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1.
Nat Commun ; 10(1): 4799, 2019 10 22.
Artigo em Inglês | MEDLINE | ID: mdl-31641124

RESUMO

Metabolic diseases harm brain health and cognitive functions, but whether maternal metabolic unbalance may affect brain plasticity of next generations is still unclear. Here, we demonstrate that maternal high fat diet (HFD)-dependent insulin resistance multigenerationally impairs synaptic plasticity, learning and memory. HFD downregulates BDNF and insulin signaling in maternal tissues and epigenetically inhibits BDNF expression in both germline and hippocampus of progeny. Notably, exposure of the HFD offspring to novel enriched environment restores Bdnf epigenetic activation in the male germline and counteracts the transmission of cognitive impairment to the next generations. BDNF administration to HFD-fed mothers or preserved insulin sensitivity in HFD-fed p66Shc KO mice also prevents the intergenerational transmission of brain damage to the progeny. Collectively, our data suggest that maternal diet multigenerationally impacts on descendants' brain health via gametic mechanisms susceptible to lifestyle.


Assuntos
Dieta Hiperlipídica/efeitos adversos , Resistência à Insulina , Aprendizagem/fisiologia , Memória/fisiologia , Plasticidade Neuronal/fisiologia , Animais , Fator Neurotrófico Derivado do Encéfalo/genética , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/genética , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/metabolismo , Epigênese Genética , Feminino , Proteína Forkhead Box O3/metabolismo , Regulação da Expressão Gênica , Hipocampo/fisiopatologia , Histona Desacetilase 2/metabolismo , Masculino , Camundongos Endogâmicos C57BL , Camundongos Knockout , Ovário/metabolismo , Sirtuína 2/metabolismo , Proteína 1 de Transformação que Contém Domínio 2 de Homologia de Src/genética
2.
Nat Neurosci ; 22(12): 2066-2077, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31659343

RESUMO

When learning the value of actions in volatile environments, humans often make seemingly irrational decisions that fail to maximize expected value. We reasoned that these 'non-greedy' decisions, instead of reflecting information seeking during choice, may be caused by computational noise in the learning of action values. Here using reinforcement learning models of behavior and multimodal neurophysiological data, we show that the majority of non-greedy decisions stem from this learning noise. The trial-to-trial variability of sequential learning steps and their impact on behavior could be predicted both by blood oxygen level-dependent responses to obtained rewards in the dorsal anterior cingulate cortex and by phasic pupillary dilation, suggestive of neuromodulatory fluctuations driven by the locus coeruleus-norepinephrine system. Together, these findings indicate that most behavioral variability, rather than reflecting human exploration, is due to the limited computational precision of reward-guided learning.


Assuntos
Tomada de Decisões/fisiologia , Aprendizagem/fisiologia , Recompensa , Adulto , Comportamento de Escolha/fisiologia , Feminino , Lobo Frontal/fisiologia , Humanos , Imagem por Ressonância Magnética , Masculino , Modelos Neurológicos , Neuroimagem , Pupila/fisiologia , Adulto Jovem
3.
Exp Psychol ; 66(5): 319-330, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31603046

RESUMO

Learners are more likely to remember what they study if they are motivated to do so. Such motivation can be externally driven by prospective rewards, but also intrinsically driven by curiosity. The present research focused on the role of curiosity during intentional learning. We examined the potential mnemonic benefit of curiosity, whether this benefit is undermined when learners are externally motivated to learn by rewards, and whether it can be attributed to increased study time for information they are more curious about. In two experiments, participants were presented with trivia questions, rated their level of curiosity about each question, and then studied the answers, either with or without a prospect of reward for correct recall on a subsequent test. Study time was either fixed (Experiment 1) or self-paced (Experiment 2). Performance on a memory test 1 week later suggested that curiosity enhanced long-term retention, and that rewards did not undermine the benefit of curiosity. When learning was self-paced, study time increased with curiosity but did not account for the effect of curiosity on memory. The results highlight the important role curiosity plays in learning and suggest that curiosity and rewards can be used together effectively to promote students' learning.


