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1.
Nat Commun ; 12(1): 4440, 2021 07 21.
Artigo em Inglês | MEDLINE | ID: mdl-34290236

RESUMO

Reinforcement learning is a fundamental mechanism displayed by many species. However, adaptive behaviour depends not only on learning about actions and outcomes that affect ourselves, but also those that affect others. Using computational reinforcement learning models, we tested whether young (age 18-36) and older (age 60-80, total n = 152) adults learn to gain rewards for themselves, another person (prosocial), or neither individual (control). Detailed model comparison showed that a model with separate learning rates for each recipient best explained behaviour. Young adults learned faster when their actions benefitted themselves, compared to others. Compared to young adults, older adults showed reduced self-relevant learning rates but preserved prosocial learning. Moreover, levels of subclinical self-reported psychopathic traits (including lack of concern for others) were lower in older adults and the core affective-interpersonal component of this measure negatively correlated with prosocial learning. These findings suggest learning to benefit others is preserved across the lifespan with implications for reinforcement learning and theories of healthy ageing.


Assuntos
Envelhecimento/psicologia , Comportamento de Ajuda , Reforço Psicológico , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Transtorno da Personalidade Antissocial/psicologia , Feminino , Humanos , Aprendizagem/fisiologia , Masculino , Pessoa de Meia-Idade , Modelos Psicológicos , Recompensa , Adulto Jovem
2.
Neuron ; 109(14): 2353-2361.e11, 2021 07 21.
Artigo em Inglês | MEDLINE | ID: mdl-34171289

RESUMO

To navigate social environments, people must simultaneously hold representations about their own and others' abilities. During self-other mergence, people estimate others' abilities not only on the basis of the others' past performance, but the estimates are also influenced by their own performance. For example, if we perform well, we overestimate the abilities of those with whom we are co-operating and underestimate competitors. Self-other mergence is associated with specific activity patterns in the dorsomedial prefrontal cortex (dmPFC). Using a combination of non-invasive brain stimulation, functional magnetic resonance imaging, and computational modeling, we show that dmPFC neurostimulation silences these neural signatures of self-other mergence in relation to estimation of others' abilities. In consequence, self-other mergence behavior increases, and our assessments of our own performance are projected increasingly onto other people. This suggests an inherent tendency to form interdependent social representations and a causal role of the dmPFC in separating self and other representations.


Assuntos
Modelos Neurológicos , Córtex Pré-Frontal/fisiologia , Percepção Social , Adolescente , Adulto , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Córtex Pré-Frontal/diagnóstico por imagem , Tempo de Reação/fisiologia , Comportamento Social , Estimulação Magnética Transcraniana , Adulto Jovem
3.
Neuron ; 109(8): 1396-1408.e7, 2021 04 21.
Artigo em Inglês | MEDLINE | ID: mdl-33730554

RESUMO

More than one type of probability must be considered when making decisions. It is as necessary to know one's chance of performing choices correctly as it is to know the chances that desired outcomes will follow choices. We refer to these two choice contingencies as internal and external probability. Neural activity across many frontal and parietal areas reflected internal and external probabilities in a similar manner during decision-making. However, neural recording and manipulation approaches suggest that one area, the anterior lateral prefrontal cortex (alPFC), is highly specialized for making prospective, metacognitive judgments on the basis of internal probability; it is essential for knowing which decisions to tackle, given its assessment of how well they will be performed. Its activity predicted prospective metacognitive judgments, and individual variation in activity predicted individual variation in metacognitive judgments. Its disruption altered metacognitive judgments, leading participants to tackle perceptual decisions they were likely to fail.


Assuntos
Julgamento/fisiologia , Metacognição/fisiologia , Córtex Pré-Frontal/fisiologia , Adulto , Mapeamento Encefálico , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Testes Neuropsicológicos , Córtex Pré-Frontal/diagnóstico por imagem , Estudos Prospectivos , Estimulação Magnética Transcraniana
4.
Nat Hum Behav ; 5(1): 83-98, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-32868885

RESUMO

Environments furnish multiple information sources for making predictions about future events. Here we use behavioural modelling and functional magnetic resonance imaging to describe how humans select predictors that might be most relevant. First, during early encounters with potential predictors, participants' selections were explorative and directed towards subjectively uncertain predictors (positive uncertainty effect). This was particularly the case when many future opportunities remained to exploit knowledge gained. Then, preferences for accurate predictors increased over time, while uncertain predictors were avoided (negative uncertainty effect). The behavioural transition from positive to negative uncertainty-driven selections was accompanied by changes in the representations of belief uncertainty in ventromedial prefrontal cortex (vmPFC). The polarity of uncertainty representations (positive or negative encoding of uncertainty) changed between exploration and exploitation periods. Moreover, the two periods were separated by a third transitional period in which beliefs about predictors' accuracy predominated. The vmPFC signals a multiplicity of decision variables, the strength and polarity of which vary with behavioural context.


