments, we found that the unequal distribution of offers reduced participants' motivation to pursue rewards even when their relative position in the distribution was high, and despite the decision being of no benefit to others and reducing the reward for oneself. Participants' feelings partially mediated this relationship. In particular, a large disparity in rewards was associated with greater unhappiness, which was associated with lower willingness to work-even when controlling for absolute reward and its relative value, both of which also affected decisions to work. A model that incorporated a person's relative position and unfairness of rewards in the group fit better to the data than other popular models describing the effects of inequality. Our findings suggest opportunity-gaps can trigger psychological dynamics that hurt productivity and well-being of all involved.


Assuntos
Motivação , Fatores Socioeconômicos , Adolescente , Adulto , Comportamento , Emoções , Feminino , Humanos , Masculino , Recompensa , Análise e Desempenho de Tarefas , Adulto Jovem
8.
PLoS Comput Biol ; 16(9): e1008149, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32903264

RESUMO

Learning and generalization in spatial domains is often thought to rely on a "cognitive map", representing relationships between spatial locations. Recent research suggests that this same neural machinery is also recruited for reasoning about more abstract, conceptual forms of knowledge. Yet, to what extent do spatial and conceptual reasoning share common computational principles, and what are the implications for behavior? Using a within-subject design we studied how participants used spatial or conceptual distances to generalize and search for correlated rewards in successive multi-armed bandit tasks. Participant behavior indicated sensitivity to both spatial and conceptual distance, and was best captured using a Bayesian model of generalization that formalized distance-dependent generalization and uncertainty-guided exploration as a Gaussian Process regression with a radial basis function kernel. The same Gaussian Process model best captured human search decisions and judgments in both domains, and could simulate realistic learning curves, where we found equivalent levels of generalization in spatial and conceptual tasks. At the same time, we also find characteristic differences between domains. Relative to the spatial domain, participants showed reduced levels of uncertainty-directed exploration and increased levels of random exploration in the conceptual domain. Participants also displayed a one-directional transfer effect, where experience in the spatial task boosted performance in the conceptual task, but not vice versa. While confidence judgments indicated that participants were sensitive to the uncertainty of their knowledge in both tasks, they did not or could not leverage their estimates of uncertainty to guide exploration in the conceptual task. These results support the notion that value-guided learning and generalization recruit cognitive-map dependent computational mechanisms in spatial and conceptual domains. Yet both behavioral and model-based analyses suggest domain specific differences in how these representations map onto actions.


Assuntos
Tomada de Decisões/fisiologia , Aprendizagem/fisiologia , Modelos Psicológicos , Adulto , Algoritmos , Teorema de Bayes , Biologia Computacional , Feminino , Humanos , Masculino , Recompensa , Incerteza
9.
PLoS One ; 15(9): e0236544, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32941442

RESUMO

A team contest entails both public good characteristics within the teams as well as a contest across teams. In an experimental study, we analyse behaviour in such a team contest when allowing to punish or to reward other team members. Moreover, we compare two types of contest environment: One in which two teams compete for a prize and another one in which we switch off the between-group element of the contest. We find that reward giving, as opposed to punishing, induces higher contributions to the team contest. Furthermore, expenditures on rewarding other co-players are significantly higher than those for punishing.


Assuntos
Comportamento Competitivo , Comportamento Cooperativo , Modelos Psicológicos , Punição , Recompensa , Processos Grupais , Humanos
10.
Cochrane Database Syst Rev ; 9: CD007668, 2020 09 03.
Artigo em Inglês | MEDLINE | ID: mdl-32880104