Assuntos
Comportamento Exploratório/fisiologia , Aprendizagem/fisiologia , Rememoração Mental/fisiologia , Motivação , Adulto , Feminino , Humanos , Masculino , Memória , Estudos Prospectivos , Recompensa , Adulto Jovem
4.
Medicina (B Aires) ; 79 Suppl 3: 29-32, 2019.
Artigo em Espanhol | MEDLINE | ID: mdl-31603840

RESUMO

Recent studies have demonstrated that while we are sleeping, our brain is very busy processing all information we have acquired along the day. Lack of sleep has shown to produce deficits in memory consolidation and plays an important role in brain development and brain plasticity in the several developmental stages of the human brain. At the cellular level, circadian cycles coordinate complex mechanism that "turn on and off" genes and cellular structures regulating individual cell functions to impact global organ and systems physiological activities. At the end a perfect and coordinated equilibrium in the mental, emotional and physiological is the goal of this complex process. Sleep impacts memory, learning, mood, behavior, immunological responses, metabolism, hormone levels, digestive process and many more physiological functions. We present a review of three basic aspects related with sleep: a. brain electrical activity during the sleep and neuroanatomic correlation with mechanism related with memory and learning; b. circadian cycles and impact in several physiological systems; c some examples of clinical disorders associated with sleep disorders and impact in learning and memory.


Assuntos
Ritmo Circadiano/fisiologia , Aprendizagem/fisiologia , Memória/fisiologia , Plasticidade Neuronal/fisiologia , Sono/fisiologia , Encéfalo/fisiologia , Emoções/fisiologia , Humanos , Transtornos do Sono-Vigília/fisiopatologia
5.
Nat Commun ; 10(1): 4429, 2019 09 27.
Artigo em Inglês | MEDLINE | ID: mdl-31562332

RESUMO

Learning associations between environmental cues and rewards is a fundamental adaptive function. Via such learning, reward-predictive cues come to activate approach to locations where reward is available. The nucleus accumbens (NAc) is essential for cued approach behavior in trained subjects, and cue-evoked excitations in NAc neurons are critical for the expression of this behavior. Excitatory synapses within the NAc undergo synaptic plasticity that presumably contributes to cued approach acquisition, but a direct link between synaptic plasticity within the NAc and the development of cue-evoked neural activity during learning has not been established. Here we show that, with repeated cue-reward pairings, cue-evoked excitations in the NAc emerge and grow in the trials prior to the detectable expression of cued approach behavior. We demonstrate that the growth of these signals requires NMDA receptor-dependent plasticity within the NAc, revealing a neural mechanism by which the NAc participates in learning of conditioned reward-seeking behaviors.


Assuntos
Sinais (Psicologia) , Aprendizagem/fisiologia , Núcleo Accumbens/metabolismo , Receptores de N-Metil-D-Aspartato/metabolismo , Recompensa , Animais , Comportamento Animal , Cânula , Masculino , Microeletrodos , Motivação , Plasticidade Neuronal , Neurônios/metabolismo , Ratos , Transdução de Sinais
6.
Nat Neurosci ; 22(11): 1857-1870, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31548723

RESUMO

Recent anatomical evidence suggests a functionally significant back-projection pathway from the subiculum to the CA1. Here we show that the afferent circuitry of CA1-projecting subicular neurons is biased by inputs from CA1 inhibitory neurons and the visual cortex, but lacks input from the entorhinal cortex. Efferents of the CA1-projecting subiculum neurons also target the perirhinal cortex, an area strongly implicated in object-place learning. We identify a critical role for CA1-projecting subicular neurons in object-location learning and memory, and show that this projection modulates place-specific activity of CA1 neurons and their responses to displaced objects. Together, these experiments reveal a novel pathway by which cortical inputs, particularly those from the visual cortex, reach the hippocampal output region CA1. Our findings also implicate this circuitry in the formation of complex spatial representations and learning of object-place associations.