Assuntos
Comportamento Exploratório/fisiologia , Córtex Pré-Frontal/fisiologia , Incerteza , Teorema de Bayes , Encéfalo/diagnóstico por imagem , Encéfalo/fisiologia , Comportamento de Escolha/fisiologia , Feminino , Neuroimagem Funcional , Humanos , Julgamento/fisiologia , Imageamento por Ressonância Magnética , Masculino , Córtex Pré-Frontal/diagnóstico por imagem , Adulto Jovem
5.
Nat Commun ; 11(1): 3771, 2020 07 28.
Artigo em Inglês | MEDLINE | ID: mdl-32724052

RESUMO

People and other animals learn the values of choices by observing the contingencies between them and their outcomes. However, decisions are not guided by choice-linked reward associations alone; macaques also maintain a memory of the general, average reward rate - the global reward state - in an environment. Remarkably, global reward state affects the way that each choice outcome is valued and influences future decisions so that the impact of both choice success and failure is different in rich and poor environments. Successful choices are more likely to be repeated but this is especially the case in rich environments. Unsuccessful choices are more likely to be abandoned but this is especially likely in poor environments. Functional magnetic resonance imaging (fMRI) revealed two distinct patterns of activity, one in anterior insula and one in the dorsal raphe nucleus, that track global reward state as well as specific outcome events.


Assuntos
Córtex Cerebral/fisiologia , Comportamento de Escolha/fisiologia , Modelos Neurológicos , Núcleos da Rafe/fisiologia , Recompensa , Animais , Comportamento Animal , Córtex Cerebral/diagnóstico por imagem , Processamento de Imagem Assistida por Computador , Macaca mulatta , Imageamento por Ressonância Magnética , Masculino , Modelos Animais , Núcleos da Rafe/diagnóstico por imagem
6.
Nat Commun ; 10(1): 4835, 2019 10 23.
Artigo em Inglês | MEDLINE | ID: mdl-31645545

RESUMO

Learning the structure of the world can be driven by reinforcement but also occurs incidentally through experience. Reinforcement learning theory has provided insight into how prediction errors drive updates in beliefs but less attention has been paid to the knowledge resulting from such learning. Here we contrast associative structures formed through reinforcement and experience of task statistics. BOLD neuroimaging in human volunteers demonstrates rigid representations of rewarded sequences in temporal pole and posterior orbito-frontal cortex, which are constructed backwards from reward. By contrast, medial prefrontal cortex and a hippocampal-amygdala border region carry reward-related knowledge but also flexible statistical knowledge of the currently relevant task model. Intriguingly, ventral striatum encodes prediction error responses but not the full RL- or statistically derived task knowledge. In summary, representations of task knowledge are derived via multiple learning processes operating at different time scales that are associated with partially overlapping and partially specialized anatomical regions.


Assuntos
Aprendizagem por Associação/fisiologia , Encéfalo/diagnóstico por imagem , Reforço Psicológico , Adulto , Tonsila do Cerebelo/diagnóstico por imagem , Tonsila do Cerebelo/fisiologia , Encéfalo/fisiologia , Feminino , Neuroimagem Funcional , Hipocampo/diagnóstico por imagem , Hipocampo/fisiologia , Humanos , Aprendizagem/fisiologia , Imageamento por Ressonância Magnética , Masculino , Córtex Pré-Frontal/diagnóstico por imagem , Córtex Pré-Frontal/fisiologia , Lobo Temporal/diagnóstico por imagem , Lobo Temporal/fisiologia , Estriado Ventral/diagnóstico por imagem , Estriado Ventral/fisiologia , Adulto Jovem
7.
Nat Commun ; 9(1): 4747, 2018 11 12.
Artigo em Inglês | MEDLINE | ID: mdl-30420714