RESUMO

BACKGROUND: Antisocial personality disorder (AsPD) is associated with poor mental health, criminality, substance use and relationship difficulties. This review updates Gibbon 2010 (previous version of the review). OBJECTIVES: To evaluate the potential benefits and adverse effects of psychological interventions for adults with AsPD. SEARCH METHODS: We searched CENTRAL, MEDLINE, Embase, 13 other databases and two trials registers up to 5 September 2019. We also searched reference lists and contacted study authors to identify studies. SELECTION CRITERIA: Randomised controlled trials of adults, where participants with an AsPD or dissocial personality disorder diagnosis comprised at least 75% of the sample randomly allocated to receive a psychological intervention, treatment-as-usual (TAU), waiting list or no treatment. The primary outcomes were aggression, reconviction, global state/functioning, social functioning and adverse events. DATA COLLECTION AND ANALYSIS: We used standard methodological procedures expected by Cochrane. MAIN RESULTS: This review includes 19 studies (eight new to this update), comparing a psychological intervention against TAU (also called 'standard Maintenance'(SM) in some studies). Eight of the 18 psychological interventions reported data on our primary outcomes. Four studies focussed exclusively on participants with AsPD, and 15 on subgroups of participants with AsPD. Data were available from only 10 studies involving 605 participants. Eight studies were conducted in the UK and North America, and one each in Iran, Denmark and the Netherlands. Study duration ranged from 4 to 156 weeks (median = 26 weeks). Most participants (75%) were male; the mean age was 35.5 years. Eleven studies (58%) were funded by research councils. Risk of bias was high for 13% of criteria, unclear for 54% and low for 33%. Cognitive behaviour therapy (CBT) + TAU versus TAU One study (52 participants) found no evidence of a difference between CBT + TAU and TAU for physical aggression (odds ratio (OR) 0.92, 95% CI 0.28 to 3.07; low-certainty evidence) for outpatients at 12 months post-intervention. One study (39 participants) found no evidence of a difference between CBT + TAU and TAU for social functioning (mean difference (MD) -1.60 points, 95% CI -5.21 to 2.01; very low-certainty evidence), measured by the Social Functioning Questionnaire (SFQ; range = 0-24), for outpatients at 12 months post-intervention. Impulsive lifestyle counselling (ILC) + TAU versus TAU One study (118 participants) found no evidence of a difference between ILC + TAU and TAU for trait aggression (assessed with Buss-Perry Aggression Questionnaire-Short Form) for outpatients at nine months (MD 0.07, CI -0.35 to 0.49; very low-certainty evidence). One study (142 participants) found no evidence of a difference between ILC + TAU and TAU alone for the adverse event of death (OR 0.40, 95% CI 0.04 to 4.54; very low-certainty evidence) or incarceration (OR 0.70, 95% CI 0.27 to 1.86; very low-certainty evidence) for outpatients between three and nine months follow-up. Contingency management (CM) + SM versus SM One study (83 participants) found evidence that, compared to SM alone, CM + SM may improve social functioning measured by family/social scores on the Addiction Severity Index (ASI; range = 0 (no problems) to 1 (severe problems); MD -0.08, 95% CI -0.14 to -0.02; low-certainty evidence) for outpatients at six months. 'Driving whilst intoxicated' programme (DWI) + incarceration versus incarceration One study (52 participants) found no evidence of a difference between DWI + incarceration and incarceration alone on reconviction rates (hazard ratio 0.56, CI -0.19 to 1.31; very low-certainty evidence) for prisoner participants at 24 months. Schema therapy (ST) versus TAU One study (30 participants in a secure psychiatric hospital, 87% had AsPD diagnosis) found no evidence of a difference between ST and TAU for the number of participants who were reconvicted (OR 2.81, 95% CI 0.11 to 74.56, P = 0.54) at three years. The same study found that ST may be more likely to improve social functioning (assessed by the mean number of days until patients gain unsupervised leave (MD -137.33, 95% CI -271.31 to -3.35) compared to TAU, and no evidence of a difference between the groups for overall adverse events, classified as the number of people experiencing a global negative outcome over a three-year period (OR 0.42, 95% CI 0.08 to 2.19). The certainty of the evidence for all outcomes was very low. Social problem-solving (SPS) + psychoeducation (PE) versus TAU One study (17 participants) found no evidence of a difference between SPS + PE and TAU for participants' level of social functioning (MD -1.60 points, 95% CI -5.43 to 2.23; very low-certainty evidence) assessed with the SFQ at six months post-intervention. Dialectical behaviour therapy versus TAU One study (skewed data, 14 participants) provided very low-certainty, narrative evidence that DBT may reduce the number of self-harm days for outpatients at two months post-intervention compared to TAU. Psychosocial risk management (PSRM; 'Resettle') versus TAU One study (skewed data, 35 participants) found no evidence of a difference between PSRM and TAU for a number of officially recorded offences at one year after release from prison. It also found no evidence of difference between the PSRM and TAU for the adverse event of death during the study period (OR 0.89, 95% CI 0.05 to 14.83, P = 0.94, 72 participants (90% had AsPD), 1 study, very low-certainty evidence). AUTHORS' CONCLUSIONS: There is very limited evidence available on psychological interventions for adults with AsPD. Few interventions addressed the primary outcomes of this review and, of the eight that did, only three (CM + SM, ST and DBT) showed evidence that the intervention may be more effective than the control condition. No intervention reported compelling evidence of change in antisocial behaviour. Overall, the certainty of the evidence was low or very low, meaning that we have little confidence in the effect estimates reported. The conclusions of this update have not changed from those of the original review, despite the addition of eight new studies. This highlights the ongoing need for further methodologically rigorous studies to yield further data to guide the development and application of psychological interventions for AsPD and may suggest that a new approach is required.