Assuntos
Região CA1 Hipocampal/fisiologia , Córtex Entorrinal/fisiologia , Hipocampo/fisiologia , Aprendizagem/fisiologia , Córtex Perirrinal/fisiologia , Córtex Visual/fisiologia , Animais , Feminino , Masculino , Camundongos , Camundongos Transgênicos , Vias Neurais/fisiologia , Neurônios/fisiologia , Percepção Espacial/fisiologia
7.
Nat Neurosci ; 22(10): 1554-1564, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31551595

RESUMO

Brain-machine interfaces (BMIs) create closed-loop control systems that interact with the brain by recording and modulating neural activity and aim to restore lost function, most commonly motor function in paralyzed patients. Moreover, by precisely manipulating the elements within the control loop, motor BMIs have emerged as new scientific tools for investigating the neural mechanisms underlying control and learning. Beyond motor BMIs, recent work highlights the opportunity to develop closed-loop mood BMIs for restoring lost emotional function in neuropsychiatric disorders and for probing the neural mechanisms of emotion regulation. Here we review significant advances toward functional restoration and scientific discovery in motor BMIs that have been guided by a closed-loop control view. By focusing on this unifying view of BMIs and reviewing recent work, we then provide a perspective on how BMIs could extend to the neuropsychiatric domain.


Assuntos
Afeto/fisiologia , Interfaces Cérebro-Computador , Movimento/fisiologia , Animais , Humanos , Aprendizagem/fisiologia , Transtornos Mentais/fisiopatologia , Transtornos Mentais/psicologia , Transtornos Mentais/terapia
8.
Nat Neurosci ; 22(10): 1544-1553, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31551597

RESUMO

Arguably, the most difficult part of learning is deciding what to learn about. Should I associate the positive outcome of safely completing a street-crossing with the situation 'the car approaching the crosswalk was red' or with 'the approaching car was slowing down'? In this Perspective, we summarize our recent research into the computational and neural underpinnings of 'representation learning'-how humans (and other animals) construct task representations that allow efficient learning and decision-making. We first discuss the problem of learning what to ignore when confronted with too much information, so that experience can properly generalize across situations. We then turn to the problem of augmenting perceptual information with inferred latent causes that embody unobservable task-relevant information, such as contextual knowledge. Finally, we discuss recent findings regarding the neural substrates of task representations that suggest the orbitofrontal cortex represents 'task states', deploying them for decision-making and learning elsewhere in the brain.


Assuntos
Aprendizagem/fisiologia , Animais , Tomada de Decisões/fisiologia , Humanos , Córtex Pré-Frontal/fisiologia
9.
10.
Nat Neurosci ; 22(10): 1586-1597, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31551602

RESUMO

Emotional learning and memory are functionally and dysfunctionally regulated by the neuromodulatory state of the brain. While the role of excitatory and inhibitory neural circuits mediating emotional learning and its control have been the focus of much research, we are only now beginning to understand the more diffuse role of neuromodulation in these processes. Recent experimental studies of the acetylcholine, noradrenaline and dopamine systems in fear learning and extinction of fear responding provide surprising answers to key questions in neuromodulation. One area of research has revealed how modular organization, coupled with context-dependent coding modes, allows for flexible brain-wide or targeted neuromodulation. Other work has shown how these neuromodulators act in downstream targets to enhance signal-to-noise ratios and gain, as well as to bind distributed circuits through neuronal oscillations. These studies elucidate how different neuromodulatory systems regulate aversive emotional processing and reveal fundamental principles of neuromodulatory function.


Assuntos
Aprendizagem da Esquiva/fisiologia , Emoções/fisiologia , Rede Nervosa/fisiologia , Animais , Medo/fisiologia , Medo/psicologia , Humanos , Aprendizagem/fisiologia , Memória/fisiologia , Neurotransmissores/fisiologia
11.
Exp Psychol ; 66(4): 266-280, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31530246

RESUMO

Research on implicit sequence learning with the Serial Reaction Task (SRT) has demonstrated that people automatically acquire knowledge about fixed repeating sequences of responses and can transfer response sequence knowledge to novel stimuli. Such demonstrations are, however, mostly limited to setups with visual stimuli and manual responses. Here we systematically follow up on scarce attempts to demonstrate implicit sequence learning in word reading. While the literature on implicit sequence learning can be taken to suggest that sequence knowledge is acquired and affecting performance in word reading, we show that neither is the case in a series of four experiments. Sequence knowledge was acquired and affecting performance in color naming but not in word reading. On the one hand, we observed slowing of voice-onset times in off-sequence as compared to regularly sequenced trials when people named the color of a centrally presented disk. Yet, hardly any effect was observed when the very same sequence of words was verbalized in word reading instead. Transfer of sequence knowledge to and from color naming was not observed, either. This contrasts with sequence learning studies with manual responses, which have been taken to suggest that a fixed and repeating sequence of responses is sufficient for learning to occur even in fast choice reaction tasks and to transfer across stimuli as long as the sequence of responses remains intact. Rather, in line with dimensional action accounts of task performance, the results underline the role of translation between processing streams for implicit sequence learning.