RESUMO

Sense of ownership is a ubiquitous and fundamental aspect of human cognition. Here we used model-based functional magnetic resonance imaging and a novel minimal ownership paradigm to probe the behavioural and neural mechanisms underpinning ownership acquisition for ourselves, friends and strangers. We find a self-ownership bias at multiple levels of behaviour from initial preferences to reaction times and computational learning rates. Ventromedial prefrontal cortex (vmPFC) and anterior cingulate sulcus (ACCs) responded more to self vs. stranger associations, but despite a pervasive neural bias to track self-ownership, no brain area tracked self-ownership exclusively. However, ACC gyrus (ACCg) specifically coded ownership prediction errors for strangers and ownership associative strength for friends and strangers but not for self. Core neural mechanisms for associative learning are biased to learn in reference to self but also engaged when learning in reference to others. In contrast, ACC gyrus exhibits specialization for learning about others.


Assuntos
Encéfalo/fisiologia , Aprendizagem , Propriedade , Autoimagem , Adulto , Feminino , Giro do Cíngulo/fisiologia , Humanos , Masculino , Córtex Pré-Frontal/fisiologia , Adulto Jovem
8.
Neurosci Biobehav Rev ; 92: 187-191, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-29886177

RESUMO

Studies in the field of social neuroscience have recently made use of computational models of decision-making to provide new insights into how we learn about the self and others during social interactions. Importantly, these studies have increasingly drawn attention to brain areas outside of classical cortical "social brain" regions that may be critical for social processing. In particular, two portions of the ventral anterior cingulate cortex (vACC), subgenual anterior cingulate cortex and perigenual anterior cingulate cortex, have been linked to social and self learning signals, respectively. Here we discuss the emerging parallels between these studies. Uncovering the function of vACC during social interactions could provide important new avenues to understand social decision-making in health and disease.


Assuntos
Mapeamento Encefálico , Tomada de Decisões/fisiologia , Giro do Cíngulo/fisiologia , Relações Interpessoais , Humanos
9.
Annu Rev Neurosci ; 41: 99-118, 2018 07 08.
Artigo em Inglês | MEDLINE | ID: mdl-29561702

RESUMO

Activity in a network of areas spanning the superior temporal sulcus, dorsomedial frontal cortex, and anterior cingulate cortex is concerned with how nonhuman primates negotiate the social worlds in which they live. Central aspects of these circuits are retained in humans. Activity in these areas codes for primates' interactions with one another, their attempts to find out about one another, and their attempts to prevent others from finding out too much about themselves. Moreover, important features of the social world, such as dominance status, cooperation, and competition, modulate activity in these areas. We consider the degree to which activity in these regions is simply encoding an individual's own actions and choices or whether this activity is especially and specifically concerned with social cognition. Recent advances in comparative anatomy and computational modeling may help us to gain deeper insights into the nature and boundaries of primate social cognition.


Assuntos
Mapeamento Encefálico , Encéfalo/fisiologia , Cognição/fisiologia , Vias Neurais/fisiologia , Comportamento Social , Animais , Humanos , Primatas
10.
Nat Commun ; 8(1): 1886, 2017 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-29192186

RESUMO

Ventromedial prefrontal cortex has been linked to choice evaluation and decision-making in humans but understanding the role it plays is complicated by the fact that little is known about the corresponding area of the macaque brain. We recorded activity in macaques using functional magnetic resonance imaging during two very different value-guided decision-making tasks. In both cases ventromedial prefrontal cortex activity reflected subjective choice values during decision-making just as in humans but the relationship between the blood oxygen level-dependent signal and both decision-making and choice value was inverted and opposite to the relationship seen in humans. In order to test whether the ventromedial prefrontal cortex activity related to choice values is important for decision-making we conducted an additional lesion experiment; lesions that included the same ventromedial prefrontal cortex region disrupted normal subjective evaluation of choices during decision-making.