Assuntos
Transtorno da Personalidade Antissocial/terapia , Psicoterapia/métodos , Adulto , Agressão/psicologia , Transtorno da Personalidade Antissocial/mortalidade , Transtornos Relacionados ao Uso de Cocaína/terapia , Terapia Cognitivo-Comportamental/métodos , Dirigir sob a Influência , Feminino , Humanos , Masculino , Prisioneiros/estatística & dados numéricos , Ensaios Clínicos Controlados Aleatórios como Assunto , Reincidência/estatística & dados numéricos , Recompensa , Resultado do Tratamento
11.
Nat Commun ; 11(1): 4715, 2020 09 18.
Artigo em Inglês | MEDLINE | ID: mdl-32948772

RESUMO

Animal-fMRI is a powerful method to understand neural mechanisms of cognition, but it remains a major challenge to scan actively participating small animals under low-stress conditions. Here, we present an event-related functional MRI platform in awake pigeons using single-shot RARE fMRI to investigate the neural fundaments for visually-guided decision making. We established a head-fixated Go/NoGo paradigm, which the animals quickly learned under low-stress conditions. The animals were motivated by water reward and behavior was assessed by logging mandibulations during the fMRI experiment with close to zero motion artifacts over hundreds of repeats. To achieve optimal results, we characterized the species-specific hemodynamic response function. As a proof-of-principle, we run a color discrimination task and discovered differential neural networks for Go-, NoGo-, and response execution-phases. Our findings open the door to visualize the neural fundaments of perceptual and cognitive functions in birds-a vertebrate class of which some clades are cognitively on par with primates.


Assuntos
Encéfalo/diagnóstico por imagem , Encéfalo/fisiologia , Cognição/fisiologia , Imagem por Ressonância Magnética/métodos , Imagem por Ressonância Magnética/veterinária , Vigília , Animais , Artefatos , Comportamento Animal/fisiologia , Mapeamento Encefálico , Columbidae , Humanos , Inibição Psicológica , Aprendizagem , Movimento (Física) , Redes Neurais de Computação , Recompensa
14.
Nat Commun ; 11(1): 3845, 2020 07 31.
Artigo em Inglês | MEDLINE | ID: mdl-32737295

RESUMO

Many experimental studies suggest that animals can rapidly learn to identify odors and predict the rewards associated with them. However, the underlying plasticity mechanism remains elusive. In particular, it is not clear how olfactory circuits achieve rapid, data efficient learning with local synaptic plasticity. Here, we formulate olfactory learning as a Bayesian optimization process, then map the learning rules into a computational model of the mammalian olfactory circuit. The model is capable of odor identification from a small number of observations, while reproducing cellular plasticity commonly observed during development. We extend the framework to reward-based learning, and show that the circuit is able to rapidly learn odor-reward association with a plausible neural architecture. These results deepen our theoretical understanding of unsupervised learning in the mammalian brain.