Assuntos
Aprendizagem/fisiologia , Leitura , Análise e Desempenho de Tarefas , Feminino , Humanos , Masculino
12.
PLoS Comput Biol ; 15(9): e1007331, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31525176

RESUMO

Many models of classical conditioning fail to describe important phenomena, notably the rapid return of fear after extinction. To address this shortfall, evidence converged on the idea that learning agents rely on latent-state inferences, i.e. an ability to index disparate associations from cues to rewards (or penalties) and infer which index (i.e. latent state) is presently active. Our goal was to develop a model of latent-state inferences that uses latent states to predict rewards from cues efficiently and that can describe behavior in a diverse set of experiments. The resulting model combines a Rescorla-Wagner rule, for which updates to associations are proportional to prediction error, with an approximate Bayesian rule, for which beliefs in latent states are proportional to prior beliefs and an approximate likelihood based on current associations. In simulation, we demonstrate the model's ability to reproduce learning effects both famously explained and not explained by the Rescorla-Wagner model, including rapid return of fear after extinction, the Hall-Pearce effect, partial reinforcement extinction effect, backwards blocking, and memory modification. Lastly, we derive our model as an online algorithm to maximum likelihood estimation, demonstrating it is an efficient approach to outcome prediction. Establishing such a framework is a key step towards quantifying normative and pathological ranges of latent-state inferences in various contexts.


Assuntos
Biologia Computacional/métodos , Aprendizagem/fisiologia , Modelos Psicológicos , Algoritmos , Simulação por Computador , Condicionamento Clássico , Medo , Humanos
13.
PLoS Comput Biol ; 15(9): e1007334, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31490932

RESUMO

State-space and action representations form the building blocks of decision-making processes in the brain; states map external cues to the current situation of the agent whereas actions provide the set of motor commands from which the agent can choose to achieve specific goals. Although these factors differ across environments, it is currently unknown whether or how accurately state and action representations are acquired by the agent because previous experiments have typically provided this information a priori through instruction or pre-training. Here we studied how state and action representations adapt to reflect the structure of the world when such a priori knowledge is not available. We used a sequential decision-making task in rats in which they were required to pass through multiple states before reaching the goal, and for which the number of states and how they map onto external cues were unknown a priori. We found that, early in training, animals selected actions as if the task was not sequential and outcomes were the immediate consequence of the most proximal action. During the course of training, however, rats recovered the true structure of the environment and made decisions based on the expanded state-space, reflecting the multiple stages of the task. Similarly, we found that the set of actions expanded with training, although the emergence of new action sequences was sensitive to the experimental parameters and specifics of the training procedure. We conclude that the profile of choices shows a gradual shift from simple representations to more complex structures compatible with the structure of the world.


Assuntos
Biologia Computacional/métodos , Tomada de Decisões/fisiologia , Aprendizagem/fisiologia , Algoritmos , Animais , Comportamento Animal , Sinais (Psicologia) , Masculino , Modelos Biológicos , Ratos , Ratos Wistar
14.
PLoS Comput Biol ; 15(9): e1007326, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31490934

RESUMO

Value-based decision-making involves trading off the cost associated with an action against its expected reward. Research has shown that both physical and mental effort constitute such subjective costs, biasing choices away from effortful actions, and discounting the value of obtained rewards. Facing conflicts between competing action alternatives is considered aversive, as recruiting cognitive control to overcome conflict is effortful. Moreover, engaging control to proactively suppress irrelevant information that could conflict with task-relevant information would presumably also be cognitively costly. Yet, it remains unclear whether the cognitive control demands involved in preventing and resolving conflict also constitute costs in value-based decisions. The present study investigated this question by embedding irrelevant distractors (flanker arrows) within a reversal-learning task, with intermixed free and instructed trials. Results showed that participants learned to adapt their free choices to maximize rewards, but were nevertheless biased to follow the suggestions of irrelevant distractors. Thus, the perceived cost of investing cognitive control to suppress an external suggestion could sometimes trump internal value representations. By adapting computational models of reinforcement learning, we assessed the influence of conflict at both the decision and learning stages. Modelling the decision showed that free choices were more biased when participants were less sure about which action was more rewarding. This supports the hypothesis that the costs linked to conflict management were traded off against expected rewards. During the learning phase, we found that learning rates were reduced in instructed, relative to free, choices. Learning rates were further reduced by conflict between an instruction and subjective action values, whereas learning was not robustly influenced by conflict between one's actions and external distractors. Our results show that the subjective cognitive control costs linked to conflict factor into value-based decision-making, and highlight that different types of conflict may have different effects on learning about action outcomes.