Assuntos
Tomada de Decisões , Córtex Pré-Frontal/fisiologia , Animais , Comportamento de Escolha , Feminino , Macaca , Imageamento por Ressonância Magnética , Masculino , Córtex Pré-Frontal/diagnóstico por imagem
11.
Nat Commun ; 8(1): 1942, 2017 12 05.
Artigo em Inglês | MEDLINE | ID: mdl-29208968

RESUMO

Decisions are based on value expectations derived from experience. We show that dorsal anterior cingulate cortex and three other brain regions hold multiple representations of choice value based on different timescales of experience organized in terms of systematic gradients across the cortex. Some parts of each area represent value estimates based on recent reward experience while others represent value estimates based on experience over the longer term. The value estimates within these areas interact with one another according to their temporal scaling. Some aspects of the representations change dynamically as the environment changes. The spectrum of value estimates may act as a flexible selection mechanism for combining experience-derived value information with other aspects of value to allow flexible and adaptive decisions in changing environments.


Assuntos
Tomada de Decisões/fisiologia , Giro do Cíngulo/fisiologia , Lobo Parietal/fisiologia , Reversão de Aprendizagem/fisiologia , Encéfalo/diagnóstico por imagem , Encéfalo/fisiologia , Comportamento de Escolha/fisiologia , Neuroimagem Funcional , Giro do Cíngulo/diagnóstico por imagem , Humanos , Imageamento por Ressonância Magnética , Lobo Parietal/diagnóstico por imagem , Probabilidade
12.
Nat Neurosci ; 19(10): 1280-5, 2016 09 27.
Artigo em Inglês | MEDLINE | ID: mdl-27669988

RESUMO

Dorsal anterior cingulate cortex (dACC) carries a wealth of value-related information necessary for regulating behavioral flexibility and persistence. It signals error and reward events informing decisions about switching or staying with current behavior. During decision-making, it encodes the average value of exploring alternative choices (search value), even after controlling for response selection difficulty, and during learning, it encodes the degree to which internal models of the environment and current task must be updated. dACC value signals are derived in part from the history of recent reward integrated simultaneously over multiple time scales, thereby enabling comparison of experience over the recent and extended past. Such ACC signals may instigate attentionally demanding and difficult processes such as behavioral change via interactions with prefrontal cortex. However, the signal in dACC that instigates behavioral change need not itself be a conflict or difficulty signal.


Assuntos
Tomada de Decisões/fisiologia , Giro do Cíngulo/fisiologia , Recompensa , Animais , Atenção/fisiologia , Comportamento de Escolha/fisiologia , Humanos , Aprendizagem/fisiologia , Neurônios/fisiologia , Córtex Pré-Frontal/fisiologia
13.
Nat Commun ; 7: 12327, 2016 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-27477632

RESUMO

In many natural environments the value of a choice gradually gets better or worse as circumstances change. Discerning such trends makes predicting future choice values possible. We show that humans track such trends by comparing estimates of recent and past reward rates, which they are able to hold simultaneously in the dorsal anterior cingulate cortex (dACC). Comparison of recent and past reward rates with positive and negative decision weights is reflected by opposing dACC signals indexing these quantities. The relative strengths of time-linked reward representations in dACC predict whether subjects persist in their current behaviour or switch to an alternative. Computationally, trend-guided choice can be modelled by using a reinforcement-learning mechanism that computes a longer-term estimate (or expectation) of prediction errors. Using such a model, we find a relative predominance of expected prediction errors in dACC, instantaneous prediction errors in the ventral striatum and choice signals in the ventromedial prefrontal cortex.


Assuntos
Comportamento de Escolha/fisiologia , Giro do Cíngulo/fisiologia , Córtex Pré-Frontal/fisiologia , Recompensa , Adulto , Atenção/fisiologia , Feminino , Giro do Cíngulo/diagnóstico por imagem , Humanos , Aprendizagem/fisiologia , Imageamento por Ressonância Magnética , Masculino , Modelos Biológicos , Córtex Pré-Frontal/diagnóstico por imagem , Fatores de Tempo , Adulto Jovem
14.
Neuron ; 91(2): 482-93, 2016 07 20.
Artigo em Inglês | MEDLINE | ID: mdl-27477020

RESUMO

To survive, humans must estimate their own ability and the abilities of others. We found that, although people estimated their abilities on the basis of their own performance in a rational manner, their estimates of themselves were partly merged with the performance of others. Reciprocally, their ability estimates for others also reflected their own, as well as the others', performance. Self-other mergence operated in a context-dependent manner: interacting with high or low performers, respectively, enhanced and diminished own ability estimates in cooperative contexts, but the opposite occurred in competitive contexts. Self-other mergence not only influenced subjective evaluations, it also affected how people subsequently objectively adjusted their performance. Perigenual anterior cingulate cortex tracked one's own performance. Dorsomedial frontal area 9 tracked others' performances, but also integrated contextual and self-related information. Self-other mergence increased with the strength of self and other representations in area 9, suggesting it carries interdependent representations of self and other.