Assuntos
Condicionamento Clássico/fisiologia , Rede Nervosa , Plasticidade Neuronal/fisiologia , Condutos Olfatórios/fisiologia , Percepção Olfatória/fisiologia , Olfato/fisiologia , Animais , Teorema de Bayes , Simulação por Computador , Mamíferos , Neurônios/citologia , Neurônios/fisiologia , Odorantes/análise , Bulbo Olfatório/fisiologia , Recompensa
15.
PLoS Biol ; 18(8): e3000800, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32776945

RESUMO

Studies of neural processes underlying delay of gratification usually focus on prefrontal networks related to curbing affective impulses. Here, we provide evidence for an alternative mechanism that facilitates delaying gratification by mental orientation towards the future. Combining continuous theta-burst stimulation (cTBS) with functional neuroimaging, we tested how the right temporoparietal junction (rTPJ) facilitates processing of future events and thereby promotes delay of gratification. Participants performed an intertemporal decision task and a mental time-travel task in the MRI scanner before and after receiving cTBS over the rTPJ or the vertex (control site). rTPJ cTBS led to both stronger temporal discounting for longer delays and reduced processing of future relative to past events in the mental time-travel task. This finding suggests that the rTPJ contributes to the ability to delay gratification by facilitating mental representation of outcomes in the future. On the neural level, rTPJ cTBS led to a reduction in the extent to which connectivity of rTPJ with striatum reflected the value of delayed rewards, indicating a role of rTPJ-striatum connectivity in constructing neural representations of future rewards. Together, our findings provide evidence that the rTPJ is an integral part of a brain network that promotes delay of gratification by facilitating mental orientation to future rewards.


Assuntos
Corpo Estriado/fisiologia , Tomada de Decisões/fisiologia , Desvalorização pelo Atraso/fisiologia , Rede Nervosa/fisiologia , Lobo Parietal/fisiologia , Lobo Temporal/fisiologia , Adulto , Mapeamento Encefálico , Corpo Estriado/anatomia & histologia , Corpo Estriado/diagnóstico por imagem , Feminino , Neuroimagem Funcional , Humanos , Comportamento Impulsivo/fisiologia , Masculino , Rede Nervosa/anatomia & histologia , Rede Nervosa/diagnóstico por imagem , Lobo Parietal/anatomia & histologia , Lobo Parietal/diagnóstico por imagem , Recompensa , Lobo Temporal/anatomia & histologia , Lobo Temporal/diagnóstico por imagem , Estimulação Magnética Transcraniana
16.
PLoS One ; 15(8): e0236979, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32760110

RESUMO

The aim of this study is to identify the dynamic explicit and implicit information factors which displayed on the webpage of platforms that influence backers' investment decision-making behavior. We analyze the connections among these factors by collecting the longitudinal dataset from reward-based crowdfunding platform. Based on ELM model, we establish Fixed Estimation Panel Data Model respectively according to explicit and implicit factors and take Funding Status (crowdfunding results) as the moderating variable to observe the goal gradient effect. Results indicate that most variables in the central route affect backers' investment behavior positively, while most variables in the periphery route have a negative impact on backers' investment behavior. The Funding Status has a significant negative moderating effect on the explicit variables, and has no significant moderating effect on the implicit information variables of the project. In addition, we upgrade the econometric method used by previous scholars, which could improve the accuracy of the FE model. Furthermore, we find strong support for the herding effect in reward-based crowdfunding and the intensity tends to decrease before the funding goal draws near.


Assuntos
Crowdsourcing/economia , Investimentos em Saúde , Comunicação Persuasiva , Recompensa , Bases de Dados Factuais , Tomada de Decisões , Humanos , Internet , Funções Verossimilhança , Modelos Econômicos , Modelos Psicológicos
17.
PLoS One ; 15(8): e0237817, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32810160

RESUMO

Transitive inference (TI) is the ability to infer unknown relationships from previous information. To test TI in non-human animals, transitive responding has been examined in a TI task where non-adjacent pairs were presented after premise pair training. Some mammals, birds and paper wasps can pass TI tasks. Although previous studies showed that some fish are capable of TI in the social context, it remains unclear whether fish can pass TI task. Here, we conducted a TI task in cleaner wrasses (Labroides dimidiatus), which interact with various client fishes and conspecifics. Because they make decisions based on previous direct and indirect interactions in the context of cleaning interactions, we predicted that the ability of TI is beneficial for cleaner fish. Four tested fish were trained with four pairs of visual stimuli in a 5-term series: A-B+, B-C+, C-D+, and D-E+ (plus and minus denote rewards and non-rewards, respectively). After training, a novel pair, BD (BD test), was presented wherein the fish chose D more frequently than B. In contrast, reinforcement history did not predict the choice D. Our results suggest that cleaner fish passed the TI task, similar to mammals and birds. Although the mechanism underlying transitive responding in cleaner fish remains unclear, this work contributes to understanding cognitive abilities in fish.