Assuntos
Tomada de Decisões/fisiologia , Aprendizagem/fisiologia , Adulto , Biologia Computacional , Simulação por Computador , Feminino , Humanos , Masculino , Modelos Psicológicos , Recompensa , Adulto Jovem
15.
Nat Commun ; 10(1): 4004, 2019 09 05.
Artigo em Inglês | MEDLINE | ID: mdl-31488828

RESUMO

In rodents, cells in the medial entorhinal cortex (EC) and subiculum code for the allocentric direction to environment boundaries, which is an important prerequisite for accurate positional coding. Although in humans boundary-related signals have been reported, there is no evidence that they contain allocentric direction information. Furthermore, it has not been possible to separate boundary versus goal direction signals in the EC/subiculum. Here, to address these questions, we had participants learn a virtual environment containing four unique boundaries. Participants then underwent fMRI scanning where they made judgements about the allocentric direction of a cue object. Using multivariate decoding, we found information regarding allocentric boundary direction in posterior EC and subiculum, whereas allocentric goal direction was decodable from anterior EC and subiculum. These data provide the first evidence of allocentric boundary coding in humans, and are consistent with recent conceptualisations of a division of labour within the EC.


Assuntos
Córtex Entorrinal/fisiologia , Hipocampo/fisiologia , Adulto , Meio Ambiente , Feminino , Humanos , Aprendizagem/fisiologia , Imagem por Ressonância Magnética , Masculino , Memória/fisiologia , Navegação Espacial , Lobo Temporal , Disparidade Visual/fisiologia , Percepção Visual/fisiologia , Adulto Jovem
16.
Nat Commun ; 10(1): 3989, 2019 09 05.
Artigo em Inglês | MEDLINE | ID: mdl-31488845

RESUMO

When an action is familiar, we are able to anticipate how it will change the state of the world. These expectations can result from retrieval of action-outcome associations in the hippocampus and the reinstatement of anticipated outcomes in visual cortex. How does this role for the hippocampus in action-based prediction change over time? We use high-resolution fMRI and a dual-training behavioral paradigm to examine how the hippocampus interacts with visual cortex during predictive and nonpredictive actions learned either three days earlier or immediately before the scan. Just-learned associations led to comparable background connectivity between the hippocampus and V1/V2, regardless of whether actions predicted outcomes. However, three-day-old associations led to stronger background connectivity and greater differentiation between neural patterns for predictive vs. nonpredictive actions. Hippocampal prediction may initially reflect indiscriminate binding of co-occurring events, with action information pruning weaker associations and leading to more selective and accurate predictions over time.


Assuntos
Aprendizagem por Associação/fisiologia , Hipocampo/fisiologia , Aprendizagem/fisiologia , Neocórtex/fisiologia , Adolescente , Adulto , Mapeamento Encefálico , Feminino , Humanos , Imagem por Ressonância Magnética , Masculino , Memória , Lobo Temporal/fisiologia , Fatores de Tempo , Córtex Visual , Adulto Jovem
17.
Nat Neurosci ; 22(10): 1536-1543, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31477899

RESUMO

Activity-dependent synaptic plasticity has since long been proposed to represent the subcellular substrate of learning and memory, one of the most important behavioral processes through which we adapt to our environment. Despite the undisputed importance of synaptic plasticity for brain function, its exact contribution to learning processes in the context of cellular and connectivity modifications remains obscure. Causally bridging synaptic and behavioral modifications indeed remains limited by the available tools to measure and control synaptic strength and plasticity in vivo under behaviorally relevant conditions. After a brief summary of the current state of knowledge of the links between synaptic plasticity and learning, we will review and discuss the available and desired tools to progress in this endeavor.