Assuntos
Mapeamento Encefálico , Lobo Frontal , Relações Interpessoais , Comportamento Social , Adulto , Feminino , Giro do Cíngulo/fisiologia , Humanos , Processamento de Imagem Assistida por Computador , Imageamento por Ressonância Magnética , Masculino , Adulto Jovem
15.
J Neurosci ; 35(32): 11233-51, 2015 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-26269633

RESUMO

UNLABELLED: Natural environments are complex, and a single choice can lead to multiple outcomes. Agents should learn which outcomes are due to their choices and therefore relevant for future decisions and which are stochastic in ways common to all choices and therefore irrelevant for future decisions between options. We designed an experiment in which human participants learned the varying reward and effort magnitudes of two options and repeatedly chose between them. The reward associated with a choice was randomly real or hypothetical (i.e., participants only sometimes received the reward magnitude associated with the chosen option). The real/hypothetical nature of the reward on any one trial was, however, irrelevant for learning the longer-term values of the choices, and participants ought to have only focused on the informational content of the outcome and disregarded whether it was a real or hypothetical reward. However, we found that participants showed an irrational choice bias, preferring choices that had previously led, by chance, to a real reward in the last trial. Amygdala and ventromedial prefrontal activity was related to the way in which participants' choices were biased by real reward receipt. By contrast, activity in dorsal anterior cingulate cortex, frontal operculum/anterior insula, and especially lateral anterior prefrontal cortex was related to the degree to which participants resisted this bias and chose effectively in a manner guided by aspects of outcomes that had real and more sustained relationships with particular choices, suppressing irrelevant reward information for more optimal learning and decision making. SIGNIFICANCE STATEMENT: In complex natural environments, a single choice can lead to multiple outcomes. Human agents should only learn from outcomes that are due to their choices, not from outcomes without such a relationship. We designed an experiment to measure learning about reward and effort magnitudes in an environment in which other features of the outcome were random and had no relationship with choice. We found that, although people could learn about reward magnitudes, they nevertheless were irrationally biased toward repeating certain choices as a function of the presence or absence of random reward features. Activity in different brain regions in the prefrontal cortex either reflected the bias or reflected resistance to the bias.


Assuntos
Encéfalo/fisiologia , Comportamento de Escolha/fisiologia , Aprendizagem/fisiologia , Recompensa , Adulto , Interfaces Cérebro-Computador , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Modelos Neurológicos , Adulto Jovem
16.
Front Psychol ; 5: 636, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25009519

RESUMO

Objects are reminiscent of actions often performed with them:knife and apple remind us on peeling the apple or cutting it. Mnemonic representations of object-related actions (action codes) evoked by the sight of an object may constrain and hence facilitate recognition of unrolling actions. The present fMRI study investigated if and how action codes influence brain activation during action observation. The average number of action codes (NAC) of 51 sets of objects was rated by a group of n = 24 participants. In an fMRI study, different volunteers were asked to recognize actions performed with the same objects presented in short videos. To disentangle areas reflecting the storage of action codes from those exploiting them, we showed object-compatible and object-incompatible (pantomime) actions. Areas storing action codes were considered to positively co-vary with NAC in both object-compatible and object-incompatible action; due to its role in tool-related tasks, we here hypothesized left anterior inferior parietal cortex (aIPL). In contrast, areas exploiting action codes were expected to show this correlation only in object-compatible but not incompatible action, as only object-compatible actions match one of the active action codes. For this interaction, we hypothesized ventrolateral premotor cortex (PMv) to join aIPL due to its role in biasing competition in IPL. We found left anterior intraparietal sulcus (IPS) and left posterior middle temporal gyrus (pMTG) to co-vary with NAC. In addition to these areas, action codes increased activity in object-compatible action in bilateral PMv, right IPS, and lateral occipital cortex (LO). Findings suggest that during action observation, the brain derives possible actions from perceived objects, and uses this information to shape action recognition. In particular, the number of expectable actions quantifies the activity level at PMv, IPL, and pMTG, but only PMv reflects their biased competition while observed action unfolds.

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