Assuntos
Aprendizagem , Perciformes/fisiologia , Animais , Comportamento de Escolha , Feminino , Masculino , Recompensa
18.
Adv Exp Med Biol ; 1284: 35-41, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32852738

RESUMO

Innate behaviors often viewed as genetically predetermined behaviors. However, in the environment animals often are subjected to external stimuli conflicting with those. Thus, animals subsequently need to change those behaviors to survive and reproduce. In the brain, the reward pathway is well-known for its role to adjust behaviors according to external stimuli, or rewards. However, only recently the relationship between reward pathway and innate behavior begins to be explored. In this review, we summarize the recent data on this subject from rodent studies which suggest an important role of this crosstalk between circuits involved in reward pathway and innate behaviors. We also discuss some of the neurotransmitters and neuromodulators underlying this crosstalk and the related mechanisms.


Assuntos
Encéfalo/fisiologia , Vias Neurais , Recompensa , Animais , Dopamina , Modelos Animais , Neurotransmissores
19.
Adv Exp Med Biol ; 1284: 43-48, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32852739

RESUMO

Social behavior is a complex behavior that requires processing of sensory cues and integration of internal states. Social interaction involves two or more individuals to approach each other and engage communications. Although sensory, motivational, emotional, or reward cues may all play roles in directing the sociability and social preference during social interaction, how neural activities from different brain regions are modulated during the behavioral process of social interaction are only beginning to be studied. Multiple brain regions including prefrontal cortex, hippocampus, and amygdala contain active neurons during social interaction. This review examines the neural responses in behaving rodents during social behavior and discusses how manipulation of specific neural pathways can modulate social behavior. Neural activities during social interaction provide direct measurements about how social information is coded and are beneficial in understanding the neural mechanisms underlying social behavior.


Assuntos
Neurônios/fisiologia , Comportamento Social , Tonsila do Cerebelo/citologia , Tonsila do Cerebelo/fisiologia , Animais , Modelos Animais , Córtex Pré-Frontal/citologia , Córtex Pré-Frontal/fisiologia , Recompensa
20.
PLoS Genet ; 16(8): e1008963, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32780743

RESUMO

Long-term memory (LTM) formation depends on the conversed cAMP response element-binding protein (CREB)-dependent gene transcription followed by de novo protein synthesis. Thirsty fruit flies can be trained to associate an odor with water reward to form water-reward LTM (wLTM), which can last for over 24 hours without a significant decline. The role of de novo protein synthesis and CREB-regulated gene expression changes in neural circuits that contribute to wLTM remains unclear. Here, we show that acute inhibition of protein synthesis in the mushroom body (MB) αß or γ neurons during memory formation using a cold-sensitive ribosome-inactivating toxin disrupts wLTM. Furthermore, adult stage-specific expression of dCREB2b in αß or γ neurons also disrupts wLTM. The MB αß and γ neurons can be further classified into five different neuronal subsets including αß core, αß surface, αß posterior, γ main, and γ dorsal. We observed that the neurotransmission from αß surface and γ dorsal neuron subsets is required for wLTM retrieval, whereas the αß core, αß posterior, and γ main are dispensable. Adult stage-specific expression of dCREB2b in αß surface and γ dorsal neurons inhibits wLTM formation. In vivo calcium imaging revealed that αß surface and γ dorsal neurons form wLTM traces with different dynamic properties, and these memory traces are abolished by dCREB2b expression. Our results suggest that a small population of neurons within the MB circuits support long-term storage of water-reward memory in Drosophila.


Assuntos
Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/genética , Proteínas de Drosophila/genética , Drosophila melanogaster/genética , Memória de Longo Prazo/fisiologia , Neurônios/metabolismo , Olfato/genética , Transativadores/genética , Animais , Animais Geneticamente Modificados , Cálcio/metabolismo , Drosophila melanogaster/fisiologia , Corpos Pedunculados/fisiologia , Neurônios/fisiologia , Biossíntese de Proteínas/genética , Recompensa , Olfato/fisiologia , Transmissão Sináptica/genética , Água
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