Assuntos
Aprendizagem/fisiologia , Plasticidade Neuronal/fisiologia , Animais , Encéfalo/citologia , Encéfalo/fisiologia , Humanos , Vias Neurais/citologia , Vias Neurais/fisiologia
18.
PLoS Comput Biol ; 15(8): e1006695, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31398185

RESUMO

Plasticity in the oculomotor system ensures that saccadic eye movements reliably meet their visual goals-to bring regions of interest into foveal, high-acuity vision. Here, we present a comprehensive description of sensorimotor learning in saccades. We induced continuous adaptation of saccade amplitudes using a double-step paradigm, in which participants saccade to a peripheral target stimulus, which then undergoes a surreptitious, intra-saccadic shift (ISS) as the eyes are in flight. In our experiments, the ISS followed a systematic variation, increasing or decreasing from one saccade to the next as a sinusoidal function of the trial number. Over a large range of frequencies, we confirm that adaptation gain shows (1) a periodic response, reflecting the frequency of the ISS with a delay of a number of trials, and (2) a simultaneous drift towards lower saccade gains. We then show that state-space-based linear time-invariant systems (LTIS) represent suitable generative models for this evolution of saccade gain over time. This state-equation algorithm computes the prediction of an internal (or hidden state-) variable by learning from recent feedback errors, and it can be compared to experimentally observed adaptation gain. The algorithm also includes a forgetting rate that quantifies per-trial leaks in the adaptation gain, as well as a systematic, non-error-based bias. Finally, we study how the parameters of the generative models depend on features of the ISS. Driven by a sinusoidal disturbance, the state-equation admits an exact analytical solution that expresses the parameters of the phenomenological description as functions of those of the generative model. Together with statistical model selection criteria, we use these correspondences to characterize and refine the structure of compatible state-equation models. We discuss the relation of these findings to established results and suggest that they may guide further design of experimental research across domains of sensorimotor adaptation.


Assuntos
Adaptação Fisiológica , Modelos Biológicos , Movimentos Sacádicos/fisiologia , Algoritmos , Biologia Computacional , Humanos , Aprendizagem/fisiologia , Modelos Psicológicos
19.
Nat Neurosci ; 22(9): 1469-1476, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31406364

RESUMO

Vocal learners use early social experience to develop auditory skills specialized for communication. However, it is unknown where in the auditory pathway neural responses become selective for vocalizations or how the underlying encoding mechanisms change with experience. We used a vocal tutoring manipulation in two species of songbird to reveal that tuning for conspecific song arises within the primary auditory cortical circuit. Neurons in the deep region of primary auditory cortex responded more to conspecific songs than to other species' songs and more to species-typical spectrotemporal modulations, but neurons in the intermediate (thalamorecipient) region did not. Moreover, birds that learned song from another species exhibited parallel shifts in selectivity and tuning toward the tutor species' songs in the deep but not the intermediate region. Our results locate a region in the auditory processing hierarchy where an experience-dependent coding mechanism aligns auditory responses with the output of a learned vocal motor behavior.


Assuntos
Córtex Auditivo/fisiologia , Vias Auditivas/fisiologia , Aprendizagem/fisiologia , Vocalização Animal/fisiologia , Animais , Percepção Auditiva/fisiologia , Tentilhões/fisiologia , Neurônios/fisiologia
20.
Nat Commun ; 10(1): 3674, 2019 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-31417077

RESUMO

Midbrain dopamine neurons are known to encode reward prediction errors (RPE) used to update value predictions. Here, we examine whether RPE signals coded by midbrain dopamine neurons are modulated by the cost paid to obtain rewards, by recording from dopamine neurons in awake behaving monkeys during performance of an effortful saccade task. Dopamine neuron responses to cues predicting reward and to the delivery of rewards were increased after the performance of a costly action compared to a less costly action, suggesting that RPEs are enhanced following the performance of a costly action. At the behavioral level, stimulus-reward associations are learned faster after performing a costly action compared to a less costly action. Thus, information about action cost is processed in the dopamine reward system in a manner that amplifies the following dopamine RPE signal, which in turn promotes more rapid learning under situations of high cost.


Assuntos
Neurônios Dopaminérgicos/fisiologia , Aprendizagem/fisiologia , Recompensa , Animais , Sinais (Psicologia) , Mesencéfalo/citologia , Mesencéfalo/fisiologia , Movimentos Sacádicos
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